Clock Generator for Intel® Calistoga Chipset
CY28446
Cypress Semiconductor Corporation 198 Champion Court San Jose,CA 95134-1709 408-943-2600
Document #: 001-00168 Rev *D Revised April 03, 2006
Features
Compliant to Intel® CK410M
Selectable CPU frequencies
Low power differential CPU clock pairs
100-MHz low power differential SRC clocks
96-MHz low power differential DOT clock
48-MHz USB clock
SRC clocks stoppable through OE#
33-MHz PCI clocks
Buffered 14.318-MHz reference clock
Low-voltage frequency select input
•I
2C support with readback capabilities
Ideal Lexmark Spread Spectrum profile for maximum
electromagnetic interferen ce (EMI) reduction
3.3V p ower supply
64-pin QFN package
Table 1. Output Configur ation table
CPU SRC PCI REF DOT96 48M
x2 / x3 x9/10 x5 x1 x 1 x 1
Pin Configuration
OE1#
FS_B/TEST_MODE
DOTC_96
DOTT_96
VDD_48
VSS_PCI
USB_48/FS_A
FS_C/TEST_SEL
VTTPWRGD#/PD
VSS_PCI
VDD_PCI
PCIF0/ITP_EN
PCI0
PCI1
PCI2
PCI3
64 63 62 61 60 59 58 57 56 55 54 53 52 51 50 49
VSS_48 1 48 VDD_PCI
SRCT0 2 47 REF
SRCC0 3 46 VSS_REF
OE0# 4 45 XIN
SRCT1 5 44 XOUT
SRCC1 6 43 VDD_REF
OEA# 7 42 SDATA
SRCT2 8 41 SCLK
SRCC2 9 40 CPU_STOP#
VDD_SRC 10 39 CPUT0
VSS_SRC 11 38 CPUC0
OE3# 12 37 VSS_CPU
SRCT3 13 36 VDD_CPU
SRCC3 14 35 CPUT1
OE6# 15 34 CPUC1
PCI_STOP# 16 33 VSS_SRC
17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32
VDD_SRC
SRCT5
SRCC5
SRCC6
SRCT6
SRCT8
SRCC8
OEB#
SRCC9
SRCT9
SRCT10
SRCC10
VDD_SRC
VSS_SRC
CPUC2_ITP/SRCC7
CPUT2_ITP/SRCT7
CY28446
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Document #: 001-00168 Rev *D Page 2 of 21
Table 2. Frequenc y Table
FS_C FS_B FS_A CPU SRC/SATA PCIF/PCI REF LCD DOT96 USB
MID 0 1 100 100 33 14.318 100 96 48
0 0 1 133 100 33 14.318 100 96 48
0 1 1 166 100 33 14.318 100 96 48
0 1 0 200 100 33 14.318 100 96 48
00 0
MID 0 0
MID 1 0
MID 1 1 Reserved 100 33 14.318 100 96 48
1 0 x Hi-Z Hi-Z Hi-Z Hi-Z Hi-Z Hi-Z Hi-Z
1 1 0 REF/2 REF/8 REF/24 REF REF/8 REF REF
1 1 1 REF/2 REF/8 REF/24 REF REF/8 REF REF
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Pin Description
Pin No. Name Type Description
1 VSS_48 GND Ground for outputs.
2, 3, 5, 6, 8,
9, 13, 14, 18,
19, 20, 21,
22, 23, 25,
26, 27, 28
SRC(0:3, 5:6, 8:10)
[T/C] O, DIF 100-MHz Differential serial reference clocks
4, 7, 12, 15,
24, 64 OE[0, 1, 3, 6, A, B]# I, PU 3.3V LVTTL input for enabling assigned SRC clock (active LOW)
10, 17, 29, VDD_SRC PWR 3.3V power supply for outputs.
11, 30, 33 VSS_SRC GND Ground for outputs.
16 PCI_STP# I, PU 3.3V LVTTL input for PCI_STP#
Stops SRC and PCI clocks not set to free running in the SMBUS registers.
31, 32 CPU2_ITPT/SRCT7,
CPU2_ITPC/ SRCC7 O, DIF Select able differential CPU clock/100-MHz Differen tial serial reference clock.
Selectable via Pin 53 PCIF0/ITP_EN
34, 35, 38, 39 CPUT/C[0:1] O, DIF Differential CPU clock outputs.
36 VDD_CPU PWR 3.3V power supply for outputs.
37 VSS_CPU GND Ground for outputs.
40 CPU_STP# I, PU 3.3V LVTTL input for CPU_STP# active LOW.
41 SCLK I SMBus-compatible SCLOCK.
42 SDATA I/O,
OD SMBus-compatible SDATA.
43 VDD_REF PWR 3.3V power supply for outputs.
44 XOUT O, SE 14.318-MHz crystal output.
45 XIN I 14.318-MHz crystal input.
46 VSS_REF GND Ground for outputs.
47 REF O,SE Fixed 14.318-MH z clo ck output.
48, 54 VDD_PCI PWR 3.3V power supply for outputs.
49, 50, 51, 52 PCI[0:3] O, SE 33-MHz clock output
53 PCIF0/ITP_EN I/O, PD 33-MHz clock output (not stoppable by PCI_STOP#) / 3.3V LVTTL input for
selecting pins 31/3 2 (CPU2_ IT P[T/C]/SRC7[T/C]) (sampled on the
VTT_PWRGD# assertion).
0 (default): SRC7 [T/C]
1: CPU2_ITP[T/C]
55, 59 VSS_PCI GND Ground for outputs.
56 VTT_PWRGD#/PD I, PD 3.3V L VTTL input. This pin is a level sensitive strobe used to latch the FS_A, FS_B,
FS_C, and all I/O configuration pins,. After VTT_PWRGD# (active LOW) assertion,
this pin becomes a real-time input for asserting power-down (active HIGH).
57 FS_C/TEST_SEL I, PD 3.3V-tolerant input for CPU frequency selection/Selects test mode if pulled to
VIMFS_C when VTT_PWRGD# is asserted LOW.
Refer to DC Electrical Specifications table for VILFS_C,VIMFS_C,VIHFS_C specifica-
tions.
58 USB_48/FS_A I/O, PU Fixed 48-MHz clock output / 3.3V -tolerant input for CPU frequency selection.
Refer to DC Electrical Specifications table for Vil_FS and Vih_FS specifications.
60 VDD_48 PWR 3.3V power supply for outputs.
61,62 DOT_96[T /C] O, DIF Fixed 96-M Hz c loc k outp ut .
63 FS_B/TEST_MODE I, PU 3.3V-tolerant input for CPU frequency selection Selects Ref/N or Tri-state
when in test mode
0 = T ri-state, 1 = Ref/N
Refer to DC Electrical Specifications table for Vil_FS and Vih_FS specifications.
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Frequency Select Pins (FS_A, FS_B, and FS_C)
Host clock frequency selection is achieved by applying the
appropriate logic level s to FS_A, FS_B, FS_C inputs prior to
VTT_PWRGD# assertion (as seen by the clock synthesizer).
Upon VTT_PWRGD# being sampled LOW by the clock chip
(indicating processor VTT voltage is stable), the clock chip
samples the FS_A, FS_B, and FS_C input values. For all logic
levels of FS_A, FS_B, and F S_C, VTT_PWRGD# employs a
one-shot functionality in that once a valid LOW on
VTT_PWRGD# has been sampled, all further VTT_PWRGD#,
FS_A, FS_B, and FSC transitions will be ignored, except in
test mode.
Serial Data Interface
To enhance the flexibility and function of the clock synthesizer ,
a two-signal serial interface is provided. Through the Serial
Data Interface, various device functions, such as individual
clock output buffers, can be individually enabled or disabled.
The registers associated with the Serial Data Interface
initialize to their de fault setting upon power-up, and therefore
use of this interface is optional. Clock device register changes
are normally made upon system initialization, if any are
required. The interface cannot be used during system
operation for power management functions.
Data Protocol
The clock driver serial protocol accepts byte write, byte read,
block write, and block read operations from the controller . For
block write/read operation, the bytes must be accessed in
sequential order from l owest to highest byte (most signifi cant
bit first) with the ability to stop after any complete byte has
been transferred. For byte write and byte read operations, the
system controller can access individually indexed bytes. The
offset of the indexed byte is encoded in the command code,
as described in Table 3.
The block write and block read protocol is outli ned in Table 4
while Table 5 outlines the corresponding byte write and byte
read protocol. The slave receiver address is 11010010 (D2h).
Table 3. Comman d Code De fi nition
Bit Description
7 0 = Block read or block write operation, 1 = Byte read or byte write operation
(6:0) Byte offset for byte read or byte write operation. For block read or block write operations, these bits should be
'0000000'
Table 4. Block Read and Block Write Protocol
Block Write Protocol Block Read Protocol
Bit Description Bit Description
1 Start 1 Start
8:2 Slave address – 7 bits 8:2 Slave address – 7 bits
9 Write 9 Write
10 Acknowledge from slave 10 Acknowledge from slave
18:11 Command Code – 8 bits 18:11 Command Code – 8 bits
19 Acknowledge from slave 19 Acknowledge from slave
27:20 Byte Count – 8 bits
(Skip this step if I2C_EN bit set) 20 Repeat start
28 Acknowledge from slave 27:21 Slave address – 7 bits
36:29 Data byte 1 – 8 bits 28 Read = 1
37 Acknowledge from slave 29 Acknowledge from slave
45:38 Data byte 2 – 8 bits 37:30 Byte Count from slave – 8 bits
46 Acknowledge from slave 38 Acknowledge
.... Data Byte /Slave Acknowledges 46:39 Data byte 1 from slave – 8 bits
.... Data Byte N – 8 bits 47 Acknowledge
.... Acknowledge from slave 55:48 Data byte 2 from slave – 8 bits
.... Stop 56 Acknowledge
.... Data bytes from slave / Acknowledge
.... Data Byte N from slave – 8 bits
.... NOT Acknowledge
.... Stop
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Table 5. Byte Read and Byte Write Protocol
Byte Write Protocol Byte Read Protocol
Bit Description Bit Description
1Start 1Start
8:2 Slave address – 7 bits 8:2 Slave address – 7 bits
9Write 9Write
10 Acknowledge from slave 10 Acknowledge from slave
18:11 Command Code – 8 bits 18:11 Command Code – 8 bits
19 Acknowledge from slave 19 Acknowledge from slave
27:20 Data byte – 8 bits 20 Repeated start
28 Acknowledge from slave 27:21 Slave address – 7 bits
29 Stop 28 Read
29 Acknowledge from slave
37:30 Data from slave – 8 bits
38 NOT Acknowledge
39 Stop
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Control Registers
Byte 0: Control Register 0
Bit @Pup Name Description
7 1 CPU2_ITP[T/C]/SRC7[T/C] CPU2_ITP[T/C]/SRC[T/C]7 Output Enable
0 = Disable (Tri-state), 1 = Enable
6 1 SRC[T/C]6 SRC[T/C]6 Output Enable
0 = Disable (Tri-state), 1 = Enable
5 1 SRC[T/C]5 SRC[T/C]5 Output Enable
0 = Disable (Tri-state), 1 = Enable
4 1 Reserved Reserved
3 1 SRC[T/C]3 SRC[T/C]3 Output Enable
0 = Disable (Tri-state), 1 = Enable
2 1 SRC[T/C]2 SRC[T/C]2 Output Enable
0 = Disable (Tri-state), 1 = Enable
1 1 SRC[T/C]1 SRC[T/C]1 Output Enable
0 = Disable (Tri-state), 1 = Enable
0 1 SRC[T/C]0 SRC[T/C]0 Output Enable
0 = Disable (Tri-state), 1 = Enable
Byte 1: Control Register 1
Bit @Pup Name Description
7 1 PCIF0 PCIF0 Output Enable
0 = Disable, 1 = Enable
6 1 DOT_96[T/C] DOT_96 MHz Output Enable
0 = Disable (Tri-state), 1 = Enable
5 1 USB_48 USB_48 Output Enable
0 = Disable, 1 = Enable
4 1 REF REF Output Enable
0 = Disable, 1 = Enable
3 1 Reserved Reserved
2 1 CPU[T/C]1 CPU[T/C]1 Output Enable
0 = Disable (Tri-state), 1 = Enable
1 1 CPU[T/C]0 CPU[T/C]0 Output Enable
0 = Disable (Tri-state), 1 = Enable
0 0 CPU PLL Spread Enable PLL1 (CPU PLL) Spread Spectrum Enable
0 = Spread off
1 = Spread on (–0.5% spread spectrum on CPU/SRC/PCI clocks)
Byte 2: Control Register 2
Bit @Pup Name Description
7 1 Reserved Reserved set to 1
6 1 Reserved Reserved set to 1
5 1 PCI3 PCI3 Output Enable
0 = Disable, 1 = Enable
4 1 PCI2 PCI2 Output Enable
0 = Disable, 1 = Enable
3 1 PCI1 PCI1Output Enable
0 = Disable, 1 = Enable
2 1 PCI0 PCI0 Output Enable
0 = Disable, 1 = Enable
1 1 Reserved Reserved set to 1
0 1 Reserved Reserved set to 1
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Byte 3: Control Register 3
Bit @Pup Name Description
7 0 SRC7 Allow control of SRC[T/C]7 with assertion of OEB#
0 = Free running, 1 = Stopped with OEB#
6 0 Reserved Reserved set to 0
5 0 SRC5 Allow control of SRC[T/C]5 with assertion of OEB#
0 = Free running, 1 = Stopped with OEB#
4 0 Reserved Reserved set to 0
3 0 Reserved Reserved set to 0
2 0 SRC2 Allow control of SRC[T/C]2 with assertion of OEB#
0 = Free running, 1 = Stopped with OEB#
1 0 Reserved Reserved set to 0
0 0 Reserved Reserved set to 0
Byte 4: Control Register 4
Bit @Pup Name Description
7 1 Reserved Reserved set to 1
6 0 DOT96[T/C ] DOT PWRDWN Drive Mode
0 = Driven in PWRDWN, 1 = Tri-state
5 0 Reserved Reserved set to 0
4 1 Reserved Reserved set to 1
3 0 PCIF0 Allow control of PCIF0 with assertio n of SW and HW PCI_STP#
0 = Free running, 1 = Stopped with PCI_STP#
2 1 CPU[T/C]2 Allow control of CPU[T/C]2 with assertion of CPU_STP#
0 = Free running, 1 = St opped with CPU_STP#
1 1 CPU[T/C]1 Allow control of CPU[T/C]1 with assertion of CPU_STP#
0 = Free running, 1 = St opped with CPU_STP#
0 1 CPU[T/C]0 Allow control of CPU[T/C]0 with assertion of CPU_STP#
0 = Free running, 1 = St opped with CPU_STP#
Byte 5: Control Register 5
Bit @Pup Name Description
7 0 Reserved Reserved set to 0
6 0 CPU[T/C]2 CPU[T/C]2 Stop Drive Mode
0 = Driven when CPU_STP# asserted, 1 = Tri-state when CPU_STP#
asserted
5 0 CPU[T/C]1 CPU[T/C]1 Stop Drive Mode
0 = Driven when CPU_STP# asserted, 1 = Tri-state when CPU_STP#
asserted
4 0 CPU[T/C]0 CPU[T/C]0 Stop Drive Mode
0 = Driven when CPU_STP# asserted, 1 = Tri-state when CPU_STP#
asserted
3 0 SRC[T/C] SRC[T/C] PWRDWN Drive Mode
0 = Driven when PD asserted, 1 = Tri-state when PD asserted
2 0 CPU[T/C]2 CPU[T/C]2 PWRDWN Drive Mode
0 = Driven when PD asserted, 1 = Tri-state when PD asserted
1 0 CPU[T/C]1 CPU[T/C]1 PWRDWN Drive Mode
0 = Driven when PD asserted, 1 = Tri-state when PD asserted
0 0 CPU[T/C]0 CPU[T/C]0 PWRDWN Drive Mode
0 = Driven when PD asserted, 1 = Tri-state when PD asserted
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Byte 6: Control Register 6
Bit @Pup Name Description
7 0 REF/N or Tri-state Select REF/N or Tri-state Select
1 = REF/N, 0 = Tri-state
6 0 Test Mode Test Mode Control
1 = Ref/N or T ristate, 0 = Normal Operation
5 1 Reserved Reserved set to 1
4 0 REF REF Output Drive Strength
0 = Low, 1 = High
3 1 PCI and PCIF clock
outputs except those set
to free running
SW PCI_STP Function
0 = SW PCI_STP assert, 1 = SW PCI_STP deassert
When this bit is set to 0, all STOPPABLE PCI and PCIF outputs will be
stopped in a synchronous manner with no sho rt pul ses.
When this bit is set to 1, all STOPPED PCI and PCIF outputs will resum e
in a synchronous manner with no short pulses.
2 HW FS_C FSC Reflects the value of the FS_C pin sampled on power-up
0 = FSC was low during VTT_PWRGD# assertion
1 HW FS_B FSB Reflects the value of the FS_B pin sampled on power-up
0 = FSB was low during VTT_PWRGD# assertion
0 HW F S_A FSA Reflects the value of the FS_A pin sampled on power-up
0 = FSA was low during VTT_PWRGD# assertion
Byte 7: Vendor ID
Bit @Pup Name Description
7 0 Revision Code Bit 3 Revision Code Bit 3
6 0 Revision Code Bit 2 Revision Code Bit 2
5 1 Revision Code Bit 1 Revision Code Bit 1
4 1 Revision Code Bit 0 Revision Code Bit 0
3 1 Vendor ID Bit 3 Vendor ID Bit 3
2 0 Vendor ID Bit 2 Vendor ID Bit 2
1 0 Vendor ID Bit 1 Vendor ID Bit 1
0 0 Vendor ID Bit 0 Vendor ID Bit 0
Byte 8: Control Register 7
Bit @Pup Name Description
7 0 Reserved Reserved set to 0
6 1 SRC[T/C]10 SRC[T/C]10 Output Enable
0 = Disable (Tri-state), 1 = Enable
5 1 SRC[T/C]9 SRC[T/C]9 Output Enable
0 = Disable (Tri-state), 1 = Enable
4 1 SRC[T/C]8 SRC[T/C]8 Output Enable
0 = Disable (Tri-state), 1 = Enable
3 0 Reserved Reserved set to 0
2 0 SRC10 Allow control of SRC[T/C]10 with assertion of OEA#
0 = Free running, 1 = Stopped with OEA#
1 0 SRC9 Allow control of SRC[T/C]9 with assertion of OEB#
0 = Free running, 1 = Stopped with OEB#
0 0 SRC8 Allow control of SRC[T/C]8 with assertion of OEA#
0 = Free running, 1 = Stopped with OEA#
CY28446
Document #: 001-00168 Rev *D Page 9 of 21
.
The CY28446 requires a Paral lel Resonance Crystal. Substi-
tuting a series resonance crystal will cause the CY28446 to
operate at the wrong frequency and violate the ppm specifi-
cation. For most applications there is a 300-ppm frequency
shift between series and parallel crystals due to incorrect
loading
Crystal Loading
Crystal loading plays a critical role in achieving low ppm perfor-
mance. To realize low ppm performance, the total capacit ance
the crystal will see must be considered to calculate the appro-
priate capacitive loading (CL).
Figure 1 shows a typical crystal configuration using the two
trim capacitors. An important clarification for the following
discussion is that the trim capacitors are in series with the
crystal not parallel. It’s a common misconception that load
capacitors are in parallel with the crystal and should be
approximately equal to the load capacitance of the crystal.
This is not true.
Calculating Load Capacitors
In addition to the standard external trim capacitors, trace
capacitance and pin capacitance must also be considered to
correctly calculate crystal loading. As mentioned previously,
the capacitance on each side of the crystal is in series with the
crystal. This means the total capacitance on each side of the
crystal must be twice the specified crystal load capacitance
(CL). While the capacitance on each side of the crystal is in
series with the crystal, trim capacitors (Ce1,Ce2) should be
calculated to provide equal capaciti ve loading on both sides.
As mentioned previously, the capacitance on each side of the
crystal is in series with the crystal. This mean the tot al cap ac-
itance on each side of the crystal must be twice the specified
load capacitance (CL). While the capacitance on each side of
the crystal is in series with the crystal, trim capacitors
(Ce1,Ce2) should be calcula ted to provide equal capacitance
loading on both sides.
Byte 9: Control Register 8
Bit @Pup Name Description
7 0 PCI3 33-MHz Output drive strength
0 = Low, 1 = High
6 0 PCI2 33-MHz Output drive strength
0 = Low, 1 = High
5 0 PCI1 33-MHz Output drive strength
0 = Low, 1 = High
4 0 PCI0 33-MHz Output drive strength
0 = Low, 1 = High
3 0 PCIF0 33-MHz Output drive strength
0 = Low, 1 = High
2 1 Reserved Reserved set to 1
1 1 Reserved Reserved set to 1
0 1 Reserved Reserved set to 1
Crystal Recommendations
Frequency
(Fund) Cut Loading Load Cap Drive
(max.) Shunt Cap
(max.) Motional
(max.) Tolerance
(max.) Stability
(max.) Aging
(max.)
14.31818 MHz AT Parallel 20 pF 0.1 mW 5 pF 0.016 pF 35 ppm 30 ppm 5 ppm
Figure 1. Crystal Cap acitive Clarification
XTAL
Ce2
Ce1
Cs1 Cs2
X1 X2
Ci1 Ci2
Clock Chip
Trace
2.8 pF
Trim
33 pF
Pin
3 to 6p
Figure 2. Crystal Loading Example
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Document #: 001-00168 Rev *D Page 10 of 21
Use the following formulas to calculate the trim capacitor
values for Ce1 and Ce2.
CL ...................................................Crystal load capacitance
CLe .........................................Actual loading seen by crystal
using standard value trim capacitors
Ce .....................................................External trim capacitors
Cs..............................................Stray capacitance (terraced)
Ci ...........................................................Internal capacitance
(lead frame, bond wires etc.)
OE# Description
The OE# signals are active LOW inputs used for clean
enabling and disabling selected SRC outputs. The outputs
controlled by OE[A,B]# are determined by the settings in
register byte 3 and byte 8. OE[0,1,3,6]# controls SRC[0,1,3,6],
respectively. The OE# signal i s a debounced signa l in that its
state must remain unchanged during two consecutive rising
edges of SRCC to be recognized as a valid assertion or
deassertion. (The assertion and deassertion of this signal is
absolutely asynchronous.)
OE# Assertion (OE# -> LOW)
All differential outputs that were stopped are to resume normal
operation in a glitch-fre e manner. The maximum latency from
the assertion to active outputs is between 2 and 6 SRC clock
periods (2 clocks are shown) with all SRC outputs resuming
simultaneously . All stopped SRC outputs must be driven HIGH
within 10 ns of OE# deassertion to a voltage greater than
200 mV.
OE# Deassertion (OE# -> HIGH)
The impact of deasserting the OE# pins is that all SRC outputs
that are set in the control registers to stoppable via deassertion
of OE# are to be stopped a fter their next transition. The final
state of all stopped SRC clocks is Low/Low.
PD (Power-down) Clarification
The VTT_PWRGD# /PD pin is a dual-function pin. During
initial power-up, the pin functions as VTT_PWRGD#. Once
VTT_PWRGD# has been sampled LOW by the clock chip, the
pin assumes PD functionality. The PD pin is an asynchronous
active HIGH input used to shut off all clocks cleanly prior to
shutting off power to the device. This signal is synchronized
internal to the device prior to powering down the clock synthe-
sizer. PD is also an asynchronous input for powering up the
system. When PD is asserted HIGH, all clocks need to be
driven to a low value and held prior to turning off the VCOs and
the crystal oscillator.
PD (Power-down) Asser tio n
When PD is sampled HIGH by two consecutive rising edges
of CPUC, all single-ended outputs will be held LOW on their
next HIGH-to-LOW transition and dif ferential clocks must held
HIGH or tri-stated (depending on the state of the control
register drive mode bit) on the n ext diff clock# HIGH-to-LOW
transition within 4 clock periods. When the SMBus PD drive
mode bit corresponding to the differential (CPU, SRC, and
DOT) clock output of interest is progra mmed to ‘0’, the clock
output are held with “Diff clock” pin driven HIGH and “Diff
clock#” driven LOW. If th e control register PD drive mode bit
corresponding to the output of interest is progra mmed to “1”,
then both the “Diff clock” and the “Diff clock#” are LOW. Note
Figure 4 shows CPUT = 133 MHz and PD drive mode = ‘1’ for
all differential outputs. This diagram and description is appli-
cable to valid CPU frequenci es 100, 1 33, 166, and 200 MHz.
In the event that PD mode is desired as the initial power-on
state, PD must be asserted HIGH in less than 10 µs after
asserting Vtt_PwrGd#. It should be noted that 96_100_SSC
will follow the DOT wavefo rm is selected for 96 MHz and the
SRC waveform when in 100-MHz mode.
Load Capacitan ce (each side)
Total Capacitance (as seen by the crystal)
Ce = 2 * CL – (Cs + Ci)
Ce1 + Cs1 + Ci1
1+Ce2 + Cs2 + Ci2
1
()
1
=
CLe
Figure 3. OE# Deassertion/Assertion Waveform
SRCT(stoppable)
SRCT(stoppable)
SRCC(free running)
SRCT(free running)
OE#
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PD Deassertion
The power-up latency is less than 1.8 ms. This is the time from
the deassertion of the PD pin or the ramping of the power
supply until the time that stable clocks are output from the
clock chip. All differential outputs stopped in a three-state
condition resulting from power-down will be driven HIGH in
less than 300 µs of PD deassertion to a voltage greater than
200 mV. After the clock chip’s internal PLL is powered up and
locked, all outputs will be enabled within a few clock cycles of
each other . Figure 5 is an example showing the relationship of
clocks coming up. It should be noted that 96_100_SSC will
follow the DOT waveform is selected for 96 MHz and the SRC
waveform when in 100-MHz mode.
Figure 4. Power-down Assertion Timing Waveform
PD
USB, 48MHz
DOT96T
DOT96C
SR CT 100MHz
SRCC 100MHz
CPUT, 133MHz
PCI, 33 MHz
REF
CP UC , 133MHz
Figure 5. Power-down Deassertion Timing Waveform
DOT96C
PD
CPUC, 133MHz
CPUT, 133MHz
SRCC 100MHz
USB, 48MH z
DOT96T
SRCT 100MH z
Tstable
<1.8 ms
PCI, 33MHz
REF Tdrive_PWRDN#
<300 µσ, >200 mV
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CPU_STP# Assertion
The CPU_STP# signal is an active LOW input used for
synchronous stopping and starting the CPU output clocks
while the rest of the clock generator continues to function.
When the CPU_STP# pin is asserted, all CPU outputs that are
set with the SMBus configurat ion to be stoppable via assertion
of CPU_STP# will be stopped within two to six CPU clock
periods after being sampled by two rising edges of the internal
CPUC clock. The final state of all stopped CPU clocks is
High/Low when driven, Low/Low when tri-stated
CPU_STP# Deassertion
The deassertion of the CPU_ STP# signal will cause all CPU
outputs that were stopped to resume normal operation in a
synchronous manner, synchronous manner meaning that no
short or stretched clock pulses will be produce when the clock
resumes. The maximum latency from the deassertion to active
outputs is no more than two CPU clock cycles.
CPU_STP#
CPUT
CPUC
CP U T Inte rnal
Tdrive_CPU_STP#,10 ns > 200 mV
CP U C Inte rna l
Figure 6. CPU_STP# Deassertion Waveform
DOT96C
DOT96T
CPUC(Stoppable)
CPUT(Stoppable)
CP UC (Free Running
CPUT(Free Running
PD
1.8 m s
CPU_STOP#
Figure 7. CPU_STP#= Driven, CPU_PD = Driven, DOT_PD = Driven
CPU_STP#
CPUT
CPUC
Figure 8. CPU_STP# Assertion Waveform
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PCI_STP# Assertion
The PCI_STP# signal is an active LOW input used for
synchronous stopping and starting the PCI outputs while the
rest of the clock generator continues to function. The set-up
time for capturing PCI_STP# goi ng LOW is 10 ns (tSU). (See
Figure 10.) The PCIF clocks will not be affected by this pin if
their corresponding control bit in the SMBus re gister is set to
allow them to be free running.
PCI_STP# Deassertion
The deassertion of the PCI_STP# signal will cause all PCI and
stoppable PCIF clocks to resume running in a synchronous
manner within two PCI clock periods after PCI_STP# transi-
tions to a high level.
DOT96C
DOT96T
CPUC(Stoppable)
CPUT(Stoppable)
CPUC(Free Running)
CPUT(Free Running)
PD
1.8mS
CPU_STOP#
Figure 9. CPU_STP# = Tri-state, CPU_PD = Tri-state, DOT_PD = Tri-state
Tsu
PCI_STP#
PCI_F
PCI
SRC 100MHz
Figure 10. PCI_STP# Assertion Waveform
PCI_STP#
PCI_F
PCI
SRC 100MHz
Tsu Tdrive_SRC
Figure 11. PCI_STP# Deassertion Waveform
CY28446
Document #: 001-00168 Rev *D Page 14 of 21
FS_A, FS_B,FS_C
VTT_PWRGD#
PWRGD_VRM
VDD C lock Gen
Clock State
Clock Outputs
Clock VCO
0.2-0.3mS
Delay
State 0 State 2 State 3
Wait for
VTT_PWRGD# S ample Sels
Off
Off
On
On
State 1
Device is not aff ect ed,
VT T_P WR G D # is ignored
Figure 12. VTT_PWRGD# Timing Diagram
VTT_PWRGD # = Low
Delay
>0.25mS
S1
Power Off
S0
VDD_A = 2.0V
Sample
Inputs straps
S2
Normal
Operation
W a it fo r <1 .8 m s
Enable Outputs
S3
VTT_PWRGD # = toggle
VDD_A = off
Figure 13. Clock Generator Power-up/Run State Diagram
CY28446
Document #: 001-00168 Rev *D Page 15 of 21
Absolute Maximum Conditions
Parameter Description Condition Min. Max. Unit
VDD Core Supply Voltage –0.5 4.6 V
VDD_A Analog Supply Voltage –0.5 4.6 V
VIN Input Voltage Relative to VSS –0.5 VDD + 0.5 VDC
TSTemperature, Storage Non-functional –65 150 °C
TATemperature, Operating Ambient Functional 0 85 °C
TJTemperature, Junction Functional 150 °C
ØJC Dissipation, Junction to Case Mil-STD-883E Method 1012.1 20 °C/W
ØJA Dissipation, Junction to Ambient JEDEC (JESD 51) 60 °C/W
ESDHBM ESD Protection (Human Body Model) MIL-STD-883, Method 3015 2000 V
UL-94 Flammabi lity Rating At 1/8 in. V–0
MSL Moisture Sensi ti vity Leve l 1
Multiple Supplies: The Voltage on any input or I/O pin cannot exceed the power pin during power -up. Power supply sequencing is NOT required.
DC Electrical Specifications
Parameter Description Condition Min. Max. Unit
All VDDs 3.3V Operating V oltage 3.3 ± 5% 3.135 3.465 V
VILI2C Input Low Voltage SDATA, SCLK 1.0 V
VIHI2C Input High Voltage SDATA, SCLK 2.2 V
VIL_FS FS_[A,B] Input Low Voltage VSS – 0.3 0.35 V
VIH_FS FS_[A,B] Input High Voltage 0.7 V DD + 0.5 V
VILFS_C FS_C Input Low Voltage VSS – 0.3 0.35 V
VIMFS_C FS_C Input Middle Vo ltage Typical 0.7 1.7 V
VIHFS_C FS_C Input High Voltage Typical 2.0 VDD + 0.5 V
VIL 3.3V Input Low Voltage VSS – 0.3 0.8 V
VIH 3.3V Input High Voltage 2.0 VDD + 0.3 V
IIL Input Low Leakage Current Except internal pull-up resistors, 0 < VIN
< VDD –5 5 µA
IIH Input High Leakage Current Except internal pull-down resistors, 0 <
VIN < VDD –5µA
VOL 3.3V Output Low Voltage IOL = 1 mA 0.4 V
VOH 3.3V Output High Voltage IOH = –1 mA 2.4 V
IOZ High-impedance Output Current –10 10 µA
CIN Input Pin Ca pacitance 3 5 pF
COUT Output Pin Capacitance 3 6 pF
LIN Pin Inductance 7 nH
VXIH Xin High Voltage 0.7VDD VDD V
VXIL Xin Low Voltage 0 0.3VDD V
IDD3.3V Dynamic Supply Current At max. load and freq. per Figure 15 250 mA
IPD3.3V Power-down Supply Curre nt PD asserted, Outputs Driven 70 mA
IPD3.3V Power-down Supply Current PD asserted, Outputs Tri-state 5 mA
CY28446
Document #: 001-00168 Rev *D Page 16 of 21
AC Electrical Specifications
Parameter Description Condition Min. Max. Unit
Crystal
TDC XIN Duty Cycle The device will operate reliably with input
duty cycles up to 30/70 but the REF clock
duty cycle will not be within specification
47.5 52.5 %
TPERIOD XIN Period When XIN is driven from an external
clock source 69.841 71.0 ns
TR / TFXIN Rise and Fall Times Measured between 0.3VDD and 0.7VDD –10.0ns
TCCJ XIN Cycle to Cycle Jitter As an average over 1-µs duration 500 ps
LACC Long-term Accuracy Measured at crossing point VOX –300ppm
CPU at 0.8V
TDC CPUT and CPUC Duty Cycle Measured at crossing point VOX 45 55 %
TPERIOD 100-MHz CPUT and CPUC Period Measured at crossing point VOX 9.997001 10.00300 ns
TPERIOD 133-MHz CPUT and CPUC Period Measured at crossing point VOX 7.497751 7.502251 ns
TPERIOD 166-MHz CPUT and CPUC Period Measured at crossing point VOX 5.998201 6.001801 ns
TPERIOD 200-MHz CPUT and CPUC Period Measured at crossing point VOX 4.998500 5.001500 ns
TPERIODSS 100-MHz CPUT and CPUC Period, SSC Measured at crossing point VOX 9.997001 10.05327 ns
TPERIODSS 133-MHz CPUT and CPUC Period, SSC Measured at crossing point VOX 7.497751 7.539950 ns
TPERIODSS 166-MHz CPUT and CPUC Period, SSC Measured at crossing point VOX 5.998201 6.031960 ns
TPERIODSS 200-MHz CPUT and CPUC Period, SSC Measured at crossing point VOX 4.998500 5.026634 ns
TPERIODAbs 100-MHz CPUT and CPUC Absolute
period Measured at crossing point VOX 9.912001 10.08800 ns
TPERIODAbs 133-MHz CPUT and CPUC Absolute
period Measured at crossing point VOX 7.412751 7.587251 ns
TPERIODAbs 166-MHz CPUT and CPUC Absolute
period Measured at crossing point VOX 5.913201 6.086801 ns
TPERIODAbs 200-MHz CPUT and CPUC Absolute
period Measured at crossing point VOX 4.913500 5.086500 ns
TPERIODSSAbs 100-MHz CPUT and CPUC Absolute
period, SSC Measured at crossing point VOX 9.912001 10.13827 ns
TPERIODSSAbs 133-MHz CPUT and CPUC Absolute
period, SSC Measured at crossing point VOX 7.412751 7.624950 ns
TPERIODSSAbs 166-MHz CPUT and CPUC Absolute
period, SSC Measured at crossing point VOX 5.913201 6.116960 ns
TPERIODSSAbs 200-MHz CPUT and CPUC Absolute
period, SSC Measured at crossing point VOX 4.913500 5.111634 ns
TCCJ CPUT/C Cycle to Cycle Jitter Measured at crossing point VOX –85
[1] ps
TCCJ2 CPU2_ITP Cycle to Cycle Jitter Measured at crossing point VOX –125ps
LACC Long-term Accuracy Measured at crossing point VOX –300ppm
TSKEW2 CPU2_ITP to CPU0 Clock Skew Measured at crossing point VOX –150ps
TR / TFCPUT and CPUC Rise and Fall Time Measur ed from VOL = 0.175 to
VOH = 0.525V 175[1] 700 ps
TRFM Rise/Fall Matching Determined as a fraction of
2*(TR – TF)/(TR + TF)–20%
TRRise Time Variation 125 ps
TFFall Time Variation 125 ps
VHIGH Voltage High Math averages Figure 15 660 850 mV
Note:
1. Measured at typical condition. VDD = 3.3V, Temp=25°C.
CY28446
Document #: 001-00168 Rev *D Page 17 of 21
VLOW Voltage Low Math averages Figure 15 –150 mV
VOX Crossing Point Voltage at 0.7V Swing 250[1] 550 mV
VOVS Maximum Overshoot Voltage VHIGH +
0.3 V
VUDS Minimum Undershoot Voltage –0.3 V
VRB Ring Back Voltage See Figure 15. Measure SE 0.2 V
SRC at 0.8V
TDC SRCT and SRCC Duty Cycle Measu r ed at crossing poi nt VOX 45 55 %
TPERIOD 100-MHz SRCT and SRCC Period Measured at crossing point VOX 9.997001 10.00300 ns
TPERIODSS 100-MHz SRCT and SRCC Period, SSC Measured at crossing point VOX 9.997001 10.05327 ns
TPERIODAbs 100-MHz SRCT and SRCC Absolute
Period Measured at crossing point VOX 9.872001 10.12800 ns
TPERIODSSAbs 100-MHz SRCT and SRCC Absolute
Period, SSC Measured at crossing point VOX 9.872001 10.17827 ns
TSKEW Any SRCT/C to SRCT/C Clock Skew Measured at crossing point VOX –100ps
TCCJ SRCT/C Cycle to Cycle Jitter Measured at crossing point VOX –125ps
LACC SRCT/C Long Term Accuracy Measured at crossing point VOX –300ppm
TR / TFSRCT and SRCC Rise and Fall Time Measured fro m VOL = 0.175 to
VOH = 0.525V 175[1] 700[1] ps
TRFM Rise/Fall Matching Determined as a fraction of
2*(TR – TF)/(TR + TF)–20%
TRRise TimeVariation 125 ps
TFFall Time Variation 125 ps
VHIGH Voltage High Math averages Figure 15 660 850 mV
VLOW Voltage Low Math averages Figure 15 –150 mV
VOX Crossing Point Voltage at 0.7V Swing 250 550 mV
VOVS Maximum Overshoot Voltage VHIGH +
0.3 V
VUDS Minimum Undershoot Voltage –0.3 V
VRB Ring Back Voltage See Figure 15. Measure SE 0.2 V
DOT96 at 0.7V
TDC DOT96T and DOT96C Duty Cycle Measured at crossing point VOX 45 55 %
TPERIOD DOT96T and DOT96C Period Measured at crossing point VOX 10.41354 10.41979 ns
TPERIODAbs DOT96T and DOT96C Absolute Period Measured at crossing point VOX 10.16354 10.66979 ns
TCCJ DOT96T/C Cycle to Cycle Jitter Measured at crossing point VOX –250ps
LACC DOT96T/C Long Term Accuracy Measured at crossing point VOX –300ppm
TR / TFDOT96T and DOT96C Rise and Fall
Time Measured from VOL = 0.175 to
VOH = 0.525V 175 [1] 700 ps
TRFM Rise/Fall Matching Determined as a fraction of
2*(TR – TF)/(TR + TF)–20%
TRRise Time Variation 125 ps
TFFall Time Variation 125 ps
VHIGH Voltage High Math averages Figure 15 660 850 mV
VLOW Voltage Low Math averages Figure 15 –150 mV
VOX Crossing Point Voltage at 0.7V Swing 250 550 mV
AC Electrical Specifications (continued)
Parameter Description Condition Min. Max. Unit
CY28446
Document #: 001-00168 Rev *D Page 18 of 21
VOVS Maximum Overshoot Voltage VHIGH +
0.3 V
VUDS Minimum Undershoot Voltage –0.3 V
VRB Ring Back Voltage See Figure 15. Measure SE 0.2 V
PCI/PCIF at 3.3V
TDC PCI Duty Cycle Measurement at 1.5V 45 55 %
TPERIOD Spread Disabled PCIF/PCI Period Measurement at 1.5V 29.99100 30.00900 ns
TPERIODSS Spread Enabled PCIF/PCI Period, SSC Measurement at 1.5V 29.9910 30.15980 ns
TPERIODAbs Spread Disable d PCIF/PCI Period Measurement at 1.5V 29.49100 30.50900 ns
TPERIODSSAbs Spread Enabled PCIF/PCI Period, SSC Measurement at 1.5V 29.49100 30.65980 ns
THIGH PCIF and PCI high time Measurement at 2.4V 12.0 ns
TLOW PCIF and PCI low time Measurement at 0.4V 12.0 ns
TR / TFPCIF/PCI rising and falling Edge Rate Measured between 0.8V and 2.0V 1.0 4.0 V/ns
TSKEW Any PCI clock to Any PCI clock Skew Measurement at 1.5V 500 ps
TCCJ PCIF and PCI Cycle to Cycle Jitter Measurement at 1.5V 500 ps
LACC PCIF/PCI Long Term Accuracy Measured at crossing point VOX –300ppm
48_M at 3.3V
TDC Duty Cycle Measurement at 1.5V 45 55 %
TPERIOD Period Measurement at 1.5V 20.83125 20.83542 ns
TPERIODAbs Absolute Period Measurement at 1.5V 20.48125 21.18542 ns
THIGH 48_M High time Measurement at 2.4V 8.09 11.3 ns
TLOW 48_M Low time Measurement at 0.4V 7.694 11.3 ns
TR / TFRising and Falling Edge Rate Measured between 0.8V and 2.0V 1.0 4.0 V/ns
TCCJ Cycle to Cycle Jitter Measurement at 1.5V 350 ps
LACC 48M Long Term Accuracy Measured at crossing point VOX –300ppm
REF at 3.3V
TDC REF Duty Cycle Measurement at 1.5V 45 55 %
TPERIOD REF Period Measurement at 1.5V 69.8203 69.8622 ns
TPERIODAbs REF Absolute Period Measurement at 1.5V 68.82033 70.86224 ns
TR / TFREF Rising and Falling Edge Rate Measured betwee n 0.8V and 2.0V 1.0 4.0 V/n s
TSKEW REF Clock to REF Clock Measurement at 1.5V 500 ps
TCCJ REF Cycle to Cycle Jitter Measurement at 1.5V 1000 ps
LACC Long Term Accuracy Measurement at 1.5V 300 ppm
ENABLE/DISABLE and SET-UP
TSTABLE Clock Stabilization from Power-up 1.8 ms
TSS Stopclock Set-up Time 10.0 ns
TSH Stopclock Hold Time 0 ns
AC Electrical Specifications (continued)
Parameter Description Condition Min. Max. Unit
CY28446
Document #: 001-00168 Rev *D Page 19 of 21
Test and Measurement Set-up
For PCI Single-ended Signals and Reference
The following diagram shows the test load configuration of
single-ended PCI, USB output signals.
The following diagram shows the test load configuration for the
differential CPU and SRC outputs.
Figure 14. Single-ended PCI, USB Load Con fi guration
33Ω
5 pF
Figure 15. 0.7V Differential Load Configuration
CPUT
SRCT
DOT96T
TPCB
TPCB
CPUC
SRCC
DTO96C
33Ω
33Ω
L1
L1 L2
L2
100 ohm Differential
2 pF
2 pF
Measurem ent
point
Measurement
point
2.0V
0.8V
3.3V
0V
TR TF
1.5V
3.3V sig nals
TDC
- -
Figure 16. Single-en de d Ou tpu t Sign als (for AC Parameters Measur ement)
Ordering Information
Part Number Package Type Product Flow
Lead-free
CY28446LFXC 64-pin QFN Commercial, 0° to 70°C
CY28446LFXCT 64-pin QFN—Tape and Reel Commercial, 0° to 70°C
CY28446
Document #: 001-00168 Rev *D Page 20 of 21
© Cypress Semi con duct or Cor po rati on , 20 06 . The information con tained herei n is su bject to change wit hou t n oti ce. C ypr ess S em icon duct or Corpo ration assu mes no resp onsib ility for th e us e
of any circuitry other than circuitry embodied in a Cypress product. Nor does it convey or imply any license under patent or other rights. Cypress products are not warranted nor intended to be
used for medical, life support, life saving, critical control or safety applications, unless pursuant to an express written agreement with Cypress. Furthermore, Cyp ress does not a uthorize its
products for use as critical components in life-support systems where a malfunction or failure may reasonably be expected to result in significant injury to the user. The inclusion of Cypress
products in life-support systems application implies that the manufacturer assumes all risk of such use and in doing so indemnifies Cypress against all charges.
Package Diagram
Purchase of I2C components from Cypress or one of its sublicensed Associated Companies conveys a license under the Philips
I2C Patent Rights to use these components in an I2C system, provided that the system conforms to the I2C Standard S pecification
as defined by Philips.
Intel is a registered trademark of Inte l Corporation. All products and company names mentioned in this documen t may be the
trademarks of their respective holders.
2
1
PIN1 ID
0.80 DIA. 3
2
C
PLANE
SEATING
N
A
0.20[0.008] REF.
0.05[0.002] MAX.
0.80[0.031] MAX.
1.00[0.039] MAX.
C0.08[0.003]
1
N
0.20[0.008] R.
9.10[0.358]
8.90[0.350]
8.80[0.346]
8.70[0.342]
8.80[0.346]
8.70[0.342]
9.10[0.358]
8.90[0.350]
-12°
0.28[0.011]
0.18[0.007]
0.30[0.012]
0.50[0.020]
0.50[0.020]
7.55[0.297]
7.45[0.293]
0.45[0.018]
0.60[0.024]
0.24[0.009] (4X)
BY DEVICE TYPE)
(PAD SIZE VARY
E-PAD
TOP VIEW
SIDE VIEW
BOTTOM VIEW
DIMENSIONS IN MM[INCHES] MIN.
MAX.
REFERENCE JEDEC MO-220
WEIGHT: 0.2 GRAMS
51-85215-**
64-Lead QFN 9 x 9 mm (Punch Version) LF64A
CY28446
Document #: 001-00168 Rev *D Page 21 of 21
Document History Page
Document Title: CY28446 Clock Generator for Intel® Calistoga Chipset
Document Number: 001-00168
REV. ECN NO. Issue Date Orig. of
Change Description of Change
** 366781 See ECN RGL New data sheet
*A 385257 See ECN RGL Modify Control register byte 4 and 6
Delete 96_100MHz LCD clock AC timing spec from AC Electrical specifications
table
Modify figure 15 for lower differential buffer
Change pin 33 from IREF to VSS_SRC
Update IDD, IPD number in DC Electrical Specifications table
Updated single-ended PCI, USB loading config. diagram
*B 391184 See ECN RGL Minor Change: corrected the letter suffix for QFN package
*C 402318 See ECN XLZ Modify Control register byte 6, 7, 9
Update DC and AC Electrical Specifications table
*D 436731 See ECN RGL Updated Control register bytes 0,1 and 7
Updated AC Electrical Specifications table
Removed preliminary status