1 of 18 032002
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FEATURES
Direct replacement for LXP610SE
Converts E-carrier clock rates to T-carrier
clock rates
Converts T-carrier clock rates to E-carrier
clock rates
Low jitter output
Multiple output clocks synchronized to input
clock
8kHz frequency-locked output for all modes
of operation
No external components required
16-pin SO and 28-pin PLCC
Industrial temperature range: -40ºC to +85ºC
ORDERING INFORMATION
DS21610SN 16-pin SO -40°C to +85°C
DS21610QN 28-pin PLCC -40°C to +85°C
DESCRIPTION
The DS21610 is a multirate, low-jitter clock adapter that converts E-carrier and T-carrier clocks to
multiple PDH carrier clock rates. Two clock outputs are available that are frequency-locked to the input
clock. The clock outputs along with an 8kHz frame-sync output can be phase-aligned to a frame-sync
input. The device is backward compatible with the LXP610 and operates from a single 5V supply. All
modes of operation include a standard 8kHz output.
DALLAS
DS21610
DS21610
Clock Rate Adapte
r
www.maxim-ic.com
DS21610
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TABLE OF CONTENTS
1. FUNCTIONAL DESCRIPTION....................................................................................4
1.1 PIN FUNCTION DESCRIPTION.............................................................................................................5
1.2 COMPATIBLITY W ITH LXP610..........................................................................................................7
2. OPERATION...................................................................................................................8
3. JITTER SPECIFICATIONS..........................................................................................9
4. OPERATING PARAMETERS....................................................................................11
4.1 TIMING ...........................................................................................................................................12
5. PACKAGE SPECIFICATIONS.................................................................................16
6. REVISION HISTORY.................................................................................................18
DS21610
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LIST OF FIGURES
Figure 1-1 DS21610 BLOCK DIAGRAM...................................................................................................4
Figure 3-1 NOMINAL JITTER TRANSFER (1.544MHz CLKIN to 2.048MHz CLKOUT1)...................9
Figure 3-2 NOMINAL JITTER TRANSFER (2.048MHz CLKIN to 1.544MHz CLKOUT1).................10
Figure 4-1 AC TIMING DIAGRAMS........................................................................................................13
Figure 5-1 PACKAGE OUTLINE 16 PIN SO 0.300" BODY...................................................................16
LIST OF TABLES
Table 1-1 PIN DESCRIPTION SORTED BY PIN NUMBER....................................................................6
Table 1-2 PIN NAME CROSS REFERENCE TO LXP610.........................................................................7
Table 2-1 PROGRAM PIN FUNCTIONS (SEL = 0)...................................................................................8
Table 2-2 PROGRAM PIN FUNCTIONS (SEL = 1)...................................................................................8
Table 3-1 OUTPUT JITTER SPECIFICATIONS, CLKOUT1 = 1.544MHz..............................................9
Table 3-2 OUTPUT JITTER SPECIFICATIONS, CLKOUT1 = 2.048MHz..............................................9
Table 4-1 AC TIMING ...............................................................................................................................12
DS21610
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1. FUNCTIONAL DESCRIPTION
A clock input at CLKIN is converted to various clocks available on CLKOUT1 and CLKOUT2.
Additionally, an 8kHz clock locked to CLKIN and SYNCIN (if present) is always available at the
SYNCOUT pin. The pulse width of the SYNCOUT is selectable. It can be one or one-half the clock
period of CLKIN, centered on the rising edge of CLKIN. Pins P1 to P4 are used to select the various
clock rates and operational modes. Table 2-1 and Table 2-2 list the various operational modes of the
DS21610.
CLKIN, CLKOUT1, and CLCKOUT2 are always frequency-locked. They can all be phase-locked to a
system frame-sync pulse. A fram e-s ync pulse applied to SYNC IN will cause CLKIN and C LKOUT1 and
CLKOUT2 to be phased-locked to that sync pulse. This will cause the clocks to have a fixed alignment at
the frame-sync boundaries. The signal applied to SYNCIN can be 8kHz or some integer subrate such as
1kHz, 2kHz, or 4kHz. Phase synchronization will occur within a maximum of 50ms when SYNCIN is
8kHz.
Figure 1-1. DS21610 BLOCK DIAGRAM
ANALOG
PLL
OUTPUT
DIVIDER
FRAME SYNC
GENERATOR
CLKIN
SEL
SYNCIN
CLKOUT2
CLKOUT1
SYNCOUT
FEEDBACK
CIRCUIT
FREQUENCY
PLL
SELECT
LOGIC
P1
P2
P3
P4
FSP
DS21610
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1.1 PIN FUNCTION DESCRIPTION
Signal Name: CLKIN
Signal Description: Clock Input
Signal Type: Input
Reference Clock Input. CLKOUT1 and CLKOUT2 will be referenced to this clock.
Signal Name: CLKOUT1
Signal Description: Clock Output 1
Signal Type: Output
T1 or E1 carrier clock output referenced to CLKIN.
Signal Name: CLKOUT2
Signal Description: Clock Output 2
Signal Type: Output
T1 or E1 carrier clock output referenced to CLKIN.
Signal Name: P1 to P4
Signal Description: Program Pins 1 to 4
Signal Type: Input
Used to select the various combinations of clock and sync outputs.
Signal Name: SEL
Signal Description: Clock Mode Select
Signal Type: Output
T-carrier/E-carrier mode select.
Signal Name: SYNCIN
Signal Description: Synchronization Input
Signal Type: Input
Used to synchronize the clock outputs and SYNCOUT to CLKIN and SYNCIN. SYNCIN should be tied
high or low when not in use.
Signal Name: SYNCOUT
Signal Description: Synchronization Output
Signal Type: Output
An 8kHz output that will be synchronized to the clock outputs and SYNCIN (if present).
Signal Name: FSP
Signal Description: Frame Synchronization Pulse Polarity
Signal Type: Input
Used to change the polarity of the SYNCOUT output.
Signal Name: VDD
Signal Description: Positive Supply
Signal Type: Supply
5V ±5%
Signal Name: Vss
Signal Description: Signal Ground
Signal Type: Supply
Ground
DS21610
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Table 1-1. PIN DESCRIPTION SORTED BY PIN NUMBER
28-PIN PLCC
PIN NO. 16-PIN SO
PIN NO. PIN NAME TYPE DESCRIPTION
1 1 P3 I Program Pin 3
2 2 SYNCOUT O Synchronization Pulse Output
3 3 N/C - NO CONNECT
4 - N/C - NO CONNECT
5 - N/C - NO CONNECT
6 4 CLKOUT2 O Clock 2 Output
7 - N/C - NO CONNECT
8 - N/C - NO CONNECT
9 - N/C - NO CONNECT
10 5 CLKIN I Clock Input
11 6 N/C - NO CONNECT
12 - N/C - NO CONNECT
13 7 CLKOUT1 O Clock 1 Output
14 8 P1 I Program Pin 1
15 9 VSS - Ground
16 10 P2 I Program Pin 2
17 - N/C - NO CONNECT
18 - N/C - NO CONNECT
19 11 N/C - NO CONNECT
20 12 SEL I Clock Mode Select
21 - N/C - NO CONNECT
22 13 FSP I Frame Sync Polarity
23 - N/C - NO CONNECT
24 14 SYNCIN I Synchronization Pulse Input
25 - N/C - NO CONNECT
26 - N/C - NO CONNECT
27 15 P4 I Program Pin 4
28 16 VDD - Positive Supply
DS21610
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1.2 COMPATIBLITY WITH LXP610
The DS21610 is pin-compatible with the LXP610.
Table 1-2. PIN NAME CROSS-REFERENCE TO LXP610
DS21610
PIN NAME LXP610
PIN NAME DESCRIPTION
P3 P3 Program Pin 3
SYNCOUT FSO Synchronization Pulse Output
CLKOUT2 HFO Clock 2 Output
CLKIN CLKI Clock Input
CLKOUT1 CLKO Clock 1 Output
P1 P1 Program pin 1
VSS GND Ground
P2 P2 Program Pin 2
N/C N/C NO CONNECT
SEL SEL Clock Mode Select
FSP FSP Frame Sync Polarity
SYNCIN FSI Synchronization Pulse Input
P4 P4 Program Pin 4
VDD V
CC Positive Supply
DS21610
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2. OPERATION
Table 2-1. PROGRAM PIN FUNCTIONS (SEL = 0)
P4 P3 P2 P1 CLKIN CLKOUT1 CLKOUT2 SYNCOUT
0 0 0 0 1.544 2.048 6.144 LONG
0 0 0 1 3.088 2.048 8.192 SHORT
0 0 1 0 1.544 2.048 6.144 LONG
0 0 1 1 1.544 2.048 8.192 SHORT
0 1 0 0 1.544 2.560 7.680 LONG
0 1 0 1 6.176 4.096 8.192 LONG
0 1 1 0 1.544 2.560 7.680 LONG
0 1 1 1 6.176 2.048 8.192 SHORT
1 0 0 0 3.088 2.048 6.144 LONG
1 0 0 1 3.088 4.096 8.192 LONG
1 0 1 0 3.088 2.048 6.144 LONG
1 0 1 1 1.544 4.096 8.192 LONG
1 1 0 0 6.176 2.560 7.680 LONG
1 1 0 1 6.176 4.096 8.192 LONG
1 1 1 0 6.176 2.560 7.680 LONG
1 1 1 1 6.176 4.096 8.192 LONG
Table 2-2. PROGRAM PIN FUNCTIONS (SEL = 1)
P4 P3 P2 P1 CLKIN CLKOUT1 CLKOUT2 SYNCOUT
0 0 0 0 2.048 3.088 6.176 LONG
0 0 0 1 2.048 3.088 6.176 LONG
0 0 1 0 2.048 1.544 6.176 LONG
0 0 1 1 2.048 1.544 6.176 LONG
0 1 0 0 2.560 1.544 7.720 LONG
0 1 0 1 8.192 3.088 6.176 LONG
0 1 1 0 2.560 1.544 7.720 LONG
0 1 1 1 8.192 1.544 6.176 LONG
1 0 0 0 2.048 3.088 6.176 LONG
1 0 0 1 4.096 3.088 6.176 LONG
1 0 1 0 2.048 3.088 6.176 LONG
1 0 1 1 4.096 1.544 6.176 LONG
1 1 0 0 2.560 1.544 7.720 LONG
1 1 0 1 8.192 3.088 6.176 LONG
1 1 1 0 2.560 1.544 7.720 LONG
1 1 1 1 8.192 1.544 6.176 LONG
DS21610
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3. JITTER SPECIFICATIONS
Table 3-1. OUTPUT JITTER SPECIFICATIONS, CLKOUT1 = 1.544MHz
FREQUENCY BAND TR62411 SPECIFICATION TYP MAX UNIT
No Bandlimiting 0.050 0.010 0.020 UIpp
10Hz to 40kHz 0.025 0.005 0.010 UIpp
8kHz to 40kHz 0.025 0.004 0.012 UIpp
Note: CLKIN = 2.048MHz OR 4.096MHz
Table 3-2. OUTPUT JITTER SPECIFICATIONS, CLKOUT1 = 2.048MHz
FREQUENCY BAND G.823 SPECIFICATION TYP MAX UNIT
20Hz to 100kHz 1.5 0.018 0.035 UIpp
18kHz to 100kHz 0.2 0.012 0.025 UIpp
Note: CLKIN = 1.544MHz
Figure 3-1. NOMINAL JITTER TRANSFER (1.544MHz CLKIN to 2.048MHz
CLKOUT1)
Note: The typical peak jitter gain of DS21610 is about 1.6 for conversion from T1 to E1. The typical
peak jitter gain of the Level One device is about 1.1. However, the jitter gain for the DS21610 device
peaks in the 4kHz to 8kHz range, whereas the peak jitter gain for the LXP610 device spans a greater
frequency range (20kHz to 40kHz).
0.00
0.20
0.40
0.60
0.80
1.00
1.20
1.40
1.60
1.80
2.00
0 5 10 15 20 25 30 35 40
Jitter Frequency (kHz)
Jitter Gain (ns/ns)
DS21610
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Figure 3-2. NOMINAL JITTER TRANSFER (2.048MHz CLKIN to 1.544MHz
CLKOUT1)
Note: The typical peak jitter gain of DS21610 is about 1.4 for conversion from E1 to T1. The typical
peak jitter gain of the Level One device is about 1.1. However, the jitter gain for the DS21610 device
peaks in the 4kHz to 8kHz range whereas the peak jitter gain for the LXP610 device spans a greater
frequency range (20kHz to 40kHz).
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
2
0 1020304050607080
Jitter Frequency (kHz)
DS21610
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4. OPERATING PARAMETERS
ABSOLUTE MAXIMUM RATINGS*
Voltage Range on Any Pin Relative to Ground -1.0V to +6.0V
Operating Temperature Range for DS21610SN -40°C to +85°C
Storage Temper ature Ra nge -55°C to +125°C
* This is a stress rating only and functional operation of the device at these or any other conditions
beyond those indicated in the operation sections of this specification is not implied. Exposure to
absolute maximum rating conditions for extended periods of time can affect reliability.
RECOMMENDED DC OPERATING CONDITIONS (-40°C to +85°C)
PARAMETER SYMBOL MIN TYP MAX UNITS NOTES
Logic 1 VIH 2.0 5.5 V
Logic 0 VIL -0.3 +0.8 V
Supply for 5V Operation VDD 4.75 5 5.25 V
DC CHARACTERISTICS (-40°C to +85°C; VDD = 5.0V ± 5%)
PARAMETER SYMBOL MIN TYP MAX UNITS NOTES
Supply Current at 5V IDD 14 mA 2
Input Leakage IIL -10.0 +10.0 µA 1
Output Current (2.4V) IOH -1.0 mA
Output Current (0.4V) IOL +4.0 mA
NOTES:
1) 0.0V < VIN < VDD.
2) 100pF load on all outputs.
DS21610
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4.1 AC TIMING
PARAMETER SYMBOL MIN TYP MAX UNITS
Capture Range on CLKIN1 ±10000 - - ppm
Lock Range on CLKIN1 ±10000 - - ppm
CLKIN Duty Cycle1 35 - 65 %
SYNCIN Setup to CLKIN Rising tSU 46 - - ns
SYNCIN Hold after CLKIN Rising tHI 30 - - ns
SYNCIN Pulse Width tPW 76
CLKIN
period ns
CLKOUT1 Delay from CLKIN
Rising tD -15 0 +15 ns
CLKOUT1 Duty Cycle CD 50 %
SYNCOUT Delay from CLKOUT2 tDF -5 - 30 ns
SYNCOUT Pulse Width (Low) tSPW -
CLKOUT1
Period ns
CLKOUT1 Delay from CLKOUT2
Rising tDH -15 0 +15 ns
Rise/Fall Time on CLKIN,
SYNCIN1 tRF - - 40 ns
Rise/Fall Time on CLKOUT,
SYNCOUT, CLKOUT2 with a
25pF Load tRF - - 40 ns
1. Guaranteed by design
DS21610
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Figure 4-1. AC TIMING DIAGRAMS
SYNCIN/CLKIN to CLKOUT1/SYNCOUT and CLKOUT2
SYNCOUT
CLKOUT1
tDH
CLKOUT1
CLKOUT2
tDH
tD
tPW
tHI tSU
SINCIN
CLKIN
CLKOUT1
tDF tDF
tWO
DS21610
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Output Frame Sync Alignment When CLKOUT2 = 2 x CLKOUT1
Output Frame Sync Alignment When CLKOUT2 = 3 x CLKOUT1
SYNCOUT
CLKOUT2
(8.192MHz)
CLKOUT1
(4.096MHz)
SYNCOUT
CLKOUT2
(
6.176MHz
)
CLKOUT1
(3.088MHz)
CLKOUT2
(7.680MHz or
6.144MHz)
CLKOUT1
(2.56MHz or
2.048MHz)
SYNCOUT
DS21610
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Output Frame Sync Alignment When CLKOUT2 = 4 x CLKOUT1
Output Frame Sync Alignment When CLKOUT2 = 5 x CLKOUT1
CLKOUT2
(6.176MHz or
8.192MHz)
CLKOUT1
(1.544MHz or
2.048MHz)
SYNCOUT
(
short
)
SYNCOUT
(long)
CLKOUT2
(7.720MHz)
CLKOUT1
(1.544MHz)
SYNCOUT
DS21610
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5. PACKAGE SPECIFICATIONS
Figure 5-1. PACKAGE OUTLINE 16-PIN SO 0.300″ BODY
DS21610
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Figure 5-2. PACKAGE OUTLINE PLCC 28-PIN PACKAGE
LTR MIN MAX
A 0.165 0.180
A1 0.090 0.120
A2 0.02 -
B 0.026 0.033
B1 0.013 0.021
C 0.009 0.012
D 0.485 0.495
D1 0.450 0.456
D2 0.390 0.430
E 0.485 0.495
E1 0.450 0.456
E2 0.390 0.430
L1 0.060 -
N 28 -
E1 0.050 BSC
Ch1 0.042 0.048
DS21610
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6. REVISION HISTORY
1) Preliminary release, 090100.
2) Remove references to 3V operation, 112700.
3) Add FSP pin to block diagram, 120600.
4) Add mechanical drawings for PLCC package, 021501.
5) Added jitter specifications and pinout for all packages, 060601.
6) Added timing diagrams, 082001.
7) Updated jitter specifications, 032002.
