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ICS950910 Datasheet, PDF (1/20 Pages) Integrated Circuit Systems – Programmable Timing Control Hub for P4
Integrated
Circuit
Systems, Inc.
ICS950910
Programmable Timing Control Hub™ for P4™
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 - 48MHz @ 3.3V fixed
• 1 - 24_48MHz @ 3.3V
• 2 - REF @ 3.3V, 14.318MHz
Key Specifications:
• CPU_CS - CPUT/C: <±250ps
• CPU_CS - AGP: <±250ps
• CPU - DDR: <±250ps
• PCI - PCI: <500ps
• CPU - PCI: Min = 1.0ns, Typ = 2.0ns, Max = 4.0ns
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 I2C Index read/write and block read/write
operations.
• Uses external 14.318MHz crystal.
Frequency Table
Bit2 Bit7 Bit6 Bit5 Bit4
FS3 FS2 FS1 FS0
CPU
MHz
1
0
0
0
0 105.00
1
0
0
0
1 140.00
1
0
0
1
0 210.00
1
0
0
1
1 174.99
1
0
1
0
0 80.00
1
0
1
0
1 106.66
1
0
1
1
0 160.00
1
0
1
1
1 133.33
1
1
1
0
0 100.00
1
1
1
0
1 133.33
1
1
1
1
0 200.00
1
1
1
1
1 166.66
1
1
0
0
0 100.00
1
1
0
0
1 133.33
1
1
0
1
0 200.00
1
1
0
1
1 166.66
AGP
MHz
70.00
70.00
70.00
70.00
53.34
53.34
53.34
53.34
66.67
66.67
66.67
66.67
66.67
66.67
66.67
66.67
PCI
MHz
35.00
35.00
35.00
35.00
26.66
26.66
26.66
26.66
33.33
33.33
33.33
33.33
33.33
33.33
33.33
33.33
Spread %
0.3 % Center Spread
0.3 % Center Spread
0.3 % Center Spread
0.3 % Center Spread
0.3 % Center Spread
0.3 % Center Spread
0.3 % Center Spread
0.3 % Center Spread
0.3 % Center Spread
0.3 % Center Spread
0.3 % Center Spread
0.3 % Center Spread
0 - 0.6% Down Spread
0 - 0.6% Down Spread
0 - 0.6% Down Spread
0 - 0.6% Down Spread
MULTISEL0
Board Target
Trace/Term Z
0
50 ohms
1
50 ohms
Reference R,
Iref =
VDD/(3*Rr)
Rr = 221 1%,
Iref = 5.00mA
Rr = 475 1%,
Iref = 2.32mA
Output
Current
Voh @ Z
Ioh = 4* I REF 1.0V @ 50
Ioh = 6* I REF 0.7V @ 50
0735A—03/18/04
Pin Configuration
*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
***PCICLK1 11
46 FBOUT
*MULTSEL/PCICLK2 12
45 BUF_IN
GNDPCI 13
44 DDRT0
PCICLK3 14
43 DDRC0
PCICLK4 15
42 DDRT1
VDDPCI 16
41 DDRC1
PCICLK5 17
40 VDD2.5
*(CLK_STOP#)PCICLK6 18
39 GND
GND48 19
38 DDRT2
*FS3/48MHz 20
37 DDRC2
*FS2/24_48MHz 21
36 DDRT3
AVDD48 22
35 DDRC3
VDD 23
34 VDD2.5
GND 24
33 GND
IREF 25
32 DDRT4
*(PD#)RESET# 26
31 DDRC4
SCLK 27
30 DDRT5
SDATA 28
29 DDRC5
56-SSOP
* Internal Pull-Up Resistor
** Internal Pull-Down Resistor
*** A 120k pull-down resistor to GND is needed on this pin.
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