ICS951412 Datasheet, PDF (1/19 Pages) Integrated Circuit Systems – System Clock Chip for ATI RS480 K8-based Systems

Integrated
Circuit
Systems, Inc.
ICS951412
System Clock Chip for ATI RS480 K8-based Systems
Recommended Application:
ATI RS480 systems using AMD K8 processors
Output Features:
• 3 - 14.318 MHz REF clocks
• 1 - USB_48MHz USB clock
• 1 - HyperTransport 66 MHz clock seed
• 1 - PCI 33 MHz clock seed
• 2 - Pairs of AMD K8 clocks
• 6 - Pairs of SRC/PCI Express* clocks
• 2 - Pairs of ATIG (SRC/PCI Express) clocks
Features:
• 2 - Programmable Clock Request pins for SRC
clocks
• Spread Spectrum for EMI reduction
• Outputs may be disabled via SMBus
• External crystal load capacitors for maximum
frequency accuracy
Pin Configuration
X1 1
X2 2
VDD48 3
USB_48MHz 4
GND 5
NC 6
SCLK 7
SDATA 8
**FS2 9
**CLKREQA# 10
**CLKREQB# 11
SRCCLKT7 12
SRCCLKC7 13
VDDSRC 14
GNDSRC 15
SRCCLKT6 16
SRCCLKC6 17
SRCCLKT5 18
SRCCLKC5 19
GNDSRC 20
VDDSRC 21
SRCCLKT4 22
SRCCLKC4 23
SRCCLKT3 24
SRCCLKC3 25
GNDSRC 26
ATIGCLKT1 27
ATIGCLKC1 28
56 VDDREF
55 GND
54 **FS0/REF0
53 **FS1/REF1
52 REF2
51 VDDPCI
50 PCICLK0
49 GNDPCI
48 VDDHTT
47 HTTCLK0
46 GNDHTT
45 CPUCLK8T0
44 CPUCLK8C0
43 VDDCPU
42 GNDCPU
41 CPUCLK8T1
40 CPUCLK8C1
39 VDDA
38 GNDA
37 IREF
36 GNDSRC
35 VDDSRC
34 SRCCLKT0
33 SRCCLKC0
32 VDDATI
31 GNDATI
30 ATIGCLKT0
29 ATIGCLKC0
Note: Pins preceeded by '**' have a 120 Kohm Internal Pull Down resistor
56 Pin SSOP/TSSOP
Power Groups
Pin Number
VDD
GND
56
55
51
49
48
46
43
14, 21,
32,35
39
42
15, 20,
26,31,36
38
3
5
0883G—12/08/04
Description
Xtal, REF
PCICLK output
HTTCLK output
CPU Outputs
SRC outputs
Analog, CPU PLL
USB_48MHz output
Functionality
FS2
FS1
FS0
0
0
0
0
0
1
0
1
0
0
1
1
1
0
0
1
0
1
1
1
1
CPU
MHz
Hi-Z
X
180.00
220.00
100.00
133.33
200.00
HTT
MHz
Hi-Z
X/3
60.00
73.12
66.66
66.66
66.66
PCI
MHz
Hi-Z
X/6
30.00
36.56
33.33
33.33
33.33
*Other names and brands may be claimed as the property of others.