W144
440BX AGPset Spread Spectrum Frequency Synthesizer
Features
Table 1. Pin Selectable Frequency
Input Address
FS3 FS2 FS1 FS0
• Maximized electromagnetic interference (EMI)
suppression using Cypress’ Spread Spectrum
technology
• Single chip system frequency synthesizer for Intel®
440BX AGPset
CPU_F, CPU1
(MHz)
PCI_F, 1:5 (MHz)
33.4 (CPU/4)
31 (CPU/4)
37.5 (CPU/4)
35 (CPU/4)
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
133.6
124
150
140
105
110
• Two copies of CPU output
• Six copies of PCI output 1
• One 48-MHz output for USB
• One 24-MHz output for SIO
• Two buffered reference outputs
• One IOAPIC output
35 (CPU/3)
36.7 (CPU/3)
38.3 (CPU/3)
40 (CPU/3)
115
120
100.2
133.3
112
103
66.8
83.3
75
33.4 (CPU/3)
44.43 (CPU/3)
37.3 (CPU/3)
34.3 (CPU/3)
33.4 (CPU/2)
41.7 (CPU/2)
37.5 (CPU/2)
41.3 (CPU/3)
• Thirteen SDRAM outputs provide support for three
DIMMs
• Supports frequencies up to 150 MHz
• I2C interface for programming
• Power management control inputs
124
Pin Configuration[1]
Logic Block Diagram
VDDQ3
VDDQ3
REF0/(PCI_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
VDDQ2
1
REF0/(PCI_STOP#)
REF1/FS2
IOAPIC
2
REF1/FS2*
GND
CPU_F
CPU1
VDDQ2
CLK_STOP#
SDRAM_F
GND
SDRAM0
SDRAM1
VDDQ3
SDRAM2
SDRAM3
GND
SDRAM4
SDRAM5
VDDQ3
3
X1
X2
XTAL
OSC
X1
4
PLL Ref Freq
X2
5
VDDQ2
IOAPIC
VDDQ3
PCI_F/MODE
**PCI1/FS3
GND
6
Stop
Clock
I/O Pin
Control
7
Control
8
9
PCI2
PCI3
PCI4
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
CLK_STOP#
VDDQ2
Stop
Clock
Control
CPU1
PCI5
PLL 1
÷2,3,4
VDDQ3
SDRAMIN
GND
CPU_F
VDDQ3
PCI_F/MODE
PCI1/FS3
PCI2
SDRAM11
SDRAM10
VDDQ3
SDRAM9
SDRAM8
GND
Stop
Clock
SDRAM6
SDRAM7
VDDQ3
48MHz/FS0*
24MHz/FS1*
PCI3
Control
PCI4
PCI5
2
SDATA
I C
{
2
SDATA
SCLK
I C
Logic
SCLK
VDDQ3
48MHz/FS0
PLL2
÷2
24MHz/FS1
VDDQ3
Stop
Clock
Control
SDRAMIN
SDRAM0:11
12
SDRAM_F
Note:
1. * Has an internal pull-up resistors. It should not be relied upon for setting I/O pins HIGH. Pin function with parentheses determined by MODE pin resistor strapping
while ** has an internal pull down resistor.
Cypress Semiconductor Corporation
Document #: 38-07153 Rev. *B
•
3901 North First Street
•
San Jose, CA 95134
•
408-943-2600
Revised January 16, 2004