
FTG for Mobile VIA™ PL133T and PLE133T Chipsets
CY28317-2
Cypress Semiconductor Corporation
•
3901 North First Street
•
San Jose
•
CA 95134
•
408-943-2600
Document #: 38-07094 Rev. *B
Revised December 26, 2002
17-2
Features
• Single-chip system frequency synthesizer for mobile
VIA PL133T and PLE133T chipsets
• Programmable clock output frequency with less than
1 MHz increment
• Integrated fail-safe Watchdog Timer for system
recovery
• Automatic switch to HW-selected or SW-programmed
clock frequency when Watchdog Timer time-out occurs
• System RESET generation capability 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 for SDRAM and PCI
output clocks
• Programmable output skew for CPU, PCI and SDRAM
• Maximized EMI Suppression using Cypress’s Spread
Spectrum technology
• Available in 48-pin SSOP and TSSOP packages
Key Specifications
CPU to CPU Output Skew:.......................................... 175 ps
PCI to PCI Output Skew: ............................................. 500 ps
Block Diagram
Pin Configuration
Note:
1.
Signals marked with ‘*’ have internal pull-up resistors.
[1]
VDD_REF
REF0
PCI0_F/FS4*
XTAL
PLL Ref Freq
PLL 1
X2
X1
REF1/FS2*
VDD_PCI
PCI2:6
48MHz/FS0*
24_48MHz/FS1*
PLL2
÷2,3,4
OSC
VTT_PWRGD#
VDD_48MHz
SMBus
SDATA
Logic
SCLK
SDRAM0:6
SDRAMIN
7
VDD_SDRAM
PCI1/FS3*
CPU0:1, CPUT, CPUC
÷2
GND_CPU
*FS2/REF1
REF0
VTT_PWRGD#
VDD_REF
GND_REF
X1
X2
VDD_PCI
*FS4/PCI0_F
*FS3/PCI1
GND_PCI
PCI2
PCI3
PCI4
PCI5
PCI6
SDRAMIN
*CPU_STOP#
*PCI_STOP#
*PD#
*MULT_SEL
GND_48MHz
SDATA
CPU0
CPU1
VDD_CPU_2.5
VDD_CPU_3.3
CPUT
CPUC
GND_CPU
RST#
IREF
SDRAM6
GND_SDRAM
SDRAM0
SDRAM1
VDD_SDRAM
SDRAM2
SDRAM3
GND_SDRAM
SDRAM4
SDRAM5
VDD_SDRAM
VDD_48MHz
48MHz/FS0*
24_48MHz/FS1*
SCLK
48
47
46
45
44
43
42
41
40
39
38
37
36
35
34
33
32
31
30
29
28
27
26
25
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
Logic
Reset
RST#
IREF
MULT_SEL
PCI_STOP#
CPU_STOP#
PD#