TPSM84824MOLR - TEXAS INSTRUMENTS

Quad PLL, Quad Input, Multiservice Line

Card Adaptive Clock Translator

Data Sheet AD9554-1

Rev. C Document Feedback

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FEATURES

Supports GR-1244 Stratum 3 stability in holdover mode

Supports smooth reference switchover with virtually no

disturbance on output phase

Supports Telcordia GR-253 jitter generation, transfer, and

tolerance for SONET/SDH up to OC-192 systems

Supports ITU-T G.8262 synchronous Ethernet slave clocks

Supports ITU-T G.823, ITU-T G.824, ITU-T G.825, and

ITU-T G.8261

Auto/manual holdover and reference switchover

Adaptive clocking allows dynamic adjustment of feedback

dividers for use in OTN mapping/demapping applications

Quad digital phase-locked loop (DPLL) architecture with four

reference inputs (single-ended or differential)

4 × 4 crosspoint allows any reference input to drive any PLL

Input reference frequencies from 2 kHz to 1000 MHz

Reference validation and frequency monitoring: 2 ppm

Programmable input reference switchover priority

20-bit programmable input reference divider

4 differential clock outputs with each differential pair

configurable as HCSL, LVDS-compatible, or LVPECL-

compatible

Output frequency range: 430 kHz to 941 MHz

Programmable 18-bit integer and 24-bit fractional feedback

divider in digital PLL

Programmable loop bandwidths from 0.1 Hz to 4 kHz

56-lead (8 mm × 8 mm) LFCSP package

APPLICATIONS

Network synchronization, including synchronous Ethernet

and synchronous digital hierarchy (SDH) to optical

transport network (OTN) mapping/demapping

Cleanup of reference clock jitter

SONET/SDH clocks up to OC-192, including FEC

Stratum 3 holdover, jitter cleanup, and phase transient

control

Cable infrastructure

Data communications

Professional video

GENERAL DESCRIPTION

The AD9554-1 is a low loop bandwidth clock translator that

provides jitter cleanup and synchronization for many systems,

including synchronous optical networks (SONET/SDH). The

AD9554-1 generates an output clock synchronized to up to four

external input references. The digital PLLs (DPLLs) allow

reduction of input time jitter or phase noise associated with the

external references. The digitally controlled loop and holdover

circuitry of the AD9554-1 continuously generates a low jitter

output clock even when all reference inputs have failed.

The AD9554-1 operates over an industrial temperature range of

−40°C to +85°C. The AD9554 is a version of this device with

two outputs per PLL. If a single or dual DPLL version of this

device is needed, refer to the AD9557 or AD9559, respectively.

FUNCTIONAL BLOCK DIAGRAM

REFERENCE

INPUT

MONITOR

AND MUX

STABLE

SOURCE

DIGITAL

PLL1

DIGITAL

PLL2

CLOCK

MULTIPLIER

ANALOG

PLL1

ANALOG

PLL2

÷3 TO ÷11

P1 DIVIDER

÷3 TO ÷11

P2 DIVIDER

SERIAL INTERFACE

(SPI OR I

STATUS AND

CONTROL PINS

AD9554-1

DIGITAL

PLL3

ANALOG

PLL3

÷3 TO ÷11

P3 DIVIDER

DIGITAL

PLL0

ANALOG

PLL0

÷3 TO ÷11

P0 DIVIDER

Q3_B DIVIDER

Q2_B DIVIDER

Q1_B DIVIDER

Q0_B DIVIDER

12214-001

Figure 1.

AD9554-1 Data Sheet

Rev. C | Page 2 of 99

TABLE OF CONTENTS

Features .............................................................................................. 1

Applications ....................................................................................... 1

General Description ......................................................................... 1

Functional Block Diagram .............................................................. 1

Revision History ............................................................................... 4

Specifications ..................................................................................... 5 

Supply Voltage ............................................................................... 5

Supply Current .............................................................................. 5

Power Dissipation ......................................................................... 6

System Clock Inputs (XOA, XOB) ............................................. 6

Reference Inputs ........................................................................... 7

Reference Monitors ...................................................................... 8

Reference Switchover Specifications .......................................... 8

Distribution Clock Outputs ........................................................ 9

Time Duration of Digital Functions ........................................ 11

Digital PLL (DPLL_0, DPLL_1, DPLL_2, and DPLL_3) ...... 11

Analog PLL (APLL_0, APLL_1, APLL_2, and APLL_3) ...... 11

Digital PLL Lock Detection ...................................................... 12

Holdover Specifications ............................................................. 12

Serial Port Specifications—Serial Port Interface (SPI) Mode .... 12

Serial Port Specifications—I2C Mode ...................................... 13

Logic Inputs (RESET, M0 to M3, M5 to M7) ......................... 14

Logic Outputs (M0 to M3 and M5 to M7) .............................. 14

Jitter Generation ......................................................................... 14

Absolute Maximum Ratings .......................................................... 16

ESD Caution ................................................................................ 16

Pin Configuration and Function Descriptions ........................... 17

Typical Performance Characteristics ........................................... 20

Input/Output Termination Recommendations .......................... 23

Getting Started ................................................................................ 24

Chip Power Monitor and Startup ............................................. 24

Multifunction Pins at Reset/Power-Up ................................... 24

Device Register Programming Using a Register Setup File ....... 24

Theory of Operation ...................................................................... 31

Overvie w ...................................................................................... 31

Reference Input Physical Connections .................................... 32

Reference Monitors .................................................................... 32

Reference Input Block ................................................................ 32

Reference Switchover ................................................................. 33

Digital PLL (DPLL) Core .......................................................... 33

Loop Control State Machine ..................................................... 36

System Clock (SYSCLK) ................................................................ 37

SYSCLK Inputs ........................................................................... 37

SYSCLK Multiplier ..................................................................... 37

Output Analog PLL (APLL) .......................................................... 39

APLL Configuration .................................................................. 39

APLL Calibration ....................................................................... 39

Clock Distribution .......................................................................... 40

Clock Dividers ............................................................................ 40

Output Amplitude and Power-Down ...................................... 40

Clock Distribution Synchronization ........................................ 41

Status and Control .......................................................................... 42

Multifunction Pins (M0 to M3 and M5 to M7) ......................... 42

IRQ Function .............................................................................. 42

Watchdog Timer ......................................................................... 43

Serial Control Port ......................................................................... 44

SPI/IC Port Selection ................................................................ 44

SPI Serial Port Operation .......................................................... 44

IC Serial Port Operation .......................................................... 47

Programming the I/O Registers ................................................... 50

Buffered/Active Registers .......................................................... 50

Write Detect Registers ............................................................... 50

Autoclear Registers ..................................................................... 50

Thermal Performance .................................................................... 51

Power Supply Partitions ................................................................. 52

VDD Supplies ............................................................................. 52

VDD_SP Supply ......................................................................... 52

Serial Control Port Configuration (Register 0x0000 to

Clock Part Family ID (Register 0x0003 to Register 0x0006) ..... 63

SPI Version (Register 0x000B) .................................................. 64

Vendor ID (Register 0x000C to Register 0x000D) ................ 64

IO_Update (Register 0x000F) ................................................... 64

General Configuration (Register 0x0100 to Register 0x010E) .. 64

IRQ Mask (Register 0x010F to Register 0x011F) ................... 65

System Clock (Register 0x0200 to Register 0x0208) ............. 67

Data Sheet AD9554-1

Rev. C | Page 3 of 99

Reference Input A (Register 0x0300 to Register 0x031E) ...... 68

Reference Input B (Register 0x0320 to Register 0x033E) ...... 70

Reference Input C (Register 0x0340 to Register 0x035E) ...... 70

Reference Input D (Register 0x0360 to Register 0x037E) ..... 70

DPLL_0 Controls (Register 0x0400 to Register 0x041E) ....... 70

APLL_0 Configuration (Register 0x0430 to Register 0x0434) ... 72

Output PLL_0 (APLL_0) Sync and Clock Distribution

(Register 0x0434 to Register 0x043E) ....................................... 73

DPLL_0 Settings for Reference Input A (REFA)

(Register 0x0440 to Register 0x044C) ...................................... 74

DPLL_0 Settings for Reference Input B (REFB)

(Register 0x044D to Register 0x0459) ...................................... 75

DPLL_0 Settings for Reference Input C (REFC)

(Register 0x045A to Register 0x0466) ...................................... 76

DPLL_0 Settings for Reference Input D (REFD)

(Register 0x0467 to Register 0x0473) ....................................... 77

DPLL_1 Controls (Register 0x0500 to Register 0x051E) ....... 78

APLL_1 Configuration (Register 0x0530 to Register 0x0533) ... 78

PLL_1 Output Sync and Clock Distribution (Register 0x0534

to Register 0x053E) ..................................................................... 78

DPLL_1 Settings for Reference Input A (REFA)

(Register 0x0540 to Register 0x054C) ...................................... 78

DPLL_1 Settings for Reference Input B (REFB)

(Register 0x054D to Register 0x0559) ...................................... 78

DPLL_1 Settings for Reference Input C (REFC)

(Register 0x055A to Register 0x0566) ...................................... 79

DPLL_1 Settings for Reference Input D (REFD)

(Register 0x0567 to Register 0x0573) ....................................... 79

DPLL_2 Controls (Register 0x0600 to Register 0x061E) ....... 79

APLL_2 Configuration (Register 0x0630 to Register 0x0633) ... 79

PLL_2 Output Sync and Clock Distribution (Register 0x0634

to Register 0x063E) ..................................................................... 79

DPLL_2 Settings for Reference Input A (REFA)

(Register 0x0640 to Register 0x064C) ...................................... 79

DPLL_2 Settings for Reference Input B (REFB)

(Register 0x064D to Register 0x0659) ...................................... 79

DPLL_2 Settings for Reference Input C (REFC)

(Register 0x065A to Register 0x0666) ...................................... 79

DPLL_2 Settings for Reference Input D (REFD)

(Register 0x0667 to Register 0x0673) ....................................... 79

DPLL_3 Controls (Register 0x0700 to Register 0x071E) ........... 79

APLL_3 Configuration (Register 0x0730 to Register 0x0733) .. 79

PLL_3 Output Sync and Clock Distribution (Register 0x0734

to Register 0x073E) ..................................................................... 79

DPLL_3 Settings for Reference Input A (REFA)

(Register 0x0740 to Register 0x074C) ...................................... 79

DPLL_3 Settings for Reference Input B (REFB)

(Register 0x074D to Register 0x0759) ...................................... 79

DPLL_3 Settings for Reference Input C (REFC)

(Register 0x075A to Register 0x0766) ...................................... 80

DPLL_3 Settings for Reference Input D (REFD)

(Register 0x0767 to Register 0x0773) ....................................... 80

Digital Loop Filter Coefficients (Register 0x0800 to

Common Operational Controls (Register 0x0A00 to

IRQ Clearing (Register 0x0A05 to Register 0x0A14) ............ 83

PLL_0 Operational Controls (Register 0x0A20 to

PLL_1 Operational Controls (Register 0x0A40 to

PLL_2 Operational Controls (Register 0x0A60 to

PLL_3 Operational Controls (Register 0x0A80 to

Voltage Regulator (Register 0x0B00 to Register 0x0B01) ...... 88

Status Readback (Register 0x0D01 to Register 0x0D05) ....... 88

IRQ Monitor (Register 0x0D08 to Register 0x0D16) ............ 90

PLL_0 Read Only Status (Register 0x0D20 to

PLL_1 Read Only Status (Register 0x0D40 to

PLL_2 Read Only Status (Register 0x0D60 to

PLL_3 Read Only Status (Register 0x0D80 to

Outline Dimensions ........................................................................ 99

Ordering Guide ........................................................................... 99

AD9554-1 Data Sheet

Rev. C | Page 4 of 99

REVISION HISTORY

3/2017—Rev. B to Rev. C

Changes to Chip Power and Startup Section .............................. 24

Changes to Figure 25 ...................................................................... 25

Changes to Outline Dimensions ................................................... 99

Changes to Ordering Guide .......................................................... 99

10/2016—Rev. A to Rev. B

Changes to Figure 2 ........................................................................ 17

Deleted Figure 3; Renumbered Sequentially ............................... 20

Changes to Device Register Programming Using a Register

Setup File Section ........................................................................... 24

Added Figure 26; Renumbered Sequentially .............................. 25

Added Figure 27 .............................................................................. 26

Added Figure 28 .............................................................................. 27

Added Figure 29 .............................................................................. 28

Changes to Register Programming Overview Section .............. 28

Changes to DPLL Feedback Dividers Section ............................ 30

Changes to DPLL Phase Lock Detector Section ........................ 35

Change to APLL Calibration Section ........................................... 39

Changes to Table 62 ........................................................................ 73

Added Endnote 1, Table 67 ........................................................... 75

Changes to Table 73, Table 75, and Table 76 ............................... 77

Changes to Table 77, Table 78, Table 79, and Table 80 .............. 78

Changes to Table 82, Table 83, Table 84, Table 85,

and Table 86 ..................................................................................... 79

Changes to Table 87, Table 88, Table 89, and Table 90 .............. 80

Changes to Table 91 and Table 92 ................................................ 82

Changes to Table 94 ........................................................................ 83

Changes to Table 122 ...................................................................... 96

8/2014—Rev. 0 to Rev. A

Added Bandwidth (fREF = 19.44 MHz; fOUT = 156.25 MHz;

fLOOP = 50 Hz) Parameters; Table 18 ............................................. 15

Changes to Figure 3 ........................................................................ 20

Changes to Figure 27 ...................................................................... 31

Changes to APLL Calibration Section ......................................... 36

Changes to Output Amplitude and Power-Down Section ....... 37

Changes to Table 69 ....................................................................... 71

4/2014—Revision 0: Initial Version

Data Sheet AD9554-1

Rev. C | Page 5 of 99

SPECIFICATIONS

Minimum (min) and maximum (max) values apply for the full range of supply voltage and operating temperature variations. Typical (typ)

values apply for VDD = 1.8 V, TA = 25°C, unless otherwise noted.

SUPPLY VOLTAGE

Table 1.

Parameter Min Typ Max Unit

SUPPLY VOLTAGE FOR 1.8 V OPERATION

VDD_SP 1.47 1.8 2.625 V

VDD 1.71 1.8 1.89 V

SUPPLY VOLTAGE FOR 1.5 V OPERATION

VDD_SP 1.47 1.5 2.625 V

VDD 1.47 1.5 1.53 V

SUPPLY CURRENT

The test conditions for the maximum (max) supply current are at the maximum supply voltage found in Table 1. The test conditions for

the typical (typ) supply current are at the typical supply voltage found in Table 1. The test conditions for the minimum (min) supply

current are at the minimum supply voltage found in Table 1.

Table 2.

Parameter Min Typ Max Unit Test Conditions/Comments

SUPPLY CURRENT FOR TYPICAL CONFIGURATION Typical values are for the Typical

Configuration parameter

listed in Table 3; valid for both 1.5 V and 1.8 V

operation

IVDD_SP 0.01 0.04 0.1 mA

IVDD 450 513 560 mA

SUPPLY CURRENT FOR ALL BLOCKS RUNNING CONFIGURATION Maximum values are for the All Blocks

Running parameter

listed in Table 3; valid for both 1.5 V and 1.8 V

operation

IVDD_SP 0.01 0.04 0.1 mA

IVDD 450 566 650 mA

AD9554-1 Data Sheet

Rev. C | Page 6 of 99

POWER DISSIPATION

Typical (typ) values apply for VDD = 1.8 V and maximum (max) values for VDD = 1.89 V.

Table 3.

Parameter Min Typ Max Unit Test Conditions/Comments

POWER DISSIPATION

Typical Configuration 0.92 1.1 W System clock: 49.152 MHz crystal; four DPLLs active;

two 19.44 MHz input references in differential mode;

four ac-coupled output drivers in 21 mA mode at

644.53125 MHz

All Blocks Running 1.02 1.2 W System clock: 49.152 MHz crystal; four DPLLs active,

four 19.44 MHz input references in differential mode;

eight ac-coupled output drivers in 28 mA mode at

750 MHz

Full Power-Down 164 mW Measured using the Typical Configuration parameter

(see Table 3) and then setting the full power down bit

Incremental Power Dissipation Typical configuration; table values show the change in

power due to the indicated operation

Complete DPLL/APLL On/Off 190 mW Power delta computed relative to the typical

configuration; the blocks powered down include one

reference input, one DPLL, one APLL, one P divider, two

channel dividers, two output drivers in 28 mA mode

Input Reference On/Off

Differential (Normal Mode) 22.5 mW fREF = 19.44 MHz

Differential (DC-Coupled LVDS) 24.6 mW fREF = 19.44 MHz

Single-Ended 14.3 mW fREF = 19.44 MHz

Output Distribution Driver On/Off

28 mA Mode (at 644.53 MHz) 70 mW

21 mA Mode (at 644.53 MHz) 48 mW

14 mA mode (at 644.53 MHz) 23.6 mW

SYSTEM CLOCK INPUTS (XOA, XOB)

Table 4.

Parameter Min Typ Max Unit Test Conditions/Comments

SYSTEM CLOCK MULTIPLIER

PLL Output Frequency Range 2250 2415 MHz Voltage controlled oscillator (VCO) range can place

limitations on nonstandard system clock input frequencies

Phase Frequency Detector (PFD) Rate 10 300 MHz

Frequency Multiplication Range 8 241 Assumes valid system clock and PFD rates

SYSTEM CLOCK REFERENCE INPUT PATH System clock input must be ac-coupled

Input Frequency Range

System Clock Input Doubler Disabled 10 268 MHz

System Clock Input Doubler Enabled 16 150 MHz

Minimum Input Slew Rate 250 V/μs Minimum limit imposed for jitter performance

Self-Biased Common-Mode Voltage 0.72 V Internally generated

Input High Voltage 0.9 V For ac-coupled single-ended operation

Input Low Voltage 0.5 V For ac-coupled single-ended operation

Differential Input Voltage Sensitivity 250 mV p-p Minimum voltage across pins required to ensure switching

between logic states; the instantaneous voltage on either

pin must not exceed 1.14 V; single-ended input can be

accommodated by ac grounding complementary input;

800 mV p-p recommended for optimal jitter performance

Data Sheet AD9554-1

Rev. C | Page 7 of 99

Parameter Min Typ Max Unit Test Conditions/Comments

System Clock Input Doubler Duty Cycle Amount of duty-cycle variation that can be tolerated on

the system clock input to use the doubler

System Clock Input = 20 MHz to 150 MHz 43 50 57 %

System Clock Input = 16 MHz to 20 MHz 47 50 53 %

Input Capacitance 3 pF Single-ended to ground, each pin

Input Resistance 5 kΩ

CRYSTAL RESONATOR PATH

Crystal Resonator Frequency Range 12 50 MHz Fundamental mode, AT cut crystal

Input Capacitance 3 pF Single-ended to ground, each pin

Maximum Crystal Motional Resistance 100 Ω

REFERENCE INPUTS

Table 5.

Parameter Min Typ Max Unit Test Conditions/Comments

DIFFERENTIAL MODE AC couple inputs in differential mode

Frequency Range

Sinusoidal Input 10 475 MHz

LVPECL Input 0.002 1000 MHz

LVDS Input 0.002 700 MHz Assumes an LVDS minimum of 494 mV p-p differential

amplitude

Minimum Input Slew Rate Minimum limit imposed for jitter performance

DPLL Loop Bandwidth = 50 Hz 40 V/μs

DPLL Loop Bandwidth = 4 kHz 50 V/μs Maximum loop bandwidth is fPFD/50

Common-Mode Input Voltage 0.64 V Internally generated self-bias voltage

Differential Input Voltage Sensitivity Peak-to-peak differential voltage swing across pins

required to ensure switching between logic levels as

measured with a differential probe; instantaneous voltage

on either pin must not exceed 1.3 V

fIN < 400 MHz 400 2100 mV p-p

fIN = 400 MHz to 750 MHz 500 2100 mV p-p

fIN = 750 MHz to 1000 MHz 1000 2100 mV p-p

Differential Input Voltage Hysteresis 55 100 mV

Input Resistance 16 kΩ Equivalent differential input resistance

Input Capacitance 9 pF Single-ended to ground, each pin

Minimum Pulse Width High

LVPECL 460 ps

LVDS 560 ps

Minimum Pulse Width Low

LVPECL 460 ps

LVDS 560 ps

DC-COUPLED LVDS MODE Intended for dc-coupled LVDS ≤ 10.24 MHz

Frequency Range 0.002 10.24 MHz

Minimum Input Slew Rate Minimum limit imposed for jitter performance

DPLL Loop Bandwidth = 50 Hz 40 V/μs

DPLL Loop Bandwidth = 4 kHz 150 V/μs Maximum loop bandwidth is fPFD/50

Common-Mode Input Voltage 1.125 1.375 V

Differential Input Voltage Sensitivity 400 1200 mV Differential voltage across pins required to ensure

switching between logic levels; instantaneous voltage on

either pin must not exceed the supply rails

Differential Input Voltage Hysteresis 55 100 mV

Input Resistance 21 kΩ

Input Capacitance 7 pF

Minimum Pulse Width High 25 ns

Minimum Pulse Width Low 25 ns

AD9554-1 Data Sheet

Rev. C | Page 8 of 99

Parameter Min Typ Max Unit Test Conditions/Comments

SINGLE-ENDED MODE DC-coupled

Frequency Range (CMOS) 0.002 300 MHz

Minimum Input Slew Rate Minimum limit imposed for jitter performance

DPLL Loop Bandwidth = 50 Hz 40 V/μs

DPLL Loop Bandwidth = 4 kHz 175 V/μs Maximum loop bandwidth is fPFD/50

Input Voltage High, VIH V

DD − 0.5 V

Input Voltage Low, VIL 0.5 V

Input Resistance 30 kΩ

Input Capacitance 5 pF

Minimum Pulse Width High 1.5 ns

Minimum Pulse Width Low 1.5 ns

REFERENCE MONITORS

Table 6.

Parameter Min Typ Max Unit Test Conditions/Comments

REFERENCE MONITORS

Reference Monitor

Loss of Reference Detection Time 1.15 DPLL PFD period Nominal phase detector period = R/fREF, where R is the

frequency division factor determined by the R divider,

and fREF is the frequency of the active reference

Frequency Out-of Range Limits 2 105 Δf/fREF (ppm) Programmable (lower bound subject to quality of the

system clock [SYSCLK]); SYSCLK accuracy must be less

than the lower bound

Validation Timer 0.001 65.535 sec Programmable in 1 ms increments

REFERENCE SWITCHOVER SPECIFICATIONS

Table 7.

Parameter Min Typ Max Unit Test Conditions/Comments

MAXIMUM OUTPUT PHASE PERTURBATION

(PHASE BUILD-OUT SWITCHOVER)

Assumes a jitter-free reference; satisfies

Telcordia GR-1244-CORE requirements; base

loop filter selection bit set to 1b or all active

references

50 Hz DPLL Loop Bandwidth High phase margin mode; 19.44 MHz to

174.70308 MHz; DPLL bandwidth = 50 Hz;

49.152 MHz signal generator used for system

clock source

Peak ±20 ±130 ps

Steady State ±20 ±130 ps

Time Required to Switch to a New Reference

Phase Build-Out Switchover 10 DPLL

PFD

period

Calculated using the nominal phase detector

period (NPDP = R/fREF); the total time required

is the time plus the reference validation time,

plus the time required to lock to the new

reference

Data Sheet AD9554-1

Rev. C | Page 9 of 99

DISTRIBUTION CLOCK OUTPUTS

Table 8.

Parameter Min Typ Max Unit Test Conditions/Comments

14 mA (HCSL-, LVDS-COMPATIBLE) MODE Unless otherwise stated, specifications dc-

coupled with no output termination resistor;

when ac-coupled, LVDS-compatible amplitudes

are achieved with a 100 Ω resistor across the

output pair; HCSL-compatible amplitudes

achieved with no termination resistor across

the output pair; output current setting: 14 mA

Output Frequency 0.430 941 MHz Frequency range all four PLLs can generate using

unique VCO frequencies; frequencies outside

this range are possible on some of the PLLs, but

can result in increased VCO coupling due to

multiple PLLs using the same VCO frequency

Continuous Output Frequency Range 0.430 781 MHz All four PLLs can generate this range at the

same time while using unique VCO frequencies

Maximum Output Frequency

PLL0 to PLL3 Using Unique VCO

Frequencies

941 MHz

Maximum frequency all four PLLs can

generate using unique VCO frequencies

PLL0, PLL1, and PLL2 1250 MHz Limited by 1250 MHz maximum input

frequency to channel divider (Q divider)

PLL3 1187 MHz Limited by 4748 MHz maximum VCO frequency

Rise/Fall Time (20% to 80%)1 125 190 ps

Duty Cycle

Up to fOUT = 750 MHz 45 50 55 %

Up to fOUT = 941 MHz 44 50 56 %

Up to fOUT = 1250 MHz 50 %

Differential Output Voltage Swing

Differential voltage swing between output

pins; measured with output driver static; peak-

to-peak differential output amplitude 2× this

level with driver toggling; see Figure 10 for

output amplitude vs. output frequency

Without 100 Ω Termination Resistor 635 840 1000 mV

With 100 Ω Termination Resistor Across

Outputs

294 390 463 mV

Common-Mode Output Voltage 310 420 525 mV Output driver static; no termination resistor

Reference Input-to-Output Delay Variation

over Temperature

600 fs/°C

DPLL locked to same input reference at all

times; stable system clock source (noncrystal)

Static Phase Offset Variation from Active

Reference to Output over Voltage Extremes

±75 fs/mV

21 mA MODE Unless otherwise stated, specifications

dc-coupled with 50 Ω output termination resistor

to ground; output current setting = 21 mA

Output Frequency 0.430 941 MHz Frequency range all four PLLs can generate using

unique VCO frequencies; frequencies outside

this range are possible on some of the PLLs, but

can result in increased VCO coupling due to

multiple PLLs using the same VCO frequency

Continuous Output Frequency Range 0.430 781 MHz All four PLLs can generate this range at the

same time while using unique VCO frequencies

Maximum Output Frequency

PLL0 to PLL3 Using Unique VCO

Frequencies

941 MHz

Maximum frequency all four PLLs can

generate using unique VCO frequencies

PLL0, PLL1, and PLL2 1250 MHz Limited by 1250 MHz maximum input

frequency to channel divider (Q divider)

PLL3 1187 MHz Limited by 4748 MHz maximum VCO frequency

AD9554-1 Data Sheet

Rev. C | Page 10 of 99

Parameter Min Typ Max Unit Test Conditions/Comments

Rise/Fall Time (20% to 80%)1 125 190 ps

Duty Cycle

Up to fOUT = 750 MHz 45 50 55 %

Up to fOUT = 941 MHz 44 50 56 %

Up to fOUT = 1250 MHz 50 %

Differential Output Voltage Swing

Differential voltage swing between output

pins; measured with output driver static; peak-

to-peak differential output amplitude 2× this

level with driver toggling; see Figure 12 for

output amplitude vs. output frequency

No External Termination Resistor 779 1180 1510 mV

With 50 Ω Termination Resistor to

Ground on Each Leg

413 625 800 mV

Common-Mode Output Voltage 206 312 400 mV Output driver static with 50 Ω resistor to

ground on each leg

Reference Input-to-Output Delay Variation

over Temperature

600 fs/°C

DPLL locked to same input reference at all

times; stable system clock source (noncrystal)

Static Phase Offset Variation from Active

Reference to Output over Voltage Extremes

±75 fs/mV

28 mA (LVPECL-COMPATIBLE) MODE Specifications for dc-coupled, 50 Ω termination

resistor from each leg to ground; ac coupling

used in most applications; output current

setting = 28 mA; in this mode, user must have

either a 50 Ω resistor from each leg to ground,

or a 100 Ω resistor across the differential pair

Output Frequency 0.430 941 MHz Frequency range all four PLLs can generate using

unique VCO frequencies; frequencies outside

this range are possible on some of the PLLs, but

can result in increased VCO coupling due to

multiple PLLs using the same VCO frequency

Continuous Output Frequency Range 0.430 781 MHz Frequency range for each PLL such that all four

PLLs are using unique VCO frequencies with

no frequency gaps

Maximum Output Frequency

PLL0 to PLL3 Using Unique VCO

Frequencies

941 MHz

Maximum frequency all four PLLs can

generate using unique VCO frequencies

PLL0, PLL1, and PLL2 1250 MHz Limited by 1250 MHz maximum input

frequency to channel divider (Q divider)

PLL3 1187 MHz Limited by 4748 MHz maximum VCO frequency

Rise/Fall Time (20% to 80%)1 185 280 ps

Duty Cycle

Up to fOUT = 750 MHz 45 50 55 %

Up to fOUT = 941 MHz 44 50 56 %

Up to fOUT = 1250 MHz 50 %

Differential Output Voltage Swing 540 830 1020 mV

Differential voltage swing between output

pins; measured with output driver static; peak-

to-peak differential output amplitude 2× this

level with driver toggling; see Figure 9 for

output amplitude vs. output frequency

Common-Mode Output Voltage 275 415 510 mV Output driver static; 50 Ω external termination

resistor from each leg to ground

Reference Input-to-Output Delay Variation

over Temperature

600 fs/°C

DPLL locked to same input reference at all

times; stable system clock source (noncrystal)

Static Phase Offset Variation from Active

Reference to Output over Voltage Extremes

±75 fs/mV

1 The listed values are for the slower edge (rising or falling).

Data Sheet AD9554-1

Rev. C | Page 11 of 99

TIME DURATION OF DIGITAL FUNCTIONS

Table 9.

Parameter Min Typ Max Unit Test Conditions/Comments

TIME DURATION OF DIGITAL FUNCTIONS

Power-Down Exit Time 51 ms Time from power-down exit to system clock stable (including

the system clock stability timer default of 50 ms); does not

include time to validate input references or lock the DPLL

Mx Pin to RESET Rising Edge Setup Time 1 ns Mx refers to the M0, M1, M2, M3, M5, M6, M7 pins

Mx Pin to RESET Rising Edge Hold Time 1 ns

RESET Falling Edge to Mx Pin High-Z Time 10 ns

DIGITAL PLL (DPLL_0, DPLL_1, DPLL_2, AND DPLL_3)

Table 10.

Parameter Min Typ Max Unit Test Conditions/Comments

DIGITAL PLL

Phase Frequency Detector (PFD)

Input Frequency Range

2 200 kHz

Loop Bandwidth 0.1 4000 Hz Programmable design parameter; note that (fPFD/loop bandwidth) ≥ 50

Phase Margin 45 89 Degrees Programmable design parameter

Closed Loop Peaking <0.1 dB Programmable design parameter; part can be programmed for

<0.1 dB peaking in accordance with Telcordia GR-253-CORE jitter transfer

ANALOG PLL (APLL_0, APLL_1, APLL_2, AND APLL_3)

Table 11.

Parameter Min Typ Max Unit Test Conditions/Comments

ANALOG PLL0 (APLL_0)

VCO Frequency Range 2424 3132 MHz

Phase Frequency Detector (PFD)

Input Frequency Range

320 350 MHz

The AD9554-1 evaluation software finds the optimal value

for this setting based on user’s input.

Loop Bandwidth 240 kHz

Phase Margin 68 Degrees

ANALOG PLL1 (APLL_1)

VCO Frequency Range 3232 3905 MHz

Phase Frequency Detector (PFD)

Input Frequency Range

320 350 MHz

The AD9554-1 evaluation software finds the optimal value

for this setting based on user’s input.

Loop Bandwidth 240 kHz

Phase Margin 68 Degrees

ANALOG PLL2 (APLL_2)

VCO Frequency Range 4842 5650 MHz

Phase Frequency Detector (PFD)

Input Frequency Range

320 350 MHz

The AD9554-1 evaluation software finds the optimal value

for this setting based on user’s input.

Loop Bandwidth 240 kHz

Phase Margin 68 Degrees

ANALOG PLL3 (APLL_3)

VCO Frequency Range 4040 4748 MHz

Phase Frequency Detector (PFD)

Input Frequency Range

320 350 MHz

The AD9554-1 evaluation software finds the optimal value

for this setting based on user’s input.

Loop Bandwidth 240 kHz

Phase Margin 68 Degrees

AD9554-1 Data Sheet

Rev. C | Page 12 of 99

DIGITAL PLL LOCK DETECTION

Table 12.

Parameter Min Typ Max Unit Test Conditions/Comments

PHASE LOCK DETECTOR

Threshold Programming Range 10 224 − 1 ps Reference-to-feedback phase difference

Threshold Resolution 1 ps

FREQUENCY LOCK DETECTOR

Threshold Programming Range 10 224 − 1 ps Reference-to-feedback period difference

Threshold Resolution 1 ps

HOLDOVER SPECIFICATIONS

Table 13.

Parameter Min Typ Max Unit Test Conditions/Comments

HOLDOVER SPECIFICATIONS

Initial Frequency Accuracy <0.01 ppm Excludes frequency drift of SYSCLK source; excludes

frequency drift of input reference prior to entering

holdover; compliant with GR-1244 Stratum 3

SERIAL PORT SPECIFICATIONS—SERIAL PORT INTERFACE (SPI) MODE

Table 14.

Parameter Min Typ Max Unit Test Conditions/Comments

CS Valid for VDD_SP = 1.5 V, VDD_SP = 1.8 V, and VDD_SP = 2.5 V

Input Logic 1 Voltage VDD_SP − 0.4 V

Input Logic 0 Voltage 0.4 V

Input Logic 1 Current 1 μA

Input Logic 0 Current 1 μA

Input Capacitance 3 pF

SCLK No internal pull-up or pull-down resistor

Input Logic 1 Voltage VDD_SP − 0.4 V

Input Logic 0 Voltage 0.4 V

Input Logic 1 Current 1 μA

Input Logic 0 Current 1 μA

Input Capacitance 2 pF

SDIO

As an Input

Input Logic 1 Voltage VDD_SP − 0.4 V

Input Logic 0 Voltage 0.4 V

Input Logic 1 Current 1 μA

Input Logic 0 Current 1 μA

Input Capacitance 2 pF

As an Output

Output Logic 1 Voltage VDD_SP − 0.2 V 1 mA load current

Output Logic 0 Voltage 0.1 V 1 mA load current

Data Sheet AD9554-1

Rev. C | Page 13 of 99

Parameter Min Typ Max Unit Test Conditions/Comments

TIMING Valid for VDD_SP = 1.5 V, VDD_SP = 1.8 V, and VDD_SP = 2.5 V

SCLK

Clock Rate, 1/tCLK 50 MHz

Pulse Width High, tHIGH 5 ns

Pulse Width Low, tLOW 8 ns

SDIO to SCLK Setup, tDS 1.5 ns

SCLK to SDIO Hold, tDH 0 ns

SCLK to Valid SDIO, tDV 8 ns

CS to SCLK Setup, tS 0 ns

CS to SCLK Hold, tC 0 ns

CS Minimum Pulse Width High 1.5 ns

SERIAL PORT SPECIFICATIONS—I2C MODE

Table 15.

Parameter Min Typ Max Unit Test Conditions/Comments

SDA, SCL (AS INPUTS) Valid for VDD_SP = 1.5 V,

VDD_SP = 1.8 V, and VDD_SP

= 2.5 V

Input Logic 1 Voltage 0.7 × VDD_SP V

Input Logic 0 Voltage 0.3 × VDD_SP V

Input Current −10 +10 μA For VIN = 10% to 90% of VDD

Hysteresis of Schmitt Trigger Inputs 0.015 × VDD

SDA (AS OUTPUT)

Output Logic 0 Voltage 0.2 V IOUT = 3 mA

Output Fall Time from VIH Minimum to VIL Maximum 20 + 0.1 × Cb 250 ns 10 pF ≤ Cb ≤ 400 pF

TIMING

SCL Clock Rate 400 kHz

Bus-Free Time Between a Stop and Start Condition, tBUF 1.3 μs

Repeated Start Condition Setup Time, tSU; STA 0.6 μs

Repeated Hold Time Start Condition, tHD; STA 0.6 μs

After this period, the first

clock pulse is generated

Stop Condition Setup Time, tSU; STO 0.6 μs

Low Period of the SCL Clock, tLOW 1.3 μs

High Period of the SCL Clock, tHIGH 0.6 μs

SCL/SDA Rise Time, tR 20 + 0.1 × Cb 300 ns

SCL/SDA Fall Time, tF 20 + 0.1 × Cb 300 ns

Data Setup Time, tSU; DAT 100 ns

Data Hold Time, tHD; DAT 100 ns

Capacitive Load for Each Bus Line, Cb 400 pF

AD9554-1 Data Sheet

Rev. C | Page 14 of 99

LOGIC INPUTS (RESET, M0 TO M3, M5 TO M7)

Table 16.

Parameter Min Typ Max Unit Test Conditions/Comments

RESET PIN Valid for VDD_SP = 1.5 V, VDD_SP = 1.8 V, and VDD_SP = 2.5 V

Input High Voltage (VIH) VDD_SP −0.5 V

Input Low Voltage (VIL) 0.5 V

Input Current (IINH, IINL) ±85 ±125 μA

Input Capacitance (CIN) 3 pF

LOGIC INPUTS (M0 TO M3 AND M5 TO M7) Valid for VDD = 1.5 V, and VDD = 1.8 V

Input High Voltage (VIH) VDD − 0.5 V

Input Low Voltage (VIL) 0.6 V

Input Current (IINH, IINL) ±15 ±25 μA

Input Capacitance (CIN) 5 pF

LOGIC OUTPUTS (M0 TO M3 AND M5 TO M7)

Table 17.

Parameter Min Typ Max Unit Test Conditions/Comments

LOGIC OUTPUTS (M0 to M3 and M5 to M7) VDD = 1.5 V and VDD = 1.8 V

Output High Voltage (VOH) VDD − 0.2 V IOH = 1 mA using high drive strength (see Register 0x011E)

Output Low Voltage (VOL) 0.2 V IOL = 1 mA

JITTER GENERATION

Jitter Generation (Random Jitter)—49.152 MHz Crystal for System Clock Input

Table 18.

Parameter Min Typ Max Unit Test Conditions/Comments

JITTER GENERATION System clock doubler enabled; high phase margin

mode enabled; all PLLs are running with same

output frequency; in cases where the four PLLs

have different jitter, the higher jitter is listed; there

is not a significant jitter difference between driver

modes

fREF = 19.44 MHz; fOUT = 622.08 MHz; fLOOP = 50 Hz

Bandwidth

5 kHz to 20 MHz 381 fs rms

12 kHz to 20 MHz 375 fs rms

20 kHz to 80 MHz 380 fs rms

50 kHz to 80 MHz 365 fs rms

4 MHz to 80 MHz 116 fs rms

fREF = 19.44 MHz; fOUT = 644.53 MHz; fLOOP = 50 Hz

Bandwidth

5 kHz to 20 MHz 388 fs rms

12 kHz to 20 MHz 381 fs rms

20 kHz to 80 MHz 385 fs rms

50 kHz to 80 MHz 368 fs rms

4 MHz to 80 MHz 106 fs rms

fREF = 19.44 MHz; fOUT = 693.48 MHz; fLOOP = 50 Hz

Bandwidth

5 kHz to 20 MHz 433 fs rms

12 kHz to 20 MHz 427 fs rms

20 kHz to 80 MHz 432 fs rms

50 kHz to 80 MHz 419 fs rms

4 MHz to 80 MHz 120 fs rms

Data Sheet AD9554-1

Rev. C | Page 15 of 99

Parameter Min Typ Max Unit Test Conditions/Comments

fREF = 19.44 MHz; fOUT = 156.25 MHz; fLOOP = 50 Hz

Bandwidth

5 kHz to 20 MHz 420 fs rms

12 kHz to 20 MHz 414 fs rms

20 kHz to 80 MHz 461 fs rms

50 kHz to 80 MHz 449 fs rms

4 MHz to 80 MHz 260 fs rms

fREF = 19.44 MHz; fOUT = 174.703 MHz; fLOOP = 50 Hz

Bandwidth

5 kHz to 20 MHz 398 fs rms

12 kHz to 20 MHz 393 fs rms

20 kHz to 80 MHz 439 fs rms

50 kHz to 80 MHz 427 fs rms

4 MHz to 80 MHz 231 fs rms

fREF = 25 MHz; fOUT = 161.1328 MHz; fLOOP = 100 Hz

Bandwidth

5 kHz to 20 MHz 385 fs rms

12 kHz to 20 MHz 379 fs rms

20 kHz to 80 MHz 423 fs rms

50 kHz to 80 MHz 412 fs rms

4 MHz to 80 MHz 250 fs rms

AD9554-1 Data Sheet

Rev. C | Page 16 of 99

ABSOLUTE MAXIMUM RATINGS

Table 19.

Parameter Rating

1.8 V Supply Voltage (VDD) 2 V

Serial Port Supply Voltage (VDD_SP) 2.75 V

Maximum Digital Input Voltage Range −0.5 V to VDD + 0.5 V

Storage Temperature Range −65°C to +150°C

Operating Temperature Range −40°C to +85°C

Lead Temperature (Soldering 10 sec) 300°C

Junction Temperature 115°C

Stresses at or above those listed under Absolute Maximum

Ratings may cause permanent damage to the product. This is a

stress rating only; functional operation of the product at these

or any other conditions above those indicated in the operational

section of this specification is not implied. Operation beyond

the maximum operating conditions for extended periods may

affect product reliability.

ESD CAUTION

Data Sheet AD9554-1

Rev. C | Page 17 of 99

PIN CONFIGURATION AND FUNCTION DESCRIPTIONS

OUT3B

VDD

REFD

VDD

REFA

VDD

OUT0B

VDD

LDO_0

LF_0

VDD

SDIO/SDA

SCLK/SCL

VDD_SP

RESET

LF_1

LDO_1

VDD

OUT2B

VDD

REFC

VDD

REFB

VDD

OUT1B

VDD

LDO_3

LF_3

XOA

XOB

VDD

LF_2

LDO_2

VDD

AD9554-1

TOP VIEW

(Not to Scale)

NOTES

1. THE EXPOSED PAD IS THE GROUND CONNECTION ON THE CHIP. IT

MUST BE SOLDERED TO THE ANALOG GROUND OF THE PCB TO

ENSURE PROPER FUNCTIONALITY AND HEAT DISSIPATION, NOISE,

AND MECHANICAL STRENGTH BENEFITS.

OUT3B OUT2B

OUT1B

OUT0B

12214-002

Figure 2. Pin Configuration

Table 20. Pin Function Descriptions

Pin No. Mnemonic

Input/

Output Pin Type Description

1 OUT3B O

HCSL, LVDS-

compatible,

LVPECL-

compatible

PLL3 Output 3B. This HCSL output can be configured as a LVDS- or a LVPECL-

compatible output. LVPECL and LVDS levels can be achieved by ac-coupling

and using the Thevenin equivalent termination as described in the Input/Output

Termination Recommendations section.

2 OUT3B O HCSL, LVDS-

compatible,

LVPECL-

compatible

PLL3 Complementary Output 3B. Complementary signal to the output

provided on Pin 1 (OUT3B).

3, 7, 8, 12, 15,

16, 19, 27, 28,

31, 35, 36, 40,

43, 44, 49, 55,

VDD I Power

1.5 V or 1.8 V Power Supply. See the Power Supply Partitions section for

information about the recommended grouping of the power supply pins.

4, 11, 32, 39 M3, M0, M1,

I/O 1.5 V/1.8 V

CMOS

Configurable Input/Output Pins. These pins are used for status and control of

the AD9554-1. See the Multifunction Pins at Reset/Power-Up section for more

information about the internal 100 kΩ pull-up or pull-down resistors. These

pins are on the VDD power domain (Pin 7, Pin 8, Pin 35, and Pin 36), and the

logic high voltage for this pin matches the voltage of the VDD pins.

5 REFD I

Differential

input

Reference D Input. This internally biased input is typically ac-coupled; when

configured in this manner, it can accept any differential signal with single-

ended swing up to the VDD power supply. If dc-coupled, the input can be

LVDS or single-ended CMOS provided that VIH ≤ VDD.

6 REFD I Differential

input

Complementary Reference D Input. Complementary signal to the input

provided on Pin 5 (REFD). This pin can be left floating if REFD is a single-ended

input, or if REFD is not used.

9 REFA I Differential

input

Complementary Reference A Input. Complementary signal to the input

provided on Pin 10 (REFA). This pin can be left floating if REFA is a single-ended

input or if REFA is not used.

AD9554-1 Data Sheet

Rev. C | Page 18 of 99

Pin No. Mnemonic

Input/

Output Pin Type Description

10 REFA I

Differential

input

Reference A Input. This internally biased input is typically ac-coupled; when

configured in this manner, it can accept any differential signal with single-

ended swing up to the VDD power supply. If dc-coupled, the input can be

LVDS, or single-ended CMOS provided that VIH ≤ VDD.

13 OUT0B O HCSL, LVDS-

compatible,

LVPECL-

compatible

PLL0 Complementary Output 0B. Complementary signal to the output

provided on Pin 14 (OUT0B).

14 OUT0B O

HCSL, LVDS-

compatible,

LVPECL-

compatible

PLL0 Output 0B. This HCSL output can be configured as a LVDS- or a LVPECL-

compatible output. LVPECL and LVDS levels can be achieved by ac-coupling

and using the Thevenin equivalent termination as described in the Input/Output

Termination Recommendations section.

17 LDO_0 I LDO bypass

APLL_0 Loop Filter Voltage Regulator. Connect a 0.22 μF capacitor from this pin

to ground. This pin is also the ac ground reference for the integrated APLL_0

external loop filter.

18 LF_0 I/O

Loop filter for

APLL_0

Loop Filter Node for the APLL_0. Connect an external 15 nF capacitor from this

pin to Pin 17 (LDO_0).

20 SDIO/SDA I/O CMOS

Serial Data Input/Output (SDIO) in SPI Mode. In 4-wire SPI mode, data is written

via this pin. In 3-wire SPI mode, data reads and writes both occur on this pin.

Serial Data Pin (SDA) in I2C Mode. There is no internal pull-up/pull-down

resistor on this pin. The VIH/VOH of this pin tracks the VDD_SP power supply

(which can be 1.5 V, 1.8 V, or 2.5 V).

21 SCLK/SCL I CMOS

Serial Programming Clock (SCLK) in SPI Mode. In I2C mode, this is the serial

clock pin (SCL). The VIH/VOH of this pin tracks the VDD_SP power supply (which

can be 1.5 V, 1.8 V, or 2.5 V).

22 CS I/O CMOS Chip Select in SPI Mode (CS). Active low input. When programming a device in

SPI, this pin must be held low. In systems where more than one AD9554-1 is

present, this pin enables individual programming of each AD9554-1. This pin

has an internal 10 kΩ pull-up resistor. The VIH/VOH of this pin tracks the VDD_SP

power supply (which can be 1.5 V, 1.8 V, or 2.5 V).

23 VDD_SP I Power

Serial Port Power Supply. The power supply can be 1.5 V, 1.8 V, or 2.5 V. If this

pin is at the same voltage as VDD, it can connected to VDD pins. See the Power

Supply Partitions section for information about the recommended grouping of

the power supply pins.

24 RESET I CMOS logic

Chip Reset. When this active low pin is asserted, the chip goes into reset. This

pin has an internal 50 kΩ pull-up resistor.

25 LF_1 I/O

Loop filter for

APLL_1

Loop Filter Node for the APLL_1. Connect an external 15 nF capacitor from this

pin to Pin 26 (LDO_1).

26 LDO_1 I LDO bypass

APLL_1 Loop Filter Voltage Regulator. Connect a 0.22 μF capacitor from this pin

to ground. This pin is also the ac ground reference for the integrated APLL_1

external loop filter.

29 OUT1B O

HCSL, LVDS-

compatible,

LVPECL-

compatible

PLL1 Output 1B. This HCSL output can be configured as a LVDS- or a LVPECL-

compatible. LVPECL and LVDS levels can be achieved by ac-coupling and using

the Thevenin equivalent termination as described in the Input/Output

Termination Recommendations section.

30 OUT1B O HCSL, LVDS-

compatible,

LVPECL-

compatible

PLL1 Complementary Output 1B. Complementary signal to the output

provided on Pin 29 (OUT1B).

33 REFB I

Differential

input

Reference B Input. This internally biased input is typically ac-coupled; when

configured in this manner, it can accept any differential signal with single-

ended swing up to the VDD power supply. If dc-coupled, the input can be

LVDS, or single-ended CMOS provided that VIH ≤ VDD.

34 REFB I Differential

input

Complementary Reference B Input. Complementary signal to the input

provided on Pin 33 (REFB). This pin can be left floating if REFB is a single-ended

input or if REFB is not used.

37 REFC I Differential

input

Complementary Reference C Input. Complementary signal to the input

provided on Pin 38 (REFC). This pin can be left floating if REFC is a single-ended

input or if REFC is not used.

Data Sheet AD9554-1

Rev. C | Page 19 of 99

Pin No. Mnemonic

Input/

Output Pin Type Description

38 REFC I

Differential

input

Reference C Input. This internally biased input is typically ac-coupled; when

configured in this manner, it can accept any differential signal with single-

ended swing up to the VDD power supply. If dc-coupled, the input can be

LVDS, or single-ended CMOS provided that VIH ≤ VDD.

41 OUT2B O HCSL, LVDS-

compatible,

LVPECL-

compatible

PLL2 Complementary Output 2B. Complementary signal to the output

provided on Pin 42 (OUT2B).

42 OUT2B O

HCSL, LVDS-

compatible,

LVPECL-

compatible

PLL2 Output 2B. This HCSL output can be configured as a LVDS- or a LVPECL-

compatible. LVPECL and LVDS levels can be achieved by ac-coupling and using

the Thevenin equivalent termination as described in the Input/Output

Termination Recommendations section.

45 LDO_2 I LDO bypass

APLL_2 Loop Filter Voltage Regulator. Connect a 0.22 μF capacitor from this pin

to ground. This pin is also the ac ground reference for the integrated APLL_2

external loop filter.

46 LF_2 I/O

Loop filter for

APLL_2

Loop Filter Node for the APLL_2. Connect an external 15 nF capacitor from this

pin to Pin 45 (LDO_2).

47, 48, 52 M5, M6, M7 I/O 1.5 V/1.8 V

CMOS

Configurable Input/Output Pins. These pins are used for status and control of

the AD9554-1. These pins are also used at power-up and reset to determine

the serial port and address. See the Multifunction Pins at Reset/Power-Up

section for more information about the internal 100 kΩ pull-up or pull-down

resistors. These pins are on the VDD digital power domain (Pin 49), and the

logic high voltage for this pin matches the voltage of the VDD pins.

50 XOB I

Differential

input

Complementary System Clock Input. Complementary signal to XOA. XOB

contains internal dc biasing and must be ac-coupled with a 0.1 μF capacitor

except when using a crystal. When a crystal is used, connect the crystal across

XOA and XOB.

51 XOA I

Differential

input

System Clock Input. XOA contains internal dc biasing and must be ac-coupled

with a 0.1 μF capacitor except when using a crystal. When a crystal is used,

connect the crystal across XOA and XOB. Single-ended CMOS is also an option,

but a spur may be introduced if the duty cycle is not 50%. When using XOA as

a single-ended input, connect a 0.1 μF capacitor from XOB to ground.

53 LF_3 I/O

Loop filter for

APLL_3

Loop Filter Node for the APLL_3. Connect an external 15 nF capacitor from this

pin to Pin 54 (LDO_3).

54 LDO_3 I LDO bypass

APLL_3 Loop Filter Voltage Regulator. Connect a 0.22 μF capacitor from this pin

to ground. This pin is also the ac ground reference for the integrated APLL_3

external loop filter.

57 EPAD GND Exposed pad

The exposed pad is the ground connection on the chip. It must be soldered to

the analog ground of the printed circuit board (PCB) to ensure proper

functionality and heat dissipation, noise, and mechanical strength benefits.

AD9554-1 Data Sheet

Rev. C | Page 20 of 99

TYPICAL PERFORMANCE CHARACTERISTICS

fR = input reference clock frequency, fOUT = output clock frequency, fSYS = SYSCLK input frequency, and VDD at 1.8 V.

–160

–150

–140

–130

–120

–110

–100

–90

–80

–70

–

PHASE NOISE (dBc/Hz)

FREQUENCY OFFSET (Hz)

1k10 100 10k 100k 1M 10M 100M

INTEGRATED RMS JITTER

(12kHz TO 20MHz): 375fs

PHASE NOISE (dBc/Hz):

10Hz –69

100Hz –84

1kHz –102

10kHz –113

100kHz –113

1MHz –127

10MHz –146

FLOOR –152

12132-302

Figure 3. Absolute Phase Noise (Output Driver = 21 mA Mode),

fR = 19.44 MHz, fOUT = 622.08 MHz,

DPLL Loop Bandwidth = 50 Hz, fSYS = 49.152 MHz Crystal

–160

–150

–140

–130

–120

–110

–100

–90

–80

–70

–

PHASE NOISE (dBc/Hz)

FREQUENCY OFFSET (Hz)

1k10 100 10k 100k 1M 10M 100M

INTEGRATED RMS JITTER

(12kHz TO 20MHz): 381fs

PHASE NOISE (dBc/Hz):

10Hz –67

100Hz –84

1kHz –102

10kHz –113

100kHz –116

1MHz –128

10MHz –147

FLOOR –152

12132-303

Figure 4. Absolute Phase Noise (Output Driver = 21 mA Mode),

fR = 19.44 MHz, fOUT = 644.53125 MHz,

DPLL Loop Bandwidth = 50 Hz, fSYS = 49.152 MHz Crystal

–160

–150

–140

–130

–120

–110

–100

–90

–80

–70

–

PHASE NOISE (dBc/Hz)

FREQUENCY OFFSET (Hz)

1k10 100 10k 100k 1M 10M 100M

INTEGRATED RMS JITTER

(12kHz TO 20MHz): 427fs

PHASE NOISE (dBc/Hz):

10Hz –63

100Hz –84

1kHz –101

10kHz –112

100kHz –116

1MHz –124

10MHz –144

FLOOR –151

12132-304

Figure 5. Absolute Phase Noise (Output Driver = 21 mA Mode),

fR = 19.44 MHz, fOUT = 693.482991 MHz,

DPLL Loop Bandwidth = 50 Hz, fSYS = 49.152 MHz Crystal

–160

–150

–140

–130

–120

–110

–100

–90

–80

–70

–

PHASE NOISE (dBc/Hz)

FREQUENCY OFFSET (Hz)

1k10 100 10k 100k 1M 10M 100M

INTEGRATED RMS JITTER

(12kHz TO 20MHz): 393fs

PHASE NOISE (dBc/Hz):

10Hz –80

100Hz –96

1kHz –113

10kHz –125

100kHz –128

1MHz –137

10MHz –154

FLOOR –155

12132-307

Figure 6. Absolute Phase Noise (Output Driver = 21 mA Mode),

fR = 19.44 MHz, fOUT = 174.703 MHz,

DPLL Loop Bandwidth = 1 kHz, fSYS = 49.152 MHz Crystal

–160

–150

–140

–130

–120

–110

–100

–90

–80

–70

–

PHASE NOISE (dBc/Hz)

FREQUENCY OFFSET (Hz)

1k10 100 10k 100k 1M 10M 100M

INTEGRATED RMS JITTER

(12kHz TO 20MHz): 379fs

PHASE NOISE (dBc/Hz):

10Hz –80

100Hz –96

1kHz –114

10kHz –125

100kHz –129

1MHz –139

10MHz –154

FLOOR –155

12132-308

Figure 7. Absolute Phase Noise, fR = 19.44 MHz, fOUT = 161.1328125 MHz,

DPLL Loop Bandwidth = 100 Hz, fSYS = 49.152 MHz Crystal

–160

–150

–140

–130

–120

–110

–100

–90

–80

–70

–

PHASE NOISE (dBc/Hz)

FREQUENCY OFFSET (Hz)

1k10 100 10k 100k 1M 10M 100M

INTEGRATED RMS JITTER

(12kHz TO 20MHz): 408fs

PHASE NOISE (dBc/Hz):

OFFSET LEVEL

10Hz –79

100Hz –82

1kHz –110

10kHz –127

100kHz –131

1MHz –141

10MHz –153

FLOOR –154

12132-008

Figure 8. Absolute Phase Noise (Output Driver = 14 mA Mode), fR = 2 kHz,

fOUT = 125 MHz, DPLL Loop Bandwidth = 100 Hz, fSYS = 49.152 MHz Crystal

Data Sheet AD9554-1

Rev. C | Page 21 of 99

1.8

1.6

1.4

1.2

1.0

0.8

0.6

0.4

0.2

0 1000900800700600500400300200100

12132-316

WITH 100Ω TERMINATION RESISTOR (REQUIRED)

OUTPUT FREQUENCY (MHz)

PEAK-TO-PEAK DIFFERENTIAL AMPLITUDE (V)

Figure 9. Peak-to-Peak Differential Amplitude vs. Output Frequency, 28 mA Mode

(LVPECL-Compatible Mode) with 100 Ω Termination Resistor (Required)

1.8

1.6

1.4

1.2

1.0

0.8

0.6

0.4

0.2

0 1000900800700600500400300200100

12132-318

OUTPUT FREQUENCY (MHz)

PEAK-TO-PEAK DIFFERENTIAL AMPLITUDE (V)

NO TERMINATION RESISTOR (HCSL)

100Ω TERMINATION (LVDS COMPATIBLE)

Figure 10. Peak-to-Peak Differential Amplitude vs. Output Frequency,

14 mA Mode

1.8

1.6

1.4

1.2

1.0

0.8

0.6

0.4

0.2

SINGLE-ENDED PEAK-TO-PEAK AMPLITUDE (V)

OUTPUT FREQUENCY (MHz)

0 100 200 300 400 500 600 700 800 900 1000

12132-312

SINGLE-ENDED, NO TERMINATION

Figure 11. Single-Ended Peak-to-Peak Amplitude vs. Output Frequency,

21 mA Mode (No Termination)

3.0

2.5

2.0

1.5

1.0

0.5

0 1000900800700600500400300200100

12132-317

OUTPUT FREQUENCY (MHz)

PEAK-TO-PEAK DIFFERENTIAL AMPLITUDE (V)

NO TERMINATION RESISTOR

100Ω TERMINATION RESISTOR

Figure 12. Peak-to-Peak Differential Amplitude vs. Output Frequency,

21 mA Mode

–1.0

1.0

0.8

0.6

0.4

0.2

–0.2

–0.4

–0.6

–0.8

054321

12132-400

TIME (ns)

OUTPUT (V)

Figure 13. Output Waveform, 28 mA LVPECL-Compatible Mode (400 MHz)

with 100 Ω Termination Resistor

–0.8

–0.7

–0.6

–0.5

–0.4

–0.3

–0.2

–0.1

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

054321

12132-401

TIME (ns)

OUTPUT (V)

Figure 14. Output Waveform, 21 mA Mode (400 MHz)

with 100 Ω Termination at Load

AD9554-1 Data Sheet

Rev. C | Page 22 of 99

–0.6

–0.5

–0.4

–0.3

–0.2

–0.1

0.1

0.2

0.3

0.4

0.5

0.6

054321

12132-402

TIME (ns)

OUTPUT (V)

Figure 15. Output Waveform, 14 mA LVDS-Compatible Mode (400 MHz)

with 100 Ω Termination at Load

–1.6

–1.4

–1.2

–1.0

–0.8

–0.6

–0.4

–0.2

1.4

1.2

1.0

0.8

0.6

0.4

0.2

1.6

0252015105

12132-403

TIME (ns)

OUTPUT (V)

NO TERMINATION

100Ω TERMINATION

Figure 16. Output Waveform, 21 mA Mode (100 MHz)

–1.2

–1.0

–0.8

–0.6

–0.4

–0.2

1.0

0.8

0.6

0.4

0.2

1.2

0252015105

12132-404

TIME (ns)

OUTPUT (V)

NO TERMINATION

100Ω TERMINATION

Figure 17. Output Waveform, 14 mA Mode (100 MHz)

–30

–27

–24

–21

–18

–15

–12

–9

–6

–3

10 100 1k 10k 100k

OFFSET FREQUENCY (Hz)

LOOP GAIN (dB)

12132-129

LOOP BW = 100Hz

LOOP BW = 2kHz

LOOP BW = 4kHz

Figure 18. Closed-Loop Transfer Function for 100 Hz, 2 kHz, and 4 kHz Loop

Bandwidth Settings; High Phase Margin Loop Filter Setting;

Figure Compliant with Telcordia GR-253 Jitter Transfer Test for

Loop Bandwidths <2 kHz (The Bandwidth Register Setting is the Point Where

the Open-Loop Gain = 0 dB)

–30

–27

–24

–21

–18

–15

–12

–9

–6

–3

10 100 1k

OFFSET FREQUENCY (Hz)

LOOP GAIN (dB)

10k 100k

12132-230

LOOP BW = 100Hz

PEAKING: 1.3dB. –3dB: 112Hz

LOOP BW = 2kHz

PEAKING: 1.1dB. –3dB: 2.4kHz

LOOP BW = 4kHz.

PEAKING: 1.1dB. –3dB: 5.3kHz

Figure 19. Closed-Loop Transfer Function for 100 Hz, 2 kHz, and 4 kHz Loop

Bandwidth Settings; Normal Phase Margin Loop Filter Setting (The

Bandwidth Register Setting is The Point Where the Open-Loop Gain = 0 dB)

Data Sheet AD9554-1

Rev. C | Page 23 of 99

INPUT/OUTPUT TERMINATION RECOMMENDATIONS

AD9554-1

DOWNSTREAM

DEVICE

WITH HIGH

IMPEDANCE

INPUT AND

INTERNAL

DC BIAS

0.1µF

100Ω

= 50Ω

SINGLE-ENDED

(NOT

CLOSE-COUPLED)

12214-130

Figure 20. Destination Self-Biased Differential Receiver; Use 14 mA Mode for

LVDS-Compatible Amplitude or 28 mA for LVPECL-Compatible Amplitudes

(100 Ω Resistor Must be as Close to the Destination Receiver as Possible)

AD9554-1

14mA

MODE

= 50Ω

SINGLE-ENDED

(NOT CLOSE-COUPLED)

HCSL

HIGH IMPEDANCE

DIFFERENTIAL

RECEIVER

12214-131

Figure 21. DC-Coupled HCSL Receiver

SINGLE-ENDED

(NOT COUPLED)

= 3.3V

3.3V

LVPECL

82Ω82Ω

127Ω127Ω

0.1µF

AD9554-1

28mA

MODE

= 50Ω

12214-132

Figure 22. Interfacing the HCSL Driver to a 3.3 V LVPECL Input

(This method incorporates impedance matching and dc-biasing for bipolar

LVPECL receivers. If the receiver is self-biased, the termination scheme shown

in Figure 20 is recommended)

XOA

XOB

AD9554-1

12MHz TO 50MHz FUNDAMENTAL

AT-CUT CRYSTAL WITH 10pF

LOAD CAPACITANCE (C

LOAD

)

15pF

12214-133

Figure 23. System Clock Input (XOA/XOB) in Crystal Mode

(The Recommended CLOAD = 10 pF is Shown. The 15 pF shunt Capacitors

Shown in This Figure Must Equal 2 × (CLOAD − CSTRAY), Where CSTRAY is Typically

2 pF to 5 pF)

XOA

330Ω

150Ω

0.1µF

XOB

AD9554-1

3.3V

CMOS

TCXO

0.1µF

12214-134

Figure 24. System Clock Input (XOA, XOB) When Using a

TCXO/OCXO with 3.3 V CMOS Output

AD9554-1 Data Sheet

Rev. C | Page 24 of 99

GETTING STARTED

CHIP POWER MONITOR AND STARTUP

The AD9554-1 monitors the voltage on the power supplies at

power-up. The VDD pins provide power to the internal voltage

regulators to provide a 1.2 V supply to the chip. When the internal

1.2 V supply is greater than 0.96 V ± 0.1 V, the device generates

a 25 ms reset pulse. The power-up reset pulse is internal and

independent of the RESET pin. This internal power-up reset

sequence eliminates the need for the user to provide external

power supply sequencing. The M0 through M3 and M5 through

M7 values latch 25 ms after the internal reset pulse. Note that

there is no M4 pin.

During a device reset (either via the power-up reset pulse or the

RESET pin), the M7 to M5 and M3 to M0 multifunction pins

behave as high impedance inputs. At the point where the reset

condition is cleared, level-sensitive latches capture the logic

pattern that is present on the multifunction pins. Wait a

minimum of 25 ms after power on before programming the

device to ensure that the power-on reset (POR) has completed.

MULTIFUNCTION PINS AT RESET/POWER-UP

The AD9554-1 Mx pins have internal 100 kΩ pull-up/pull-

down resistors.

Table 21. Mx Pin Internal Pull-Up/Pull-Down Resistor

Mx Pin Pull-Up/Pull-Down Resistor Startup Function

M0 100 kΩ pull-down resistor I²C address select

M1 None None

M2 None None

M3 100 kΩ pull-down resistor None

M4 Pin does not exist None

M5 100 kΩ pull-down resistor SPI/I²C select

M6 100 kΩ pull-up resistor I²C address select

M7 100 kΩ pull-down resistor I²C address select

Table 22. SPI/IC Serial Port Setup

M7 M6 M5 M0 SPI/I²C Address

Don’t care 0 0 Don’t care Not applicable

Don’t care 1 0 Don’t care Analog Devices, Inc.,

unified SPI (default)

0 0 1 0 I²C, 1101000 (0x68)

0 1 1 0 I²C, 1101001 (0x69)1

1 0 1 0 I²C, 1101010 (0x6A)

1 1 1 0 I²C, 1101011 (0x6B)

0 0 1 1 I²C, 1101100 (0x6C)

0 1 1 1 I²C, 1101101 (0x6D)

1 0 1 1 I²C, 1101110 (0x6E)

1 1 1 1 I²C, 1101111 (0x6F)

1 If M5 is high, the I²C power-on default is via internal pull-up/pull-down

resistors. By pulling M5 high, the user selects I²C mode; the default I²C

address is 0x69.

DEVICE REGISTER PROGRAMMING USING A

The evaluation software contains a programming wizard and a

convenient graphical user interface (GUI) that assists the user

in determining the optimal configuration for the DPLLs,

APLLs, and SYSCLK based on the desired input and output

frequencies. It generates a register setup file with a .STP

extension that is easily readable using a text editor.

The user can configure PLL_0 through PLL_3 independently.

To do so, program the common registers (such as the system

clock and reference inputs) first. Next, the registers that are

unique to PLL_0, PLL_1, PLL_2, or PLL_3 can be configured

independently.

After using the evaluation software to create the setup file, use

the sequence shown in Figure 25 through Figure 28 to program

the AD9554-1.

Data Sheet AD9554-1

Rev. C | Page 25 of 99

WRITE:

ISSUE A

CHIP LEVEL RESET

(PIN OR SOFT RESET)

RST_COUNT =

RST_COUNT + 1

APPLY VDD

(ALL DOMAINS)

START

VDD SETTLED?

REFERENCE INPUT(S)

CAN BE APPLIED ANY

TIME HEREAFTER.

SUBPROCESS:

SYSTEM CLOCK

INITIALIZATION

POR: WAIT 25ms

RST_COUNT > 0

RAISE FLAG FOR

DEBUGGING.

READ:

END

RST_COUNT = 0

YES

CHIP LEVEL

RESET LOOP

USER POWER

SUPPLIES

INITIALIZATION

AND POWER-ON

RESET WAIT

SUBPROCESS:

ANALOG PLL_x

INITIALIZATION

i = 0

i = i + 1

APLL_x ENABLED

i > 3

YES

SOFT WARE

GENERATED

AD9554 SETUP

FILE*

WRITE REGISTER

CONTENT FROM

SETUP FILE

*THE USER MUST ENSURE THAT THE AD9554-1 SETUP FILE INCLUDES WRITES TO REGISTER 0x0FFF, REGISTER 0x1488, REGISTER 0x1588,

12214-100

Figure 25. Main Process—Initialization

AD9554-1 Data Sheet

Rev. C | Page 26 of 99

WRITE:

CAL_COUNT = 0

CAL_COUNT =

CAL_COUNT + 1

WRITE:

START TIMEOUT CLOCK:

TIME = 0

VCO

CALIBRATION

OPERATION

SYSTEM CLOCK

RECALIBRATION LOOP

SYSTEM CLOCK

LOCKED AND

STABLE POLLING

LOOP

0xD01[1:0] = 0x3

CAL_COUNT > 1

TIMEOUT CLOCK:

TIME > SYSCLK_TO*

YES

START

END

(TO RST_COUNT CHECK)

SYSCLK_TO IS A CALCULATED TIMEOUT VALUE. IT IS 100ms AND SYSTEM CLOCK VALIDATION

TIME (REGISTER 0x206 TO REGISTER 0x208: DEFAULT = 50ms)

12214-101

Figure 26. Subprocess—System Clock Initialization

Data Sheet AD9554-1

Rev. C | Page 27 of 99

WRITE:

CAL REG BIT 1 = 0

WRITE:

CAL_COUNT = 0

CAL_COUNT =

CAL_COUNT + 1

WRITE:

CAL REG BIT 1 = 1

WRITE:

START TIMEOUT CLOCK:

TIME = 0

ENSURE THAT CAL REG BIT 1 = 0

FOR ALL CALIBRATION REGISTERS

(0xA00, 0xA20, 0xA40, 0xA60, 0xA80)

WRITE:

SYNC REG BIT 2 = 1

WRITE:

SYNC REG BIT 2 = 0

WRITE:

VCO

CALIBRATION

OPERATION

APLL RECALIBRATION LOOP1

APLL LOCK

DETECT POLLING

LOOP

LOCK REG BIT 3 = 1

CAL_COUNT > 1

TIMEOUT CLOCK:

TIME > 200ms

YES

START

END

(TO RST_COUNT CHECK)

DISTRIBUTION

SYNCHRONIZATION

OPERATION

APLL

ALL

1NOTE THAT THE CALIBRATE ALL AND SOFT SYNC ALL BITS IN REGISTER 0x0A00 CAN BE USED IF THE USER

WANTS TO CALIBRATE OR SYNC ALL FOUR PLLs SIMULTANEOUSLY INSTEAD OF ONE AT A TIME.

HOWEVER, THE USER MUST STILL VERIFY THAT ALL FOUR APLLs ARE LOCKED BY READING THE

INDIVIDUAL APLL LOCK REGISTERS.

2REGISTER 0x0D00 CAN ONLY BE USED TO VERIFY THE LOCK STATE OF EACH APLL

IF THE CORRESPONDING DPLL IS ALSO LOCKED.

CAL REG

0xA00

0xA20

0xA40

0xA60

0xA80

LOCK REG

0xD002

0xD20

0xD40

0xD60

0xD80

SYNC REG

0xA00

0xA20

0xA40

0xA60

0xA80

12214-102

Figure 27. Subprocess—Analog PLL Initialization

AD9554-1 Data Sheet

Rev. C | Page 28 of 99

OUTPUT CLOCK

DISTRIBUTION

SYNCHRONIZATION

FOR PLL_x

SOFTWARE GENERATED

AD9554-1 RELATED

REGISTERS FOR DIFFERENT

DPLL CONFIGURATIONS

WRITE:

SYNC REG BIT 2 = 1

WRITE:

WRITE NEW

BUSINESS CASE

RELATED REGISTERS

WRITE:

START

END

CHANNEL

SYNC REG

0xA20

0xA40

0xA60

0xA80

DISTRIBUTION

SYNCHRONIZATION:

DISABLE OUTxA/OUTxB

TOGGLING

SUBPROCESS:

ANALOG PLL_x

INITIALIZATION

12214-103

Figure 28. Main Process—PLL Reconfiguration

This section provides a programming overview of the register

blocks in the AD9554-1, describing each function and why they

are important. This is supplemental information only needed

when loading the registers without using the .STP file.

The AD9554-1 evaluation software contains a wizard that

determines the register settings based on the input and output

frequencies of the user. It is strongly recommended that the

evaluation software be used to determine these settings.

Multifunction Pins (Optional)

To use any of the multifunction pins for status or control, this

step is required. The multifunction pin parameters are located

at Register 0x0100 to Register 0x010A.

Table 123 has a list of the Mx pin output functions, and Table 124

has a list of Mx pin input functions.

IRQ Functions (Optional)

To use the IRQ feature, this step is required. The IRQ functions

are divided into five groups: common, PLL_0, PLL_1, PLL_2,

and PLL_3.

First, choose the events that trigger an IRQ and then set them in

assigned to the IRQ function. The user can choose to dedicate

one Mx pin to each of the five IRQ groups, or one Mx pin can

be assigned for all IRQs.

The IRQ monitor registers are located at Register 0x0D08 to

IRQ monitor bit at Register 0x0D08 to Register 0x0D16 is set

high when the indicated event occurs.

Individual IRQ events are cleared by using the IRQ clearing

registers at Register 0x0A05 to Register 0x0A14 or by setting the

clear all IRQs bit (Register 0x0A05[0]) to 1b.

The default values of the IRQ mask registers are such that

interrupts are not generated. The default IRQ pin (and Mx pins)

mode is active high CMOS. The user can also select active low

CMOS, open-drain PMOS, and open-drain NMOS independently

on any of these pins.

Watchdog Timer (Optional)

To use the watchdog timer, this step is required. The watchdog

timer control is located at Register 0x010D and Register 0x010E.

The watchdog timer is disabled by default.

The watchdog timer is useful for generating an IRQ at a fixed

interval. The timer is reset by setting the clear watchdog timer

bit in Register 0x0A05[7] to 1.

The user can also program an Mx pin for the watchdog timer

output. In this mode, the Mx pin generates a 40 ns pulse every

time the watchdog timer expires.

System Clock Configuration

The system clock multiplier (SYSCLK) parameters are at

use the following steps:

1. Set the system clock PLL input type and divider values.

2. Set the system clock period. It is essential to program the

system clock period because many of the AD9554-1

subsystems rely on this value.

Data Sheet AD9554-1

Rev. C | Page 29 of 99

3. Set the system clock stability timer. The system clock stability

timer specifies the amount of time that the system clock

PLL must be locked before the device declares that the system

clock is stable. It is critical that the system clock stability

timer be set long enough to ensure that the external source is

completely stable when the timer expires. For instance, a

temperature compensated crystal oscillator (TCXO) can

take longer than 50 ms (the default value for the stability

timer) to stabilize after power is applied.

4. Update all registers (Register 0x000F = 0x01).

5. To calibrate the system clock on the next IO_UPDATE,

write Register 0x0A00 = 0x04.

6. Update all registers (Register 0x000F = 0x01).

Important Notes

If Bit 2 in Register 0x0A00 is set independently to initiate a

system clock PLL calibration, leave this bit set to 1 in all

subsequent writes to Register 0x0A00. If this bit is accidentally

cleared, recalibrate the system clock VCO or issue a calibrate all

command by setting Bit 1 in Register 0x0A00 and by issuing an

IO_UPDATE (Register 0x000F = 0x01).

In addition, the system clock PLL must be locked for the digital

PLL blocks to function correctly and to read back the registers

updated on the system clock domain. These registers include

the status registers, as well as the free running tuning word.

APLL calibration and input reference monitoring and validation

require that the system clock be stable. Therefore, first ensure that

the system clock is stable by checking Bit 1 in Register 0x0D01

when debugging the AD9554-1.

Reference Inputs

The reference input parameters and reference dividers are common

to all PLLs; there is only one reference divider (R divider) for

each reference input. The register address for each reference

input follows:

 Register 0x0300 to Register 0x031E for REFA

 Register 0x0320 to Register 0x033E for REFB

 Register 0x0340 to Register 0x035E for REFC

 Register 0x0360 to Register 0x037E for REFD

These registers include the following settings:

 Reference logic type (such as differential, single-ended)

 Reference divider (20-bit R divider value)

 Reference input period and tolerance

 Reference validation timer

 Phase and frequency lock detector settings

 Phase step threshold

Other reference input settings are in the following registers:

 Reference input enable information is found in the DPLL

Feedback Dividers section.

 Reference power-down information is found in

 Reference switching mode settings are found in

Digital PLL (DPLL) Controls and Settings

The DPLL control parameters are separate for DPLL_0 through

DPLL_3. They reside in the following registers:

 Register 0x0400 to Register 0x041E (DPLL_0)

 Register 0x0500 to Register 0x051E (DPLL_1)

 Register 0x0600 to Register 0x061E (DPLL_2)

 Register 0x0700 to Register 0x071E (DPLL_3)

These registers include the following settings:

 30-bit free running frequency

 DPLL pull-in range limits

 DPLL closed-loop phase offset

 Tuning word history control (for holdover operation)

 Phase slew control (for controlling the phase slew rate

during a closed-loop phase adjustment)

 Demapping control

With the exception of the free running tuning word, the default

values of these registers are fine for normal operation. The free

running frequency of the DPLL determines the frequency that

appears at the APLL input when user free run mode is selected.

The correct free running frequency is required for the APLL to

calibrate and lock correctly.

Output PLLs (APLLs) and Output Drivers

The registers that control the APLLs and output drivers reside

in the following registers:

 Register 0x0430 to Register 0x043E (APLL_0)

 Register 0x0530 to Register 0x053E (APLL_1)

 Register 0x0630 to Register 0x063E (APLL_2)

 Register 0x0730 to Register 0x073E (APLL_3)

The following functions are controlled in these registers:

 APLL settings (feedback divider, charge pump current)

 Output synchronization mode

 Output divider values

 Output enable/disable (disabled by default)

 Output logic type

The APLL calibration and synchronization bits reside in the

following registers:

 Register 0x0A20 (APLL_0)

 Register 0x0A40 (APLL_1)

 Register 0x0A60 (APLL_2)

 Register 0x0A80 (APLL_3)

AD9554-1 Data Sheet

Rev. C | Page 30 of 99

DPLL Feedback Dividers

Each DPLL has separate feedback divider settings for each

reference input, which allows the user to have each digital PLL

perform a different frequency translation. However, there is

only one reference divider (R divider) for each reference input.

The feedback divider register settings for DPLL_0 reside in the

following registers. Feedback divider registers for the remaining

three DPLLs mimic the structure of the DPLL_0 registers, but

are offset by 0x0100 registers.

 Register 0x0440 to Register 0x44C (DPLL_0 for REFA)

 Register 0x044D to Register 0x459 (DPLL_0 for REFB)

 Register 0x045A to Register 0x466 (DPLL_0 for REFC)

 Register 0x0467 to Register 0x473 (DPLL_0 for REFD)

 DPLL_1 for REFA to DPLL_1 for REFD: Same as DPLL_0

but register addresses offset by 0x0100

 DPLL_2 for REFA to DPLL_2 for REFD: Same as DPLL_0

but register addresses offset by 0x0200

 DPLL_3 for REFA to DPLL_3 for REFD: Same as DPLL_0

but register addresses offset by 0x0300

These registers include the following settings:

 Reference priority

 Reference input enable (separate for each DPLL)

 DPLL loop bandwidth and loop filter selection

 DPLL feedback divider (integer portion)

 DPLL feedback divider (fractional portion)

 DPLL feedback divider (modulus portion)

Common Operational Controls

The common operational controls reside at Register 0x0A00 to

 Simultaneous calibration and synchronization of all PLLs

 Global power-down

 Reference power-down

 Reference validation override

 IRQ clearing (for all IRQs)

PLL_0 Through PLL_3 Operational Controls

The PLL_0 through PLL_3 operational controls are located at

 APLL calibration and synchronization

 Output driver enable and power-down

 DPLL reference input switching modes

 DPLL open-loop phase stepping control

The user free run bits that enable user free run mode reside in

the following registers:

 Register 0x0A22 = 0x01 (DPLL_0)

 Register 0x0A42 = 0x01 (DPLL_1)

 Register 0x0A62 = 0x01 (DPLL_2)

 Register 0x0A82 = 0x01 (DPLL_3)

APLL VCO Calibration

VCO calibration ensures that the VCO has sufficient operating

margin to function across the full temperature range. The user

can calibrate each of the four VCOs independently of one

another. When calibrating the APLL VCO, it is important to

remember the following conditions:

 The APLL VCO calibration does not occur until the system

clock is stable.

 The APLL VCO must have the correct frequency from the

30-bit digitally controlled oscillator (DCO) during

calibration. The free running tuning word is found in

 The APLL VCO must be recalibrated any time the APLL

frequency changes.

 APLL VCO calibration occurs on the low to high transition

of the APLL VCO calibration bit (Register 0x0A20[1] for

APLL_0, Register 0x0A40[1] for APLL_1, Register 0x0A60[1]

for APLL_2, and Register 0x0A80[1] for APLL_3).

 The VCO calibration bit is not an autoclearing bit.

Therefore, this bit must be cleared (and an IO_UPDATE

issued) before the APLL is recalibrated.

 The best way to monitor successful APLL calibration is by

monitoring the APLL locked bit in the following registers:

APLL_1, Register 0x0D60[3] for APLL_2, and

Generate the Output Clock

If Register 0x0435 (for PLL_0), Register 0x0535 (for PLL_1),

programmed for automatic clock distribution synchronization

via the DPLL phase or frequency lock, the synthesized output

signal appears at the clock distribution outputs. Otherwise, set and

then clear the soft sync bit (Bit 2 in Register 0x0A20 for APLL_0,

Bit 2 in Register 0x0A40 for APLL_1, Bit 2 in Register 0x0A60

for APLL_2, and Bit 2 in Register 0x0A80 for APLL_3) or use a

multifunction pin input (if programmed accordingly) to generate a

clock distribution sync pulse. This sync pulse causes the

synthesized output signal to appear at the clock distribution

outputs. Note that the sync pulse is delayed until the APLL

achieves lock following APLL calibration.

Generate the Reference Acquisition

After the registers are programmed, the DPLLs lock to the

reference input that has been manually selected (if any), or the

first available reference that has the highest priority.

Data Sheet AD9554-1

Rev. C | Page 31 of 99

THEORY OF OPERATION

XOA

XOB

REFA

REFA A

REFB

REFB B

REFC

REFC C

REFD

REFD D

÷2, ÷4, ÷8

×2

÷R

REFERENCE

MONITORS

AND

CROSSPOINT

MUX

SYSCLK

MULTIPLIER

REF

XTAL

SYSTEM

CLOCK

LOOP

FILTER

OUT1B

DPFD

CLAMP NCO_0

FRAC0 ÷ MOD0 ÷N0 ÷M0 ÷P0

(÷3 TO ÷11)

PFD/CP

FREE RUN

TUNING

WORD

VCO_0

2424MHz TO 3132MHz

÷Q0_B OUT0B

OUT0B

RESET

SCLK/SCL

SDIO/SDA

CONTROL

INTERFACE/LOGIC

INPUT REFERENCE

FREQUENCY RANGE:

2kHz TO 1000MHz

PLL0

SAME DETAIL AS PLL0

VCO_1 RANGE = 3232MHz TO 3905MHz

OUT2B

OUT3B

SAME DETAIL AS PLL0

VCO_2 RANGE = 4842MHz TO 5650MHz

SAME DETAIL AS PLL0

VCO_3 RANGE = 4040MHz TO 4748MHz

PLL1

PLL2

PLL3

OUTPUT FREQUENCY RANGE: 430kHz TO 941MHz

12214-035

Figure 29. Detailed Block Diagram

OVERVIEW

The AD9554-1 provides clocking outputs that are directly

related in phase and frequency to the selected (active) reference

but with jitter characteristics governed by the system clock, the

DCO, and the analog output PLL (APLL). The AD9554-1 can

be thought of as four copies of the AD9557 inside one package,

with a 4:4 crosspoint controlling the reference inputs. The

AD9554-1 supports up to four reference inputs and input

frequencies ranging from 2 kHz to 1000 MHz. The cores of this

device are four digital phase-locked loops (DPLLs). Each DPLL

has a programmable digital loop filter that greatly reduces jitter

transferred from the active reference to the output, and these

four DPLLs operate completely independently of each other.

The AD9554-1 supports both manual and automatic holdover.

While in holdover, the AD9554-1 continues to provide an

output as long as the system clock is present. The holdover

output frequency is a time average of the output frequency

history prior to the transition to the holdover condition. The

device offers manual and automatic reference switchover

capability if the active reference is degraded or fails completely.

The AD9554-1 also has adaptive clocking capability that allows

the user to dynamically change the DPLL divide ratios while the

DPLLs are locked.

The AD9554-1 includes a system clock multiplier, four DPLLs,

and four APLLs. The input signal goes first to the DPLL, which

performs the jitter cleaning and most of the frequency translation.

Each DPLL features a 30-bit DCO output that generates a signal

in the range of 283 MHz to 345 MHz.

The DCO output goes to the APLL, which multiplies the signal

up to a range of 2.4 GHz to 5.6 GHz. This signal is then sent to the

clock distribution section, which consists of a P divider cascaded

with 10-bit channel dividers (divide by 1 to divide by 1024).

The XOA and XOB inputs provide the input for the system clock.

These pins accept a reference clock in the 10 MHz to 268 MHz

range or a 10 MHz to 50 MHz crystal connected directly across

the XOA and XOB inputs. The system clock provides the clocks to

the frequency monitors, the DPLLs, and internal switching logic.

Each APLL on the AD9554-1 has one differential output driver.

Each of the four output drivers has a dedicated 10-bit

programmable post divider. Each differential driver operates up

to 1.25 GHz and is an HCSL driver with a 58 Ω internal

termination resistor on each leg. There are three drive strengths:

 The 14 mA mode is used for HCSL and ac-coupled LVDS.

When used as an LVDS-compatible driver, it must be ac-

coupled and terminated with a 100 Ω resistor across the

differential pair.

 The 28 mA mode produces a voltage swing and is compatible

with LVPECL. If LVPECL signal levels are required, the

designer must ac-couple the AD9554-1 output.

 The 21 mA mode is halfway in between the two other

settings.

The AD9554-1 also includes a demapping control function that

allows the user to adjust each of the AD9554-1 output frequencies

dynamically by periodically writing the actual level and desired

level of a first in, first out (FIFO). These levels are intended to

match the actual levels on the user’s system.

AD9554-1 Data Sheet

Rev. C | Page 32 of 99

REFERENCE INPUT PHYSICAL CONNECTIONS

Four pairs of pins (REFA, REFA to REFD, REFD) provide

access to the reference clock receivers. To accommodate input

signals with slow rising and falling edges, both the differential

and single-ended input receivers employ hysteresis. Hysteresis

also ensures that a disconnected or floating input does not

cause the receiver to oscillate.

When configured for differential operation, the input receivers

accommodate either ac- or dc-coupled input signals. If the

input receiver is configured for dc-coupled LVDS mode, the

input receivers are capable of accepting dc-coupled LVDS

signals; however, only up to a maximum of 10.24 MHz. For

frequencies greater than that, ac-couple the input clock and use

ac-coupled differential mode. The receiver is internally dc

biased to handle ac-coupled operation; however, there is no

internal 50 Ω or 100 Ω termination.

When configured for single-ended operation, the input

receivers exhibit a pull-down load of 47 kΩ (typical). See

reference inputs.

REFERENCE MONITORS

The accuracy of the input reference monitors depends on a

known and accurate system clock period. Therefore, the

function of the reference monitors is not operable until the

system clock is stable.

Reference Period Monitor

Each reference input has a dedicated monitor that repeatedly

measures the reference period. The AD9554-1 uses the

reference period measurements to determine the validity of the

reference based on a set of user provided parameters in the

reference input area of the register map. See Register 0x0304

through Register 0x030E for the settings for Reference A,

Reference B, Register 0x0344 through Register 0x034E for the

settings for Reference C, and Register 0x0364 through

The monitor compares the measured period of a particular

reference input with the parameters stored in the profile register

assigned to that same reference input. The parameters include

the reference period, an inner tolerance, and an outer tolerance.

A 40-bit number defines the reference period in units of

femtoseconds (fs). A 20-bit number defines the inner and outer

tolerances. The value stored in the register is the reciprocal of

the tolerance specification. For example, a tolerance specification

of 50 ppm yields a register value of 1/(50 ppm) = 1/0.000050 =

20,000 (0x04E20).

The use of two tolerance values provides hysteresis for the

monitor decision logic. The inner tolerance applies to a

previously faulted reference and specifies the largest period

tolerance that a previously faulted reference can exhibit before it

qualifies as unfaulted.

The outer tolerance applies to an already unfaulted reference. It

specifies the largest period tolerance that an unfaulted reference

can exhibit before being faulted.

To produce decision hysteresis, the inner tolerance must be less

than the outer tolerance. That is, a faulted reference must meet

tighter requirements to become unfaulted than an unfaulted

reference must meet to become faulted.

Reference Validation Timer

Each reference input has a dedicated validation timer. The

validation timer establishes the amount of time that a previously

faulted reference must remain unfaulted before the AD9554-1

declares that it is valid. The timeout period of the validation

timer is programmable via a 16-bit register (Address 0x030F

and Address 0x0310 for Reference A). The 16-bit number stored in

the validation register represents units of milliseconds (ms),

which yields a maximum timeout period of 65,535 ms.

It is possible to disable the validation timer by programming the

validation timer to 0. With the validation timer disabled, the

user must validate a reference manually via the manual reference

validation override controls register (Register 0x0A02).

Reference Validation Override Control

The user can also override the reference validation logic and

either force an invalid reference to be treated as valid or force a

valid reference to be treated as an invalid reference. These

controls are in Register 0x0A02 to Register 0x0A03.

REFERENCE INPUT BLOCK

Unlike the AD9557, the AD9554-1 separates the DPLL

reference dividers from the feedback dividers.

The reference input block includes the input receiver, the reference

divider (R divider), and the reference input frequency monitor

for each reference input. The reference input settings for REFA

are grouped together in Register 0x0300 to Register 0x031E.

The corresponding registers for REFB through REFD are the

following: Register 0x0320 to Register 0x033E, Register 0x0340 to

respectively.

These registers include the following settings:

 Reference logic type (such as differential, single-ended)

 Reference divider (20-bit R divider value)

 Reference input period and tolerance

 Reference validation timer

 Phase and frequency lock detector settings

 Phase step threshold

Data Sheet AD9554-1

Rev. C | Page 33 of 99

The reference prescaler reduces the frequency of this signal by

an integer factor, R + 1, where R is the 20-bit value stored in the

appropriate profile register and 0 ≤ R ≤ 1,048,575. Therefore,

the frequency at the output of the R divider (or the input to the

time-to-digital converter [TDC]) is as follows:

1

R

TDC

After the R divider, the signal passes to a 4:4 crosspoint that

allows any reference input signal to go to any DPLL.

Each DPLL on the AD9554-1 has an independent set of

feedback dividers for each reference input. A description of

these settings can be found in the Digital PLL (DPLL) Core

section.

The AD9554-1 evaluation software includes a frequency

planning wizard that configures the profile parameters based on

the input and output frequencies.

REFERENCE SWITCHOVER

An attractive feature of the AD9554-1 is its versatile reference

switchover capability. The flexibility of the reference switchover

functionality resides in a sophisticated prioritization algorithm

that is coupled with register-based controls. This scheme

provides the user with maximum control over the state machine

that handles the reference switchover.

The main reference switchover control resides in the user mode

registers in the PLL_0 through PLL_3 operational controls

registers. The reference switching mode bits for each DPLL

include the following:

 Register 0x0A22[4:2] for DPLL_0

 Register 0x0A42[4:2] for DPLL_1

 Register 0x0A62[4:2] for DPLL_2

 Register 0x0A82[4:2] for DPLL_3

These bits allow the user to select one of the five operating

modes of the reference switchover state machine that follows:

 Automatic revertive mode

 Automatic nonrevertive mode

 Manual with automatic fallback mode

 Manual with holdover fallback mode

 Full manual mode without holdover fallback

In automatic modes, a fully automatic priority-based algorithm

selects the active reference. When programmed for automatic

mode, the device chooses the highest priority valid reference.

When two or more references have the same priority, REFA has

preference over REFB, and so on in alphabetical order. However,

the reference position is used as a tiebreaker only and does not

initiate a reference switch.

An overview of the five operating modes follows:

 Automatic revertive mode. The device selects the highest

priority valid reference and switches to a higher priority

reference if it becomes available, even if the reference in

use is still valid. In this mode, the user reference is ignored.

 Automatic nonrevertive mode. The device stays with the

currently selected reference as long as it is valid, even if

a higher priority reference becomes available. The user

reference is ignored in this mode.

 Manual with automatic fallback mode. The device uses the

user reference for as long as it is valid. If it becomes invalid,

the reference input with the highest priority is chosen in

accordance with the priority-based algorithm.

 Manual with holdover fallback mode. The user reference is

the active reference until it becomes invalid. At that point,

the device goes into holdover.

 Full manual mode without holdover fallback. The user

reference is the active reference, regardless of whether it

is valid.

The user also can force the device directly into holdover or free

run operation via the user holdover and user free run bits. In

free run mode, the free run frequency tuning word registers

define the free run output frequency. In holdover mode, the

output frequency depends on the holdover control settings (see

the Holdover section).

Phase Build-Out Reference Switching

The AD9554-1 supports phase build-out reference switching,

which refers to a reference switchover that completely masks

any phase difference between the previous reference and the

new reference. That is, there is virtually no phase change

detectable at the output when a phase build-out switchover

occurs.

DIGITAL PLL (DPLL) CORE

DPLL Overview

The AD9554-1 contains four separate DPLL cores (one each for

DPLL_0 through DPLL_3), and each core operates independently

of one another. A diagram of a single core is shown in Figure 30.

Many of the blocks shown in this diagram are purely digital.

DIGITAL

LOOP

FILTER

÷N0

24-BIT/24-BIT

RESOLUTION

FRAC0/

MOD0

18-BIT

INTEGER

TUNING

WORD

CLAMP

AND

HISTORY

FREE RUN

30-BIT NCO

DPFD

SYSTEM

CLOCK

FROM APLL_0

TO APLL_0

R DIVIDER

(20-BIT)

REF

INPUT

MUX

REF

INPUT

12214-137

Figure 30. DPLL_0 Core

AD9554-1 Data Sheet

Rev. C | Page 34 of 99

The start of the DPLL signal chain is the reference signal, fR,

which has been divided by the R divider and then routed

through the crosspoint switch to the DPLL. The frequency of

this signal (fTDC) is

fTDC = fR/1R

This is the frequency used by the TDC inside the DPLL.

A TDC samples the output of the R divider. The TDC/phase

frequency detector (PFD) produces a time series of digital

words and delivers them to the digital loop filter. The digital

loop filter offers the following:

 The determination of the filter response by numeric

coefficients rather than by discrete component values

 The absence of analog components (R/L/C) that eliminate

tolerance variations due to aging

 The absence of thermal noise associated with analog

components

 The absence of control node leakage current associated with

analog components (a source of reference feedthrough

spurs in the output spectrum of a traditional APLL)

The digital loop filter produces a time series of digital words at

its output and delivers them to the frequency tuning input of a

Σ- modulator. The digital words from the loop filter steer the

Σ- modulator frequency toward frequency and phase lock

with the input signal (fTDC).

Each DPLL includes a feedback divider that causes the digital

loop to operate at an integer-plus-fractional multiple. The

output of the DPLL is











 MOD

FRAC

Nff TDCOUT_DPLL 1)(

where:

N is the 18-bit value stored in the appropriate profile registers

(Register 0x0444 to Register 0x0446 for DPLL_0 REFA).

FRAC and MOD are the 24-bit numerators and denominators of

the fractional feedback divider block. The fractional portion of the

feedback divider can be bypassed by setting FRAC or MOD to 0.

Note that there are four DPLLs. In the Register Map section and

the Register Map Bit Descriptions section, N0, FRAC0, and

MOD0 are used for DPLL_0, and N1, FRAC1, MOD1 are used

for DPLL_1, and so on.

For optimal performance, the DPLL output frequency is typically

300 MHz to 350 MHz. Note that the DPLL output frequency is

the same as APLL input frequency.

TDC/PFD

The PFD is an all-digital block. It compares the digital output

from the TDC (which relates to the active reference edge) with

the digital word from the feedback block. It uses a digital code

pump (rather than a conventional charge pump) to generate the

error signal that steers the Σ- modulator frequency toward

phase lock.

Programmable Digital Loop Filter

The AD9554-1 loop filter is a third-order digital IIR filter that is

analogous to the third-order analog filter shown in Figure 31.

C1 R2

12214-015

Figure 31. Third-Order Analog Loop Filter

The AD9554-1 has a default loop filter coefficient for two DPLL

settings: nominal (70°) phase margin and high (88.5°) phase

margin. The high phase margin setting is for applications that

require <0.1 dB of closed-loop peaking. While these settings do

not normally need to be changed, the user can contact Analog

Devices for assistance with calculating new coefficients to tailor

the loop filter to specific requirements.

The AD9554-1 loop filter block features a simplified

architecture in which the user enters the desired loop

characteristics (such as loop bandwidth) directly into the DPLL

registers. This architecture makes the calculation of individual

coefficients unnecessary in most cases, while still offering

extensive flexibility.

DPLL Digitally Controlled Oscillator (DCO) Free Run

Frequency

The AD9554-1 uses a Σ- modulator as a DCO. The DCO free

run frequency can be calculated by

FTW0

DCOint

SYSNDCO_FREERU





where:

fSYS is the system clock frequency. See the System Clock

(SYSCLK) section for information on calculating the system

clock frequency.

DCOint is the DCO integer setting. The DCO integer is usually 7,

and it can be found in Register 0x0404[3:0] for DPLL_0.

FTW0 is the value in Register 0x0400 to Register 0x0403 for

DPLL_0 (see Table 31 for corresponding values for DPLL_1

through DPLL_3).

Adaptive Clocking

The AD9554-1 supports adaptive clocking applications such as

asynchronous mapping and demapping. For these applications,

the output frequency can be dynamically adjusted by up to

±100 ppm from the nominal output frequency without manually

breaking the DPLL loop and reprogramming the device.

The following registers are used in this function:

 Register 0x0444 to Register 0x0446 (DPLL_0 N0 divider)

 Register 0x0447 to Register 0x0449 (DPLL_0 FRAC0 divider)

 Register 0x044A to Register 0x044C (DPLL_0 MOD0 divider)

Data Sheet AD9554-1

Rev. C | Page 35 of 99

Note that the register values shown are for REFA/DPLL_0.

There are corresponding registers for all reference input and

DPLL combinations.

Writing to these registers requires an IO_UPDATE by writing

0x01 to Register 0x000F before the new values take effect.

To make small adjustments to the output frequency, vary the

FRAC (FRAC0 through FRAC3) and issue an IO_UPDATE.

The advantage to using only FRAC to adjust the output

frequency is that the DPLL does not briefly enter holdover.

Therefore, the FRAC bit can be updated as quickly as the phase

detector frequency of the DPLL.

Writing to the N (N0 through N3) and MOD (M0 through M3)

dividers allows larger changes to the output frequency. When

the AD9554-1 detects a write in the N or MOD value, it

automatically enters and exits holdover for a brief instant

without any disturbance in the output frequency. This limits

how quickly the output frequency can be adapted.

It is important to note that the amount of frequency adjustment

is limited to ±100 ppm before the output PLL (APLL) needs a

recalibration. Variations larger than ±100 ppm are possible, but

such variations can compromise the ability of the AD9554-1 to

maintain lock over temperature extremes.

It is also important to remember that the rate of change in

output frequency depends on the DPLL loop bandwidth.

DPLL Phase Lock Detector

The DPLL contains an all-digital phase lock detector. The user

controls the threshold sensitivity and hysteresis of the phase

detector via the profile registers.

The lock detector behaves in a manner analogous to water in a

tub (see Figure 32). The total capacity of the tub is 4096 units,

with −2048 denoting empty, 0 denoting the 50% point, and

+2048 denoting full. The tub also has a safeguard to prevent

overflow. Furthermore, the tub has a low water mark at −1024

and a high water mark at +1024. To change the water level, the

user adds water with a fill bucket or removes water with a drain

bucket. The user specifies the size of the fill and drain buckets

via the 8-bit fill rate and drain rate values in the profile registers.

The water level in the tub is what the lock detector uses to

determine the lock and unlock conditions. When the water level

is below the low water mark (−1024), the lock detector indicates

an unlock condition. Conversely, when the water level is above

the high water mark (+1024), the lock detector indicates a lock

condition. When the water level is between the marks, the lock

detector holds its last condition. This concept appears graphically

in Figure 32, with an overlay of an example of the instantaneous

water level (vertical) vs. time (horizontal) and the resulting

lock/unlock states.

2048

–2048

1024

–1024

LOCK LEVEL

UNLOCK LEVEL

LOCKED UNLOCKED

STATE

FILL

RATE DRAIN

RATE

12214-017

Figure 32. Lock Detector Diagram

During any given PFD phase error sample, the lock detector

either adds water with the fill bucket or removes water with the

drain bucket (one or the other but not both). The decision of

whether to add or remove water depends on the threshold level

specified by the user. The phase lock threshold value is a 24-bit

number stored in the profile registers and is expressed in

picoseconds. Thus, the phase lock threshold extends from 10 ns

to ±16.7 µs and represents the magnitude of the phase error at

the output of the PFD.

The phase lock detector compares each phase error sample at

the output of the PFD to the programmed phase threshold value. If

the absolute value of the phase error sample is less than or equal

to the programmed phase threshold value, the detector control

logic dumps one fill bucket into the tub. Otherwise, it removes

one drain bucket from the tub. Note that it is the magnitude,

relative to the phase threshold value, that determines whether to fill

or drain the bucket, and not the polarity of the phase error sample.

If more filling is taking place than draining, the water level in

the tub eventually rises above the high water mark (+1024),

which causes the lock detector to indicate lock. If more draining

is taking place than filling, the water level in the tub eventually

falls below the low water mark (−1024), which causes the lock

detector to indicate unlock. The ability to specify the threshold

level, fill rate, and drain rate enables the user to tailor the operation

of the lock detector to the statistics of the timing jitter

associated with the input reference signal.

Note that whenever the AD9554-1 enters the free run or

holdover mode, the DPLL phase lock detector indicates an

unlocked state. However, when the AD9554-1 performs a

reference switch, phase step detection, or loop bandwidth

change, the state of the lock detector prior to the switch is

preserved during the transition period.

DPLL Frequency Lock Detector

The operation of the frequency lock detector is identical to that

of the phase lock detector. The only difference is that the fill or

drain decision is based on the period deviation between the

reference and feedback signals of the DPLL instead of the phase

error at the output of the PFD.

AD9554-1 Data Sheet

Rev. C | Page 36 of 99

The frequency lock detector uses a 24-bit frequency threshold

threshold value extends from 10 ps to ±16.7 µs. It represents the

magnitude of the difference in period between the reference

and feedback signals at the input to the DPLL. For example, if

the divided down reference signal is 80 kHz and the feedback

signal is 79.32 kHz, the period difference is approximately

107.16 ns (|1/80,000 − 1/79,320| ≈ 107.16 ns).

Frequency Clamp

The AD9554-1 digital PLL features a digital tuning word clamp

that ensures that the digital PLL output frequency stays within a

defined range. This feature is very useful to eliminate undesirable

behavior in cases where the reference input clocks can be

unpredictable. The tuning word clamp is also useful to guarantee

that the APLL never loses lock by ensuring that the APLL VCO

frequency stays within its tuning range.

Frequency Tuning Word History

The AD9554-1 has the ability to track the history of the tuning

word samples generated by the DPLL digital loop filter output.

It does so by periodically computing the average tuning word

value over a user-specified interval. This average tuning word is

used during holdover mode to maintain the average frequency

when no input references are present.

LOOP CONTROL STATE MACHINE

Switchover

Switchover occurs when the loop controller switches directly

from one input reference to another. The AD9554-1 handles a

reference switchover by briefly entering holdover mode, loading

the new DPLL parameters, and then immediately recovering.

During the switchover event, however, the AD9554-1 preserves

the status of the lock detectors to avoid phantom unlock

indications.

Holdover

The holdover state of the DPLL is typically used when none of

the input references are present; although, the user can also

manually engage holdover mode. In holdover mode, the output

frequency remains constant. The accuracy of the AD9554-1 in

holdover mode is dependent on the device programming and

availability of the tuning word history.

Recovery from Holdover

When in holdover and a valid reference becomes available, the

device exits holdover operation. The loop state machine restores

the DPLL to closed-loop operation, locks to the selected

reference, and sequences the recovery of all the loop parameters

based on the profile settings for the active reference.

Note that, if the DPLL_x user holdover bit is set, the device does

not automatically exit holdover when a valid reference is available.

However, automatic recovery can occur after clearing the user

holdover bit.

Data Sheet AD9554-1

Rev. C | Page 37 of 99

SYSTEM CLOCK (SYSCLK)

SYSCLK INPUTS

Functional Description

The SYSCLK circuit provides a low jitter, stable, high frequency

clock for use by the rest of the chip. The XOA and XOB pins

connect to the internal SYSCLK multiplier. The SYSCLK

multiplier can synthesize the system clock by connecting a

crystal resonator across the XOA and XOB input pins or by

connecting a low frequency clock source. The optimal signal for

the system clock input is either a crystal in the 50 MHz range or

an ac-coupled square wave with 800 mV p-p amplitude.

SYSCLK Reference Frequency

For the AD9554-1 to function properly, enter the system clock

reference frequency into Register 0x0202 to Register 0x0205.

The ability of the AD9554-1 to accurately measure the frequency of

the reference input depends on how accurately this register

setting matches the frequency on the system clock input.

Choosing the SYSCLK Source

There are two internal paths for the SYSCLK input signal:

crystal resonator (XTAL) and nonXTAL.

Using a TCXO for the system clock is a common use for the

nonXTAL path. Applications requiring DPLL loop bandwidths

of less than 50 Hz or high stability in holdover mode require a

TCXO or oven controlled crystal oscillator (OCXO). As an

alternative to the 49.152 MHz crystal for these applications, the

AD9554-1 reference design uses a 19.2 MHz TCXO, which

offers excellent holdover stability and a good combination of

low jitter and low spurious content.

The differential receiver connected to the XOA and XOB pins is

self-biased to a dc level of ~0.6 V, and ac coupling is strongly

recommended to maintain a 50% input duty cycle. When a 3.3 V

CMOS oscillator is in use, it is important to ac-couple and use a

voltage divider to reduce the input high voltage to a maximum

of 1.14 V. The target voltage swing is 800 mV p-p. See Figure 24

for details on connecting a 3.3 V CMOS TCXO to the system

clock input.

The nonXTAL input path permits the user to provide an

LVPECL, LVDS, CMOS, or sinusoidal low frequency clock for

multiplication by the integrated SYSCLK PLL. However, when

using a sinusoidal input signal, it is best to use a frequency of

≥20 MHz. Otherwise, the resulting low slew rate can lead to

poor noise performance. Note that there is an optional 2×

frequency multiplier to double the rate at the input to the

SYSCLK PLL and potentially reduce the PLL in-band noise.

However, to avoid exceeding the maximum PFD rate of 300 MHz,

the 2× frequency multiplier is only for input frequencies less than

150 MHz. Note that using the doubler when the duty is not

close to 50% results in higher spurious noise and may prevent

the system clock PLL from locking.

The nonXTAL path also includes an input divider (M) that is

programmable for divide-by-1, -2, -4, or -8. The purpose of the

divider is to allow additional flexibility in setting the system

clock frequency to avoid spurs in the output clocks.

The XTAL path enables the connection of a crystal resonator

(typically 12 MHz to 50 MHz) across the XOA and XOB pins.

An internal amplifier provides the negative resistance required

to induce oscillation. The internal amplifier expects an AT cut,

fundamental mode crystal with a 100 Ω maximum motional

resistance. The following crystals, listed in alphabetical order,

may meet these criteria. Analog Devices does not guarantee

their operation with the AD9554-1, nor does Analog Devices

endorse one crystal supplier over another. The AD9554-1

reference design uses a 49.152 MHz crystal, which is high

performance, low spurious content, and readily available.

 AVX/Kyocera CX3225SB

 ECS, Inc. ECX-32

 Epson/Toyocom TSX-3225

 Fox FX3225BS

 NDK NX3225SA

 Siward SX-3225

 Suntsu SCM10B48-49.152 MHz

SYSCLK MULTIPLIER

The SYSCLK PLL multiplier is an integer-N design with an

integrated VCO. It provides a means to convert a low frequency

clock input to the desired system clock frequency, fSYS (2250 MHz

to 2415 MHz). The SYSCLK PLL multiplier accepts input

signals of between 10 MHz and 268 MHz. The PLL contains a

feedback divider (K) that is programmable for divide values

between 4 and 255.

fSYS = fOSC × JDIVSYSCLK

KDIVSYSCLK

where:

fOSC is the frequency at the XOA and XOB pins.

SYSCLK_KDIV is the K divider value stored in Register 0x0200.

SYSCLK_JDIV is the system clock J1 divider that is determined

by setting Register 0x0201[2:1].

If the system clock doubler is used, the value of SYSCLK_KDIV

should be half of its original value.

The system clock multiplier features a simple lock detector that

compares the time difference between the reference and

feedback edges. The most common cause of the SYSCLK

multiplier not locking is a non-50% duty cycle at the SYSCLK

input while the system clock doubler is enabled.

AD9554-1 Data Sheet

Rev. C | Page 38 of 99

System Clock Stability Timer

Because multiple blocks inside the AD9554-1 depend on the

system clock being at a known frequency, the system clock must

be stable before activating the monitors. At initial power-up, the

system clock status is not known; therefore, it is reported as being

unstable. After the system clock registers have been programmed

and the SYSCLK VCO has been calibrated, the system clock

PLL locks shortly thereafter.

When the SYSCLK PLL locks, a timer runs for the duration stored

in the system clock stability period registers. If the locked condition

is violated any time during this waiting period, the timer is reset

and halted until a locked condition is reestablished. After the

specified period elapses, the internal logic of the AD9554-1

reports the system clock as stable.

Note that any time the system clock stability timer is changed in

The system clock stability timer starts counting when the next

IO_UDATE is issued (assuming that the system clock PLL is

locked).

Data Sheet AD9554-1

Rev. C | Page 39 of 99

OUTPUT ANALOG PLL (APLL)

There are four output analog PLLs (APLLs) on the AD9554-1.

They provide the frequency upconversion from the digital PLL

(DPLL) outputs. The frequency ranges for each APLL are in

Table 11.

Each APLL also provides a noise filter on the DPLL output. The

APLL reference input is the output of the DPLL. The feedback

divider is an integer divider. The loop filter is partially integrated

with one external 15 nF capacitor that connects to the internal

LDO. In addition to the capacitor, there is an additional 0.22 µF

capacitor from the LDO pin to ground. The nominal loop

bandwidth for all four APLLs is 240 kHz.

The APLL_0 block diagram is shown in Figure 33. APLL_1

through APLL_3 are copies of APLL_0 with different VCO

ranges. Each APLL_x input is connected to the respective

DPLL_x output, and each APLL_x output is connected to the

respective Px divider.

LF_0 CAP

LF_0 PIN

VCO_0

PFD

FROM DPLL_0 TO P0

DIVIDER

INTEGER DIVIDE

OUTPUT PLL (APLL_0)

÷M0

LDO_0 PIN 17

12214-138

Figure 33. APLL_0 Block Diagram

APLL CONFIGURATION

The frequency wizard that is included in the evaluation software

configures the APLL, and the user should not need to make

changes to the APLL settings. However, there may be special

cases where the user may want to adjust the APLL loop

bandwidth to meet a specific phase noise requirement. The

easiest way to change the APLL loop bandwidth is to adjust the

APLL charge pump current, which is controlled in the following

registers:

 Register 0x0430 (APLL_0)

 Register 0x0530 (APLL_1)

 Register 0x0630 (APLL_2)

 Register 0x0730 (APLL_3)

There is sufficient stability (68° of phase margin) in the APLL

default settings to permit a broad range of adjustment without

causing the APLL to be unstable.

APLL CALIBRATION

Calibration of the APLLs must be performed at startup and

whenever the nominal input frequency to the APLL changes by

more than ±100 ppm; although, the APLL maintains lock over

voltage and temperature extremes without recalibration.

APLL calibration at startup is normally performed during initial

To recalibrate the APLL VCO after the chip has been running,

first, input the new settings (if any). The user can calibrate

APLL_0 without disturbing any of the other three APLLs

(APLL_1, APLL_2, and APLL_3).

Use the following steps to recalibrate the APLL VCO. It is

important to note that an IO_UPDATE (Register 0x000F =

0x01) is needed after each of these steps.

1. Ensure that the DPLL free run tuning word is set

(Register 0x0A22[0] = 1b for DPLL_0,

2. Clear the desired APLL calibration bit

(Register 0x0A20[1] = 0b for APLL_0,

Alternatively, the user can write Register 0xA00 = 0x00 to

clear the calibrate all bit. This allows the user to set this bit

in the next step to calibrate all four VCOs at the same time.

3. Set the desired APLL calibration bit

(Register 0x0A20[1] = 1b for APLL_0,

Alternatively, the user can write Register 0xA00 = 0x02

to calibrate all four VCOs at the same time.

4. To ensure that the APLLs have locked, poll the APLL lock

status (Register 0x0D20[3] = 1b indicates lock for APLL_0,

5. Ensure that the DPLL free run tuning word is cleared

(Register 0x0A22[0] = 0b for DPLL_0,

AD9554-1 Data Sheet

Rev. C | Page 40 of 99

CLOCK DISTRIBUTION

FROM VCO_0

CHIP RESET

SYNC

430kHz TO 941MHz

CHANNEL

SYNC

BLOCK

MAX

1.25GHz

CHANNEL SYNC

OUT0B

DIVIDER

10-BIT INTEGER

÷Q0_B

12214-139

Figure 34. Clock Distribution Block Diagram from VCO_0 for the PLL_0

The AD9554-1 has four identical clock distribution sections for

PLL_0 through PLL_3. See Figure 34 for a diagram of the clock

distribution block for PLL_0.

CLOCK DIVIDERS

P Dividers

The first block in each clock distribution section is the P divider.

The P divider divides the VCO output frequency down to a

frequency of ≤1.25 GHz and has special circuitry to maintain a

50% duty cycle for any divide ratio.

The following registers contain the P divider settings:

 Register 0x0434[3:0] for PLL_0, P0 divider

 Register 0x0534[3:0] for PLL_1, P1 divider

 Register 0x0634[3:0] for PLL_2, P2 divider

 Register 0x0734[3:0] for PLL_3, P3 divider

Channel Dividers

The channel divider blocks, Q0_B through Q3_B are 10-bit

integer dividers with a divide range of 1 to 1024. The channel

divider block contains duty cycle correction that generates

approximately 50% duty cycle for both even and odd divide

ratios. The maximum input frequency to the channel dividers is

1.25 GHz.

The following registers contain the channel dividers:

 Register 0x043C to Register 0x043E for Q0_B divider

 Same as Q0_B but offset by 0x0100 registers for Q1_B

divider

 Same as Q0_B but offset by 0x0200 registers for Q2_B

divider

 Same as Q0_B but offset by 0x0300 registers for Q3_B

divider

OUTPUT AMPLITUDE AND POWER-DOWN

The output drivers can be individually powered down. The

output mode control (including power-down) can be found in

the following registers:

 Register 0x043B[2:1] for OUT0B

 Register 0x053B[2:1] for OUT1B

 Register 0x063B[2:1] for OUT2B

 Register 0x073B[2:1] for OUT3B

The operating mode controls include the following:

 Output drive strength

 Output polarity

 Divide ratio

 Phase of each output channel

The HCSL drivers feature a programmable drive strength that

allows the user to choose between a strong, high performance

driver or a lower power setting with less electromagnetic

interference (EMI) and crosstalk. The best setting is application

dependent.

All outputs have three current settings that provide increased

output amplitude in applications that require it. However, the

only modes that support dc-coupling without termination at the

destination are the 14 mA HCSL and 21 mA modes. The 28 mA

mode must have either 50 Ω to ground on each leg or 100 Ω

across the differential pair.

For applications where LVPECL levels are required, the user

must choose the 28 mA mode, ac-couple the output signal, and

provide 100 Ω termination across the differential pair at the

destination. Damage to the output drivers can result if 28 mA

mode is used without external termination resistors (either to

ground or across the differential pair). See the Input/Output

Termination Recommendations section for recommended

termination schemes.

Data Sheet AD9554-1

Rev. C | Page 41 of 99

CLOCK DISTRIBUTION SYNCHRONIZATION

Divider Synchronization

The dividers in the channels can be synchronized with each

other. At power-up, they are held static until a synchronization

signal is initiated through the serial port or a DPLL locked

synchronization. This mode of operation provides time for

APLL calibration before the outputs are enabled.

A user initiated sync signal can also be supplied to the dividers

at any time (as a manual synchronization) using an Mx pin.

A channel can be programmed to ignore the sync function.

When programmed to ignore the sync function, the channel

sync block issues a sync pulse immediately, and the channel

ignores all other sync signals.

The digital logic triggers a sync event from one of the following

sources:

 Register programming through serial port

 A multifunction pin configured for the sync signal

 Other automatic conditions determined by the DPLL

configuration: DPLL lock or reference clock synchronization

AD9554-1 Data Sheet

Rev. C | Page 42 of 99

STATUS AND CONTROL

MULTIFUNCTION PINS (M0 TO M3 AND M5 TO M7)

The AD9554-1 has seven digital CMOS input/output pins (M0 to

M3 and M5 to M7) that are configurable for a variety of uses.

Note that there is no M4 pin for this device. To use these

functions, the user must set them by writing to Register 0x0100

to Register 0x0101. The function of these pins is programmable

via the register map. Each pin can control or monitor an

assortment of internal functions based on Register 0x0103 to

The Mx pins feature a special write detection logic that prevents

these pins from behaving unpredictably when the Mx pins

function changes. When the user writes to these registers, the

existing Mx pin function stops. The new Mx pin function takes

effect on the next IO_UPDATE (Register 0x000F = 0x01).

The Mx pins operate in one of four modes: active high CMOS,

active low CMOS, open-drain PMOS, and open-drain NMOS.

Table 23. Mx Pins Four Modes of Operation

Setting Mode Description

00 Active

high

CMOS

When deasserted, the Mx pin is Logic 0.

When asserted, the Mx pin is Logic 1,

which is the default operating mode

01 Active low

CMOS

When deasserted, the Mx pin is Logic 1.

When asserted, the Mx pin is Logic 0.

10 Open-

drain

PMOS

When deasserted, the Mx pin is high

impedance.

When the Mx pin is asserted, it is active

high; it requires an external pull-down

resistor.

11 Open-

drain

NMOS

When deasserted, the Mx pin is high

impedance.

When the Mx pin is asserted, it is active

low; it requires an external pull-up

resistor.

To monitor an internal function with a multifunction pin, write

a Logic 1 to the most significant bit of the register associated

with the desired multifunction pin. The value of the seven least

significant bits of the register defines the control function, as

shown in Table 123.

To control an internal function with a multifunction pin, write a

Logic 0 to the most significant bit of the register associated with

the desired multifunction pin. The monitored function depends

on the value of the seven least significant bits of the register, as

shown in Figure 41.

Note that each Mx pin has an open-drain mode that allows the

user to perform logical AND and logical OR functions with the

Mx pin outputs. For instance, it is possible to connect the IRQ

lines of multiple AD9554-1s on one board together and to make

the IRQ line the logical OR of each AD9554-1 IRQ line.

It is also possible to have an input function like IRQ clearing to

be the logical combination of multiple inputs. For example, IRQ

clearing is desired only if M2 is high and M3 is low, and either

M0 is high or M1 is low.

In function form, this is the following:

Result = (M0 || !M1) && M2 && !M3

To accomplish this, set the M0 through M3 pins as the IRQ clearing

function, and set the Mx pin modes of operation as the following:

 M0 = OR true signal (Register 0x100[1:0] = 10)

 M1 = OR inverted signal (Register 0x100[3:2] = 11)

 M2 = AND true signal (Register 0x100[5:4] = 00)

 M3 = AND inverted signal (Register 0x100[7:6] = 01)

IRQ FUNCTION

The AD9554-1 IRQ function can be assigned to any Mx pin.

There are five IRQ categories: PLL0, PLL1, PLL2, PLL3, and

common. This means an Mx pin can be set to respond only to

IRQs that relate to one of the PLLs or to common functions. An

Mx pin can also be set to respond to all IRQs.

The AD9554-1 asserts an IRQ when any bit in the IRQ monitor

bit in this register is associated with an internal function that is

capable of producing an interrupt. Furthermore, each bit of the

IRQ monitor register is the result of a logical AND of the

associated internal interrupt signal and the corresponding bit

in the IRQ mask register (Register 0x010F to Register 0x011D).

That is, the bits in the IRQ mask registers have a one-to-one

correspondence with the bits in the IRQ monitor registers.

When an internal function produces an interrupt signal and the

associated IRQ mask bit is set, the corresponding bit in the IRQ

monitor register is set. Be aware that clearing a bit in the IRQ

mask register removes only the mask associated with the

internal interrupt signal. It does not clear the corresponding bit

in the IRQ monitor register.

The IRQ function is edge triggered which means that if the

condition that generated an IRQ (for example, loss of DPLL_0

lock) still exists after an IRQ is cleared, the IRQ does not reactivate

until DPLL_0 lock is restored and lost again. However, if the

IRQs are enabled when DPLL_0 is not locked, an IRQ is generated.

The IRQ function of an Mx pin is the result of a logical OR of

all the IRQ monitor register bits. The AD9554-1 asserts an IRQ

as long as any of the IRQ monitor register bits is a Logic 1. Note

that it is possible to have multiple bits set in the IRQ monitor

registers. Therefore, when the AD9554-1 asserts an IRQ, it may

indicate an interrupt from several different internal functions. The

IRQ monitor registers provide a way to interrogate the AD9554-1

to determine which internal function(s) produced the interrupt.

Data Sheet AD9554-1

Rev. C | Page 43 of 99

Typically, when the AD9554-1 asserts an IRQ, the user interrogates

the IRQ monitor registers to identify the source of the interrupt

request. After servicing an indicated interrupt, the user must

clear the associated IRQ monitor register bit via the IRQ

clearing registers (Address 0x0A05 to Address 0x0A14). The

bits in the IRQ clearing registers have a one-to-one

correspondence with the bits in the IRQ monitor registers.

Note that the IRQ clearing registers are autoclearing. The Mx

pin associated with an IRQ remains asserted until the user clears all

of the bits in the IRQ monitor registers that indicate an interrupt.

All IRQ monitor register bits can be cleared by setting the clear

all IRQs bit in the IRQ register (Register 0x0A05). Note that the

bits in Register 0x0A05 are autoclearing. Setting Bit 0 results in

the deassertion of all IRQs. Alternatively, the user can program

any of the multifunction pins to clear all IRQs, which allows the

user to clear all IRQs by means of a hardware pin rather than by

a serial input/output port operation.

WATCHDOG TIMER

The watchdog timer is a general-purpose programmable timer.

To set the timeout period, the user writes to the 16-bit watchdog

timer register (Address 0x010D to Address 0x010E). A value of

0x0000 in this register disables the timer. A nonzero value sets

the timeout period in milliseconds, giving the watchdog timer a

range of 1 ms to 65.535 sec. The relative accuracy of the timer is

approximately 0.1% with an uncertainty of 0.5 ms.

If enabled, the timer runs continuously and generates a timeout

event when the timeout period expires. The user has access to

the watchdog timer status via the IRQ mechanism and the

multifunction pins (M0 to M3 and M5 to M7). In the case of the

multifunction pins, the timeout event of the watchdog timer is a

pulse that lasts 96 system clock periods (which is approximately

40 ns).

There are two ways to reset the watchdog timer (thereby

preventing it from causing a timeout event). The first method is

to write a Logic 1 to the autoclearing clear watchdog timer bit in

the clear IRQ groups register (Register 0x0A05, Bit 7). Alternatively,

the user can program any of the multifunction pins to reset the

watchdog timer. When used in this way, the user can reset the

timer by means of a hardware pin rather than by a serial I/O

port operation.

AD9554-1 Data Sheet

Rev. C | Page 44 of 99

SERIAL CONTROL PORT

The AD9554-1 serial control port is a flexible, synchronous serial

communications port that provides a convenient interface to many

industry-standard microcontrollers and microprocessors. The

AD9554-1 serial control port is compatible with most synchronous

transfer formats, including IC, Motorola SPI, and Intel SSR

protocols. The serial control port allows read/write access to

the AD9554-1 register map.

The AD9554-1 uses the Analog Devices unified SPI protocol (see

Analog Devices Serial Control Interface Standard). The unified

SPI protocol guarantees that all new Analog Devices products using

the unified protocol have consistent serial port characteristics.

The SPI port configuration is programmable via Register 0x0000.

This register is a part of the SPI control logic rather than in the

Unified SPI differs from the SPI port found on older products

like the AD9557 and AD9558 in the following ways:

 Unified SPI does not have byte counts. A transfer is

terminated when the CS pin goes high. The W1 and W0

bits in the traditional SPI become the A12 and A13 bits of

the register address. This is similar to streaming mode in

the traditional SPI.

 The address ascension bit (Register 0x0000) controls

whether register addresses are automatically incremented

or decremented regardless of the LSB/MSB first setting. In

traditional SPI, LSB first dictated autoincrements and MSB

first dictated autodecrements of the register address.

 Devices that adhere to the unified serial port have a

consistent structure of the first 16 register addresses.

Although the AD9554-1 supports both the SPI and I2C serial

port protocols, only one is active following power-up (as

determined by the M0, M5, M6, and M7 multifunction pins

during the start-up sequence). The only way to change the serial

port protocol is to reset (or power cycle) the device.

SPI/I²C PORT SELECTION

Because the AD9554-1 supports both SPI and IC protocols, the

active serial port protocol depends on the logic state of M0, M5,

M6, and M7 pins at reset or power-on. See Table 22 for the I2C

address assignments.

SPI SERIAL PORT OPERATION

Pin Descriptions

The SCLK (serial clock) pin serves as the serial shift clock. This

pin is an input. SCLK synchronizes serial control port read and

write operations. The rising edge SCLK registers write data bits,

and the falling edge registers read data bits. The SCLK pin

supports a maximum clock rate of 50 MHz.

Data is transferred on the serial data input/output (SDIO) pin.

The AD9554-1 does not have a dedicated SDO pin, so it

supports only bidirectional (3-wire) SPI mode.

The CS (chip select) pin is an active low control that gates read

and write operations. Assertion (active low) of the CS pin

initiates a write or read operation to the AD9554-1 SPI port.

Any number of data bytes can be transferred in a continuous

stream. The register address is automatically incremented or

decremented based on the setting of the address ascension bit

(Register 0x0000). CS must be deasserted at the end of the last

byte transferred, thereby ending the stream mode. This pin is

internally connected to a 10 kΩ pull-up resistor. When CS is

high, the SDIO pin goes into a high impedance state.

Implementation Specific Details

A detailed description of the unified SPI protocol can be found

in the Analog Devices Serial Control Interface Standard, which

covers items such as timing, command format, and addressing.

The following product specific items are defined in the unified

SPI protocol:

 Analog Devices unified SPI protocol revision: 1.0

 Chip type: 0x5

 Product ID: 0x009

 Physical layer: 3-wire supported and 1.5 V, 1.8 V, and 2.5 V

operation supported

 Optional single-byte instruction mode: not supported

 Data link: not used

 Control: not used

Communication Cycle—Instruction Plus Data

The unified SPI protocol consists of a two-part communication

cycle. The first part is a 16-bit instruction word that is

coincident with the first 16 SCLK rising edges and a payload.

The instruction word provides the AD9554-1 serial control port

with information regarding the payload. The instruction word

includes the R/W bit that indicates the direction of the payload

transfer (that is, a read or write operation). The instruction

word also indicates the starting register address of the first

payload byte.

Data Sheet AD9554-1

Rev. C | Page 45 of 99

Write

If the instruction word indicates a write operation, the payload

is written into the serial control port buffer of the AD9554-1.

Data bits are registered on the rising edge of SCLK. Generally, it

does not matter what data is written to blank registers; however,

it is customary to use 0s. Note that the user must verify that all

reserved registers within a specific range have a default value of

0x00; however, Analog Devices makes every effort to avoid

having reserved registers with nonzero default values.

Most of the serial port registers are buffered (see the

Buffered/Active Registers section for details on the difference

between buffered and active registers). Therefore, data written

into buffered registers does not take effect immediately. An

additional operation is needed to transfer buffered serial control

port contents to the registers that actually control the device.

This transfer is accomplished with an IO_UPDATE operation,

which is performed in one of two ways. One method is to write

a Logic 1 to Register 0x000F, Bit 0 (this bit is an autoclearing

bit). The other method is to use an external signal via an

appropriately programmed multifunction pin. The user can

change as many register bits as desired before executing an

IO_UPDATE. The IO_UPDATE operation transfers the buffer

Read

If the instruction word indicates a read operation, the next

N × 8 SCLK cycles clock out the data starting from the address

specified in the instruction word. N is the number of data bytes

read. The readback data is driven to the pin on the falling edge

and must be latched on the rising edge of SCLK. Blank registers

are not skipped over during readback.

A readback operation takes data from either the serial control

port buffer registers or the active registers, as determined by

SPI Instruction Word (16 Bits)

The MSB of the 16-bit instruction word is R/WE, which indicates

whether the instruction is a read or a write. The next 15 bits are the

address of the read/write operation (see Table 25). Note that A14

and A13 are ignored and treated as zeros in the AD9554-1 because

there are no registers that require more than 13 address bits.

SPI MSB-/LSB-First Transfers

The AD9554-1 instruction word and payload can be MSB first

or LSB first. The default for the AD9554-1 is MSB first. The LSB

first mode can be set by writing a 1 to Register 0x0000, Bit 6.

Immediately after the LSB first bit is set, subsequent serial

control port operations are LSB first.

Address Ascension

If the address ascension bit (Register 0x0000, Bit 5) is zero, the

serial control port register address decrements from the

specified starting address toward Address 0x0000.

If the address ascension bit (Register 0x0000, Bit 5) is one, the

serial control port register address increments from the starting

address toward Address 0x0FFF. Reserved addresses are not

skipped during multibyte input/output operations; therefore,

write the default value to a reserved register and 0s to unmapped

registers. Note that it is more efficient to issue a new write

command than to write the default value to more than two

consecutive reserved (or unmapped) registers.

Table 24. Streaming Mode (No Addresses Skipped)

Address Ascension Stop Sequence

Increment 0x0000 … 0x0FFF

Decrement 0x0FFF … 0x0000

Table 25. Serial Control Port, 16-Bit Instruction Word

MSB LSB

I15 I14 I13 I12 I11 I10 I9 I8 I7 I6 I5 I4 I3 I2 I1 I0

R/W A14 A13 A12 A11 A10 A9 A8 A7 A6 A5 A4 A3 A2 A1 A0

SCLK

DON' T CARE

SDIO A12A13A14R/W A11 A10 A9 A8 A7 A6 A5 A4 A3 A2 A1 A0 D7 D6 D5 D4 D3 D2 D1 D0 D7 D6 D5 D4 D3 D2 D1 D0 DON'T CA RE

DO N' T CARE

DON'T CARE

16-BIT INS TRUCTION HEAD E R REGISTER (N) DATA RE GI S TER (N – 1) DATA

12214-029

Figure 35. Serial Control Port Write—MSB First, Address Decrement, Two Bytes of Data

SCLK

SDIO

A10A11A12A13A14R/W

A8 A7 A6 A5 A4 A3 A2 A1 A0

DON' T CARE

DON'T CARE

D7 D6 D5 D4 D3 D2 D1 D0 D7 D6 D5 D4 D3 D2 D1 D0 D7 D6 D5 D4 D3 D2 D1 D0 D7 D6 D5 D4 D3 D2 D1 D0

12214-030

Figure 36. Serial Control Port Read—MSB First, Address Decrement, Four Bytes of Data

AD9554-1 Data Sheet

Rev. C | Page 46 of 99

DON'T CARE

DON'T CARE A14A13A12A11A10A9A8A7A6A5D4D3D2D1D0

DON'T CARE

R/W

tDS

tDH

tHIGH

tLOW

tCLK tC

SCLK

SDIO

12214-031

Figure 37. Timing Diagram for Serial Control Port Write—MSB First

DATA BIT N – 1DATA BIT N

SCLK

SDIO

12214-032

Figure 38. Timing Diagram for Serial Control Port Register Read—MSB First

SCLK

DON'T CARE

16-BIT INSTRUCTION HEADER REGISTER (N) DATA REGISTER (N + 1) DATA

SDIO DON'T CARE

DON'T CARE

A0 A1 A2 A3 A4 A5 A6 A7 A8 A9 A10 A11 A12 D1D0R/WA14A13 D2 D3 D4 D5 D6 D7 D0 D1 D2 D3 D4 D5 D6 D7

12214-033

Figure 39. Serial Control Port Write—LSB First, Address Increment, Two Bytes of Data

CLK

SDIO

HIGH

LOW

CLK

BIT N BIT N + 1

12214-034

Figure 40. Serial Control Port Timing—Write

Table 26. Serial Control Port Timing

Parameter Description

tDS Setup time between data and the rising edge of SCLK

tDH Hold time between data and the rising edge of SCLK

tCLK Period of the clock

tS Setup time between the CS falling edge and the SCLK rising edge (start of the communication cycle)

tC Setup time between the SCLK rising edge and CS rising edge (end of the communication cycle)

tHIGH Minimum period that SCLK should be in a logic high state

tLOW Minimum period that SCLK should be in a logic low state

tDV SCLK to valid SDIO (see Figure 38)

Data Sheet AD9554-1

Rev. C | Page 47 of 99

I²C SERIAL PORT OPERATION

The I2C interface is popular because it requires only two pins

and easily supports multiple devices on the same bus. Its main

disadvantage is programming speed, which is 400 kbps

maximum. The AD9554-1 IC port design uses the IC fast

mode; however, it supports both the 100 kHz standard mode

and 400 kHz fast mode.

In an effort to support 1.5 V, 1.8 V, and 2.5 V IC operation, the

AD9554-1 does not strictly adhere to every requirement in the

original IC specification. In particular, specifications such as

slew rate limiting and glitch filtering are not implemented.

Therefore, the AD9554-1 is IC compatible, but may not be

fully IC compliant.

The AD9554-1 IC port consists of a serial data line (SDA) and

a serial clock line (SCL). In an IC bus system, the AD9554-1 is

connected to the serial bus (data bus SDA and clock bus SCL) as

a slave device; that is, no clock is generated by the AD9554-1.

The AD9554-1 uses direct 16-bit memory addressing instead of

more common 8-bit memory addressing.

The AD9554-1 allows up to seven unique slave devices to

occupy the I2C bus. These are accessed via a 7-bit slave address

transmitted as part of an I2C packet. Only the device with a

matching slave address responds to subsequent I2C commands.

Table 20 lists the supported device slave addresses.

I2C Bus Characteristics

A summary of the various I2C abbreviations appears in Table 27.

Table 27. I2C Bus Abbreviation Definitions

Abbreviation Definition

S Start

Sr Repeated start

P Stop

A Acknowledge

A Nonacknowledge

W Write

R Read

The transfer of data is shown in Figure 41. One clock pulse is

generated for each data bit transferred. The data on the SDA

line must be stable during the high period of the clock. The

high or low state of the data line can change only when the

clock signal on the SCL line is low.

DATA LINE

STABLE;

DATA VALID

CHANGE

OF DATA

ALLOWED

SDA

SCL

12214-049

Figure 41. Valid Bit Transfer

Start/stop functionality is shown in Figure 42. The start

condition is characterized by a high to low transition on the

SDA line while SCL is high. The master always generates the

start condition to initialize a data transfer. The stop condition is

characterized by a low to high transition on the SDA line while

SCL is high. The master always generates the stop condition to

terminate a data transfer. Every byte on the SDA line must be

eight bits long. Each byte must be followed by an acknowledge

bit; bytes are sent MSB first.

The acknowledge bit (A) is the ninth bit attached to any 8-bit

data byte. An acknowledge bit is always generated by the

receiving device (receiver) to inform the transmitter that the

byte has been received. It is done by pulling the SDA line low

during the ninth clock pulse after each 8-bit data byte.

The nonacknowledge bit (AE) is the ninth bit attached to any 8-

bit data byte. A nonacknowledge bit is always generated by the

receiving device (receiver) to inform the transmitter that the

byte has not been received. It is done by leaving the SDA line

high during the ninth clock pulse after each 8-bit data byte.

After issuing a nonacknowledge bit, the AD9554-1 IC state

machine goes into an idle state.

Data Transfer Process

The master initiates data transfer by asserting a start condition,

which indicates that a data stream follows. All IC slave devices

connected to the serial bus respond to the start condition.

The master then sends an 8-bit address byte over the SDA line,

consisting of a 7-bit slave address (MSB first) plus an R/W bit.

This bit determines the direction of the data transfer, that is,

whether data is written to or read from the slave device (0 =

write and 1 = read).

The peripheral whose address corresponds to the transmitted

address responds by sending an acknowledge bit. All other

devices on the bus remain idle while the selected device waits

for data to be read from or written to it. If the R/W bit is 0, the

master (transmitter) writes to the slave device (receiver). If the

R/W bit is 1, the master (receiver) reads from the slave device

(transmitter).

The format for these commands is described in the Data

Transfer Format section.

Data is then sent over the serial bus in the format of nine clock

pulses, one data byte (eight bits) from either master (write mode)

or slave (read mode) followed by an acknowledge bit from the

receiving device. The number of bytes that can be transmitted

per transfer is unrestricted. In write mode, the first two data

bytes immediately after the slave address byte are the internal

memory (control registers) address bytes, with the high address

byte first. This addressing scheme gives a memory address of up

to 216 − 1 = 65,535. e data bytes aer these two memory address

bytes are register data written to or read from the control registers.

In read mode, the data bytes after the slave address byte are

AD9554-1 Data Sheet

Rev. C | Page 48 of 99

When all the data bytes are read or written, stop conditions are

established. In write mode, the master (transmitter) asserts a

stop condition to end data transfer during the clock pulse

following the acknowledge bit for the last data byte from the

slave device (receiver). In read mode, the master device

(receiver) receives the last data byte from the slave device

(transmitter) but does not pull SDA low during the ninth clock

pulse. This is known as a nonacknowledge bit.

By receiving the nonacknowledge bit, the slave device knows that

the data transfer is finished and enters idle mode. The master

then takes the data line low during the low period before the

10th clock pulse, and high during the 10th clock pulse to assert a

stop condition.

A start condition can be used in place of a stop condition.

Furthermore, a start or stop condition can occur at any time,

and partially transferred bytes are discarded.

SDA

START CONDITION STOP CONDITION

SCL

12214-036

Figure 42. Start and Stop Conditions

12 89123 TO 73 TO 7 89

SDA

SCL

MSB

ACK FROM

SLAVE RECEIVER

ACK FROM

SLAVE RECEIVER

12214-037

Figure 43. Acknowledge Bit

12 89123 TO 73 TO 7 8910

ACK FROM

SLAVE RECEIVER ACK FROM

SLAVE RECEIVER

SDA

SCL

MSB

12214-038

Figure 44. Data Transfer Process (Master Write Mode, 2-Byte Transfer)

12 89123 TO 73 TO 7 8910

ACK FROM

MASTER RECEIVER NONACK FROM

MASTER RECEIVER

SDA

SCL

12214-039

Figure 45. Data Transfer Process (Master Read Mode, 2-Byte Transfer), First Acknowledge From Slave

Data Sheet AD9554-1

Rev. C | Page 49 of 99

Data Transfer Format

The write byte format is used to write a register address to the RAM starting from the specified RAM address.

S Slave

address

W A RAM address high byte A RAM address low byte A RAM

Data 0

A RAM

Data 1

A RAM

Data 2

A P

The send byte format is used to set up the register address for subsequent reads.

S Slave address W A RAM address high byte A RAM address low byte A P

The receive byte format is used to read the data byte(s) from RAM starting from the current address.

S Slave address R A RAM Data 0 A RAM Data 1 A RAM Data 2 A P

The read byte format is the combined format of the send byte and the receive byte.

S Slave

address

W A RAM address

high byte

A RAM address

low byte

A Sr Slave

address

R A RAM

Data 0

A RAM

Data 1

A RAM

Data 2

A P

I²C Serial Port Timing

SSr SP

SCL

HD; STA

SU; STA

SU; DAT

HD; DAT

HD; STA

SU; STO

BUF

HIGH

LOW

12214-040

Figure 46. I²C Serial Port Timing

Table 28. IC Timing Definitions

Parameter Description

fSCL Serial clock

tBUF Bus free time between stop and start conditions

tHD; STA Repeated hold time start condition

tSU; STA Repeated start condition setup time

tSU; STO Stop condition setup time

tHD; DAT Data hold time

tSU; DAT Data setup time

tLOW SCL clock low period

tHIGH SCL clock high period

tR Minimum/maximum receive SCL and SDA rise time

tF Minimum/maximum receive SCL and SDA fall time

tSP Pulse width of voltage spikes that must be suppressed by the input filter

AD9554-1 Data Sheet

Rev. C | Page 50 of 99

PROGRAMMING THE I/O REGISTERS

The register map (see Table 31) spans an address range from

0x0000 through 0x1788. Each address provides access to one byte

(eight bits) of data. Each individual register is identified by its

four digit hexadecimal address (for example, Register 0x0A23).

In some cases, a group of addresses collectively defines a register.

In general, when a group of registers defines a control parameter,

the LSB of the value resides in the D0 position of the register

with the lowest address. The bit weight increases right to left,

from the lowest register address to the highest register address.

BUFFERED/ACTIVE REGISTERS

There are two copies of most registers: buffered and active. The

value in the active registers is the one that is in use. The buffered

registers are the ones that take effect the next time the user writes

0x01 to Register 0x000F (IO_UPDATE). Buffering the registers

allows the user to update a group of registers (like the APLL

settings) simultaneously, avoiding the potential of unpredictable

behavior in the device. Registers with an L in the option column

of the register map (see Table 31) are live, meaning that they

take effect the moment the serial port transfers that data byte.

WRITE DETECT REGISTERS

A Wx (where x equals 1 to 8) in the option column of the

detection. These registers contain additional logic to avoid

glitches or unwanted operation.

Table 29. Register Write Detection Description

Option Register Operation

W1 When these registers are written to, the lock detector

immediately declares it is unlocked. The lock detection

restarts when the next IO_UPDATE occurs.

W2 After these registers are written to, the DPLL faults

the reference input and automatically enters holdover

for one PFD cycle (and then exits) when an

IO_UPDATE is issued. However, this action is only

performed if the written register belongs to the

actively selected reference.

W3 After these registers are written to, the DPLL lock

detector unlocks.

W5 The watchdog timer resets automatically when

these registers are written to and then resumes

counting on the next IO_UPDATE.

W6 The system clock stability timer is automatically

reset when these registers are changed and then

resumes counting on the next IO_UPDATE. (Note

that the SYSCLK stability timer starts only after the

system clock is locked.

W7 If these registers are written to while they are

assigned to an existing function, the existing

function stops immediately. The new function starts

when the next IO_UPDATE occurs.

W8 Almost identical to W2; however, the DPLL must be

in demapping mode.

AUTOCLEAR REGISTERS

An A in the option column of the register map (see

Table 31) identifies an autoclearing register. Typically, the active

value for an autoclearing register takes effect following an

IO_UPDATE. The bit is cleared by the internal device logic

upon completion of the prescribed action.

Read and write access to the register map may be restricted,

depending on the register in question, the source and direction

of access, and the current state of the device. Each register can

be classified into one or more access types. When more than

one type applies, the most restrictive condition is the one that

applies.

When access is denied to a register, all attempts to read the

are ignored. Access to nonexistent registers is handled in the

same way as for a denied register.

Regular Access

Registers with regular access do not fall into any other category.

Read Only Access

An R in the option column of the register map (see

Table 31) identifies read only registers. Serial port access is

available at all times.

Data Sheet AD9554-1

Rev. C | Page 51 of 99

THERMAL PERFORMANCE

Table 30. Thermal Parameters for the 56-Lead LFCSP Package

Symbol Thermal Characteristic Using a JEDEC 51-7 Plus JEDEC 51-5 2S2P Test Board1 Value2 Unit

θJA Junction-to-ambient thermal resistance, 0.0 m/sec airflow per JEDEC JESD51-2 (still air) 25.3 °C/W

θJMA Junction-to-ambient thermal resistance, 1.0 m/sec airflow per JEDEC JESD51-6 (moving air) 21.8 °C/W

θJMA Junction-to-ambient thermal resistance, 2.5 m/sec airflow per JEDEC JESD51-6 (moving air) 20.4 °C/W

θJB Junction-to-board thermal resistance, 0.0 m/sec airflow per JEDEC JESD51-8 (still air) 10.9 °C/W

θJC Junction-to-case thermal resistance (die-to-heat sink) per MIL-Standard 883, Method 1012.1 2.64 °C/W

ΨJT Junction-to-top-of-package characterization parameter, 0 m/sec airflow per JEDEC JESD51-2 (still air) 0.16 °C/W

ΨJT Junction-to-top-of-package characterization parameter, 1.0 m/sec airflow per JEDEC JESD51-6 (moving air) 0.29 °C/W

ΨJT Junction-to-top-of-package characterization parameter, 2.5 m/sec airflow per JEDEC JESD51-6 (moving air) 0.37 °C/W

1 The exposed pad on the bottom of the package must be soldered to analog ground of the PCB to achieve the specified thermal performance.

2 Results are from simulations. The PCB is a JEDEC multilayer type. Thermal performance for actual applications requires careful inspection of the conditions in the

application to determine if they are similar to those assumed in these calculations.

The AD9554-1 is specified for a case temperature (TCASE). To

ensure that TCASE is not exceeded, an airflow source can be used.

Use the following equation to determine the junction temperature

on the application PCB:

TJ = TCASE + (ΨJT × PD)

where:

TJ is the junction temperature (°C).

TCASE is the case temperature (°C) measured by the customer at

the top center of the package.

ΨJT is the value as indicated in Table 30.

PD is the power dissipation (see Table 3).

Valu es of θJA are provided for package comparison and PCB

design considerations. θJA can be used for a first-order

approximation of TJ by the equation

TJ = TA + (θJA × PD)

where TA is the ambient temperature (°C).

Valu es of θJC are provided for package comparison and PCB

design considerations when an external heat sink is required.

Valu es of θJB are provided for package comparison and PCB

design considerations.

AD9554-1 Data Sheet

Rev. C | Page 52 of 99

POWER SUPPLY PARTITIONS

The AD9554-1 power supplies are in two groups: VDD and

VDD_SP. All power and ground pins must be connected, even

if certain blocks of the chip are powered down.

VDD SUPPLIES

All of the VDD supplies can be connected to one common

source that is either 1.5 V or 1.8 V.

Place the 0.1 µF bypass capacitors as close as possible to each

power supply pin.

In addition to these bypass capacitors, the AD9554-1 evaluation

board uses four ferrite beads between the 1.8 V (or 1.5 V) source

and Pin 15, Pin 28, Pin 43, and Pin 56.

Although these ferrite beads may not be needed for every

application, the use of these ferrite beads is strongly recommended.

At a minimum, include a place for the ferrite beads (as close to

the bypass capacitors as possible) and populate the board with

0402, 0 Ω resistors. By doing so, there is a place for the ferrite

beads, if needed.

The ferrite beads are required if the AD9554-1 is powered

directly from a switching power supply.

Ferrite beads with low (<0.7 Ω) dc resistance and approximately

30 Ω impedance at 100 MHz are suitable for this application.

For example, the Murata BLM15AX300SN1D is suitable.

VDD_SP SUPPLY

Pin 23 (VDD_SP) is the serial port power supply pin and can be

connected to a 2.5 V, 1.8 V, or 1.5 V power supply.

If the user needs to operate the serial port at the same voltage as

the device itself, VDD_SP can be joined to VDD.

Data Sheet AD9554-1

Rev. C | Page 53 of 99

Register addresses that are not listed in Table 31 are not used, and writing to those registers has no effect. Write the default value to

sections of registers marked reserved. In the option column, R = read only; A = autoclear; W1, W2, W3, W5, W6, W7, and W8 = write

detection (see Table 29 for more information); and L = live (IO_UPDATE not required for register to take effect or for a read only register

to be updated). N/A = not applicable.

Table 31.

Reg.

Addr.

(Hex) Option Name D7 D6 D5 D4 D3 D2 D1 D0

Def

(Hex)

Serial Control Port and Part Identification

0x0000 L SPI Config A Soft reset LSB first

(SPI only)

Address

ascension

(SPI only)

Reserved Address

ascension

(SPI only)

LSB first

(SPI only)

Soft reset 0x00

0x0001 L SPI Config B Reserved Read buffer

Reserved Reset sans

regmap

Reserved 0x00

0x0002 Reserved Reserved 0x00

0x0003 R Chip type Reserved Chip type, Bits[3:0] 0x05

0x0004 R Product ID Clock part serial ID, Bits[3:0] Reserved 0x9F

0x0005 R Clock part serial ID, Bits[11:4] 0x00

0x0006 R Revision Part version, Bits[7:0] 0x05

0x0007 Reserved Reserved 0x00

0x0008 Reserved Reserved 0x00

0x0009 Reserved Reserved 0x00

0x000A Reserved Reserved 0x00

0x000B R SPI version SPI version, Bits[7:0] 0x00

0x000C R Vendor ID Vendor ID, Bits[7:0] 0x56

0x000D R Vendor ID, Bits[15:8] 0x04

0x000E Reserved Reserved 0x00

0x000F L, A IO_UPDATE Reserved IO_UPDATE 0x00

General Configuration

0x0100 Mx pin

drivers

M3 driver mode, Bits[1:0] M2 driver mode, Bits[1:0] M1 driver mode, Bits[1:0] M0 driver mode, Bits[1:0] 0x00

0x0101 M7 driver mode, Bits[1:0] M6 driver mode, Bits[1:0] M5 driver mode, Bits[1:0] Reserved 0x00

0x0102 Reserved 0x00

0x0103 W7 M0FUNC M0 output/

inputE

M0 function, Bits[6:0] 0x00

0x0104 W7 M1FUNC M1 output/

inputE

M1 function, Bits[6:0] 0x00

0x0105 W7 M2FUNC M2 output/

inputE

M2 function, Bits[6:0] 0x00

0x0106 W7 M3FUNC M3 output/

inputE

M3 function, Bits[6:0] 0x00

0x0107 W7 Reserved Reserved 0x00

0x0108 W7 M5FUNC M5 output/

inputE

M5 function, Bits[6:0] 0x00

0x0109 W7 M6FUNC M6 output/

inputE

M6 function, Bits[6:0] 0x00

0x010A W7 M7FUNC M7 output/

inputE

M7 function, Bits[6:0] 0x00

0x010B W7 Reserved Reserved 0x00

0x010C W7 Reserved Reserved 0x00

0x010D W5 Watchdog

timer

Watchdog timer (ms), Bits[7:0] 0x00

0x010E W5 Watchdog timer (ms), Bits[15:8] 0x00

0x010F IRQ mask

common

SYSCLK

unlocked

SYSCLK

stable

SYSCLK

locked

SYSCLK

calibration

ended

SYSCLK

calibration

started

Watchdog

timer

Reserved 0x00

0x0110 Reserved REFB

validated

REFB fault

cleared

REFB fault Reserved REFA

validated

REFA fault

cleared

REFA fault 0x00

0x0111 Reserved REFD

validated

REFD fault

cleared

REFD fault Reserved REFC

validated

REFC fault

cleared

REFC fault 0x00

AD9554-1 Data Sheet

Rev. C | Page 54 of 99

Reg.

Addr.

(Hex) Option Name D7 D6 D5 D4 D3 D2 D1 D0

Def

(Hex)

0x0112 IRQ mask

DPLL_0

Frequency

unclamped

Frequency

clamped

Phase slew

unlimited

Phase slew

limited

Frequency

unlocked

Frequency

locked

Phase

unlocked

Phase

locked

0x00

0x0113 Switching Free run Holdover History

updated

REFD

activated

REFC

activated

REFB

activated

REFA

activated

0x00

0x0114 Phase step

detected

Demap

controller

unclamped

Demap

controller

clamped

Sync clock

distribution

APLL_0

unlocked

APLL_0

locked

APLL_0 cal

complete

APLL_0 cal

started

0x00

0x0115 IRQ mask

DPLL_1

Frequency

unclamped

Frequency

clamped

Phase slew

unlimited

Phase slew

limited

Frequency

unlocked

Frequency

locked

Phase

unlocked

Phase

locked

0x00

0x0116 Switching Free run Holdover History

updated

REFD

activated

REFC

activated

REFB

activated

REFA

activated

0x00

0x0117 Phase step

detected

Demap

controller

unclamped

Demap

controller

clamped

Sync clock

distribution

APLL_1

unlocked

APLL_1

locked

APLL_1 cal

complete

APLL_1 cal

started

0x00

0x0118 IRQ mask

DPLL_2

Frequency

unclamped

Frequency

clamped

Phase slew

unlimited

Phase slew

limited

Frequency

unlocked

Frequency

locked

Phase

unlocked

Phase

locked

0x00

0x0119 Switching Free run Holdover History

updated

REFD

activated

REFC

activated

REFB

activated

REFA

activated

0x00

0x011A Phase step

detected

Demap

controller

unclamped

Demap

controller

clamped

Sync clock

distribution

APLL_2

unlocked

APLL_2

locked

APLL_2 cal

complete

APLL_2 cal

started

0x00

0x011B IRQ mask

DPLL_3

Frequency

unclamped

Frequency

clamped

Phase slew

unlimited

Phase slew

limited

Frequency

unlocked

Frequency

locked

Phase

unlocked

Phase

locked

0x00

0x011C Switching Free run Holdover History

updated

REFD

activated

REFC

activated

REFB

activated

REFA

activated

0x00

0x011D Phase step

detected

Demap

controller

unclamped

Demap

controller

clamped

Sync clock

distribution

APLL_3

unlocked

APLL_3

locked

APLL_3 cal

complete

APLL_3

cal started

0x00

0x011E L Pad control M7 config M6 config M5 config Reserved M3 config M2 config M1 config M0 config 0x00

0x011F L Reserved SPI config Reserved 0x00

System Clock

0x0200 SYSCLK PLL

feedback

divider and

configuration

System clock K divider, Bits[7:0] 0x00

0x0201 Reserved SYSCLK

XTAL

enable

SYSCLK J1 divider, Bits[1:0] SYSCLK

doubler

enable

(J0 divider)

0x08

0x0202 W6 SYSCLK

reference

frequency

System clock reference frequency (Hz), Bits[7:0] 0x00

0x0203 W6 System clock reference frequency (Hz), Bits[15:8] 0x00

0x0204 W6 System clock reference frequency (Hz), Bits[23:16] 0x00

0x0205 W6 Reserved System clock reference frequency (Hz), Bits[27:24] 0x00

0x0206 W6 SYSCLK

stability

System clock stability period (ms), Bits[7:0] 0x32

0x0207 W6 System clock stability period (ms), Bits[15:8] 0x00

0x0208 W6 Reserved System clock stability period (ms), Bits[19:16] 0x00

Reference Input A

0x0300 W1, L REFA logic

type

Reserved REFA logic type, Bits[1:0] 0x00

0x0301 W1, L REFA

R divider

(20 bits)

R divider, Bits[7:0] 0x00

0x0302 W1, L R divider, Bits[15:8] 0x00

0x0303 W1, L Reserved R divider, Bits[19:16] 0x00

0x0304 W2, L REFA period Nominal reference period (fs), Bits[7:0] 0x00

0x0305 W2, L Nominal reference period (fs), Bits[15:8] 0x00

0x0306 W2, L Nominal reference period (fs), Bits[23:16] 0x00

0x0307 W2, L Nominal reference period (fs), Bits[31:24] 0x00

0x0308 W2, L Nominal reference period (fs), Bits[39:32] 0x00

0x0309 W2, L REFA

frequency

tolerance

Inner tolerance (1/(ppm error)), Bits[7:0] (for invalid to valid condition; maximum: 6.55%, minimum: 2 ppm) (default: 5%) 0x14

0x030A W2, L Inner tolerance (1/(ppm error)), Bits[15:8] (for invalid to valid condition; maximum: 6.55%, minimum: 2 ppm) 0x00

0x030B W2, L Reserved Inner tolerance (1/(ppm error)), Bits[19:16] 0x00

0x030C W2, L Outer tolerance (1/(ppm error)), Bits[7:0] (for valid to invalid; maximum: 6.55%, minimum: 2 ppm) (default: 10%) 0x0A

0x030D W2, L Outer tolerance (1/(ppm error)), Bits[15:8] (for valid to invalid; max: 6.55%, min: 2 ppm) 0x00

0x030E W2, L Reserved Outer tolerance (1/(ppm error)), Bits[19:16] 0x00

0x030F W2, L REFA

validation

timer

Validation timer (ms), Bits[7:0] (up to 65.5 sec) 0x0A

0x0310 W2, L Validation timer (ms), Bits[15:8] (up to 65.5 sec) 0x00

Data Sheet AD9554-1

Rev. C | Page 55 of 99

Reg.

Addr.

(Hex) Option Name D7 D6 D5 D4 D3 D2 D1 D0

Def

(Hex)

0x0311 W3, L REFA

phase lock

detector

Phase lock threshold (ps), Bits[7:0] 0xBC

0x0312 W3, L Phase lock threshold (ps), Bits[15:8] 0x02

0x0313 W3, L Phase lock threshold (ps), Bits [23:16] 0x00

0x0314 W3, L Phase lock fill rate, Bits[7:0] 0x0A

0x0315 W3, L Phase lock drain rate, Bits[7:0] 0x0A

0x0316 W3, L REFA

frequency

lock

detector

Frequency lock threshold (ps), Bits[7:0] 0xBC

0x0317 W3, L Frequency lock threshold (ps), Bits[15:8] 0x02

0x0318 W3, L Frequency lock threshold (ps), Bits[23:16] 0x00

0x0319 W3, L Frequency lock fill rate, Bits[7:0] 0x0A

0x031A W3, L Frequency lock drain rate, Bits[7:0] 0x0A

0x031B W3, L REFA phase

step

threshold

Phase step threshold (ps), Bits[7:0] 0x00

0x031C W3, L Phase step threshold (ps), Bits[15:8] 0x00

0x031D W3, L Phase step threshold (ps), Bits[23:16] 0x00

0x031E W3, L Reserved Phase step threshold (ps), Bits[27:24] 0x00

Reference Input B

0x0320

0x033E

These registers mimic the Reference Input A registers (0x0300 through 0x031E) but the register addresses are offset by

0x0020. All default values are identical.

Reference Input C

0x0340

0x035E

These registers mimic the Reference Input A registers (0x0300 through 0x031E) but register addresses are offset by

0x0040. All default values are identical.

Reference Input D

0x0360

0x037E

These registers mimic the Reference Input A registers (0x0300 through 0x031E) but the register addresses are offset by

0x0060. All default values are identical.

DPLL_0 General Settings

0x0400 DPLL_0

free run

frequency

30-bit free running frequency tuning word, Bits[7:0] 0x00

0x0401 30-bit free running frequency tuning word, Bits[15:8] 0x00

0x0402 30-bit free running frequency tuning word, Bits[23:16] 0x00

0x0403 Reserved 30-bit free running frequency tuning word, Bits[29:24] 0x00

0x0404 DPLL_0

DCO integer

Reserved DCO integer, Bits[3:0] 0x17

0x0405 DPLL_0

frequency

clamp

Lower limit of pull-in range, Bits[7:0] 0xCC

0x0406 Lower limit of pull-in range, Bits[15:8] 0xCC

0x0407 Reserved Lower limit of pull-in range, Bits[19:16] 0x00

0x0408 Upper limit of pull-in range, Bits[7:0] 0x33

0x0409 Upper limit of pull-in range, Bits[15:8] 0x33

0x040A Reserved Upper limit of pull-in range, Bits[19:16] 0x0F

0x040B DPLL_0

holdover

history

History accumulation timer (ms), Bits[7:0] (up to 65 sec) 0x0A

0x040C History accumulation timer (ms), Bits[15:8] (up to 65 sec) 0x00

0x040D DPLL_0

history

mode

Reserved Single

sample

fallback

Persistent

history

Incremental average, Bits [2:0] 0x00

0x040E DPLL_0

closed loop

phase offset

(±0.5 ms)

Fixed phase offset (signed; ps), Bits[7:0] 0x00

0x040F Fixed phase offset (signed; ps), Bits[15:8] 0x00

0x0410 Fixed phase offset (signed; ps), Bits[23:16] 0x00

0x0411 Reserved Fixed phase offset (signed; ps), Bits[29:24] 0x00

0x0412 Incremental phase offset step size (ps/step), Bits[7:0] (up to 65.5 ns/step) 0x00

0x0413 Incremental phase offset step size (ps/step), Bits[15:8] (up to 65.5 ns/step) 0x00

0x0414 DPLL_0

phase

slew limit

Phase slew rate limit (μs/sec), Bits[7:0] (315 μs/sec up to 65.536 ms/sec) 0x00

0x0415 Phase slew rate limit (μs/sec), Bits[15:8] (315 μs/sec up to 65.536 ms/sec) 0x00

0x0416 Demap

enable

Reserved Enable

demap

controller

0x00

AD9554-1 Data Sheet

Rev. C | Page 56 of 99

Reg.

Addr.

(Hex) Option Name D7 D6 D5 D4 D3 D2 D1 D0

Def

(Hex)

0x0417 Demap

sampled

address

Sampled address, Bits[7:0] 0x00

0x0418 Sampled address, Bits[15:8] 0x00

0x0419 Demap

set point

address

Set point address, Bits[7:0] 0x00

0x041A Set point address, Bits[15:8] 0x00

0x041B Demap

gain control

Gain, Bits[7:0] 0x00

0x041C Gain, Bits[15:8] 0x00

0x041D Gain, Bits[23:16] 0x00

0x041E Demap

clamp

control

Clamp value, Bits[7:0] 0x00

Output PLL_0 (APLL_0) and Channel 0 Output Drivers

0x0430 APLL_0

charge

pump

Reserved Output PLL0 (APLL_0) charge pump current, Bits[6:0] 0x2E

0x0431 APLL_0

M0 divider

Output PLL0 (APLL_0) feedback (M0) divider, Bits[7:0] 0x00

0x0432 APLL_0

loop filter

control

APLL_0 loop filter control, Bits[7:0] 0x7F

0x0433 Reserved P0 divider reset APLL_0

loop filter

control,

Bit 8

0x00

0x0434 P0 divider Reserved P0 divider divide ratio, Bits[3:0] 0x00

0x0435 OUT0 sync Reserved Sync source

selection

Auto sync mode, Bits[1:0] 0x00

0x0436 Reserved APLL_0

mask sync

Mask

OUT0B

sync

Reserved 0x00

0x0437 Reserved Reserved 0x00

0x0438 Reserved 0x00

0x0439 Reserved 0x00

0x043A Reserved 0x00

0x043B OUT0B Reserved OUT0B mode, Bits[1:0] Invert

polarity

0x08

0x043C Q0_B

divider

Q0_B divider, Bits[7:0] 0x00

0x043D Reserved Q0_B divider, Bits[9:8] 0x00

0x043E Reserved Q0_B divider phase, Bits[5:0] 0x00

DPLL_0 Settings for Reference Input A

0x0440 Reference

priority

Reserved REFA priority, Bits[1:0] Enable

REFA

0x00

0x0441 W2, L DPLL_0

loop BW

(17 bits)

Digital PLL_0 loop bandwidth scaling factor, Bits[7:0] (unit of 0.1 Hz) 0x00

0x0442 W2, L Digital PLL_0 loop bandwidth scaling factor, Bits[15:8] (unit of 0.1 Hz) 0x00

0x0443 W2, L Reserved Base loop

filter

selection

Digital

PLL_0 loop

BW scaling

factor,

Bit 16

0x00

0x0444 W2 DPLL_0

N0 divider

(18 bits)

Digital PLL_0 feedback divider—Integer Part N0, Bits[7:0] 0x00

0x0445 W2 Digital PLL_0 feedback divider—Integer Part N0, Bits[15:8] 0x00

0x0446 W2 Reserved Digital PLL_0 feedback

divider—Integer Part N0,

Bits[17:16]

0x00

0x0447 W8 DPLL_0

fractional

feedback

divider

(24 bits)

Digital PLL_0 fractional feedback divider—FRAC0, Bits[7:0] 0x00

0x0448 W8 Digital PLL_0 fractional feedback divider—FRAC0, Bits[15:8] 0x00

0x0449 W8 Digital PLL_0 fractional feedback divider—FRAC0, Bits[23:16] 0x00

0x044A W2 DPLL_0

fractional

feedback

divider

modulus

(24 bits)

Digital PLL_0 feedback divider modulus—MOD0, Bits[7:0] 0x00

0x044B W2 Digital PLL_0 feedback divider modulus—MOD0, Bits[15:8] 0x00

0x044C W2 Digital PLL_0 feedback divider modulus—MOD0, Bits[23:16] 0x00

Data Sheet AD9554-1

Rev. C | Page 57 of 99

Reg.

Addr.

(Hex) Option Name D7 D6 D5 D4 D3 D2 D1 D0

Def

(Hex)

DPLL_0 Settings for Reference Input B

0x044D Reference

priority

Reserved REFB priority, Bits[1:0] Enable

REFB

0x00

0x044E W2, L DPLL_0

loop BW

(17 bits)

Digital PLL_0 loop bandwidth scaling factor, Bits[7:0] (unit of 0.1 Hz) 0x00

0x044F W2, L Digital PLL_0 loop bandwidth scaling factor, Bits[15:8] (unit of 0.1 Hz) 0x00

0x0450 W2, L Reserved Base loop

filter

selection

Digital

PLL_0 loop

BW scaling

factor,

Bit 16

0x00

0x0451 W2 DPLL_0

N0 divider

(18 bits)

Digital PLL_0 feedback divider—Integer Part N0, Bits[7:0] 0x00

0x0452 W2 Digital PLL_0 feedback divider—Integer Part N0, Bits[15:8] 0x00

0x0453 W2 Reserved Digital PLL_0 feedback

divider—Integer Part N0,

Bits[17:16]

0x00

0x0454 W8 DPLL_0

fractional

feedback

divider

(24 bits)

Digital PLL_0 fractional feedback divider—FRAC0, Bits[7:0] 0x00

0x0455 W8 Digital PLL_0 fractional feedback divider—FRAC0, Bits[15:8] 0x00

0x0456 W8 Digital PLL_0 fractional feedback divider—FRAC0, Bits[23:16] 0x00

0x0457 W2 DPLL_0

fractional

feedback

divider

modulus

(24 bits)

Digital PLL_0 feedback divider modulus—MOD0, Bits[7:0] 0x00

0x0458 W2 Digital PLL_0 feedback divider modulus—MOD0, Bits[15:8] 0x00

0x0459 W2 Digital PLL_0 feedback divider modulus—MOD0, Bits[23:16] 0x00

DPLL_0 Settings for Reference Input C

0x045A Reference

priority

Reserved REFC priority, Bits[1:0] Enable

REFC

0x00

0x045B W2, L DPLL_0

loop BW

(17 bits)

Digital PLL_0 loop bandwidth scaling factor, Bits[7:0] (unit of 0.1 Hz) 0x00

0x045C W2, L Digital PLL_0 loop bandwidth scaling factor, Bits[15:8] (unit of 0.1 Hz) 0x00

0x045D W2, L Reserved Base loop

filter

selection

Digital

PLL_0 loop

BW scaling

factor,

Bit 16

0x00

0x045E W2 DPLL_0

N0 divider

(18 bits)

Digital PLL_0 feedback divider—Integer Part N0, Bits[7:0] 0x00

0x045F W2 Digital PLL_0 feedback divider—Integer Part N0, Bits[15:8] 0x00

0x0460 W2 Reserved Digital PLL_0 feedback

divider—Integer Part N0,

Bits[17:16]

0x00

0x0461 W8 DPLL_0

fractional

feedback

divider

(24 bits)

Digital PLL_0 fractional feedback divider—FRAC0, Bits[7:0] 0x00

0x0462 W8 Digital PLL_0 fractional feedback divider—FRAC0, Bits[15:8] 0x00

0x0463 W8 Digital PLL_0 fractional feedback divider—FRAC0, Bits[23:16] 0x00

0x0464 W2 DPLL_0

fractional

feedback

divider

modulus

(24 bits)

Digital PLL_0 feedback divider modulus—MOD0, Bits[7:0] 0x00

0x0465 W2 Digital PLL_0 feedback divider modulus—MOD0, Bits[15:8] 0x00

0x0466 W2 Digital PLL_0 feedback divider modulus—MOD0, Bits[23:16] 0x00

DPLL_0 Settings for Reference Input D

0x0467 Reference

priority

Reserved REFD priority, Bits[1:0] Enable

REFD

0x00

0x0468 W2, L DPLL_0

loop BW

(17 bits)

Digital PLL_0 loop bandwidth scaling factor, Bits[7:0] (unit of 0.1 Hz) 0x00

0x0469 W2, L Digital PLL_0 loop bandwidth scaling factor, Bits[15:8] (unit of 0.1 Hz) 0x00

0x046A W2, L Reserved Base loop

filter

selection

Digital

PLL_0 loop

BW scaling

factor,

Bit 16

0x00

0x046B W2 DPLL_0

N0 divider

(18 bits)

Digital PLL_0 feedback divider—Integer Part N0, Bits[7:0] 0x00

0x046C W2 Digital PLL_0 feedback divider—Integer Part N0, Bits[15:8] 0x00

0x046D W2 Reserved Digital PLL_0 feedback

divider—Integer Part N0,

Bits[17:16]

0x00

AD9554-1 Data Sheet

Rev. C | Page 58 of 99

Reg.

Addr.

(Hex) Option Name D7 D6 D5 D4 D3 D2 D1 D0

Def

(Hex)

0x046E W8 DPLL_0

fractional

feedback

divider

(24 bits)

Digital PLL_0 fractional feedback divider—FRAC0, Bits[7:0] 0x00

0x046F W8 Digital PLL_0 fractional feedback divider—FRAC0, Bits[15:8] 0x00

0x0470 W8 Digital PLL_0 fractional feedback divider—FRAC0, Bits[23:16] 0x00

0x0471 W2 DPLL_0

fractional

feedback

divider

modulus

(24 bits)

Digital PLL_0 feedback divider modulus—MOD0, Bits[7:0] 0x00

0x0472 W2 Digital PLL_0 feedback divider modulus—MOD0, Bits[15:8] 0x00

0x0473 W2 Digital PLL_0 feedback divider modulus—MOD0, Bits[23:16] 0x00

DPLL_1 General Settings

0x0500

0x051E

These registers mimic the DPLL_0 general settings registers (0x0400 through 0x041E) but the register addresses are

offset by 0x0100. All default values are identical.

Output PLL_1 (APLL_1) and Channel 1 Output Drivers

0x0530

0x053E

These registers mimic the output PLL_0 (APLL_0) general settings registers (0x0430 through 0x043E) but the register

addresses are offset by 0x0100. All default values are identical.

DPLL_1 Settings for Reference Input A

0x0540

0x054C

These registers mimic the DPLL_0 settings for Reference Input A registers (0x0440 through 0x044C) but the register

addresses are offset by 0x0100. All default values are identical.

DPLL_1 Settings for Reference Input B

0x054D

0x0559

These registers mimic the DPLL_0 settings for Reference Input B registers (0x044D through 0x0459) but the register

addresses are offset by 0x0100. All default values are identical.

DPLL_1 Settings for Reference Input C

0x055A

0x0566

These registers mimic the DPLL_0 settings for Reference Input C registers (0x045A through 0x0466) but the register

addresses are offset by 0x0100. All default values are identical.

DPLL_1 Settings for Reference Input D

0x0567

0x0573

These registers mimic the DPLL_0 settings for Reference Input D registers (0x0467 through 0x0473) but the register

addresses are offset by 0x0100. All default values are identical.

DPLL_2 General Settings

0x0600

0x061E

These registers mimic the DPLL_0 general settings registers (0x0400 through 0x041E) but the register addresses are

offset by 0x0200. All default values are identical.

Output PLL_2 (APLL_2) and Channel 2 Output Drivers

0x0630

0x063E

These registers mimic the output PLL_0 (APLL_0) general settings registers (0x0430 through 0x043E) but the register

addresses are offset by 0x0200. All default values are identical.

DPLL_2 Settings for Reference Input A

0x0640

0x064C

These registers mimic the DPLL_0 settings for Reference Input A registers (0x0440 through 0x044C) but the register

addresses are offset by 0x0200. All default values are identical.

DPLL_2 Settings for Reference Input B

0x064D

0x0659

These registers mimic the DPLL_0 settings for Reference Input B registers (0x044D through 0x0459) but the register

addresses are offset by 0x0200. All default values are identical.

DPLL_2 Settings for Reference Input C

0x065A

0x0666

These registers mimic the DPLL_0 settings for Reference Input C registers (0x045A through 0x0466) but the register

addresses are offset by 0x0200. All default values are identical.

DPLL_2 Settings for Reference Input D

0x0667

0x0673

These registers mimic the DPLL_0 settings for Reference Input D registers (0x0467 through 0x0473) but the register

addresses are offset by 0x0200. All default values are identical.

DPLL_3 General Settings

0x0700

0x071E

These registers mimic the DPLL_0 general settings registers (0x0400 through 0x041E) but the register addresses are

offset by 0x0300. All default values are identical.

Output PLL_3 (APLL_3) and Channel 3 Output Drivers

Data Sheet AD9554-1

Rev. C | Page 59 of 99

Reg.

Addr.

(Hex) Option Name D7 D6 D5 D4 D3 D2 D1 D0

Def

(Hex)

0x0730

0x073E

These registers mimic the output PLL_0 (APLL_0) general settings registers (0x0430 through 0x043E) but the register

addresses are offset by 0x0300. All default values are identical.

DPLL_3 Settings for Reference Input A

0x0740

0x074C

These registers mimic the DPLL_0 settings for Reference Input A registers (0x0440 through 0x044C) but the register

addresses are offset by 0x0300. All default values are identical.

DPLL_3 Settings for Reference Input B

0x074D

0x0759

These registers mimic the DPLL_0 settings for Reference Input B registers (0x044D through 0x0459) but the register

addresses are offset by 0x0300. All default values are identical.

DPLL_3 Settings for Reference Input C

0x075A

0x0766

These registers mimic the DPLL_0 Settings for Reference Input C registers (0x045A through 0x0466) but the register

addresses are offset by 0x0300. All default values are identical.

DPLL_3 Settings for Reference Input D

0x0767

0x0773

These registers mimic the DPLL_0 Settings for Reference Input D registers (0x0467 through 0x0473) but the register

addresses are offset by 0x0300. All default values are identical.

Digital Loop Filter Coefficients

0x0800 L Base loop

filter

coefficient

set (normal

phase

margin of

70°)

NPM Alpha-0 linear, Bits[7:0] 0x24

0x0801 L NPM Alpha-0 linear, Bits[15:8] 0x8C

0x0802 L Reserved NPM Alpha-1 exponent, Bits[6:0] 0x49

0x0803 L NPM Beta-0 linear, Bits[7:0] 0x55

0x0804 L NPM Beta-0 linear, Bits[15:8] 0xC9

0x0805 L Reserved NPM Beta-1 exponent, Bits[6:0] 0x7B

0x0806 L NPM Gamma-0 linear, Bits[7:0] 0x9C

0x0807 L NPM Gamma-0 linear, Bits[15:8] 0xFA

0x0808 L Reserved NPM Gamma-1 exponent, Bits[6:0] 0x55

0x0809 L NPM Delta-0 linear, Bits[7:0] 0xEA

0x080A L NPM Delta-0 linear, Bits[15:8] 0xE2

0x080B L Reserved NPM Delta-1 exponent, Bits[6:0] 0x57

0x080C L Base loop

filter

coefficient

set (high

phase

margin)

HPM Alpha-0 linear, Bits[7:0] 0x8C

0x080D L HPM Alpha-0 linear, Bits[15:8] 0xAD

0x080E L Reserved HPM Alpha-1 exponent, Bits[6:0] 0x4C

0x080F L HPM Beta-0 linear, Bits[7:0] 0xF5

0x0810 L HPM Beta-0 linear, Bits[15:8] 0xCB

0x0811 L Reserved HPM Beta-1 exponent, Bits[6:0] 0x73

0x0812 L HPM Gamma-0 linear, Bits[7:0] 0x24

0x0813 L HPM Gamma-0 linear, Bits[15:8] 0xD8

0x0814 L Reserved HPM Gamma-1 exponent, Bits[6:0] 0x59

0x0815 L HPM Delta-0 linear, Bits[7:0] 0xD2

0x0816 L HPM Delta-0 linear, Bits[15:8] 0x8D

0x0817 L Reserved HPM Delta-1 exponent, Bits[6:0] 0x5A

Global Demapping Control

0x0900 L Demap

control

IO_UPDATE

Reserved Demap

control IO_

UPDATE

0x00

0x0901 DPLL_0 DPLL_0 sampled address, Bits[7:0] 0x00

0x0902 DPLL_0 sampled address, Bits[15:8] 0x00

0x0903 DPLL_1 DPLL_1 sampled address, Bits[7:0] 0x00

0x0904 DPLL_1 sampled address, Bits[15:8] 0x00

0x0905 DPLL_2 DPLL_2 sampled address, Bits[7:0] 0x00

0x0906 DPLL_2 sampled address, Bits[15:8] 0x00

0x0907 DPLL_3 DPLL_3 sampled address, Bits[7:0] 0x00

0x0908 DPLL_3 sampled address, Bits[15:8] 0x00

0x0909 Demap

control

IO_UPDATE

Reserved Demap

control IO_

UPDATE

0x00

Common Operational Controls

AD9554-1 Data Sheet

Rev. C | Page 60 of 99

Reg.

Addr.

(Hex) Option Name D7 D6 D5 D4 D3 D2 D1 D0

Def

(Hex)

0x0A00 Global Reserved Soft sync all Calibrate

SYSCLK

Calibrate

all

Power-

down all

0x00

0x0A01 Reference

inputs

Reserved REFD

power-

down

REFC

power-

down

REFB

power-

down

REFA

power-

down

0x00

0x0A02 A Reserved REFD

timeout

REFC

timeout

REFB

timeout

REFA

timeout

0x00

0x0A03 Reserved REFD fault REFC fault REFB fault REFA fault 0x00

0x0A04 Reserved REFD

monitor

bypass

REFC

monitor

bypass

REFB

monitor

bypass

REFA

monitor

bypass

0x00

0x0A05 A Clear IRQ

groups

Clear

watchdog

timer

Reserved Clear

DPLL_3

IRQs

Clear

DPLL_2

IRQs

Clear

DPLL_1

IRQs

Clear

DPLL_0

IRQs

Clear

common

IRQs

Clear all

IRQs

0x00

0x0A06 A Clear

common

IRQ

SYSCLK

unlocked

SYSCLK

stable

SYSCLK

locked

SYSCLK cal

ended

SYSCLK cal

started

Watchdog

timer

Reserved 0x00

0x0A07 A Reserved REFB

validated

REFB fault

cleared

REFB fault Reserved REFA

validated

REFA fault

cleared

REFA fault 0x00

0x0A08 A Reserved REFD

validated

REFD fault

cleared

REFD fault Reserved REFC

validated

REFC fault

cleared

REFC fault 0x00

0x0A09 A Clear

DPLL_0 IRQ

Frequency

unclamped

Frequency

clamped

Phase slew

unlimited

Phase slew

limited

Frequency

unlocked

Frequency

locked

Phase

unlocked

Phase

locked

0x00

0x0A0A A DPLL_0

switching

DPLL_0 free

run

DPLL_0

holdover

History

updated

REFD

activated

REFC

activated

REFB

activated

REFA

activated

0x00

0x0A0B A Phase step

detected

Demap

control

unclamped

Demap

control

clamped

Clock

dist sync’d

APLL_0

unlocked

APLL_0

locked

APLL_0 cal

ended

APLL_0 cal

started

0x00

0x0A0C A Clear

DPLL_1 IRQ

Frequency

unclamped

Frequency

clamped

Phase slew

unlimited

Phase slew

limited

Frequency

unlocked

Frequency

locked

Phase

unlocked

Phase

locked

0x00

0x0A0D A DPLL_1

switching

DPLL_1

free run

DPLL_1

holdover

History

updated

REFD

activated

REFC

activated

REFB

activated

REFA

activated

0x00

0x0A0E A Phase step

detected

Demap

control

unclamped

Demap

control

clamped

Clock dist

sync’d

APLL_1

unlocked

APLL_1

locked

APLL_1 cal

ended

APLL_1 cal

started

0x00

0x0A0F A Clear

DPLL_2 IRQ

Frequency

unclamped

Frequency

clamped

Phase slew

unlimited

Phase slew

limited

Frequency

unlocked

Frequency

locked

Phase

unlocked

Phase

locked

0x00

0x0A10 A DPLL_2

switching

DPLL_2 free

run

DPLL_2

holdover

History

updated

REFD

activated

REFC

activated

REFB

activated

REFA

activated

0x00

0x0A11 A Phase step

detected

Demap

control

unclamped

Demap

control

clamped

Clock dist

sync’d

APLL_2

unlocked

APLL_2

locked

APLL_2 cal

ended

APLL_2 cal

started

0x00

0x0A12 A Clear

DPLL_3 IRQ

Frequency

unclamped

Frequency

clamped

Phase slew

unlimited

Phase slew

limited

Frequency

unlocked

Frequency

locked

Phase

unlocked

Phase

locked

0x00

0x0A13 A DPLL_3

switching

DPLL_3

free run

DPLL_3

holdover

History

updated

REFD

activated

REFC

activated

REFB

activated

REFA

activated

0x00

0x0A14 A Phase step

detected

Demap

control

unclamped

Demap

control

clamped

Clock dist

sync’d

APLL_3

unlocked

APLL_3

locked

APLL_3 cal

ended

APLL_3 cal

started

0x00

PLL_0 Operational Controls

0x0A20 PLL_0 sync

cal

Reserved APLL_0 soft

sync

APLL_0

calibrate

(not self-

clearing)

PLL_0

power-

down

0x00

0x0A21 PLL_0

output

Reserved OUT0B

disable

Reserved OUT0B

power-

down

Reserved 0x00

0x0A22 PLL_0 user

mode

Reserved DPLL_0 manual reference DPLL_0 switching mode DPLL_0

user

holdover

DPLL_0

user free

run

0x00

0x0A23 A PLL_0 reset Reserved Reset

DPLL_0

loop filter

Reset

DPLL_0

TW history

Reset

DPLL_0

autosync

0x00

0x0A24 A PLL_0

phase

Reserved DPLL_0

reset phase

offset

DPLL_0

decrement

phase

offset

DPLL_0

increment

phase

offset

0x00

PLL_1 Operational Controls

Data Sheet AD9554-1

Rev. C | Page 61 of 99

Reg.

Addr.

(Hex) Option Name D7 D6 D5 D4 D3 D2 D1 D0

Def

(Hex)

0x0A40

0x0A44

These registers mimic the PLL_0 operational controls registers (0x0A20 through 0x0A24) but the register addresses are

offset by 0x0020. All default values are identical.

PLL_2 Operational Controls

0x0A60

0x0A64

These registers mimic the PLL_0 operational controls registers (0x0A20 through 0x0A24) but the register addresses are

offset by 0x0040. All default values are identical.

PLL_3 Operational Controls

0x0A80

0x0A84

These registers mimic the PLL_0 operational controls registers (0x0A20 through 0x0A24) but the register addresses are

offset by 0x0060. All default values are identical.

Voltage Regulator

0x0B00 L Voltage

regulator

VREG, Bits[7:0] 0x00

0x0B01 L Reserved VREG, Bits[9:8] 0x00

Read Only Status Common Blocks (To show the latest status, Register 0x0D02 to Register 0x0D05 require an IO_UPDATE before being read)

0x0D00 R, L Reserved Reserved N/A

0x0D01 R, L SYSCLK and

PLL status

PLL_3

all locked

PLL_2

all locked

PLL_1

all locked

PLL_0

all locked

Reserved SYSCLK

calibration

busy

SYSCLK

stable

SYSCLK

lock detect

N/A

0x0D02 R Reference

status

DPLL_3

REFA active

DPLL_2

REFA active

DPLL_1

REFA active

DPLL_0

REFA active

REFA valid REFA fault REFA fast REFA slow N/A

0x0D03 R DPLL_3

REFB active

DPLL_2 REFB

active

DPLL_1

REFB active

DPLL_0

REFB active

REFB valid REFB fault REFB fast REFB slow N/A

0x0D04 R DPLL_3

REFC active

DPLL_2

REFC active

DPLL_1

REFC active

DPLL_0

REFC active

REFC valid REFC fault REFC fast REFC slow N/A

0x0D05 R DPLL_3

REFD active

DPLL_2

REFD active

DPLL_1

REFD active

DPLL_0

REFD active

REFD valid REFD fault REFD fast REFD slow N/A

0x0D06 R Reserved N/A

0x0D07 R Reserved N/A

IRQ Monitor

0x0D08 R, L IRQ,

common

SYSCLK

unlocked

SYSCLK

stable

SYSCLK

locked

SYSCLK cal

ended

SYSCLK cal

started

Watchdog

timer

Reserved N/A

0x0D09 R, L Reserved REFB

validated

REFB fault

cleared

REFB fault Reserved REFA

validated

REFA fault

cleared

REFA fault N/A

0x0D0A R, L Reserved REFD

validated

REFD fault

cleared

REFD fault Reserved REFC

validated

REFC fault

cleared

REFC fault N/A

0x0D0B R, L IRQ, DPLL_0 Frequency

unclamped

Frequency

clamped

Phase slew

unlimited

Phase slew

limited

Frequency

unlocked

Frequency

locked

Phase

unlocked

Phase

locked

N/A

0x0D0C R, L DPLL_0

switching

DPLL_0 free

run

DPLL_0

holdover

DPLL_0

history

updated

REFD

activated

REFC

activated

REFB

activated

REFA

activated

N/A

0x0D0D R, L Phase step

direction

Demap

control

unclamped

Demap

control

clamped

Clock dist

sync’d

APLL_0

unlocked

APLL_0

locked

APLL_0

cal ended

APLL_0

cal started

N/A

0x0D0E R, L IRQ, DPLL_1 Frequency

unclamped

Frequency

clamped

Phase slew

unlimited

Phase slew

limited

Frequency

unlocked

Frequency

locked

Phase

unlocked

Phase

locked

N/A

0x0D0F R, L DPLL_1

switching

DPLL_1 free

run

DPLL_1

holdover

DPLL_1

history

updated

REFD

activated

REFC

activated

REFB

activated

REFA

activated

N/A

0x0D10 R, L Phase step

direction

Demap

control

unclamped

Demap

control

clamped

Clock dist

sync’d

APLL_1

unlocked

APLL_1

locked

APLL_1 cal

ended

APLL_1 cal

started

N/A

AD9554-1 Data Sheet

Rev. C | Page 62 of 99

Reg.

Addr.

(Hex) Option Name D7 D6 D5 D4 D3 D2 D1 D0

Def

(Hex)

0x0D11 R, L IRQ, DPLL_2 Frequency

unclamped

Frequency

clamped

Phase slew

unlimited

Phase slew

limited

Frequency

unlocked

Frequency

locked

Phase

unlocked

Phase

locked

N/A

0x0D12 R, L DPLL_2

switching

DPLL_2 free

run

DPLL_2

holdover

DPLL_2

history

updated

REFD

activated

REFC

activated

REFB

activated

REFA

activated

N/A

0x0D13 R, L Phase step

direction

Demap

control

unclamped

Demap

control

clamped

Clock dist

sync’d

APLL_2

unlocked

APLL_2

locked

APLL_2 cal

ended

APLL_2 cal

started

N/A

0x0D14 R, L IRQ, DPLL_3 Frequency

unclamped

Frequency

clamped

Phase slew

unlimited

Phase slew

limited

Frequency

unlocked

Frequency

locked

Phase

unlocked

Phase

locked

N/A

0x0D15 R, L DPLL_3

switching

DPLL_3 free

run

DPLL_3

holdover

DPLL_3

history

updated

REFD

activated

REFC

activated

REFB

activated

REFA

activated

N/A

0x0D16 R, L Phase step

direction

Demap

control

unclamped

Demap

control

clamped

Clock dist

sync’d

APLL_3

unlocked

APLL_3

locked

APLL_3 cal

ended

APLL_3 cal

started

N/A

PLL_0 Read Only Status (To show the latest status, these registers require an IO_UPDATE before being read)

0x0D20 R, L PLL_0 lock

status

Reserved APLL_0 cal

in progress

APLL_0 freq

lock

DPLL_0 freq

lock

DPLL_0

phase lock

PLL_0 all

locked

N/A

0x0D21 R DPLL_0

loop state

Reserved DPLL_0 active ref DPLL_0

switching

DPLL_0

holdover

DPLL_0

free run

N/A

0x0D22 R Reserved Demap

controller

clamped

DPLL_0

phase slew

limited

DPLL_0

frequency

clamped

DPLL_0

history

available

N/A

0x0D23 R DPLL_0

holdover

history

DPLL_0 tuning word readback, Bits[7:0] N/A

0x0D24 R DPLL_0 tuning word readback, Bits[15:8] N/A

0x0D25 R DPLL_0 tuning word readback, Bits[23:16] N/A

0x0D26 R Reserved DPLL_0 tuning word readback, Bits[29:24] N/A

0x0D27 R DPLL_0

phase lock

detect

bucket

DPLL_0 phase lock detect bucket level, Bits[7:0] N/A

0x0D28 R Reserved DPLL_0 phase lock detect bucket level, Bits[11:8] N/A

0x0D29 R DPLL_0

frequency

lock detect

bucket

DPLL_0 frequency lock detect bucket level, Bits[7:0] N/A

0x0D2A R Reserved DPLL_0 frequency lock detect bucket level, Bits[11:8] N/A

PLL_1 Read Only Status (To show the latest status, these registers require an IO_UPDATE before being read)

0x0D40

0x0D4A

These registers mimic the PLL_0 read only status registers (0x0D20 through 0x0D2A) but the register addresses are offset

by 0x0020. All default values are identical.

N/A

PLL_2 Read Only Status (To show the latest status, these registers require an IO_UPDATE before being read)

0x0D60

0x0D6A

These registers mimic the PLL_0 read only status registers (0x0D20 through 0x0D2A) but the register addresses are offset

by 0x0040. All default values are identical.

N/A

PLL_3 Read Only Status (To show the latest status, these registers require an IO_UPDATE before being read)

0x0D80

0x0D8A

These registers mimic the PLL_0 read only status registers (0x0D20 through 0x0D2A) but the register addresses are offset

by 0x0060. All default values are identical.

N/A

VCAL Reference Control

0x0FFF VCAL

reference

access

VCAL reference access 0x00

0x1488 APLL_0 VCAL

reference

Reserved APLL_0 manual cal level,

Bits[1:0]

En APLL_0 man cal level 0x00

0x1588 APLL_1 VCAL

reference

Reserved APLL_1 manual cal level,

Bits[1:0]

En APLL_1 man cal level 0x00

0x1688 APLL_2 VCAL

reference

Reserved APLL_2 manual cal level,

Bits[1:0]

En APLL_2 Man Cal Level 0x00

0x1788 APLL_3 VCAL

reference

Reserved APLL_3 manual cal level,

Bits[1:0]

En APLL_3 man cal level 0x00

Data Sheet AD9554-1

Rev. C | Page 63 of 99

SERIAL CONTROL PORT CONFIGURATION (REGISTER 0x0000 TO REGISTER 0x0001)

Table 32. SPI Configuration A

Address Bits Bit Name Description

0x0000 7 Soft reset Device reset.

6 LSB first (SPI only) Bit order for SPI port. This bit has no effect in I²C mode.

1 = least significant bit first.

0 (default) = most significant bit first.

5 Address ascension (SPI only) This bit controls whether the register address is automatically incremented during a

multibyte transfer. This bit has no effect in I²C mode.

1 = Register addresses are automatically incremented in multibyte transfers.

0 (default) = Register addresses are automatically decremented in multibyte transfers.

4 Reserved Default: 0b.

[3:0] These bits are mirrors of Bits[7:4] of this register so that when the serial port is configured, the

pattern written is independent of an MSB first/LSB first setting interpretation. The

AD9554-1 internal logic performs a logical OR on the corresponding bits.

Bit 3 corresponds to Bit 4.

Bit 2 corresponds to Bit 5.

Bit 1 corresponds to Bit 6.

Bit 0 corresponds to Bit 7.

Table 33. SPI Configuration B

Address Bits Bit Name Description

0x0001 [7:6] Reserved Reserved.

5 Read buffer register For buffered registers, this bit controls whether the value read from the serial port is from the

actual (active) registers or the buffered copy.

1 = reads buffered values that take effect on the next assertion of IO_UPDATE.

0 (default) = reads values currently applied to the internal logic of the device.

[4:3] Reserved Reserved.

2 Reset sans regmap This bit resets the device while maintaining the current register settings.

1 = resets the device.

0 (default) = no action.

[1:0] Reserved Reserved.

CLOCK PART FAMILY ID (REGISTER 0x0003 TO REGISTER 0x0006)

Table 34. Clock Part Family ID

Address Bits Bit Name Description

0x0003 [7:4] Reserved Reserved.

[3:0] Chip type, Bits[3:0] The Analog Devices unified SPI protocol reserves this read only register location for

identifying the type of device. The default value of 0x05 identifies the AD9554-1 as a clock IC.

0x0004 [7:4] Clock part serial ID, Bits[3:0] The Analog Devices unified SPI protocol reserves this read only register location as the

lower four bits of the clock part serial ID that (along with Register 0x0005) uniquely

identifies the AD9554-1 within the Analog Devices clock chip family. No other Analog

Devices chip that adheres to the Analog Devices unified SPI will have these values for

[3:0] Reserved Default: 0xF.

0x0005 [7:0]

Clock part serial ID,

Bits[11:4]

The Analog Devices unified SPI protocol reserves this read only register location as the

upper eight bits of the clock part serial ID that (along with Register 0x0004) uniquely

identifies the AD9554-1 within the Analog Devices clock chip family. No other Analog

Devices chip that adheres to the Analog Devices unified SPI will have these values for

0x0006 [7:0] Part version, Bits[7:0] The Analog Devices unified SPI protocol reserves this read only register location for

identifying the die revision. Default: 0x05.

AD9554-1 Data Sheet

Rev. C | Page 64 of 99

SPI VERSION (REGISTER 0x000B)

Table 35. SPI Version

Address Bits Bit Name Description

0x000B [7:0] SPI version, Bits[7:0] The Analog Devices unified SPI protocol reserves this read only register location for identifying

the version of the unified SPI protocol. Default: 0x00.

VENDOR ID (REGISTER 0x000C TO REGISTER 0x000D)

Table 36. Vendor ID

Address Bits Bit Name Description

0x000C [7:0] Vendor ID, Bits[7:0] The Analog Devices unified SPI protocol reserves this read only register location for identifying

Analog Devices as the chip vendor of this device. All Analog Devices parts adhering to the

unified serial port specification have the same value in this register. Default: 0x56.

0x000D [7:0] Vendor ID, Bits[15:8] The Analog Devices unified SPI protocol reserves this read-only register location for identifying

Analog Devices as the chip vendor of this part. All Analog Devices parts adhering to the unified

serial port specification have the same value in this register. Default: 0x04.

IO_UPDATE (REGISTER 0x000F)

Table 37. IO_UPDATE

Address Bits Bit Name Description

0x000F [7:1] Reserved Reserved. Default: 0000000b

0 IO_UPDATE Writing a 1 to this bit transfers the data in the serial input/output buffer registers to the

internal control registers of the device. This is an autoclearing bit.

GENERAL CONFIGURATION (REGISTER 0x0100 TO REGISTER 0x010E)

Multifunction Pin Control (M0 to M3 and M5 to M7) and Watchdog Timer

Note that there is no M4 pin for this device.

Table 38. Multifunction Pins (M0 to M3 and M5 to M7) Control

Address Bits Bit Name Description

0x0100 [7:6] M3 driver mode, Bits[1:0] 00 (default) = active high CMOS.

01 = active low CMOS.

10 = open-drain PMOS (requires an external pull-down resistor).

11 = open-drain NMOS (requires an external pull-up resistor).

[5:4] M2 driver mode, Bits[1:0] The settings of these bits are identical to Register 0x0100, Bits[7:6].

[3:2] M1 driver mode, Bits[1:0] The settings of these bits are identical to Register 0x0100, Bits[7:6].

[1:0] M0 driver mode, Bits[1:0] The settings of these bits are identical to Register 0x0100, Bits[7:6].

0x0101 [7:6] M7 driver mode, Bits[1:0] The settings of these bits are identical to Register 0x0100, Bits[7:6].

[5:4] M6 driver mode, Bits[1:0] The settings of these bits are identical to Register 0x0100, Bits[7:6].

[3:2] M5 driver mode, Bits[1:0] The settings of these bits are identical to Register 0x0100, Bits[7:6].

[1:0] Reserved Default: 00b.

0x0102 [7:0] Reserved Default: 0x00.

0x0103 7 M0 output/input Input/output control for M0 pin.

0 (default) = input (control pin).

1 = output (status pin).

[6:0] M0 function, Bits[6:0] These bits control the function of the M0 pin. See Table 123 and Table 124 for details

about the input and output functions that are available. Default: 0x00 = high impedance

control pin, no function assigned.

0x0104 7 M1 output/input Input/output control for M1 pin (same as for the M0 pin, Register 0x0103, Bit 7).

[6:0] M1 function, Bits[6:0] These bits control the function of the M1 pin and are the same as Register 0x0103,

Bits[6:0]. Default: 0x00 = high impedance control pin, no function assigned.

Data Sheet AD9554-1

Rev. C | Page 65 of 99

Address Bits Bit Name Description

0x0105 7 M2 output/input Input/output control for M2 pin (same as for the M0 pin, Register 0x0103, Bit 7).

[6:0] M2 function, Bits[6:0] These bits control the function of the M2 pin and are the same as Register 0x0103,

Bits[6:0]. Default: 0x00 = high impedance control pin, no function assigned.

0x0106 7 M3 output/input Input/output control for M3 pin (same as for the M0 pin, Register 0x0103, Bit 7).

[6:0] M3 function, Bits[6:0] These bits control the function of the M3 pin and are the same as Register 0x0103,

Bits[6:0]. Default: 0x00 = high impedance control pin, no function assigned.

0x0107 [7:0] Reserved Default: 0x00.

0x0108 7 M5 output/input Input/output control for M5 pin (same as for the M0 pin, Register 0x0103, Bit 7).

[6:0] M5 function, Bits[6:0] These bits control the function of the M5 pin and are the same as Register 0x0103,

Bits[6:0]. Default: 0x00 = high impedance control pin, no function assigned.

0x0109 7 M6 output/input Input/output control for M6 pin (same as for the M0 pin, Register 0x0103, Bit 7).

[6:0] M6 function, Bits[6:0] These bits control the function of the M6 pin and are the same as Register 0x0103,

Bits[6:0]. Default: 0x00 = high impedance control pin, no function assigned.

0x010A 7 M7 output/input Input/output control for M7 pin (same as for the M0 pin, Register 0x0103, Bit 7).

[6:0] M7 function, Bits[6:0] These bits control the function of the M7 pin and are the same as Register 0x0103,

Bits[6:0]. Default: 0x00 = high impedance control pin, no function assigned.

0x010B [7:0] Reserved Default: 0x00.

0x010C [7:0] Reserved Default: 0x00.

0x010D [7:0] Watchdog timer Watchdog timer, Bits[7:0]. The watchdog timer stops when this register is written and

restarts on the next IO_UPDATE (Register 0x000F = 0x01).

Default: 0x00 (0x0000 = disabled). The units are in milliseconds.

0x010E [7:0] Watchdog timer, Bits[15:8]. The watchdog timer stops when this register is written and

restarts on the next IO_UPDATE (Register 0x000F = 0x01). Default: 0x00.

IRQ MASK (REGISTER 0x010F TO REGISTER 0x011F)

The IRQ mask register bits form a one-to-one correspondence with the bits of the IRQ monitor register (0x0D08 to 0x0D16). When set to

Logic 1, the IRQ mask bits enable the corresponding IRQ monitor bits to indicate an IRQ event. The default for all IRQ mask bits is

Logic 0, which prevents the IRQ monitor from detecting any internal interrupts.

Table 39. IRQ Mask for SYSCLK and Watchdog Timer

Address Bits Bit Name Description

0x010F 7 SYSCLK unlocked Enables IRQ to indicate that the system clock has gone from locked to unlocked.

6 SYSCLK stable Enables IRQ to indicate that the system clock has gone from unstable to stable.

5 SYSCLK locked Enables IRQ to indicate that the system clock has gone from unlocked to locked.

4 SYSCLK calibration ended Enables IRQ to indicate that the system clock calibration sequence has ended.

3 SYSCLK calibration started Enables IRQ to indicate that the system clock calibration sequence has started.

2 Watchdog timer Enables IRQ to indicate expiration of the watchdog timer.

[1:0] Reserved Default: 00b.

Table 40. IRQ Mask for Reference Inputs

Address Bits Bit Name Description

0x0110 7 Reserved Reserved.

6 REFB validated Enables IRQ to indicate that REFB has been validated.

5 REFB fault cleared Enables IRQ to indicate that REFB has been cleared of a previous fault.

4 REFB fault Enables IRQ to indicate that REFB has been faulted.

3 Reserved Reserved.

2 REFA validated Enables IRQ to indicate that REFA has been validated.

1 REFA fault cleared Enables IRQ to indicate that REFA has been cleared of a previous fault.

0 REFA fault Enables IRQ to indicate that REFA has been faulted.

AD9554-1 Data Sheet

Rev. C | Page 66 of 99

Address Bits Bit Name Description

0x0111 7 Reserved Reserved.

6 REFD validated Enables IRQ to indicate that REFD has been validated.

5 REFD fault cleared Enables IRQ to indicate that REFD has been cleared of a previous fault.

4 REFD fault Enables IRQ to indicate that REFD has been faulted.

3 Reserved Reserved.

2 REFC validated Enables IRQ to indicate that REFC has been validated.

1 REFC fault cleared Enables IRQ to indicate that REFC has been cleared of a previous fault.

0 REFC fault Enables IRQ to indicate that REFC has been faulted.

Table 41. IRQ Mask for the Digital PLL0 (DPLL_0)

Address Bits Bit Name Description

0x0112 7 Frequency unclamped Enables IRQ to indicate that DPLL_0 has exited a frequency clamped state.

6 Frequency clamped Enables IRQ to indicate that DPLL_0 has entered a frequency clamped state.

5 Phase slew unlimited Enables IRQ to indicate that DPLL_0 has exited a phase slew limited state.

4 Phase slew limited Enables IRQ to indicate that DPLL_0 has entered a phase slew limited state.

3 Frequency unlocked Enables IRQ to indicate that DPLL_0 has lost frequency lock.

2 Frequency locked Enables IRQ to indicate that DPLL_0 has acquired frequency lock.

1 Phase unlocked Enables IRQ to indicate that DPLL_0 has lost phase lock.

0 Phase locked Enables IRQ to indicate that DPLL_0 has acquired phase lock.

0x0113 7 Switching Enables IRQ to indicate that DPLL_0 is switching to a new reference.

6 Free run Enables IRQ to indicate that DPLL_0 has entered free run mode.

5 Holdover Enables IRQ to indicate that DPLL_0 has entered holdover mode.

4 History updated Enables IRQ to indicate that DPLL_0 has updated its tuning word history.

3 REFD activated Enables IRQ to indicate that DPLL_0 has activated REFD.

2 REFC activated Enables IRQ to indicate that DPLL_0 has activated REFC.

1 REFB activated Enables IRQ to indicate that DPLL_0 has activated REFB.

0 REFA activated Enables IRQ to indicate that DPLL_0 has activated REFA.

0x0114 7 Phase step detection Enables IRQ to indicate that DPLL_0 has detected a large phase step at the reference

input.

6 Demap control unclamped

Enables IRQ to indicate that the DPLL_0 demapping controller tuning word has

become unclamped.

5 Demap control clamped

Enables IRQ to indicate that the DPLL_0 demapping controller tuning word has

become clamped.

4 Sync clock distribution Enables IRQ for indicating a distribution sync event.

3 APLL_0 unlocked Enables IRQ for APLL_0 unlocked.

2 APLL_0 locked Enables IRQ for APLL_0 locked.

1 APLL_0 calibration complete Enables IRQ for APLL_0 calibration complete.

0 APLL_0 calibration started Enables IRQ for APLL_0 calibration started.

Table 42. IRQ Mask for the Digital PLL1 (DPLL_1)

Address Bits Bit Name Description

0x0115 [7:0] See Table 41 IRQ mask for DPLL_1, same as IRQ mask for the digital PLL0 (DPLL_0) registers

(Register 0x0112 through Register 0x0114). All default values are identical.

0x0116 [7:0] See Table 41

0x0117 [7:0] See Table 41

Table 43. IRQ Mask for the Digital PLL2 (DPLL_2)

Address Bits Bit Name Description

0x0118 [7:0] See Table 41 IRQ mask for DPLL_2, same as IRQ mask for the digital PLL0 (DPLL_0) registers

(Register 0x0112 through Register 0x0114). All default values are identical.

0x0119 [7:0] See Table 41

0x011A [7:0] See Table 41

Data Sheet AD9554-1

Rev. C | Page 67 of 99

Table 44. IRQ Mask for the Digital PLL3 (DPLL_3)

Address Bits Bit Name Description

0x011B [7:0] See Table 41 IRQ mask for DPLL_3, same as IRQ mask for the digital PLL0 (DPLL_0) registers

(Register 0x0112 through Register 0x0114). All default values are identical.

0x011C [7:0] See Table 41

0x011D [7:0] See Table 41

Table 45. Pad Control for Mx Pins

Address Bits Bit Name Description

0x011E 7 M7 configuration M7 pin output drive strength.

0 (default) = high (approximately 6 mA) drive strength.

1 = low (approximately 3 mA) drive strength.

6 M6 configuration Same as Bit 7 of this register, except that it applies to the M6 pin.

5 M5 configuration Same as Bit 7 of this register, except that it applies to the M5 pin.

4 Reserved Default: 0b.

3 M3 configuration Same as Bit 7 of this register, except that it applies to the M3 pin.

2 M2 configuration Same as Bit 7 of this register, except that it applies to the M2 pin.

1 M1 configuration Same as Bit 7 of this register, except that it applies to the M1 pin.

0 M0 configuration Same as Bit 7 of this register, except that it applies to the M0 pin.

0x011F [7:3] Reserved Default: 00000b.

2 SPI configuration Same as Bit 7 of Register 0x011E, except that it applies to the SDIO pin.

[1:0] Reserved Default: 00b.

SYSTEM CLOCK (REGISTER 0x0200 TO REGISTER 0x0208)

Table 46. System Clock PLL Feedback Divider (K Divider) and Configuration

Address Bits Bit Name Description

0x0200 [7:0] System clock K divider, Bits[7:0] System clock PLL feedback divider value = 4 ≤ K ≤ 255. Default: 0x00.

Table 47. SYSCLK Configuration

Address Bits Bit Name Description

0x0201 [7:4] Reserved Reserved.

3 SYSCLK XTAL enable Enables the crystal maintaining amplifier for the system clock input.

1 (default) = crystal mode (crystal maintaining amplifier enabled).

0 = external crystal oscillator or other system clock source.

[2:1] SYSCLK J1 divider, Bits[1:0] System clock input divider.

00 (default): ÷1.

01: ÷2.

10: ÷4.

11: ÷8.

SYSCLK doubler enable

(J0 divider)

Enables the clock doubler on the system clock input to reduce noise. Setting this

bit may prevent the SYSCLK PLL from locking if the input duty cycle is not close

enough to 50%. See Table 4 for the limits on duty cycle.

0 (default) = disable.

1 = enable.

Table 48. System Clock Reference Frequency

Address Bits Bit Name Description

0x0202 [7:0] System clock reference frequency (Hz), Bits[23:0] System clock reference frequency, Bits[7:0]. Default: 0x00.

0x0203 [7:0] System clock reference frequency, Bits[15:8]. Default: 0x00.

0x0204 [7:0] System clock reference frequency, Bits[23:16]. Default: 0x00.

0x0205 [7:4] Reserved Default: 0x0.

[3:0] System clock reference frequency (Hz), Bits[27:24] System clock reference frequency, Bits[27:24]. Default: 0x0.

AD9554-1 Data Sheet

Rev. C | Page 68 of 99

Table 49. System Clock Stability Period

Address Bits Bit Name Description

0x0206 [7:0]

System clock stability period

(ms), Bits[15:0]

System clock period, Bits[7:0]. The system clock stability period is the amount of time

that the system clock PLL must be locked before it is declared stable. The system clock

stability period is reset automatically if the user writes to this register. The system clock

stability period restarts on the next IO_UPDATE (Register 0x000F = 0x01). Default: 0x32

(0x000032 = 50 ms).

0x0207 [7:0] System clock period, Bits[15:8]. The system clock stability period is reset automatically if

the user writes to this register. The system clock stability timer restarts on the next

IO_UPDATE (Register 0x000F = 0x01). Default: 0x00.

0x0208 [7:4] Reserved Default: 0x0.

[3:0]

System clock stability period

(ms), Bits[19:16]

System clock period, Bits[19:16]. The system clock stability period is reset automatically

if the user writes to this register. The system clock stability period restarts on the next

IO_UPDATE (Register 0x000F = 0x01). Default: 0x0. The units are in milliseconds.

REFERENCE INPUT A (REGISTER 0x0300 TO REGISTER 0x031E)

Table 50. REFA Logic Type

Address Bits Bit Name Description

0x0300 [7:2] Reserved Default: 000000b.

[1:0] REFA logic type, Bits[1:0] Selects logic family for REFA input receiver; only the REFA pin is used in CMOS mode.

00b (default) = 1.8 V or 1.5 V single-ended CMOS.

01b = ac-coupled differential.

10b = dc-coupled LVDS (fIN ≤ 10.24 MHz).

11b = unused.

Table 51. REFA R Divider (20 Bits) DPLL

Address Bits Bit Name Description

0x0301 [7:0] R divider, Bits[15:0] DPLL integer reference divider (minus 1), Bits[7:0]. Default: 0x00. (For example, 0x00000

equals an R divider of 1.)

0x0302 [7:0] DPLL integer reference divider (minus 1), Bits[15:8]. Default: 0x00.

0x0303 [7:4] Reserved Default: 0x0.

[3:0] R divider, Bits[19:16] DPLL integer reference divider (minus 1), Bits[19:16]. Default: 0x0.

Table 52. Nominal Period of REFA Input Clock

Address Bits Bit Name Description

0x0304 [7:0] REFA period (fs), Bits[39:0] Nominal reference period, Bits[7:0]. Default: 0x00.

0x0305 [7:0] Nominal reference period, Bits[15:8]. Default: 0x00.

0x0306 [7:0] Nominal reference period, Bits[23:16]. Default: 0x00.

0x0307 [7:0] Nominal reference period, Bits[31:24]. Default: 0x00.

0x0308 [7:0] Nominal reference period, Bits[39:32]. Default: 0x00.

Data Sheet AD9554-1

Rev. C | Page 69 of 99

Table 53. REFA Frequency Tolerance

Address Bits Bit Name Description

0x0309 [7:0]

Inner tolerance

(1/(ppm error)), Bits[15:0]

Input reference frequency monitor inner tolerance, Bits[7:0]. Default: 0x14.

0x030A [7:0] Input reference frequency monitor inner tolerance, Bits[15:8]. Default: 0x00.

0x030B [7:4] Reserved Default: 0x0.

[3:0]

Inner tolerance

(1/(ppm error)), Bits[19:16]

Input reference frequency monitor inner tolerance, Bits[19:16]. Default for

clock requires an inner tolerance of ±9.2 ppm and an outer tolerance of ±12 ppm. An

SMC clock requires an outer tolerance of ±48 ppm. The allowable range for the inner

tolerance is 0x00A (10%) to 0x8FF (2 ppm).

0x030C [7:0]

Outer tolerance

(1/(ppm error)), Bits[15:0]

Input reference frequency monitor outer tolerance, Bits[7:0]. Default: 0x0A.

0x030D [7:0] Input reference frequency monitor outer tolerance, Bits[15:8]. Default: 0x00.

0x030E [7:4] Reserved Default: 0x0.

[3:0]

Outer tolerance

(1/(ppm error)), Bits[19:16]

Input reference frequency monitor outer tolerance, Bits[19:16]. Default for Register 0x030C to

inner tolerance of ±9.2 ppm and an outer tolerance of ±12 ppm. An SMC clock requires

an outer tolerance of ±48 ppm. The outer tolerance must be greater than the inner

tolerance so that there is hysteresis.

Table 54. REFA Validation Timer

Address Bits Bit Name Description

0x030F [7:0]

Validation timer (ms),

Bits[15:0] (up to 65.5 sec)

Validation timer, Bits[7:0]. Default: 0x0A. This is the amount of time a reference input must

be unfaulted before it is declared valid by the reference input monitor. Default: 10 ms.

0x0310 [7:0] Validation timer, Bits[15:8]. Default: 0x00.

Table 55. REFA Phase/Frequency Lock Detectors

Address Bits Bit Name Description

0x0311 [7:0]

Phase lock threshold (ps),

Bits[23:0]

Phase lock threshold, Bits[7:0]. Default: 0xBC. Default of 0x0002BC for Register 0x0311

through Register 0x313 = 700 ps.

0x0312 [7:0] Phase lock threshold, Bits[15:8]. Default: 0x02.

0x0313 [7:0] Phase lock threshold, Bits[23:16]. Default: 0x00.

0x0314 [7:0] Phase lock fill rate, Bits[7:0] Phase lock fill rate, Bits[7:0]. Default: 0x0A = 10 code/PFD cycle.

0x0315 [7:0]

Phase lock drain rate,

Bits[7:0]

Phase lock drain rate, Bits[7:0]. Default: 0x0A = 10 code/PFD cycle.

0x0316 [7:0]

Frequency lock threshold

(ps), Bits[23:0]

Frequency lock threshold, Bits[7:0]. Default: 0xBC. Default of 0x0002BC for Register 0x0316

through Register 0x0318 = 700 ps.

0x0317 [7:0] Frequency lock threshold, Bits[15:8]. Default: 0x02.

0x0318 [7:0] Frequency lock threshold, Bits[23:16]. Default: 0x00.

0x0319 [7:0]

Frequency lock fill rate,

Bits[7:0]

Frequency lock fill rate, Bits[7:0]. Default: 0x0A = 10 code/PFD cycle.

0x031A [7:0]

Frequency lock drain rate,

Bits[7:0]

Frequency lock drain rate, Bits[7:0]. Default: 0x0A = 10 code/PFD cycle.

Table 56. REFA Phase Step Threshold

Address Bits Bit Name Description

0x031B [7:0]

Phase step threshold (ps),

Bits[23:0]

Phase step threshold, Bits[7:0]. Default: 0x00. Note that a phase step threshold of

0x000000 means that this feature is disabled.

0x031C [7:0] Phase step threshold, Bits[15:8]. Default: 0x00.

0x031D [7:0] Phase step threshold, Bits[23:16]. Default: 0x00.

0x031E [7:4] Reserved Default: 0x0.

[3:0]

Phase step threshold (ps),

Bits[27:24]

Phase step threshold, Bits[27:24].

AD9554-1 Data Sheet

Rev. C | Page 70 of 99

REFERENCE INPUT B (REGISTER 0x0320 TO REGISTER 0x033E)

These registers mimic the Reference Input A registers (Register 0x0300 through Register 0x031E) but the register addresses are offset by

0x0020. All default values are identical.

REFERENCE INPUT C (REGISTER 0x0340 TO REGISTER 0x035E)

These registers mimic the Reference Input A registers (Register 0x0300 through Register 0x031E) but the register addresses are offset by

0x0040. All default values are identical.

REFERENCE INPUT D (REGISTER 0x0360 TO REGISTER 0x037E)

These registers mimic the Reference Input A registers (Register 0x0300 through Register 0x031E) but the register addresses are offset by

0x0060. All default values are identical.

DPLL_0 CONTROLS (REGISTER 0x0400 TO REGISTER 0x041E)

Table 57. DPLL_0 Free Run Frequency Tuning Word

Address Bits Bit Name Description

0x0400 [7:0]

30-bit free running frequency tuning word

Bits[23:0]

Free running frequency tuning word, Bits[7:0]. Default: 0x00.

0x0401 [7:0] Free running frequency tuning word, Bits[15:8]. Default: 0x00.

0x0402 [7:0] Free running frequency tuning word, Bits[23:16]. Default: 0x00.

0x0403 [7:6] Reserved Default: 00b.

[5:0]

30-bit free running frequency tuning word

Bits[29:24]

Free running frequency tuning word, Bits[29:24]. Default: 0x00.

Table 58. DPLL_0 DCO Integer

Address Bits Bit Name Description

0x0404 [7:4] Reserved This register is used internally. It is usually 0x1 but may differ depending on how the device is configured.

When writing to this register, read the current value and write the same value back to this register.

[3:0]

DCO integer,

Bits[3:0]

This register contains the integer part of the DCO frequency divider. Valid values are 0x7 to 0xD, and the

AD9554-1 evaluation software frequency planning wizard can help determine the optimal value.

Default: 0x7.

Table 59. DPLL_0 Frequency Clamp

Address Bits Bit Name Description

0x0405 [7:0]

Lower limit of pull-in range,

Bits[15:0]

Lower limit pull-in range, Bits[7:0]. The value in these registers is the 20 most significant

bits of the lowest allowable tuning word used by the DPLL. Default: 0xCC.

0x0406 [7:0] Lower limit pull-in range, Bits[15:8]. Default: 0xCC.

0x0407 [7:4] Reserved Default: 0x0.

[3:0]

Lower limit of pull-in range,

Bits[19:16]

Lower limit pull-in range, Bits[19:16]. Default: 0x0.

0x0408 [7:0]

Upper limit of pull-in range,

Bits[15:0]

Upper limit pull-in range, Bits[7:0]. Default: 0x33.

0x0409 [7:0] Upper limit pull-in range, Bits[15:8]. Default: 0x33.

0x040A [7:4] Reserved Default: 0x0.

[3:0]

Upper limit of pull-in range,

Bits[19:16]

Upper limit pull-in range, Bits[19:16]. Default: 0xF.

Table 60. DPLL_0 Holdover History

Address Bits Bit Name Description

0x040B [7:0]

DPLL_0 history

accumulation timer (ms),

Bits[15:0]

History accumulation timer, Bits[7:0]. Default: 0x0A. For Register 0x040B and

tuning word averaging used to determine the tuning word used in holdover. Behavior is

undefined for a timer value of 0. Default value: 0x000A = 10 ms.

0x040C [7:0] History accumulation timer, Bits[15:8]. Default: 0x00.

Data Sheet AD9554-1

Rev. C | Page 71 of 99

Table 61. DPLL_0 History Mode

Address Bits Bit Name Description

0x040D [7:5] Reserved Reserved.

4 Single sample fallback Controls holdover history. If tuning word history is not available for the reference that was

active just prior to holdover, then the following:

0 (default) = uses the free running frequency tuning word register value.

1 = uses the last tuning word from the DPLL.

3 Persistent history Controls holdover history initialization. When switching to a new reference:

0 (default) = clears the tuning word history.

1 = retains the previous tuning word history.

[2:0]

Incremental average,

Bits[2:0]

History mode value from 0 to 7. Default: 0. When set to nonzero, causes the first history

accumulation to update prior to the first complete averaging period. After the first full

interval, updates occur only at the full period.

0 (default) = update only after the full interval has elapsed.

1 = update at 1/2 the full interval.

2 = update at 1/4 and 1/2 of the full interval.

3 = update at 1/8, 1/4, and 1/2 of the full interval.

…

7 = update at 1/256, 1/128, 1/64, 1/32, 1/16, 1/8, 1/4, and 1/2 of the full interval.

Table 62. DPLL_0 Fixed Closed Loop Phase Offset

Address Bits Bit Name Description

0x040E [7:0] Fixed phase offset (signed; ps) Fixed phase offset, Bits[7:0]. Default: 0x00.

0x040F [7:0] Fixed phase offset, Bits[15:8]. Default 0x00.

0x0410 [7:0] Fixed phase offset, Bits[23:16]. Default: 0x00.

0x0411 [7:6] Reserved Reserved; default: 0x0.

[5:0] Fixed phase offset (signed; ps) Fixed phase offset, Bits[29:24]. Default: 0x00.

Table 63. DPLL_0 Incremental Closed-Loop Phase Offset Step Size

Address Bits Bit Name Description

0x0412 [7:0]

Incremental phase offset

step size (ps), Bits[15:0]

Incremental phase offset step size, Bits[7:0]. Default: 0x00. This register controls the static

phase offset step size of the DPLL while it is locked. See Register 0x0A24 for the bits that

increment, decrement, and reset the phase offset.

0x0413 [7:0]

Incremental phase offset step size, Bits[15:8]. Default: 0x00. This register controls the static

phase offset step size of the DPLL while it is locked.

Table 64. DPLL_0 Phase Slew Rate Limit

Address Bits Bit Name Description

0x0414 [7:0]

Phase slew rate limit

(μs/sec), Bits[15:0]

Phase slew rate limit, Bits[7:0]. Default: 0x00. This register controls the maximum allowable

phase slewing during phase adjustment. (The phase adjustment controls are in Register

0x040E to Register 0x0411.) Default phase slew rate limit: 0, or disabled. Minimum useful value

is 100 μs/sec.

0x0415 [7:0] Phase slew rate limit, Bits[15:8]. Default = 0x00.

AD9554-1 Data Sheet

Rev. C | Page 72 of 99

Table 65. DPLL_0 Demapping Control

Address Bits Bit Name Description

0x0416 [7:1] Reserved Reserved, Bits[7:1] (default: 0x00)

0 Enable demap controller Enables the demapping controller.

0 (default) = The demapping controller is disabled.

1 = The demapping controller is enabled.

0x0417 [7:0] Sampled address, Bits[15:0] Sampled address, Bits[7:0]. Default: 0x00.

0x0418 [7:0] Sampled address, Bits[15:8]. Default: 0x00.

0x0419 [7:0] Set point address, Bits[15:0] Set point address, Bits[7:0]. Default: 0x00.

0x041A [7:0] Set point address, Bits[15:8]. Default: 0x00.

0x041B [7:0] Gain, Bits[23:0] Gain, Bits[7:0]. Default: 0x00.

0x041C [7:0] Gain, Bits[15:8]. Default: 0x00.

0x041D [7:0] Gain, Bits[23:16]. Default: 0x00.

0x041E [7:0] Clamp value, Bits[7:0] Clamp value, Bits[7:0]. Default: 0x00.

APLL_0 CONFIGURATION (REGISTER 0x0430 TO REGISTER 0x0434)

Table 66. Output PLL_0 (APLL_0) Setting1

Address Bits Bit Name Description

0x0430 7 Reserved Default: 0b.

[6:0]

Output PLL0 (APLL_0)

charge pump

current, Bits[6:0]

LSB: 3.5 μA. 0000001b = 1 × LSB; 0000010b = 2 × LSB; 1111111b = 127 × LSB.

Default: 0x2E = 451 μA CP current.

0x0431 [7:0]

Output PLL0 (APLL_0)

feedback M0

divider, Bits[7:0]

Division: 14 to 255. Default: 0x00.

0x0432 [7:6]

APLL_0 loop filter control,

Bits[7:0]

Second pole resistor (RP2). Default: 0x7F.

RP2 (Ω) Bit 7 Bit 6

500 0 0

333 (default) 0 1

250 1 0

200 1 1

[5:3] Zero resistor (RZERO).

RZERO (Ω) Bit 5 Bit 4 Bit 3

1500 0 0 0

1250 0 0 1

1000 0 1 0

930 0 1 1

1250 1 0 0

1000 1 0 1

750 1 1 0

680 (default) 1 1 1

[2:0] First pole capacitor (CP1).

CP1 (pF) Bit 2 Bit 1 Bit 0

10 0 0 0

30 0 0 1

40 0 1 0

70 0 1 1

90 1 0 0

110 1 0 1

130 1 1 0

150 (default) 1 1 1

Data Sheet AD9554-1

Rev. C | Page 73 of 99

Address Bits Bit Name Description

0x0433 [7:2] Reserved Default: 0x00.

1 P0 divider reset 0 (default) = normal operation for the P0 divider.

1 = P0 divider held in reset.

0 APLL_0 loop filter control,

Bit 8

Bypass internal RZERO.

0 (default) = use the internal RZERO resistor.

1 = bypass the internal RZERO resistor (makes RZERO = 0 Ω and requires the use

of an external zero resistor in addition to the capacitor to ground on the LF_0 pin).

1 Note that the default APLL loop bandwidth is 240 kHz.

OUTPUT PLL_0 (APLL_0) SYNC AND CLOCK DISTRIBUTION (REGISTER 0x0434 TO REGISTER 0x043E)

Table 67. P0 Divider Settings1

Address Bits Bit Name Description

0x0434 [7:4] Reserved Default: 0x0.

[3:0] P0 divider divide ratio, Bits[3:0] 0000b (default)/0001b: undefined.

0010b: ÷2. This setting is permitted only if the APLL VCO frequency is ≤2500 MHz.

0011b: ÷3.

0101b: ÷5.

0110b: ÷6.

0111b: ÷7.

1000b: ÷8.

1001b: ÷9.

1010b: ÷10.

1011b: ÷11.

1 If the user changes this register after APLL calibration, the user must either issue another APLL calibration (see Figure 27), or issue a P divider reset for that PLL. For

example, if the user reconfigures the P0 divider after APLL_0 calibration, the user must reset the P0 divider using Bit 1 in Register 0x0433.

Table 68. Distribution Output Synchronization Settings (OUT0)

Address Bits Bit Name Description

0x0435 [7:3] Reserved Default: 0x00.

2 Sync source selection Selects the sync source for the clock distribution output channels.

0 (default) = direct. The sync pulse is gated only by APLL calibration and lock.

1 = active reference. This mode is similar to direct mode except that the sync pulse

occurs on the next edge of the actively selected reference.

[1:0] Automatic sync mode, Bits[1:0] Auto sync mode.

00 = (default) disabled.

01 = sync on DPLL frequency lock.

10 = sync on DPLL phase lock.

11 = reserved.

0x0436 [7:3] Reserved Reserved.

2 APLL_0 mask sync 0 (default) = the clock distribution SYNC function is delayed until the APLL has been

calibrated and is locked. After APLL calibration and lock, the output clock distribution

sync is armed, and the SYNC function for the clock outputs is under the control of

1 = overrides the lock detector state of the APLL; allows Register 0x0435 to control the

output SYNC function, regardless of the APLL lock status.

1 Mask OUT0B sync Masks the synchronous reset to the OUT0B divider.

0 (default) = unmasked.

1 = masked. Setting this bit asynchronously releases the OUT0B divider from static sync

state, thus allowing the OUT0B divider to toggle. OUT0B ignores all sync events while

this bit is set. Setting this bit does not enable the output drivers connected to this

channel.

0 Reserved Default: 0b.

AD9554-1 Data Sheet

Rev. C | Page 74 of 99

Table 69. Distribution OUT0B Settings

Address Bits Bit Name Description

0x043B [7:3] Reserved Reserved. Default: 0x00

[2:1] OUT0B mode Selects the operating mode of OUT0B.

00 (default) = 14 mA (used for ac-coupled LVDS and dc-coupled HCSL).

01 = 21 mA (intended as an intermediate amplitude setting).

10 = 28 mA (used for ac-coupled LVPECL-compatible amplitudes with 100 Ω termination).

Note that damage to the output drivers can result if 28 mA mode is used without external termination

resistors (either to ground or across the differential pair).

11 = power down and tristate outputs.

0 Invert polarity Controls the OUT0B polarity.

0 (default) = normal polarity.

1 = inverted polarity.

Table 70. Q0_B Divider Setting

Address Bits Bit Name Description

0x043C [7:0] Q0_B divider, Bits[7:0] 10-bit channel divider, Bits[7:0] (LSB). Default: 0x00.

Division equals channel divider, Bits[9:0] + 1.

[9:0] = 0 is divide-by-1.

[9:0] = 1 is divide-by-2.

…

[9:0] = 1023 is divide-by-1024.

0x043D [7:2] Reserved Default: 0x00.

[1:0] Q0_B divider, Bits[9:8] 10-bit channel divider, Bits[9:8] (MSB).

0x043E [7:6] Reserved Default: 0x0.

[5:0]

Q0_B divider phase,

Bits[5:0]

Divider initial phase after sync relative to the divider input clock (from the P0 divider output).

LSB is ½ of a period of the divider input clock. Default: 0x0.

Phase = 0 is no phase offset.

Phase = 1 is ½ a period offset.

DPLL_0 SETTINGS FOR REFERENCE INPUT A (REFA) (REGISTER 0x0440 TO REGISTER 0x044C)

Table 71. DPLL_0 REFA Priority Setting

Address Bits Bit Name Description

0x0440 [7:3] Reserved Default: 00000b.

[2:1] REFA priority These bits set the priority level (0 to 3) of REFA relative to the other input references.

00 (default) = 0 (highest).

01 = 1.

10 = 2.

11 = 3.

0 Enable REFA This bit enables DPLL_0 to lock to REFA.

0 (default) = REFA is not enabled for use by DPLL_0.

1 = REFA is enabled for use by DPLL_0.

Data Sheet AD9554-1

Rev. C | Page 75 of 99

Table 72. DPLL_0 REFA Loop Bandwidth Scaling Factor

Address Bits Bit Name Description

0x0441 [7:0]

Digital PLL_0 loop

bandwidth scaling

factor, Bits[15:0]

(unit of 0.1 Hz)

Digital PLL loop bandwidth scaling factor, Bits[7:0]. Default: 0x0.

0x0442 [7:0] Digital PLL loop bandwidth scaling factor, Bits[15:8]. Default: 0x00. The default for

the DPLL phase detector frequency divided by 50. The DPLL may not lock reliably if the DPLL

loop bandwidth is <50 Hz and a crystal is used for the system clock. See the Choosing the

SYSCLK Source section for details.

0x0443 [7:2] Reserved Default: 0x00.

Base loop filter

selection

0 = base loop filter with normal (70°) phase margin (default).

1 = base loop filter with high phase margin. (For loop bandwidth ≤2 kHz, there is ≤0.1 dB

peaking in the closed-loop transfer function. Setting this bit is also recommended for loop

bandwidths >2 kHz.)

Digital PLL_0 loop

bandwidth scaling

factor, Bit 16 (unit of

0.1 Hz)

Digital PLL loop bandwidth scaling factor, Bit 16. Default: 0x0.

Table 73. DPLL_0 REFA Integer Part of Feedback (N0) Divider

Address Bits Bit Name Description

0x0444 [7:0] Digital PLL_0 feedback divider—Integer Part N0 DPLL integer feedback divider (minus 1), Bits[7:0]. Default: 0x00.

(For example, an N0 divider value of one is achieved by writing

0x000000 to Register 0x0444 to Register 0x0446.)

0x0445 [7:0] DPLL integer feedback divider, Bits[15:8]. Default: 0x00.

0x0446 [7:2] Reserved Default: 0x00.

[1:0] Digital PLL_0 feedback divider—Integer Part N0 DPLL integer feedback divider, Bits[17:16]. Default: 0b.

Default for Register 0x0444 to Register 0x0446: 0x000000.

Table 74. DPLL_0 REFA Fractional Part of Fractional Feedback Divider—FRAC0

Address Bits Bit Name Description

0x0447 [7:0]

Digital PLL_0

fractional feedback

divider—FRAC0,

Bits[23:0]

The numerator of the fractional-N feedback divider, Bits[7:0]. Default: 0x00.

0x0448 [7:0] The numerator of the fractional-N feedback divider, Bits[15:8]. Default: 0x00.

0x0449 [7:0] The numerator of the fractional-N feedback divider, Bits[23:16]. Default: 0x00.

Table 75. DPLL_0 REFA Modulus of Fractional Feedback Divider—MOD0

Address Bits Bit Name Description

0x044A [7:0]

Digital PLL_0 feedback

divider modulus—MOD0,

The denominator of the fractional-N feedback divider, Bits[7:0]. Default: 0x00.

Setting MOD0 to 0x000000 disables and bypasses the fractional divider.

0x044B [7:0] Bits[23:0] The denominator of the fractional-N feedback divider, Bits[15:8]. Default: 0x00.

0x044C [7:0] The denominator of the fractional-N feedback divider, Bits[23:16]. Default: 0x00.

DPLL_0 SETTINGS FOR REFERENCE INPUT B (REFB) (REGISTER 0x044D TO REGISTER 0x0459)

Table 76. DPLL_0 REFB Priority Setting

Address Bits Bit Name Description

0x044D [7:3] Reserved Default: 0x00.

[2:1] REFB priority These bits set the priority level (0 to 3) of REFB relative to the other input references.

00 (default) = 0 (highest).

01 = 1.

10 = 2.

11 = 3.

0 Enable REFB This bit enables DPLL_0 to lock to REFB.

0 (default) = REFB is not enabled for use by DPLL_0.

1 = REFB is enabled for use by DPLL_0.

AD9554-1 Data Sheet

Rev. C | Page 76 of 99

Table 77. DPLL_0 REFB Loop Bandwidth Scaling Factor

Address Bits Bit Name Description

0x044E [7:0]

Digital PLL_0 loop

bandwidth scaling factor

(unit of 0.1 Hz)

Digital PLL_0 loop bandwidth scaling factor, Bits[7:0]. Default: 0x00. Operation with the

digital PLL_0 loop bandwidth scaling factor set to zero is undefined.

0x044F [7:0] Digital PLL_0 loop bandwidth scaling factor, Bits[15:8]. Default: 0x00. The default for

less than the DPLL phase detector frequency divided by 20. The DPLL may not lock

reliably if the DPLL loop bandwidth is <50 Hz and a crystal is used for the system clock.

See the Choosing the SYSCLK Source section for details.

0x0450 [7:2] Reserved Default: 0x00.

1 Base loop filter selection 0 = base loop filter with normal (70°) phase margin (default).

1 = base loop filter with high phase margin. (For loop bandwidths ≤2 kHz, there is

≤0.1 dB peaking in the closed-loop transfer function. Setting this bit is also

recommended for loop bandwidths >2 kHz.)

Digital PLL_0 loop

bandwidth scaling factor

(unit of 0.1 Hz)

Digital PLL loop bandwidth scaling factor, Bit 16. Default: 0b.

Table 78. DPLL_0 REFB Integer Part of Feedback (N0) Divider

Address Bits Bit Name Description

0x0451 [7:0] Digital PLL_0 feedback divider—Integer Part N0 Digital PLL_0 integer feedback divider (minus 1), Bits[7:0]. Default: 0x00.

0x0452 [7:0] Digital PLL_0 integer feedback divider, Bits[15:8]. Default: 0x00.

0x0453 [7:2] Reserved Default: 0x00.

[1:0] Digital PLL_0 feedback divider—Integer Part N0 Digital PLL_0 integer feedback divider, Bits[17:16]. Default: 00.

Table 79. DPLL_0 REFB Fractional Part of Fractional Feedback Divider—FRAC0

Address Bits Bit Name Description

0x0454 [7:0]

Digital PLL_0 fractional

feedback divider—FRAC0

The numerator of the fractional-N feedback divider, Bits[7:0]. Default: 0x00.

0x0455 [7:0] The numerator of the fractional-N feedback divider, Bits[15:8]. Default: 0x00.

0x0456 [7:0] The numerator of the fractional-N feedback divider, Bits[23:16]. Default: 0x00.

Table 80. DPLL_0 REFB Modulus of Fractional Feedback Divider—MOD0

Address Bits Bit Name Description

0x0457 [7:0]

Digital PLL_0 feedback

divider modulus—MOD0

The denominator of the fractional-N feedback divider, Bits[7:0]. Default: 0x00.

0x0458 [7:0] The denominator of the fractional-N feedback divider, Bits[15:8]. Default: 0x00.

0x0459 [7:0] The denominator of the fractional-N feedback divider, Bits[23:16]. Default: 0x00.

DPLL_0 SETTINGS FOR REFERENCE INPUT C (REFC) (REGISTER 0x045A TO REGISTER 0x0466)

Table 81. DPLL_0 REFC Priority Setting

Address Bits Bit Name Description

0x045A [7:3] Reserved Default: 00000b.

[2:1] REFC priority These bits set the priority level (0 to 3) of REFC relative to the other input references.

00 (default) = 0 (highest).

01 = 1.

10 = 2.

11 = 3.

0 Enable REFC This bit enables DPLL_0 to lock to REFC.

0 (default) = REFC is not enabled for use by DPLL_0.

1 = REFC is enabled for use by DPLL_0.

Data Sheet AD9554-1

Rev. C | Page 77 of 99

Table 82. DPLL_0 REFC Loop Bandwidth Scaling Factor

Address Bits Bit Name Description

0x045B [7:0]

Digital PLL_0 loop

bandwidth scaling factor

(unit of 0.1 Hz)

Digital PLL_0 loop bandwidth scaling factor, Bits[7:0]. Default: 0x00.

0x045C [7:0] Digital PLL_0 loop bandwidth scaling factor, Bits[15:8]. Default: 0x00. The default for

less than the DPLL phase detector frequency divided by 20. The DPLL may not lock

reliably if the DPLL loop bandwidth is <50 Hz and a crystal is used for the system clock.

See the Choosing the SYSCLK Source section for details.

0x045D [7:2] Reserved Default: 0x00.

1 Base loop filter selection 0 = base loop filter with normal (70°) phase margin (default).

1 = base loop filter with high phase margin. For loop bandwidth ≤2 kHz, there is ≤0.1 dB

peaking in the closed-loop transfer function. Setting this bit is also recommended for

loop bandwidths >2 kHz.

Digital PLL_0 loop bandwidth

scaling factor (unit of 0.1 Hz)

Digital PLL_0 loop bandwidth scaling factor, Bit 16 (default: 0b).

Table 83. DPLL_0 REFC Integer Part of Feedback (N0) Divider

Address Bits Bit Name Description

0x045E [7:0]

Digital PLL_0 feedback

divider—Integer Part N0

Digital PLL_0 integer feedback divider (minus 1), Bits[7:0]. Default: 0x00.

0x045F [7:0] Digital PLL_0 integer feedback divider, Bits[15:8]. Default: 0x00.

0x0460 [7:2] Reserved Default: 0x00.

[1:0]

Digital PLL_0 feedback

divider—Integer Part N0

Digital PLL_0 integer feedback divider, Bits[17:16]. Default: 00b. The default for

Table 84. DPLL_0 REFC Fractional Part of Fractional Feedback Divider—FRAC0

Address Bits Bit Name Description

0x0461 [7:0]

Digital PLL_0 fractional

feedback divider—FRAC0

The numerator of the fractional-N feedback divider, Bits[7:0]. Default: 0x00.

0x0462 [7:0] The numerator of the fractional-N feedback divider, Bits[15:8]. Default: 0x00.

0x0463 [7:0] The numerator of the fractional-N feedback divider, Bits[23:16]. Default: 0x00.

Table 85. DPLL_0 REFC Modulus of Fractional Feedback Divider—MOD0

Address Bits Bit Name Description

0x0464 [7:0]

Digital PLL_0 feedback

divider modulus—MOD0

The denominator of the fractional-N feedback divider, Bits[7:0]. Default: 0x00.

0x0465 [7:0] The denominator of the fractional-N feedback divider, Bits[15:8]. Default: 0x00.

0x0466 [7:0] The denominator of the fractional-N feedback divider, Bits[23:16]. Default: 0x00.

DPLL_0 SETTINGS FOR REFERENCE INPUT D (REFD) (REGISTER 0x0467 TO REGISTER 0x0473)

Table 86. DPLL_0 REFD Priority Setting

Address Bits Bit Name Description

0x0467 [7:3] Reserved Default: 00000b.

[2:1] REFD priority These bits set the priority level (0 to 3) of REFD relative to the other input references.

00 (default) = 0 (highest).

01 = 1.

10 = 2.

11 = 3.

0 Enable REFD This bit enables DPLL_0 to lock to REFD.

0 (default) = REFD is not enabled for use by DPLL_0.

1 = REFD is enabled for use by DPLL_0.

AD9554-1 Data Sheet

Rev. C | Page 78 of 99

Table 87. DPLL_0 REFD Loop Bandwidth Scaling Factor

Address Bits Bit Name Description

0x0468 [7:0]

Digital PLL_0 loop

bandwidth scaling factor

(unit of 0.1 Hz)

Digital PLL_0 loop bandwidth scaling factor, Bits[7:0]. Default: 0x00.

0x0469 [7:0] Digital PLL_0 loop bandwidth scaling factor, Bits[15:8]. Default: 0x00. The loop

bandwidth must always be less than the DPLL phase detector frequency divided by 20.

The DPLL may not lock reliably if the DPLL loop bandwidth is <50 Hz and a crystal is used

for the system clock. See the Choosing the SYSCLK Source section for details.

0x046A [7:2] Reserved Default: 0x00.

1 Base loop filter selection 0 = base loop filter with normal (70°) phase margin (default).

1 = base loop filter with high phase margin. For loop bandwidths ≤2 kHz, there is ≤0.1 dB

peaking in the closed-loop transfer function. Setting this bit is also recommended for

loop bandwidths >2 kHz.

Digital PLL_0 loop

bandwidth scaling factor

(unit of 0.1 Hz)

Digital PLL loop bandwidth scaling factor, Bit 16. Default: 0b.

Table 88. DPLL_0 REFD Integer Part of Feedback (N0) Divider

Address Bits Bit Name Description

0x046B [7:0] Digital PLL_0 feedback divider—Integer Part N0 Digital PLL_0 integer feedback divider (minus 1), Bits[7:0]. Default: 0x00.

0x046C [7:0] Digital PLL_0 integer feedback divider, Bits[15:8]. Default: 0x00.

0x046D [7:2] Reserved Default: 0x00.

[1:0] Digital PLL_0 feedback divider—Integer Part N0 Digital PLL_0 integer feedback divider, Bits[17:16]. Default: 00b.

Table 89. DPLL_0 REFD Fractional Part of Fractional Feedback Divider—FRAC0

Address Bits Bit Name Description

0x046E [7:0]

Digital PLL_0 fractional

feedback divider—FRAC0

The numerator of the fractional-N feedback divider, Bits[7:0]. Default: 0x00.

0x046F [7:0] The numerator of the fractional-N feedback divider, Bits[15:8]. Default: 0x00.

0x0470 [7:0] The numerator of the fractional-N feedback divider, Bits[23:16]. Default: 0x00.

Table 90. DPLL_0 REFD Modulus of Fractional Feedback Divider—MOD0

Address Bits Bit Name Description

0x0471 [7:0]

Digital PLL_0 feedback

divider modulus—MOD0

The denominator of the fractional-N feedback divider, Bits[7:0]. Default: 0x00.

0x0472 [7:0] The denominator of the fractional-N feedback divider, Bits[15:8]. Default: 0x00.

0x0473 [7:0] The denominator of the fractional-N feedback divider, Bits[23:16]. Default: 0x00.

DPLL_1 CONTROLS (REGISTER 0x0500 TO REGISTER 0x051E)

These registers mimic the DPLL_0 general settings registers (Register 0x0400 through Register 0x041E) but the register addresses are

offset by 0x0100. All default values are identical.

APLL_1 CONFIGURATION (REGISTER 0x0530 TO REGISTER 0x0533)

These registers mimic the APLL_0 configuration registers (Register 0x0430 through Register 0x0433) but the register addresses are offset

by 0x0100. All default values are identical.

PLL_1 OUTPUT SYNC AND CLOCK DISTRIBUTION (REGISTER 0x0534 TO REGISTER 0x053E)

These registers mimic the PLL_0 output SYNC and clock distribution registers (Register 0x0434 through Register 0x043E) but the register

addresses are offset by 0x0100. All default values are identical.

DPLL_1 SETTINGS FOR REFERENCE INPUT A (REFA) (REGISTER 0x0540 TO REGISTER 0x054C)

These registers mimic the DPLL_0 settings for the Reference Input A (REFA) registers (Register 0x0440 through Register 0x044C) but the

DPLL_1 SETTINGS FOR REFERENCE INPUT B (REFB) (REGISTER 0x054D TO REGISTER 0x0559)

These registers mimic the DPLL_0 settings for the Reference Input B (REFB) registers (Register 0x044D through Register 0x0459) but the

Data Sheet AD9554-1

Rev. C | Page 79 of 99

DPLL_1 SETTINGS FOR REFERENCE INPUT C (REFC) (REGISTER 0x055A TO REGISTER 0x0566)

These registers mimic the DPLL_0 settings for the Reference Input C (REFC) registers (Register 0x045A through Register 0x0466) but the

DPLL_1 SETTINGS FOR REFERENCE INPUT D (REFD) (REGISTER 0x0567 TO REGISTER 0x0573)

These registers mimic the DPLL_0 settings for the Reference Input D (REFD) registers (Register 0x0467 through Register 0x0473) but the

DPLL_2 CONTROLS (REGISTER 0x0600 TO REGISTER 0x061E)

These registers mimic the DPLL_0 controls registers (Register 0x0400 through Register 0x041E) but the register addresses are offset by

0x0200. All default values are identical.

APLL_2 CONFIGURATION (REGISTER 0x0630 TO REGISTER 0x0633)

These registers mimic the APLL_0 configuration registers (Register 0x0430 through Register 0x0433) but the register addresses are offset

by 0x0200. All default values are identical.

PLL_2 OUTPUT SYNC AND CLOCK DISTRIBUTION (REGISTER 0x0634 TO REGISTER 0x063E)

These registers mimic the PLL_0 output SYNC and clock distribution registers (Register 0x0434 through Register 0x043E) but the register

addresses are offset by 0x0200. All default values are identical.

DPLL_2 SETTINGS FOR REFERENCE INPUT A (REFA) (REGISTER 0x0640 TO REGISTER 0x064C)

These registers mimic the DPLL_0 settings for the Reference Input A (REFA) registers (Register 0x0440 through Register 0x044C) but the

DPLL_2 SETTINGS FOR REFERENCE INPUT B (REFB) (REGISTER 0x064D TO REGISTER 0x0659)

These registers mimic the DPLL_0 settings for the Reference Input B (REFB) registers (Register 0x044D through Register 0x0459) but the

DPLL_2 SETTINGS FOR REFERENCE INPUT C (REFC) (REGISTER 0x065A TO REGISTER 0x0666)

These registers mimic the DPLL_0 settings for the Reference Input C (REFC) registers (Register 0x045A through Register 0x0466) but the

DPLL_2 SETTINGS FOR REFERENCE INPUT D (REFD) (REGISTER 0x0667 TO REGISTER 0x0673)

These registers mimic the DPLL_0 settings for the Reference Input D (REFD) registers (Register 0x0467 through Register 0x0473) but the

DPLL_3 CONTROLS (REGISTER 0x0700 TO REGISTER 0x071E)

These registers mimic the DPLL_0 controls registers (Register 0x0400 through Register 0x041E) but the register addresses are offset by

0x0300. All default values are identical.

APLL_3 CONFIGURATION (REGISTER 0x0730 TO REGISTER 0x0733)

These registers mimic the APLL_0 configuration registers (Register 0x0430 through Register 0x0433) but the register addresses are offset

by 0x0300. All default values are identical.

PLL_3 OUTPUT SYNC AND CLOCK DISTRIBUTION (REGISTER 0x0734 TO REGISTER 0x073E)

These registers mimic the PLL_0 output SYNC and clock distribution registers (Register 0x0434 through Register 0x043E) but the register

addresses are offset by 0x0300. All default values are identical.

DPLL_3 SETTINGS FOR REFERENCE INPUT A (REFA) (REGISTER 0x0740 TO REGISTER 0x074C)

These registers mimic the DPLL_0 settings for the Reference Input A (REFA) registers (Register 0x0440 through Register 0x044C) but the

DPLL_3 SETTINGS FOR REFERENCE INPUT B (REFB) (REGISTER 0x074D TO REGISTER 0x0759)

These registers mimic the DPLL_0 settings for the Reference Input B (REFB) registers (Register 0x044D through Register 0x0459) but the

AD9554-1 Data Sheet

Rev. C | Page 80 of 99

DPLL_3 SETTINGS FOR REFERENCE INPUT C (REFC) (REGISTER 0x075A TO REGISTER 0x0766)

These registers mimic the DPLL_0 settings for the Reference Input C (REFC) registers (Register 0x045A through Register 0x0466) but the

DPLL_3 SETTINGS FOR REFERENCE INPUT D (REFD) (REGISTER 0x0767 TO REGISTER 0x0773)

These registers mimic the DPLL_0 settings for the Reference Input D (REFD) registers (Register 0x0467 through Register 0x0473) but the

DIGITAL LOOP FILTER COEFFICIENTS (REGISTER 0x0800 TO REGISTER 0x0817)

Note that the digital loop filter base coefficients (α, β, γ, and δ) have the general form: x(2y), where x is the linear component, and y is the

exponential component of the coefficient. The value of the linear component (x) constitutes a fraction, where 0 ≤ x ≤ 1. The exponential

component (y) is a signed integer. These are live registers; therefore, an IO_UPDATE is not needed. However, the updated coefficients do

not take effect while the loop is active.

Table 91. Base Digital Loop Filter with Normal Phase Margin (PM = 70°)

Address Bits Bit Name Description

0x0800 [7:0] NPM Alpha-0 linear Alpha-0 coefficient linear, Bits[7:0]. Default: 0x24.

0x0801 [7:0] Alpha-0 coefficient linear, Bits[15:8]. Default: 0x8C.

0x0802 7 Reserved Default: 0b.

[6:0] NPM Alpha-1 exponent Alpha-1 coefficient exponent, Bits[6:0]. Default: 0x49.

0x0803 [7:0] NPM Beta-0 linear Beta-0 coefficient linear, Bits[7:0]. Default: 0x55.

0x0804 [7:0] Beta-0 coefficient linear, Bits[15:8]. Default: 0xC9.

0x0805 7 Reserved Default: 0b.

[6:0] NPM Beta-1 exponent Beta-1 coefficient exponent, Bits[6:0]. Default: 0x7B.

0x0806 [7:0] NPM Gamma-0 linear Gamma-0 coefficient linear, Bits[7:0]. Default: 0x9C.

0x0807 [7:0] Gamma-0 coefficient linear, Bits[15:8]. Default: 0xFA.

0x0808 7 Reserved Default: 0b.

[6:0] NPM Gamma -1 exponent Gamma-1 coefficient exponent, Bits[6:0]. Default: 0x55.

0x0809 [7:0] NPM Delta-0 linear Delta-0 coefficient linear, Bits[7:0]. Default: 0xEA.

0x080A [7:0] Delta-0 coefficient linear, Bits[15:8]. Default: 0xE2.

0x080B 7 Reserved Default: 0b.

[6:0] NPM Delta-1 exponent Delta-1 coefficient exponent, Bits[6:0]. Default: 0x57.

Note that the base digital loop filter coefficients (α, β, γ, and δ) have the general form: x(2y), where x is the linear component, and y is the

exponential component of the coefficient. The value of the linear component (x) constitutes a fraction, where 0 ≤ x ≤ 1. The exponential

component (y) is a signed integer. These are live registers; therefore, an IO_UPDATE is not needed. However, the updated coefficients do

not take effect while the loop is active.

Table 92. Base Digital Loop Filter with High Phase Margin (PM = 88.5°)

Address Bits Bit Name Description

0x080C [7:0] HPM Alpha-0 linear Alpha-0 coefficient linear, Bits[7:0]. Default = 0x8C.

0x080D [7:0] Alpha-0 coefficient linear, Bits[15:8]. Default: 0xAD.

0x080E 7 Reserved Default: 0b.

[6:0] HPM Alpha-1 exponent Alpha-1 coefficient exponent, Bits[6:0]. Default: 0x4C.

0x080F [7:0] HPM Beta-0 linear Beta-0 coefficient linear, Bits[7:0]. Default: 0xF5.

0x0810 [7:0] Beta-0 coefficient linear, Bits[15:8]. Default: 0xCB.

0x0811 7 Reserved Default: 0b.

[6:0] HPM Beta-1 exponent Beta-1 coefficient exponent, Bits[6:0]. Default: 0x73.

0x0812 [7:0] HPM Gamma-0 linear Gamma-0 coefficient linear, Bits[7:0]. Default: 0x24.

0x0813 [7:0] Gamma-0 coefficient linear, Bits[15:8]. Default: 0xD8.

0x0814 7 Reserved Default: 0b.

[6:0] HPM Gamma-1 exponent Gamma-1 coefficient exponent, Bits[6:0]. Default: 0x59.

0x0815 [7:0] HPM Delta-0 linear Delta-0 coefficient linear, Bits[7:0]. Default: 0xD2.

0x0816 [7:0] Delta-0 coefficient linear, Bits[15:8]. Default: 0x8D.

0x0817 7 Reserved Default: 0b.

[6:0] HPM Delta-1 exponent Delta-1 coefficient exponent, Bits[6:0]. Default: 0x5A.

Data Sheet AD9554-1

Rev. C | Page 81 of 99

Table 93. Global Demapping Control

Address Bits Bit Name Description

0x0900 [7:1] Reserved Reserved, Bits[7:1]. Default = 0x00.

0 Demap control IO_UPDATE Demap control IO_UPDATE, Bit 0. Default = 0b.

0x0901 [7:0] DPLL_0 sampled address, Bits[15:0] DPLL_0 sampled address, Bits[7:0]. Default = 0x00.

0x0902 [7:0] DPLL_0 sampled address, Bits[15:8]. Default: 0x00.

0x0903 [7:0] DPLL_1 sampled address, Bits[15:0] DPLL_1 sampled address, Bits[7:0]. Default = 0x00.

0x0904 [7:0] DPLL_1 sampled address, Bits[15:8]. Default: 0x00.

0x0905 [7:0] DPLL_2 sampled address, Bits[15:0] DPLL_2 sampled address, Bits[7:0]. Default = 0x00.

0x0906 [7:0] DPLL_2 sampled address, Bits[15:8]. Default: 0x00

0x0907 [7:0] DPLL_3 sampled address, Bits[15:0] DPLL_3 sampled address, Bits[7:0]. Default = 0x00.

0x0908 [7:0] DPLL_3 sampled address, Bits[15:8]. Default: 0x00.

0x0909 [7:1] Reserved Reserved, Bits[7:1]. Default = 0x00.

0 Demap control IO_UPDATE Demap control IO_UPDATE, Bit 0. Default = 0b.

COMMON OPERATIONAL CONTROLS (REGISTER 0x0A00 TO REGISTER 0x0A0E)

Table 94. Global Operational Controls

Address Bits Bit Name Description

0x0A00 [7:4] Reserved Default: 0x0.

3 Soft sync all Setting this bit initiates synchronization of all clock distribution outputs (default = 0b).

Nonmasked outputs stall when value is 1; restart is initialized on a 1-to-0 transition. Note

that like all buffered registers, an IO_UPDATE (0x000F = 0x01) is needed every time there is

a change for this bit to take effect.

2 Calibrate SYSCLK

A 0-to-1 transition of this bit (followed by an IO_UPDATE) calibrates the SYSCLK PLL.

Default: 0b.

1 Calibrate all A 0-to-1 transition of this bit (followed by an IO_UPDATE) calibrates the system clock PLL, as

well as all four output PLLs (APLL_0, APLL_1, APLL_2, APLL_3). Default = 0b. Like all buffered

registers, an IO_UPDATE (0x000F = 0x01) is needed every time there is a change for this bit

to take effect. This bit is not self clearing; however, it is strongly recommended to clear this

bit after using it. If this bit is set, calibration of the individual APLLs (APLL_0, APLL_1, APLL_2, and

APLL_3) in Register 0xA20, Register 0xA40, Register 0xA60, and Register 0xA80 is masked

and APLL calibration does not occur.

0 Power-down all Places the entire device in deep sleep mode. Default: device is not powered down.

Table 95. Power Down of Reference Inputs

Address Bits Bit Name Description

0x0A01 [7:4] Reserved Default: 0x0

3 REFD power-down Powers down REFD input receiver

0 (default) = not powered down

1 = powered down

2 REFC power-down Powers down REFC input receiver

0 (default) = not powered down

1 = powered down

1 REFB power-down Powers down REFB input receiver

0 (default) = not powered down

1 = powered down

0 REFA power-down Powers down REFA input receiver

0 (default) = not powered down

1 = powered down

AD9554-1 Data Sheet

Rev. C | Page 82 of 99

Table 96. Reference Input Validation Timeout

Address Bits Bit Name Description

0x0A02 [7:4] Reserved Default: 0x0.

3 REFD timeout If REFD is unfaulted, setting this autoclearing bit forces the reference validation timer for

REFD to zero, thus making it valid immediately. Default = 0b.

2 REFC timeout If REFC is unfaulted, setting this autoclearing bit forces the reference validation timer for

REFC to zero, thus making it valid immediately. Default = 0b.

1 REFB timeout If REFB is unfaulted, setting this autoclearing bit forces the reference validation timer for

REFB to zero, thus making it valid immediately. Default = 0b.

0 REFA timeout If REFA is unfaulted, setting this autoclearing bit forces the reference validation timer for

REFA to zero, thus making it valid immediately. Default = 0b.

Table 97. Force Reference Input Fault

Address Bits Bit Name Description

0x0A03 [7:4] Reserved Default: 0x0

3 REFD fault Faults REFD input receiver

0 (default) = not faulted

1 = faulted (REFD is not used)

2 REFC fault Faults REFC input receiver

0 (default) = not faulted

1 = faulted (REFC is not used)

1 REFB fault Faults REFB input receiver

0 (default) = not faulted

1 = faulted (REFB is not used)

0 REFA fault Faults REFA input receiver

0 (default) = not faulted

1 = faulted (REFA is not used)

Table 98. Reference Input Monitor Bypass

Address Bits Bit Name Description

0x0A04 [7:4] Reserved Default: 0x0

3 REFD monitor bypass Bypasses REFD input receiver frequency monitor; setting this bit to 1 forces REFD to be

unfaulted as long as the REFD fault bit in Register 0x0A03 is not set.

0 (default) = REFD frequency monitor not bypassed.

1 = REFD frequency monitor bypassed.

2 REFC monitor bypass Bypasses REFC input receiver frequency monitor; setting this bit to 1 forces REFC to be

unfaulted as long as the REFC fault bit in Register 0x0A03 is not set.

0 (default) = REFC frequency monitor not bypassed.

1 = REFC frequency monitor bypassed.

1 REFB monitor bypass Bypasses REFB input receiver frequency monitor; setting this bit to 1 forces REFB to be

unfaulted as long as the REFB fault bit in Register 0x0A03 is not set.

0 (default) = REFB frequency monitor not bypassed.

1 = REFBB frequency monitor bypassed.

0 REFA monitor bypass Bypasses REFA input receiver frequency monitor; setting this bit to 1 forces REFA to be

unfaulted as long as the REFA fault bit in Register 0x0A03 is not set.

0 (default) = REFA frequency monitor not bypassed.

1 = REFA frequency monitor bypassed.

Data Sheet AD9554-1

Rev. C | Page 83 of 99

IRQ CLEARING (REGISTER 0x0A05 TO REGISTER 0x0A14)

The IRQ clearing registers are identical in format to the IRQ monitor registers (Register 0x0D08 to Register 0x0D16). When set to Logic

1, an IRQ clearing bit resets the corresponding IRQ monitor bit, thereby cancelling the interrupt request for the indicated event. The IRQ

clearing registers are autoclearing.

Table 99. Clear IRQ Groups

Address Bits Bit Name Description

0x0A05 7 Clear watchdog timer Clears watchdog timer alert

6 Reserved Reserved

5 Clear DPLL_3 IRQs Clears all IRQs associated with DPLL_3

4 Clear DPLL_2 IRQs Clears all IRQs associated with DPLL_2

3 Clear DPLL_1 IRQs Clears all IRQs associated with DPLL_1

2 Clear DPLL_0 IRQs Clears all IRQs associated with DPLL_0

1 Clear common IRQs Clears all IRQs associated with common IRQ group

0 Clear all IRQs Clears all IRQs

Table 100. IRQ Clearing for SYSCLK

Address Bits Bit Name Description

0x0A06 7 SYSCLK unlocked Clears IRQ indicating a SYSCLK PLL state transition from locked to unlocked

6 SYSCLK stable Clears IRQ indicating that SYSCLK stability time has expired and that the SYSCLK PLL is

stable

5 SYSCLK locked Clears IRQ indicating a SYSCLK PLL state transition from unlocked to locked

4 SYSCLK cal ended Clears IRQ indicating a SYSCLK PLL calibration has ended

3 SYSCLK cal started Clears IRQ indicating a SYSCLK PLL calibration has started

2 Watchdog timer Clears IRQ indicating expiration of the watchdog timer

[1:0] Reserved Default: 00b

Table 101. IRQ Clearing for Reference Inputs

Address Bits Bit Name Description

0x0A07 7 Reserved Reserved

6 REFB validated Clears IRQ indicating that REFB has been validated

5 REFB fault cleared Clears IRQ indicating that REFB has been cleared of a previous fault

4 REFB fault Clears IRQ indicating that REFB has been faulted

3 Reserved Reserved

2 REFA validated Clears IRQ indicating that REFA has been validated

1 REFA fault cleared Clears IRQ indicating that REFA has been cleared of a previous fault

0 REFA fault Clears IRQ indicating that REFA has been faulted

0x0A08 7 Reserved Reserved

6 REFD validated Clears IRQ indicating that REFD has been validated

5 REFD fault cleared Clears IRQ indicating that REFD has been cleared of a previous fault

4 REFD fault Clears IRQ indicating that REFD has been faulted

3 Reserved Reserved

2 REFC validated Clears IRQ indicating that REFC has been validated

1 REFC fault cleared Clears IRQ indicating that REFC has been cleared of a previous fault

0 REFC fault Clears IRQ indicating that REFC has been faulted

AD9554-1 Data Sheet

Rev. C | Page 84 of 99

Table 102. IRQ Clearing for Digital PLL0 (DPLL_0)

Address Bits Bit Name Description

0x0A09 7 Frequency unclamped Clears IRQ indicating that DPLL_0 has exited a frequency unclamped state

6 Frequency clamped Clears IRQ indicating that DPLL_0 has entered a frequency clamped state

5 Phase slew unlimited Clears IRQ indicating that DPLL_0 has exited a phase slew limited state

4 Phase slew limited Clears IRQ indicating that DPLL_0 has entered a phase slew limited state

3 Frequency unlocked Clears IRQ indicating that DPLL_0 has lost frequency lock

2 Frequency locked Clears IRQ indicating that DPLL_0 has acquired frequency lock

1 Phase unlocked Clears IRQ indicating that DPLL_0 has lost phase lock

0 Phase locked Clears IRQ indicating that DPLL_0 has acquired phase lock

0x0A0A 7 DPLL_0 switching Clears IRQ indicating that DPLL_0 is switching to a new reference

6 DPLL_0 free run Clears IRQ indicating that DPLL_0 has entered free run mode

5 DPLL_0 holdover Clears IRQ indicating that DPLL_0 has entered holdover mode

4 History updated Clears IRQ indicating that DPLL_0 has updated its tuning word history

3 REFD activated Clears IRQ indicating that DPLL_0 has activated REFD

2 REFC activated Clears IRQ indicating that DPLL_0 has activated REFC

1 REFB activated Clears IRQ indicating that DPLL_0 has activated REFB

0 REFA activated Clears IRQ indicating that DPLL_0 has activated REFA

0x0A0B 7 Phase step detected Clears IRQ indicating that DPLL_0 has detected a large phase step at its input

6 Demap control unclamped Clears IRQ indicating that the DPLL_0 demapping controller has an unclamped state

5 Demap control clamped Clears IRQ indicating that the DPLL_0 demapping controller has a clamped state

4 Clock dist sync’d Clears IRQ indicating a distribution sync event

3 APLL_0 unlocked Clears IRQ indicating that APLL_0 has been unlocked

2 APLL_0 locked Clears IRQ indicating that APLL_0 has been locked

1 APLL_0 cal ended Clears IRQ indicating that APLL_0 calibration complete

0 APLL_0 cal started Clears IRQ indicating that APLL_0 calibration started

Data Sheet AD9554-1

Rev. C | Page 85 of 99

Table 103. IRQ Clearing for Digital PLL1 (DPLL_1)

Address Bits Bit Name Description

0x0A0C 7 Frequency unclamped Clears IRQ indicating that DPLL_1 has exited a frequency unclamped state

6 Frequency clamped Clears IRQ indicating that DPLL_1 has entered a frequency clamped state

5 Phase slew unlimited Clears IRQ indicating that DPLL_1 has exited a phase slew limited state

4 Phase slew limited Clears IRQ indicating that DPLL_1 has entered a phase slew limited state

3 Frequency unlocked Clears IRQ indicating that DPLL_1 has lost frequency lock

2 Frequency locked Clears IRQ indicating that DPLL_1 has acquired frequency lock

1 Phase unlocked Clears IRQ indicating that DPLL_1 has lost phase lock

0 Phase locked Clears IRQ indicating that DPLL_1 has acquired phase lock

0x0A0D 7 DPLL_1 switching Clears IRQ indicating that DPLL_1 is switching to a new reference

6 DPLL_1 free run Clears IRQ indicating that DPLL_1 has entered free run mode

5 DPLL_1 holdover Clears IRQ indicating that DPLL_1 has entered holdover mode

4 History updated Clears IRQ indicating that DPLL_1 has updated its tuning word history

3 REFD activated Clears IRQ indicating that DPLL_1 has activated REFD

2 REFC activated Clears IRQ indicating that DPLL_1 has activated REFC

1 REFB activated Clears IRQ indicating that DPLL_1 has activated REFB

0 REFA activated Clears IRQ indicating that DPLL_1 has activated REFA

0x0A0E 7 Phase step detected Clears IRQ indicating that DPLL_1 has detected a large phase step at its input

6 Demap control unclamped Clears IRQ indicating that the DPLL_1 demapping controller has an unclamped state

5 Demap control clamped Clears IRQ indicating that the DPLL_1 demapping controller has a clamped state

4 Clock dist sync’d Clears IRQ indicating a distribution sync event

3 APLL_1 unlocked Clears IRQ indicating that APLL_1 has been unlocked

2 APLL_1 locked Clears IRQ indicating that APLL_1 has been locked

1 APLL_1 cal ended Clears IRQ indicating that APLL_1 calibration complete

0 APLL_1 cal started Clears IRQ indicating that APLL_1 calibration started

Table 104. IRQ Clearing for Digital PLL2 (DPLL_2)

Address Bits Bit Name Description

0x0A0F 7 Frequency unclamped Clears IRQ indicating that DPLL_2 has exited a frequency unclamped state

6 Frequency clamped Clears IRQ indicating that DPLL_2 has entered a frequency clamped state

5 Phase slew unlimited Clears IRQ indicating that DPLL_2 has exited a phase slew limited state

4 Phase slew limited Clears IRQ indicating that DPLL_2 has entered a phase slew limited state

3 Frequency unlocked Clears IRQ indicating that DPLL_2 has lost frequency lock

2 Frequency locked Clears IRQ indicating that DPLL_2 has acquired frequency lock

1 Phase unlocked Clears IRQ indicating that DPLL_2 has lost phase lock

0 Phase locked Clears IRQ indicating that DPLL_2 has acquired phase lock

0x0A10 7 DPLL_2 switching Clears IRQ indicating that DPLL_2 is switching to a new reference

6 DPLL_2 free run Clears IRQ indicating that DPLL_2 has entered free run mode

5 DPLL_2 holdover Clears IRQ indicating that DPLL_2 has entered holdover mode

4 History updated Clears IRQ indicating that DPLL_2 has updated its tuning word history

3 REFD activated Clears IRQ indicating that DPLL_2 has activated REFD

2 REFC activated Clears IRQ indicating that DPLL_2 has activated REFC

1 REFB activated Clears IRQ indicating that DPLL_2 has activated REFB

0 REFA activated Clears IRQ indicating that DPLL_2 has activated REFA

AD9554-1 Data Sheet

Rev. C | Page 86 of 99

Address Bits Bit Name Description

0x0A11 7 Phase step detected Clears IRQ indicating that DPLL_2 has detected a large phase step at its input

6 Demap control unclamped Clears IRQ indicating that the DPLL_2 demapping controller is unclamped

5 Demap control clamped Clears IRQ indicating that the DPLL_2 demapping controller is clamped

4 Clock dist sync’d Clears IRQ indicating a distribution sync event

3 APLL_2 unlocked Clears IRQ indicating that APLL_2 has been unlocked

2 APLL_2 locked Clears IRQ indicating that APLL_2 has been locked

1 APLL_2 cal ended Clears IRQ indicating that APLL_2 calibration complete

0 APLL_2 cal started Clears IRQ indicating that APLL_2 calibration started

Table 105. IRQ Clearing for Digital PLL3 (DPLL_3)

Address Bits Bit Name Description

0x0A12 7 Frequency unclamped Clears IRQ indicating that DPLL_3 has exited a frequency unclamped state

6 Frequency clamped Clears IRQ indicating that DPLL_3 has entered a frequency clamped state

5 Phase slew unlimited Clears IRQ indicating that DPLL_3 has exited a phase slew limited state

4 Phase slew limited Clears IRQ indicating that DPLL_3 has entered a phase slew limited state

3 Frequency unlocked Clears IRQ indicating that DPLL_3 has lost frequency lock

2 Frequency locked Clears IRQ indicating that DPLL_3 has acquired frequency lock

1 Phase unlocked Clears IRQ indicating that DPLL_3 has lost phase lock

0 Phase locked Clears IRQ indicating that DPLL_3 has acquired phase lock

0x0A13 7 DPLL_3 switching Clears IRQ indicating that DPLL_3 is switching to a new reference

6 DPLL_3 free run Clears IRQ indicating that DPLL_3 has entered free run mode

5 DPLL_3 holdover Clears IRQ indicating that DPLL_3 has entered holdover mode

4 History updated Clears IRQ indicating that DPLL_3 has updated its tuning word history

3 REFD activated Clears IRQ indicating that DPLL_3 has activated REFD

2 REFC activated Clears IRQ indicating that DPLL_3 has activated REFC

1 REFB activated Clears IRQ indicating that DPLL_3 has activated REFB

0 REFA activated Clears IRQ indicating that DPLL_3 has activated REFA

0x0A14 7 Phase step detected Clears IRQ indicating that DPLL_3 has detected a large phase step at its input

6 Demap control unclamped Clears IRQ indicating that the DPLL_3 demapping controller is unclamped

5 Demap control clamped Clears IRQ indicating that the DPLL_3 demapping controller is clamped

4 Clock dist sync’d Clears IRQ indicating a distribution sync event

3 APLL_3 unlocked Clears IRQ indicating that APLL_3 has been unlocked

2 APLL_3 locked Clears IRQ indicating that APLL_3 has been locked

1 APLL_3 cal ended Clears IRQ indicating that APLL_3 calibration complete

0 APLL_3 cal started Clears IRQ indicating that APLL_3 calibration started

PLL_0 OPERATIONAL CONTROLS (REGISTER 0x0A20 TO REGISTER 0x0A24)

Table 106. PLL_0 Sync and Calibration

Address Bits Bit Name Description

0x0A20 [7:3] Reserved Default: 0x0.

2 APLL_0 soft sync Setting this bit initiates synchronization of the clock distribution output.

0 (default) = normal operation.

1 = nonmasked PLL_0 outputs stall; restart initialized on a 1-to-0 transition.

APLL_0 calibrate (not self-

clearing)

1 = initiates VCO calibration (calibration occurs on the IO_UPDATE following a 0-to-1

transition of this bit). This bit is not autoclearing.

0 (default) = does nothing.

0 PLL_0 power-down Places DPLL_0, APLL_0, and PLL_0 clock in deep sleep mode.

0 (default) = normal operation.

1 = powered down.

Data Sheet AD9554-1

Rev. C | Page 87 of 99

Table 107. PLL_0 Output

Address Bits Bit Name Description

0x0A21 [7:4] Reserved Default 0x0

3 OUT0B disable Setting this bit puts the OUT0B driver into power-down. Default: 0b. Channel

synchronization is maintained, but runt pulses may be generated.

2 Reserved Default: 0b.

1 OUT0B power-down Setting this bit puts the OUT0B divider and driver into power-down. Default: 0b. This

mode saves the most power, but runt pulses may be generated during exit.

0 Reserved Default: 0b.

Table 108. PLL_0 User Mode

Address Bits Bit Name Description

0x0A22 7 Reserved Default: 0b.

[6:5] DPLL_0 manual reference Input reference when user selection mode = 00, 01, 10, or 11.

00 (default) = Input Reference A.

01 = Input Reference B.

10 = Input Reference C.

11 = Input Reference D.

[4:2] DPLL_0 switching mode Selects the operating mode of the reference switching state machine.

Reference Switchover

Mode, Bits[2:0] Reference Selection Mode

000b Automatic revertive mode

001b Automatic nonrevertive mode

010b Manual reference select mode (with automatic fallback)

011b Manual reference select mode (with holdover fallback)

100b Manual reference select mode (without holdover fallback)

101b Not used

110b Not used

111b Not used

1 DPLL_0 user holdover Forces DPLL_0 into holdover mode. Note that the AD9554-1 enters free run mode if this bit

is set when there is no holdover history available.

0 (default) = normal operation.

1 = DPLL_0 is forced into holdover mode until this bit is cleared. Note that holdover mode is

used if the holdover history is available. User free run mode is used if the holdover history is

not available. See Register 0x0D22, Bit 0 for the DPLL_0 history available indication.

0 DPLL_0 user free run Forces DPLL_0 into free run mode.

0 (default) = normal operation.

1 = DPLL_0 is forced into free run mode until this bit is cleared.

Table 109. PLL_0 Reset

Address Bits Bit Name Description

0x0A23 [7:3] Reserved Default: 00000b.

2 Reset DPLL_0 loop filter Resets the digital loop filter.

0 (default) = normal operation.

1 = DPLL_0 digital loop filter is reset. This is an autoclearing bit.

1 Reset DPLL_0 TW history Resets the tuning word history (part of holdover functionality).

0 (default) = normal operation.

1 = DPLL_0 tuning word history is reset. This is an autoclearing bit.

0 Reset DPLL_0 autosync Resets the automatic synchronization logic (see Register 0x0435).

0 (default) = normal operation.

1 = DPLL_0 automatic synchronization logic is reset. This is an autoclearing bit.

AD9554-1 Data Sheet

Rev. C | Page 88 of 99

Table 110. PLL_0 Phase

Address Bits Bit Name Description

0x0A24 [7:3] Reserved Default: 00000b.

2 DPLL_0 reset phase offset Resets the incremental phase offset to zero. This is an autoclearing bit.

1 DPLL_0 decrement phase offset Decrements the incremental phase offset by the amount specified in the incremental

phase lock offset step size registers (Register 0x0412 and Register 0x0413). This is an

autoclearing bit.

0 DPLL_0 increment phase offset Increments the incremental phase offset by the amount specified in the incremental

phase lock offset step size registers (Register 0x0412 and Register 0x0413). This is an

autoclearing bit.

PLL_1 OPERATIONAL CONTROLS (REGISTER 0x0A40 TO REGISTER 0x0A44)

These registers mimic the PLL_0 controls registers (Register 0x0A20 through Register 0x0A24) but the register addresses are offset by

0x0020. All default values are identical.

PLL_2 OPERATIONAL CONTROLS (REGISTER 0x0A60 TO REGISTER 0x0A64)

These registers mimic the PLL_0 controls registers (Register 0x0A20 through Register 0x0A24) but the register addresses are offset by

0x0040. All default values are identical.

PLL_3 OPERATIONAL CONTROLS (REGISTER 0x0A80 TO REGISTER 0x0A84)

These registers mimic the PLL_0 controls registers (Register 0x0A20 through Register 0x0A24) but the register addresses are offset by

0x0060. All default values are identical.

VOLTAGE REGULATOR (REGISTER 0x0B00 TO REGISTER 0x0B01)

The bits in these registers adjust the internal voltage regulator for 1.5 V input voltage operation.

Table 111. Voltage Regulator

Address Bits Bit Name Description

0x0B00 [7:0]

VREG,

Bits[7:0]

Adjusts internal voltage regulators for 1.5 V operation. There are only two valid settings for this register, and

all bits in VREG[9:0] must be all 1s or all 0s, depending on whether the device is powered at 1.5 V or 1.8 V.

0x00 (default) = 1.8 V operation.

0xFF = 1.5 V operation.

0x0B01 [7:2] Reserved Default: 000000b.

[1:0]

VREG,

Bits[9:8]

Adjusts internal voltage regulators for 1.5 V operation. There are only two valid settings for this register.

00b (default): 1.8 V operation.

11b: 1.5 V operation.

STATUS READBACK (REGISTER 0x0D01 TO REGISTER 0x0D05)

All bits in Register 0x0D01 to Register 0x0D05 are read only. To report the latest status, these bits require an IO_UPDATE

(Register 0x000F = 0x01) immediately before being read.

Table 112. SYSCLK and PLL Status

Address Bits Bit Name Description

0x0D01 7 PLL_3 all locked Indicates the status of the system clock, APLL_3, and DPLL_3.

0 = system clock or APLL_3 or DPLL_3 is unlocked.

1 = all three PLLs (system clock, APLL_3, and DPLL_3) are locked.

6 PLL_2 all locked Indicates the status of the system clock, APLL_2, and DPLL_2.

0 = system clock or APLL_2 or DPLL_2 is unlocked.

1 = all three PLLs (system clock, APLL_2, and DPLL_2) are locked.

5 PLL_1 all locked Indicates the status of the system clock, APLL_1, and DPLL_1.

0 = system clock or APLL_1 or DPLL_1 is unlocked.

1 = all three PLLs (system clock, APLL_1, and DPLL_1) are locked.

4 PLL_0 all locked Indicates the status of the system clock, APLL_0, and DPLL_0.

0 = system clock or APLL_0 or DPLL_0 is unlocked.

1 = all three PLLs (system clock, APLL_0, and DPLL_0) are locked.

Data Sheet AD9554-1

Rev. C | Page 89 of 99

Address Bits Bit Name Description

3 Reserved Default: 0b.

2 SYSCLK calibration busy Indicates the status of the system clock calibration.

0 (default) = normal operation.

1 = system clock calibration in progress.

1 SYSCLK stable The control logic sets this bit when the device considers the system clock to be stable (see the

System Clock Stability Timer section).

0 SYSCLK lock detect Indicates the status of the system clock PLL.

0 = unlocked.

1 = locked.

Table 113. Status of Reference Inputs

Address Bits Bit Name Description

0x0D02 7 DPLL_3 REFA active This bit is 1 if DPLL_3 is either locked to or attempting to lock to REFA.

6 DPLL_2 REFA active This bit is 1 if DPLL_2 is either locked to or attempting to lock to REFA.

5 DPLL_1 REFA active This bit is 1 if DPLL_1 is either locked to or attempting to lock to REFA.

4 DPLL_0 REFA active This bit is 1 if DPLL_0 is either locked to or attempting to lock to REFA.

3 REFA valid This bit is 1 if the REFA frequency is within the programmed limits and the validation timer has

expired.

2 REFA fault This bit is 1 if the REFA frequency is outside of the programmed limits.

1 REFA fast This bit is 1 if the REFA frequency is higher than allowed by its profile settings.

(Note that if no REFA input is detected, the REFA fast and slow bits may both be high.)

0 REFA slow This bit is 1 if the REFA frequency is lower than allowed by its profile settings.

0x0D03 7 DPLL_3 REFB active This bit is 1 if DPLL_3 is either locked to or attempting to lock to REFB.

6 DPLL_2 REFB active This bit is 1 if DPLL_2 is either locked to or attempting to lock to REFB.

5 DPLL_1 REFB active This bit is 1 if DPLL_1 is either locked to or attempting to lock to REFB.

4 DPLL_0 REFB active This bit is 1 if DPLL_0 is either locked to or attempting to lock to REFB.

3 REFB valid This bit is 1 if the REFB frequency is within the programmed limits and the validation timer has

expired.

2 REFB fault This bit is 1 if the REFB frequency is outside of the programmed limits.

1 REFB fast This bit is 1 if the REFB frequency is higher than allowed by its profile settings.

(Note that if no REFB input is detected, the REFB fast and slow bits may both be high.)

0 REFB slow This bit is 1 if the REFB frequency is lower than allowed by its profile settings.

0x0D04 7 DPLL_3 REFC active This bit is 1 if DPLL_3 is either locked to or attempting to lock to REFC.

6 DPLL_2 REFC active This bit is 1 if DPLL_2 is either locked to or attempting to lock to REFC.

5 DPLL_1 REFC active This bit is 1 if DPLL_1 is either locked to or attempting to lock to REFC.

4 DPLL_0 REFC active This bit is 1 if DPLL_0 is either locked to or attempting to lock to REFC.

3 REFC valid This bit is 1 if the REFC frequency is within the programmed limits and the validation timer has

expired.

2 REFC fault This bit is 1 if the REFC frequency is outside of the programmed limits.

1 REFC fast This bit is 1 if the REFC frequency is higher than allowed by its profile settings.

(Note that if no REFC input is detected, the REFC fast and slow bits may both be high.)

0 REFC slow This bit is 1 if the REFC frequency is lower than allowed by its profile settings.

0x0D05 7 DPLL_3 REFD active This bit is 1 if DPLL_3 is either locked to or attempting to lock to REFD.

6 DPLL_2 REFD active This bit is 1 if DPLL_2 is either locked to or attempting to lock to REFD.

5 DPLL_1 REFD active This bit is 1 if DPLL_1 is either locked to or attempting to lock to REFD.

4 DPLL_0 REFD active This bit is 1 if DPLL_0 is either locked to or attempting to lock to REFD.

3 REFD valid This bit is 1 if the REFD frequency is within the programmed limits and the validation timer has

expired.

2 REFD fault This bit is 1 if the REFD frequency is outside of the programmed limits.

1 REFD fast This bit is 1 if the REFD frequency is higher than allowed by its profile settings.

(Note that if no REFD input is detected, the REFD fast and slow bits may both be high.)

0 REFD slow This bit is 1 if the REFD frequency is lower than allowed by its profile settings.

AD9554-1 Data Sheet

Rev. C | Page 90 of 99

IRQ MONITOR (REGISTER 0x0D08 TO REGISTER 0x0D16)

If not masked via the IRQ mask registers (Register 0x010F to Register 0x011D), the appropriate IRQ monitor bit is set to Logic 1 when the

indicated event occurs. These bits can be cleared by writing a 1 to the corresponding bit in the IRQ clearing registers (Register 0x0A05 to

Table 114. IRQ Common Functions

Address Bits Bit Name Description

0x0D08 7 SYSCLK unlocked IRQ indicating a SYSCLK PLL state transition from locked to unlocked

6 SYSCLK stable IRQ indicating that SYSCLK stability time has expired and that the SYSCLK PLL is

considered to be stable

5 SYSCLK locked IRQ indicating a SYSCLK PLL state transition from unlocked to locked

4 SYSCLK cal ended IRQ indicating a SYSCLK PLL has ended its calibration

3 SYSCLK cal started IRQ indicating a SYSCLK PLL has started its calibration

2 Watchdog timer IRQ indicating expiration of the watchdog timer

[1:0] Reserved Reserved

0x0D09 7 Reserved Reserved

6 REFB validated IRQ indicating that REFB has been validated

5 REFB fault cleared IRQ indicating that REFB has been cleared of a previous fault

4 REFB fault IRQ indicating that REFB has been faulted

3 Reserved Reserved

2 REFA validated IRQ indicating that REFA has been validated

1 REFA fault cleared IRQ indicating that REFA has been cleared of a previous fault

0 REFA fault IRQ indicating that REFA has been faulted

0x0D0A 7 Reserved Reserved

6 REFD validated IRQ indicating that REFD has been validated

5 REFD fault cleared IRQ indicating that REFD has been cleared of a previous fault

4 REFD fault IRQ indicating that REFD has been faulted

3 Reserved Reserved

2 REFC validated IRQ indicating that REFC has been validated

1 REFC fault cleared IRQ indicating that REFC has been cleared of a previous fault

0 REFC fault IRQ indicating that REFC has been faulted

Data Sheet AD9554-1

Rev. C | Page 91 of 99

Table 115. IRQ Monitor for Digital PLL0 (DPLL_0)

Address Bits Bit Name Description

0x0D0B 7 Frequency unclamped IRQ indicating that DPLL_0 has exited a frequency clamped state

6 Frequency clamped IRQ indicating that DPLL_0 has entered a frequency clamped state

5 Phase slew unlimited IRQ indicating that DPLL_0 has exited a phase slew limited state

4 Phase slew limited IRQ indicating that DPLL_0 has entered a phase slew limited state

3 Frequency unlocked IRQ indicating that DPLL_0 has lost frequency lock

2 Frequency locked IRQ indicating that DPLL_0 has acquired frequency lock

1 Phase unlocked IRQ indicating that DPLL_0 has lost phase lock

0 Phase locked IRQ indicating that DPLL_0 has acquired phase lock

0x0D0C 7 DPLL_0 switching IRQ indicating that DPLL_0 is switching to a new reference

6 DPLL_0 free run IRQ indicating that DPLL_0 has entered free run mode

5 DPLL_0 holdover IRQ indicating that DPLL_0 has entered holdover mode

4 DPLL_0 history updated IRQ indicating that DPLL_0 has updated its tuning word history

3 REFD activated IRQ indicating that DPLL_0 has activated REFD

2 REFC activated IRQ indicating that DPLL_0 has activated REFC

1 REFB activated IRQ indicating that DPLL_0 has activated REFB

0 REFA activated IRQ indicating that DPLL_0 has activated REFA

0x0D0D 7 Phase step direction IRQ indicating that the DPLL_0 demapping controller phase step direction

6 Demap control unclamped IRQ indicating that the DPLL_0 demapping controller is unclamped

5 Demap control clamped IRQ indicating that the DPLL_0 demapping controller is clamped

4 Clock dist sync’d IRQ indicating a distribution sync event

3 APLL_0 unlocked IRQ indicating that APLL_0 has been unlocked

2 APLL_0 locked IRQ indicating that APLL_0 has been locked

1 APLL_0 cal ended IRQ indicating that APLL_0 calibration complete

0 APLL_0 cal started IRQ indicating that APLL_0 calibration started

Table 116. IRQ Monitor for Digital PLL1 (DPLL_1)

Address Bits Bit Name Description

0x0D0E 7 Frequency unclamped IRQ indicating that DPLL_1 has exited a frequency clamped state

6 Frequency clamped IRQ indicating that DPLL_1 has entered a frequency clamped state

5 Phase slew unlimited IRQ indicating that DPLL_1 has exited a phase slew limited state

4 Phase slew limited IRQ indicating that DPLL_1 has entered a phase slew limited state

3 Frequency unlocked IRQ indicating that DPLL_1 has lost frequency lock

2 Frequency locked IRQ indicating that DPLL_1 has acquired frequency lock

1 Phase unlocked IRQ indicating that DPLL_1 has lost phase lock

0 Phase locked IRQ indicating that DPLL_1 has acquired phase lock

0x0D0F 7 DPLL_1 switching IRQ indicating that DPLL_1 is switching to a new reference

6 DPLL_1 free run IRQ indicating that DPLL_1 has entered free run mode

5 DPLL_1 holdover IRQ indicating that DPLL_1 has entered holdover mode

4 DPLL_1 history updated IRQ indicating that DPLL_1 has updated its tuning word history

3 REFD activated IRQ indicating that DPLL_1 has activated REFD

2 REFC activated IRQ indicating that DPLL_1 has activated REFC

1 REFB activated IRQ indicating that DPLL_1 has activated REFB

0 REFA activated IRQ indicating that DPLL_1 has activated REFA

AD9554-1 Data Sheet

Rev. C | Page 92 of 99

Address Bits Bit Name Description

0x0D10 7 Phase step direction IRQ indicating that the DPLL_1 demapping controller phase step direction

6 Demap control unclamped IRQ indicating that the DPLL_1 demapping controller is unclamped

5 Demap control clamped IRQ indicating that the DPLL_1 demapping controller is clamped

4 Clock dist sync’d IRQ indicating a distribution sync event

3 APLL_1 unlocked IRQ indicating that APLL_1 has been unlocked

2 APLL_1 locked IRQ indicating that APLL_1 has been locked

1 APLL_1 cal ended IRQ indicating that APLL_1 calibration complete

0 APLL_1 cal started IRQ indicating that APLL_1 calibration started

Table 117. IRQ Monitor for Digital PLL2 (DPLL_2)

Address Bits Bit Name Description

0x0D11 7 Frequency unclamped IRQ indicating that DPLL_2 has exited a frequency clamped state

6 Frequency clamped IRQ indicating that DPLL_2 has entered a frequency clamped state

5 Phase slew unlimited IRQ indicating that DPLL_2 has exited a phase slew limited state

4 Phase slew limited IRQ indicating that DPLL_2 has entered a phase slew limited state

3 Frequency unlocked IRQ indicating that DPLL_2 has lost frequency lock

2 Frequency locked IRQ indicating that DPLL_2 has acquired frequency lock

1 Phase unlocked IRQ indicating that DPLL_2 has lost phase lock

0 Phase locked IRQ indicating that DPLL_2 has acquired phase lock

0x0D12 7 DPLL_2 switching IRQ indicating that DPLL_2 is switching to a new reference

6 DPLL_2 free run IRQ indicating that DPLL_2 has entered free run mode

5 DPLL_2 holdover IRQ indicating that DPLL_2 has entered holdover mode

4 DPLL_2 history updated IRQ indicating that DPLL_2 has updated its tuning word history

3 REFD activated IRQ indicating that DPLL_2 has activated REFD

2 REFC activated IRQ indicating that DPLL_2 has activated REFC

1 REFB activated IRQ indicating that DPLL_2 has activated REFB

0 REFA activated IRQ indicating that DPLL_2 has activated REFA

0x0D13 7 Phase step direction IRQ indicating that the DPLL_2 demapping controller phase step direction

6 Demap control unclamped IRQ indicating that the DPLL_2 demapping controller is unclamped

5 Demap control clamped IRQ indicating that the DPLL_2 demapping controller is clamped

4 Clock dist sync’d IRQ indicating a distribution sync event

3 APLL_2 unlocked IRQ indicating that APLL_2 has been unlocked

2 APLL_2 locked IRQ indicating that APLL_2 has been locked

1 APLL_2 cal ended IRQ indicating that APLL_2 calibration complete

0 APLL_2 cal started IRQ indicating that APLL_2 calibration started

Data Sheet AD9554-1

Rev. C | Page 93 of 99

Table 118. IRQ Monitor for Digital PLL3 (DPLL_3)

Address Bits Bit Name Description

0x0D14 7 Frequency unclamped IRQ indicating that DPLL_3 has exited a frequency clamped state

6 Frequency clamped IRQ indicating that DPLL_3 has entered a frequency clamped state

5 Phase slew unlimited IRQ indicating that DPLL_3 has exited a phase slew limited state

4 Phase slew limited IRQ indicating that DPLL_3 has entered a phase slew limited state

3 Frequency unlocked IRQ indicating that DPLL_3 has lost frequency lock

2 Frequency locked IRQ indicating that DPLL_3 has acquired frequency lock

1 Phase unlocked IRQ indicating that DPLL_3 has lost phase lock

0 Phase locked IRQ indicating that DPLL_3 has acquired phase lock

0x0D15 7 DPLL_3 switching IRQ indicating that DPLL_3 is switching to a new reference

6 DPLL_3 free run IRQ indicating that DPLL_3 has entered free run mode

5 DPLL_3 holdover IRQ indicating that DPLL_3 has entered holdover mode

4 DPLL_3 history updated IRQ indicating that DPLL_3 has updated its tuning word history

3 REFD activated IRQ indicating that DPLL_3 has activated REFD

2 REFC activated IRQ indicating that DPLL_3 has activated REFC

1 REFB activated IRQ indicating that DPLL_3 has activated REFB

0 REFA activated IRQ indicating that DPLL_3 has activated REFA

0x0D16 7 Phase step direction IRQ indicating that the DPLL_3 demapping controller phase step direction

6 Demap control unclamped IRQ indicating that the DPLL_3 demapping controller is unclamped

5 Demap control clamped IRQ indicating that the DPLL_3 demapping controller is clamped

4 Clock dist sync’d IRQ indicating a distribution sync event

3 APLL_3 unlocked IRQ indicating that APLL_3 has been unlocked

2 APLL_3 locked IRQ indicating that APLL_3 has been locked

1 APLL_3 cal ended IRQ indicating that APLL_3 calibration complete

0 APLL_3 cal started IRQ indicating that APLL_3 calibration started

PLL_0 READ ONLY STATUS (REGISTER 0x0D20 TO REGISTER 0x0D2A)

All bits in Register 0x0D20 to Register 0x0D2A are read only. To report the latest status, these bits require an IO_UPDATE

(Register 0x000F = 0x01) immediately before being read.

Table 119. PLL_0 Lock Status

Address Bits Bit Name Description

0x0D20 [7:5] Reserved Default: 000b.

4 APLL_0 cal in progress The control logic holds this bit set while the calibration of the APLL_0 VCO is in progress.

3 APLL_0 frequency lock Indicates the status of APLL_0.

0 = unlocked.

1 = locked.

2 DPLL_0 frequency lock Indicates the frequency lock status of DPLL_0.

0 = unlocked.

1 = locked.

1 DPLL_0 phase lock Indicates the phase lock status of DPLL_0.

0 = unlocked.

1 = locked.

0 PLL_0 all locked Indicates the status of the system clock, APLL_0, and DPLL_0.

0 = system clock PLL, APLL_0, or DPLL_0 is unlocked.

1 = all three PLLs (system clock PLL, APLL_0, and DPLL_0) are locked.

AD9554-1 Data Sheet

Rev. C | Page 94 of 99

Table 120. DPLL_0 Loop State

Address Bits Bit Name Description

0x0D21 [7:5] Reserved Default: 000b.

[4:3] DPLL_0 active ref Indicates the reference input that DPLL_0 is using.

00 = DPLL_0 has selected REFA.

01 = DPLL_0 has selected REFB.

10 = DPLL_0 has selected REFC.

11 = DPLL_0 has selected REFD.

2 DPLL_0 switching Indicates that DPLL_0 is switching input references.

0 = DPLL is not switching.

1 = DPLL is switching input references.

1 DPLL_0 holdover Indicates that DPLL_0 is in holdover mode.

0 = not in holdover.

1 = in holdover mode.

0 DPLL_0 free run Indicates that DPLL_0 is in free run mode.

0 = not in free run mode.

1 = in free run mode.

0x0D22 [7:4] Reserved Default: 00000b.

3 Demap controller clamped The control logic sets this bit when DPLL_0 demapping controller is clamped.

2 DPLL_0 phase slew limited The control logic sets this bit when DPLL_0 is phase slew limited.

1 DPLL_0 frequency clamped The control logic sets this bit when DPLL_0 is frequency clamped.

0 DPLL_0 history available

The control logic sets this bit when the tuning word history of DPLL_0 is available.

(See Register 0x0D23 to Register 0x0D26 for the tuning word.)

Table 121. DPLL_0 Holdover History

Address Bits Bit Name Description

0x0D23 [7:0]

DPLL_0 tuning word

readback, Bits[23:0]

DPLL_0 tuning word readback bits, Bits[7:0]. This group of registers contains the

averaged digital PLL tuning word used when the DPLL enters holdover. Setting the

history accumulation timer to its minimal value allows the user to use these registers for

a read back of the most recent DPLL tuning word with only 1 ms of averaging.

Instantaneous tuning word readback is not available.

0x0D24 [7:0] DPLL_0 tuning word readback, Bits[15:8].

0x0D25 [7:0] DPLL_0 tuning word readback, Bits[23:16].

0x0D26 [7:6] Reserved Reserved.

[5:0] DPLL_0 tuning word

readback, Bits[29:24]

DPLL_0 tuning word readback, Bits[29:24].

Table 122. DPLL_0 Phase Lock and Frequency Lock Bucket Levels

Address Bits Bit Name Description

0x0D27 [7:0]

DPLL_0 phase lock detect

bucket level

Read only digital PLL lock detect bucket level, Bits[7:0]; see the DPLL Frequency Lock

Detector section for details.

0x0D28 [7:4] Reserved Reserved.

[3:0]

DPLL_0 phase lock detect

bucket level

Read only digital PLL lock detect bucket level, Bits[11:8]; see the DPLL Frequency Lock

Detector section for details.

0x0D29 [7:0]

DPLL_0 frequency lock

detect bucket level

Read only digital PLL lock detect bucket level, Bits[7:0]; see the DPLL Phase Lock Detector

section for details.

0x0D2A [7:4] Reserved Reserved.

[3:0]

DPLL_0 frequency lock

detect bucket level

Read only digital PLL lock detect bucket level, Bits[11:8]; see the DPLL Phase Lock

Detector section for details.

Data Sheet AD9554-1

Rev. C | Page 95 of 99

PLL_1 READ ONLY STATUS (REGISTER 0x0D40 TO REGISTER 0x0D4A)

These registers mimic the PLL_0 control registers (Register 0x0D20 through Register 0x0D2A) but the register addresses are offset by

0x0020. All default values are identical. All bits in Register 0x0D40 to Register 0x0D4A are read only. To report the latest status, these bits

require an IO_UPDATE (Register 0x000F = 0x01) immediately before being read.

PLL_2 READ ONLY STATUS (REGISTER 0x0D60 TO REGISTER 0x0D6A)

These registers mimic the PLL_0 control registers (Register 0x0D20 through Register 0x0D2A) but the register addresses are offset by

0x0040. All bits in Register 0x0D60 to Register 0x0D6A are read only. To report the latest status, these bits require an IO_UPDATE

(Register 0x000F = 0x01) immediately before being read.

PLL_3 READ ONLY STATUS (REGISTER 0x0D80 TO REGISTER 0x0D8A)

These registers mimic the PLL_0 control registers (Register 0x0D20 through Register 0x0D2A) but the register addresses are offset by

0x0060. All bits in Register 0x0D40 to Register 0x0D4A are read only. To report the latest status, these bits require an IO_UPDATE

(Register 0x000F = 0x01) immediately before being read.

Table 123. Multifunction Pin Output Functions (D7 = 1)

Bits[D7:D0] Value Output Function Source Proxy

0x80 Static Logic 0 None

0x81 Static Logic 1 None

0x82 System clock divided by 32 None

0x83 Watchdog timer output; this is a strobe whose duration equals

(32/(one system clock period)) when timer expires

None

0x84 SYSCLK PLL calibration busy Register 0x0D01, Bit 2

0x85 SYSCLK PLL lock detected Register 0x0D01, Bit 0

0x86 SYSCLK PLL stable Register 0x0D01, Bit 1

0x87 All PLLs locked (logical AND of 0x88, 0x89, 0x8A, 0x8B) Register 0x0D01, Bits[7:4]

0x88 (DPLL_0 phase lock) AND (APLL_0 lock) AND (SYSCLK PLL lock) Register 0x0D01, Bit 4

0x89 (DPLL_1 phase lock) AND (APLL_1 lock) AND (SYSCLK PLL lock) Register 0x0D01, Bit 5

0x8A (DPLL_2 phase lock) AND (APLL_2 lock) AND (SYSCLK PLL lock) Register 0x0D01, Bit 6

0x8B (DPLL_3 phase lock) AND (APLL_3 lock) AND (SYSCLK PLL lock) Register 0x0D01, Bit 7

0x8C Unused

0x8D Unused

0x8E Unused

0x90 All IRQs: (IRQ_common) OR (IRQ_PLL_0) OR (IRQ_PLL_1) OR

(IRQ_PLL_2) OR (IRQ_PLL_3)

None

0x91 IRQ_common None

0x92/0x93/0x94/0x95 IRQ_PLL_0/IRQ_PLL_1/IRQ_PLL_2/IRQ_PLL_3 None

0xA0/0xA1/0xA2/0xA3 REFA/REFB/REFC/REFD fault Register 0x0D02/Register 0x0D03/

0xA8/0xA9/0xAA/0xAB REFA/REFB/REFC/REFD valid Register 0x0D02/Register 0x0D03/

0xB0 REFA active (any PLL) Register 0x0D02, Bit 4||Bit 5||Bit 6||Bit 7

0xB1 REFB active (any PLL) Register 0x0D03, Bit 4||Bit 5||Bit 6||Bit 7

0xB2 REFC active (any PLL) Register 0x0D04, Bit 4||Bit 5||Bit 6||Bit 7

0xB3 REFD active (any PLL) Register 0x0D05, Bit 4||Bit 5||Bit 6||Bit 7

0xC0 DPLL_0 phase locked Register 0x0D20, Bit 1

0xC1 DPLL_0 frequency locked Register 0x0D20, Bit 2

0xC2 APLL_0 frequency lock Register 0x0D20, Bit 3

0xC3 APLL_0 cal in process Register 0x0D20, Bit 4

0xC4 DPLL_0 active Logical OR of Bit 4 in Register 0x0D02

through Register 0x0D05

0xC5 DPLL_0 in free run mode Register 0x0D21, Bit 0

0xC6 DPLL_0 in holdover Register 0x0D21, Bit 1

0xC7 DPLL_0 switching Register 0x0D21, Bit 2

0xC8 DPLL_0 history available Register 0x0D22, Bit 0

0xC9 DPLL_0 history updated Register 0x0D0C, Bit 4 (IRQ does not

need to be set for this setting to work)

AD9554-1 Data Sheet

Rev. C | Page 96 of 99

Bits[D7:D0] Value Output Function Source Proxy

0xCA DPLL_0 clamp Register 0x0D22, Bit 1

0xCB DPLL_0 phase slew limited Register 0x0D22, Bit 2

0xCC PLL_0 clock distribution sync pulse None

0xCD DPLL_1 demapping controller clamped Register 0x0D22, Bit 3

0xD0 DPLL_1 phase locked Register 0x0D40, Bit 1

0xD1 DPLL_1 frequency locked Register 0x0D40, Bit 2

0xD2 APLL_1 frequency lock Register 0x0D40, Bit 3

0xD3 APLL_1 cal in process Register 0x0D40, Bit 4

0xD4 DPLL_1 active Logical OR of Bit 5 in Register 0x0D02

through Register 0x0D05

0xD5 DPLL_1 in free run mode Register 0x0D41, Bit 0

0xD6 DPLL_1 in holdover Register 0x0D41, Bit 1

0xD7 DPLL_1 in switchover Register 0x0D41, Bit 2

0xD8 DPLL_1 history available Register 0x0D42, Bit 0

0xD9 DPLL_1 history updated Register 0x0D0F, Bit 4 (IRQ does not

need to be set for this setting to work)

0xDA DPLL_1 clamp Register 0x0D42, Bit 1

0xDB DPLL_1 phase slew limited Register 0x0D42, Bit 2

0xDC PLL_1 clock distribution sync pulse None

0xDD DPLL_1 demapping controller clamped Register 0x0D42, Bit 3

0xE0 DPLL_2 phase locked Register 0x0D60, Bit 1

0xE1 DPLL_2 frequency locked Register 0x0D60, Bit 2

0xE2 APLL_2 frequency lock Register 0x0D60, Bit 3

0xE3 APLL_2 cal in process Register 0x0D60, Bit 4

0xE4 DPLL_2 active Logical OR of Bit 6 in Register 0x0D02

through Register 0x0D05

0xE5 DPLL_2 in free run mode Register 0x0D61, Bit 0

0xE6 DPLL_2 in holdover Register 0x0D61, Bit 1

0xE7 DPLL_2 switching Register 0x0D61, Bit 2

0xE8 DPLL_2 history available Register 0x0D62, Bit 0

0xE9 DPLL_2 history update Register 0x0D0C, Bit 4 (IRQ does not

need to be set for this setting to work)

0xEA DPLL_2 clamp Register 0x0D62, Bit 1

0xEB DPLL_2 phase slew limited Register 0x0D62, Bit 2

0xEC PLL_2 clock distribution sync pulse None

0xED DPLL_2 demapping controller clamped Register 0x0D62, Bit 4

0xF0 DPLL_3 phase locked Register 0x0D80, Bit 1

0xF1 DPLL_3 frequency locked Register 0x0D80, Bit 2

0xF2 APLL_3 frequency lock Register 0x0D80, Bit 3

0xF3 APLL_3 cal in process Register 0x0D80, Bit 4

0xF4 DPLL_3 active Logical OR of Bit 7 in Register 0x0D02

through Register 0x0D05

0xF5 DPLL_3 in free run mode Register 0x0D81, Bit 0

0xF6 DPLL_3 in holdover Register 0x0D81, Bit 1

0xF7 DPLL_3 switching Register 0x0D81, Bit 2

0xF8 DPLL_3 history available Register 0x0D82, Bit 0

0xF9 DPLL_3 history update Register 0x0D0F, Bit 4 (IRQ does not

need to be set for this setting to work)

0xFA DPLL_3 clamp Register 0x0D82, Bit 1

0xFB DPLL_3 phase slew limited Register 0x0D82, Bit 2

0xFC PLL_3 clock distribution sync pulse None

0xFD DPLL_3 demapping controller clamped Register 0x0D82, Bit 3

0xFE to 0xFF Reserved None

Data Sheet AD9554-1

Rev. C | Page 97 of 99

Table 124. Multifunction Pin Input Functions (D7 = 0)

Bits[D7:D0] Value Input Function Destination Proxy

0x00 No function None

0x01 IO_UPDATE Register 0x000F, Bit 0

0x02 Full power-down Register 0x0A00, Bit 0

0x03 Clear watchdog timer Register 0x0A05, Bit 7

0x04 Soft sync all Register 0x0A00, Bit 3

0x10 Clear all IRQs Register 0x0A05, Bit 0

0x11 Clear common IRQs Register 0x0A05, Bit 1

0x12 Clear DPLL_0 IRQs Register 0x0A05, Bit 2

0x13 Clear DPLL_1 IRQs Register 0x0A05, Bit 3

0x14 Clear DPLL_2 IRQs Register 0x0A05, Bit 4

0x15 Clear DPLL_3 IRQs Register 0x0A05, Bit 5

0x20/0x21/0x22/0x23 Force fault REFA/REFB/REFC/REFD Register 0x0A03, Bits[3:0]

0x28/0x29/0x2A/0x2B Force validation timeout REFA/REFB/REFC/REFD Register 0x0A02, Bits[3:0]

0x40 PLL_0 power-down Register 0x0A20, Bit 0

0x41 DPLL_0 user free run Register 0x0A22, Bit 0

0x42 DPLL_0 user holdover Register 0x0A22, Bit 1

0x43 DPLL_0 tuning word history reset Register 0x0A23, Bit 1

0x44 DPLL_0 increment phase offset Register 0x0A24, Bit 0

0x45 DPLL_0 decrement phase offset Register 0x0A24, Bit 1

0x46 DPLL_0 reset phase offset Register 0x0A24, Bit 2

0x48 APLL_0 soft sync Register 0x0A20, Bit 2

0x49 PLL_0 disable OUT0B Register 0x0A21, Bit 2

0x4A Unused

0x4B PLL_0 disable OUT0B Register 0x0A21, Bit 3

0x4C PLL_0 manual reference input selection, Bit 0 Register 0x0A22, Bit 5

0x4D PLL_0 manual reference input selection, Bit 1 Register 0x0A22, Bit 6

0x50 PLL_1 power-down Register 0x0A40, Bit 0

0x51 DPLL_1 user free run Register 0x0A42, Bit 0

0x52 DPLL_1 user holdover Register 0x0A42, Bit 1

0x53 DPLL_1 tuning word history reset Register 0x0A43, Bit 1

0x54 DPLL_1 increment phase offset Register 0x0A44, Bit 0

0x55 DPLL_1 decrement phase offset Register 0x0A44, Bit 1

0x56 DPLL_1 reset phase offset Register 0x0A44, Bit 2

0x58 APLL_1 soft sync Register 0x0A40, Bit 2

0x59 PLL_1 disable OUT1B Register 0x0A41, Bit 2

0x5A Unused

0x5B PLL_1 disable OUT1B Register 0x0A41, Bit 3

0x5C PLL_1 manual reference input selection, Bit 0 Register 0x0A42, Bit 5

0x5D PLL_1 manual reference input selection, Bit 1 Register 0x0A42, Bit 6

0x60 PLL_2 power-down Register 0x0A60, Bit 0

0x61 DPLL_2 user free run Register 0x0A62, Bit 0

0x62 DPLL_2 user holdover Register 0x0A62, Bit 1

0x63 DPLL_2 tuning word history reset Register 0x0A63, Bit 1

0x64 DPLL_2 increment phase offset Register 0x0A64, Bit 0

0x65 DPLL_2 decrement phase offset Register 0x0A64, Bit 1

0x66 DPLL_2 reset phase offset Register 0x0A64, Bit 2

0x68 APLL_2 soft sync Register 0x0A60, Bit 2

0x69 PLL_2 disable OUT2B Register 0x0A61, Bit 2

0x6A Unused

0x6B PLL_2 disable OUT2B Register 0x0A61, Bit 3

0x6C PLL_2 manual reference input selection, Bit 0 Register 0x0A62, Bit 5

0x6D PLL_2 manual reference input selection, Bit 1 Register 0x0A62, Bit 6

AD9554-1 Data Sheet

Rev. C | Page 98 of 99

Bits[D7:D0] Value Input Function Destination Proxy

0x70 PLL_2 power-down Register 0x0A60, Bit 0

0x71 DPLL_3 user free run Register 0x0A82, Bit 0

0x72 DPLL_3 user holdover Register 0x0A82, Bit 1

0x73 DPLL_3 tuning word history reset Register 0x0A83, Bit 1

0x74 DPLL_3 increment phase offset Register 0x0A84, Bit 0

0x75 DPLL_3 decrement phase offset Register 0x0A84, Bit 1

0x76 DPLL_3 reset phase offset Register 0x0A84, Bit 2

0x78 APLL_3 soft sync Register 0x0A80, Bit 2

0x79 PLL_3 disable OUT3B Register 0x0A81, Bit 2

0x7A Unused

0x7B PLL_3 disable OUT3B Register 0x0A81, Bit 3

0x7C PLL_3 manual reference input selection, Bit 0 Register 0x0A82, Bit 5

0x7D PLL_3 manual reference input selection, Bit 1 Register 0x0A82, Bit 6

0x7E to 0x7F Reserved None

Data Sheet AD9554-1

Rev. C | Page 99 of 99

OUTLINE DIMENSIONS

0.50

BSC

PIN 1

INDICATOR

*6.50

6.40 SQ

6.30

0.45

0.40

0.35

0.80

0.75

0.70 0.0 5 MAX

0.02 N OM

0.20 3 RE F

COPLANARITY

0.08

0.30

0.25

0.18

8.10

8.00 SQ

7.90

0.20 MI N

6.50 RE F

*COM PLI ANT TO JEDE C STANDARDS MO - 220 -W LL D- 5

WIT H EXCEPTION TO EXPOSED PAD DIMENSION.

TOP VIEW BOTTOM VIEW

EXPOSED

PAD

PKG-005610

03-08-2017-A

FOR PROPER CONNECTI ON O F

THE EXPOSED PAD, REFER TO

THE P IN CO NFI GURATION AND

FUNCTION DE S CRIPTIONS

SECTION OF THIS DATA SHEET.

PIN 1

INDICATOR AREA OPTIONS

(SEE DETAIL A)

DETAIL A

(J EDEC 95 )

SEATING

PLANE

Figure 47. 56-Lead Lead Frame Chip Scale Package [LFCSP]

8 mm × 8 mm Body and 0.75 mm Package Height

(CP-56-10)

Dimensions shown in millimeters

ORDERING GUIDE

Model1 Temperature Range Package Description Package Option

AD9554-1BCPZ −40°C to +85°C 56-Lead Lead Frame Chip Scale Package [LFCSP] CP-56-10

AD9554-1BCPZ-REEL7 −40°C to +85°C 56-Lead Lead Frame Chip Scale Package [LFCSP] CP-56-10

AD9554-1/PCBZ Evaluation Board

1 Z = RoHS Compliant Part.

I2C refers to a communications protocol originally developed by Philips Semiconductors (now NXP Semiconductors).

registered trademarks are the property of their respective owners.

D12214-0-3/17(C)