W210
Spread Spectrum FTG for VIA K7 Chipset
Features
Table 1. Mode Input Table
Mode
Pin 2
CPU_STOP#
REF0
• Maximized EMI Suppression using Cypress’s Spread
Spectrum technology
• Single-chip system frequency synthesizer for VIA K7
chipset
0
1
Table 2. Pin Selectable Frequency
• One pair of differential CPU outputs for K7 Processor
• One open-drain CPU output for VIA K7 chipset
• Six copies of PCI output
• One 48-MHz output for USB
• One 24-MHz or 48-MHz output for SIO
• Two buffered reference outputs
Input Address
CPU
PCI0:5
(MHz)
Spread
Spectrum
FS3 FS2 FS1 FS0
(MHz)
133.3
75
1
1
1
1
1
1
1
1
0
0
0
0
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
0
0
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
33.3
37.5
33.3
33.4
39.5
36.7
38.3
30
±0.5%
±0.5%
±0.5%
±0.5%
OFF
100.2
66.8
79
• Thirteen SDRAM outputs provide support for 3 DIMMs
• Supports frequencies up to 200 MHz
2
• I C™ interface for programming
110
OFF
• Power management control inputs
• Available in 48-pin SSOP
115
OFF
120
OFF
Key Specifications
133.3
83.3
100.2
66.8
124
33.3
27.7
33.3
33.4
31.0
32.3
34.5
35.8
OFF
OFF
CPU to CPU Output Skew: ......................................... 175 ps
PCI to PCI Output Skew: ............................................ 500 ps
OFF
OFF
V
: .................................................................... 3.3V±5%
DDQ3
OFF
129
OFF
138
OFF
143
OFF
Pin Configuration[1]
Block Diagram
VDDQ3
REF0/(CPU_STOP#)
REF1/FS0
VDDQ3
REF0/(CPU_STOP#)
GND
48
47
46
45
44
43
42
41
40
39
38
37
36
35
34
33
32
31
30
29
28
27
26
25
REF1/FS0*
GND
CPUT_CS
GND
CPUC0
CPUT0
VDDQ3
PWRDWN#*
SDRAM12
GND
SDRAM0
SDRAM1
VDDQ3
SDRAM2
SDRAM3
GND
SDRAM4
SDRAM5
VDDQ3
SDRAM6
SDRAM7
VDDQ3
48MHz/FS2*
24_48MHz/FS3^
1
X1
X2
XTAL
OSC
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
PLL Ref Freq
X1
I/O Pin
Control
X2
VDDQ3
PCI0/MODE
PCI1/FS1*
GND
PWRDWN#
CPUT_CS
PCI2
PCI3
PCI4
Stop
Clock
CPUT0
CPUC0
PCI5
PLL 1
Control
VDDQ3
SDRAMIN
GND
÷2,3,4
VDDQ3
PCI0/MODE
PCI1/FS1
PCI2
SDRAM11
SDRAM10
VDDQ3
SDRAM9
SDRAM8
GND
PCI3
PCI4
PCI5
2
SDATA
I C
{
2
SCLK
SDATA
SCLK
I C
Logic
VDDQ3
48MHz/FS2
PLL2
Note:
÷2
1. Internal pull-up resistors should not be relied upon for setting I/O
pins HIGH. Pin function with parentheses determined by MODE pin
resistor strapping. Unlike other I/O pins, input FS3 has an internal
pull-down resistor.
24_48MHz/FS3
VDDQ3
SDRAM0:12
SDRAMIN
13
I2C is a trademark of Philips Corporation.
Cypress Semiconductor Corporation
•
3901 North First Street
•
San Jose
•
CA 95134
•
408-943-2600
April 11, 2000, rev. *C