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Integrated
Circuit
Systems, Inc.
ICS950902
0475F—10/13/03
Block Diagram
Pin Configuration
Recommended Application:
VIA P4X/P4M/KT/KN266/333 style chipsets.
Output Features:
1 - Pair of differential CPU clocks @ 3.3V (CK408)/
1 - Pair of differential open drain CPU clocks (K7)
1 - Pair of differential push pull CPU_CS clocks @ 2.5V
3 - AGP @ 3.3V
7 - PCI @ 3.3V (1 - Free running)
1 - 48MHz @ 3.3V fixed
1 - 24_48MHz @ 3.3V (Default 48MHz I
2C select only)
2 - REF @ 3.3V, 14.318MHz
12 - SDRAM (6 pair - DDR) selectable
Features/Benefits:
Programmable output frequency.
Programmable output divider ratios.
Programmable output rise/fall time.
Programmable output skew.
Programmable spread percentage for EMI control.
DDR output buffer supports up to 200MHz.
Watchdog timer technology to reset system
if system malfunctions.
Programmable watch dog safe frequency.
Support I
2C Index read/write and block read/write
operations.
Uses external 14.318MHz crystal.
Key Specifications:
CPU_CS - CPUT/C: <±250ps
CPU_CS - AGP: <±250ps
CPU - DDR/SD: <±250ps
PCI - PCI: <500ps
CPU - PCI: Min = 1.0ns, Typ = 2.0ns, Max = 4.0ns
Programmable Timing Control Hub for P4
* Internal 120K pull-up resistor to VDD.
** Internal 120K pull-down resistor to GND.
56-Pin 300-mil SSOP & 240-mil TSSOP
Frequency Table
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3
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3
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6
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6
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3
.
3
*FS0/REF0 1
56 Vtt_PWRGD#**/REF1
GND 2
55 VDDREF
X1 3
54 GND
X2 4
53 CPUCLKT/CPUCLKODT
VDDAGP 5
52 CPUCLKC/CPUCLKODC
*MODE/AGPCLK0 6
51 VDDCPU3.3
*SEL_408/K7/AGPCLK1 7
50 VDDCPU2.5
*(PCI_STOP#)AGPCLK2 8
49 CPUC_CS
GNDAGP 9
48 CPUT_CS
**FS1/PCICLK_F 10
47 GND
**SEL_SDR/DDR#/PCICLK1 11
46 FBOUT
*MULTSEL/PCICLK2 12
45 BUF_IN
GNDPCI 13
44 DDRT0/SDRAM0
PCICLK3 14
43 DDRC0/SDRAM1
PCICLK4 15
42 DDRT1/SDRAM2
VDDPCI 16
41 DDRC1/SDRAM3
PCICLK5 17
40 VDD3.3_2.5
*(CLK_STOP#)PCICLK6 18
39 GND
GND48 19
38 DDRT2/SDRAM4
*FS3/48MHz 20
37 DDRC2/SDRAM5
*FS2/24_48MHz 21
36 DDRT3/SDRAM6
AVDD48 22
35 DDRC3/SDRAM7
VDD 23
34 VDD3.3_2.5
GND 24
33 GND
IREF 25
32 DDRT4/SDRAM8
*(PD#)RESET# 26
31 DDRC4/SDRAM9
SCLK 27
30 DDRT5/SDRAM10
SDATA 28
29 DDRC5/SDRAM11
IC
S
950902
DDRC (5:0)/SDRAM (10,8,6,4,2,0)
DDRC (5:0)/SDRAM (11,9,7,5,3,1)
FBOUT