CY28325-3 Datasheet, PDF (1/19 Pages) Cypress Semiconductor – FTG for VIA Pentium 4 Chipsets

CY28325-3
FTG for VIA™ Pentium 4™ Chipsets
Features
• Spread Spectrum Frequency Timing Generator for VIA
PT/M 266-800 Pentium^ 4 Chipsets
• Programmable clock output frequency with less than 1 MHz
increment
• Integrated fail-safe Watchdog Timer for system recovery
• Selectable hardware or software-programmed clock
frequency when Watchdog Timer time-out
• Capable to generate system RESET after a Watchdog
Timer time-out occurs or a change in output frequency via
SMBus interface
• Support SMBus Byte Read/Write and Block Read/Write
operations to simplify system BIOS development
• Vendor ID and Revision ID support
• Programmable-drive strength support
• Programmable-output skew support
• Three copies AGP Clocks
• Power management control inputs
• Available in 48-pin SSOP
CPU
AGP
PCI
REF
APIC
48M 24_48M
x3
x3
x9
x1
x2
x1
x1
Block Diagram
X1
X2
*(FS0:4)
VTT_PWRGD#
*CPU_STOP#
*MULTSEL1
XTAL
OSC
PLL Ref Freq
PLL 1
Divider
Network
Stop
Clock
Control
PD#
*PCI_STOP#
PLL2
Stop
Clock
Control
Pin Configuration ^[1]
VDD_REF
REF
SSOP-48
VDD_CPU_CS (2.5V)
CPUT_CS, CPUC_CS
VDD_CPU (3.3V)
*FS4/REF 1
VDD_REF 2
CPUT_0,1, CPUC_0,1
GND_REF 3
X1 4
X2 5
VDD_48MHz 6
VDD_APIC
*FS3/48MHz 7
APIC0:1
*FS2/24_48MHz 8
GND_48MHz 9
VDD_AGP
*FS0/PCI_F 10
AGP0:2
*FS1/PCI1 11
*MULT_SEL1/PCI2 12
VDD_PCI
PCI_F
GND_PCI 13
PCI3 14
PCI4 15
PCI1:8
VDD_PCI 16
PCI5 17
PCI6 18
PCI7 19
GND_PCI 20
PCI8 21
*PD# 22
VDD_48MHz
48MHz
AGP0 23
VDD_AGP 24
48 VDD_APIC
47 GND_APIC
46 APIC0
45 APIC1
44 GND_CPU
43 VDD_CPU_CS(2.5V)
42 CPUT_CS_F
41 CPUC_CS_F
40 CPUT_0
39 CPUC_0
38 VDD_CPU(3.3V)
37 IREF
36 GND_CPU
35 CPUT_1
34 CPUC_1
33 VTT_PWRGD#
32 CPU_STOP#*
31 PCI_STOP#*
30 RST#
29 SDATA
28 SCLK
27 AGP2
26 AGP1
25 GND_AGP
SDATA
SCLK
SMBus
Logic
24_48MHz
2
RST#
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 #: 38-07590 Rev. *.*
Revised May 12, 2004