CY28342 Datasheet, PDF (1/22 Pages) Cypress Semiconductor – High-performance SiS645/650 Pentium 4 Clock Synthesizer

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CY28342
High-performance SiS645/650 Pentium^ 4 Clock Synthesizer
Features
• Supports Pentium^ 4-type CPUs
• 3.3V power supply
• Eight copies of PCI clocks
• One 4-MHz USB clock
• Two copies of ZCLK clocks
• One 48-MHz/24-MHz programmable SIO clock
• Two differential CPU clock pairs
• SMBus support with read-back capabilities
• Spread Spectrum EMI reduction
• Dial-a-Frequency^® features
• Dial-a-Ratio™ features
• Dial-a-dB^® features
• 48-pin SSOP and TSSOP packages
• Watchdog Function
Block Diagram
Pin Configuration^[1]
XIN
XOUT
PLL1
CPU_STP#
IREF
FS(0:4)
MULT0
Power
on
Latch
VTTPWRGD
/2
PCI_STP#
PLL2
PD#
SDATA
SCLK
WD
Logic
I2C
Logic
REF(0:2)
CPU(0:1)T
CPU(0:1)C
SDCLK
AGP(0:1)
ZCLK(0:1)
PCI(0:5)
PCI_F(0:1)
48M
48M_24M#
SRESET#
VDDR 1
**FS0/REF0 2
**FS1/REF1 3
**FS2/REF2 4
VSSR 5
XIN 6
XOUT 7
VSSZ 8
ZCLK0 9
ZCLK1 10
VDDZ 11
*SRESET#/PCI_STP# 12
VDDP 13
**FS3/PCI_F0 ¹⁴
**FS4/PCI_F1 15
PCI0 16
PCI1 17
VSSP 18
VDDP 19
PCI2 20
PCI3 21
PCI4 22
PCI5 23
VSSP 24
48 VDDSD
47 SDCLK
46 VSSSD
45 CPU_STP#*
44 CPU1T
43 CPU1C
42 VDDC
41 VSSC
40 CPU0T
39 CPU0C
38 IREF
37 VSSA
36 ^VDDA
35 SCLK
34 SDATA
33 PD#/VTTPWRGD*
32 VSSAGP
31 AGP0
30 AGP1
29 VDDAGP
28 VDD48M
27 48M
26 ^{24_48M/MULT0*}
25 ^VSS48M
48 Pin SSOP andf TSSOP
Note:
1. Pins marked with [*] have internal pull-up resistors. Pins marked with [**] have internal pull-down resistors.
Cypress Semiconductor Corporation • 3901 North First Street • San Jose • CA 95134 • 408-943-2600
Document #: 38-07349 Rev. *A
Revised July 29, 2002