ICS9248-146 Datasheet, PDF (1/16 Pages) Integrated Circuit Systems – Frequency Generator & Integrated Buffers for Celeron & PII/III™

Integrated
Circuit
Systems, Inc.
ICS9248-146
Frequency Generator & Integrated Buffers for Celeron & PII/III™
Recommended Application:
Single chip clock solution for SIS630S chipsets.
Output Features:
• 3- CPUs @ 2.5V
• 13 - SDRAM @ 3.3V
• 6- PCI @3.3V,
• 2 - AGP @ 3.3V
• 1- 48MHz, @3.3V fixed.
• 1- 24/48MHz, @3.3V selectable by I²C
(Default is 24MHz)
• 2- REF @3.3V, 14.318MHz.
Features:
• Up to 166MHz frequency support
• Support FS0-FS3 trapping status bit for I²C read back.
• Support power management: CPU, PCI, SDRAM stops
and Power down Mode form I²C programming.
• Spread spectrum for EMI control (0 to -0.5%, ± 0.25%).
• Uses external 14.318MHz crystal
Skew Specifications:
• CPU - CPU: < 175ps
• SDRAM - SDRAM < 250ps (except SDRAM12)
• PCI - PCI: < 500ps
• CPU (early) - PCI: 1-4ns (typ. 2ns)
Pin Configuration
VDDA
1
1_{*(AGPSEL)REF0}
2
1_*(FS3)REF1
3
GND
4
X1
5
X2
6
VDDPCI
7
*(FS1)PCICLK_F
8
*(FS2)PCICLK0
9
PCICLK1
10
PCICLK2
11
PCICLK3
12
PCICLK4
13
GND
14
VDDAGP
15
AGPCLK0
16
AGPCLK1
17
GND
18
GND
19
*(FS0)48MHz
20
*(MODE)24_48MHz
21
VDD48
22
SDATA
23
SCLK
24
48 VDDL
47 CPUCLK0
46 CPUCLK1
45 CPUCLK2
44 GND
43 VDDSDR
42 SDRAM0
41 SDRAM1
40 SDRAM2
39 GND
38 SDRAM3
37 SDRAM4
36 SDRAM5
35 VDDSDR
34 SDRAM6
33 SDRAM7
32 GND
31 SDRAM8/PD#
30 SDRAM9/SDRAM_STOP#
29 GND
28 SDRAM10/PCI_STOP#
27 SDRAM11/CPU_STOP#
26 SDRAM12
25 VDDSDR
48-Pin 300mil SSOP
* These inputs have a 120K pull down to GND.
1 _{These are double strength.}
Block Diagram
PLL2
X1
XTAL
X2
OSC
PLL1
Spread
Spectrum
SDATA
SCLK
FS(3:0)
PD#
PCI_STOP#
CPU_STOP#
SDRAM_STOP#
MODE
AGP_SEL
Control
Logic
Config.
Reg.
/2
CPU
DIVDER
Stop
SDRAM
DIVDER
Stop
PCI
DIVDER
Stop
AGP
DIVDER
Functionality
48MHz
24_48MHz
REF(1:0)
2
3 ^{CPUCLK (2:0)}
SDRAM (12:0)
13
5 ^{PCICLK (4:0)}
PCICLK_F
AGP (1:0)
2
FS3 FS2 FS1 FS0
CPU
SDRAM
PCICLK
AGP SEL
=0
AGP SEL
=1
0 0 0 0 66.67 66.67 33.33 66.67 50.00
0 0 0 1 100.00 100.00 33.33 66.67 50.00
0 0 1 0 166.67 166.67 33.33 66.66 55.56
0 0 1 1 133.33 133.33 33.33
0 1 0 0 66.67 100.00 33.33
0 1 0 1 100.00 66.67 33.33
0 1 1 0 100.00 133.33 33.33
0 1 1 1 133.33 100.00 33.33
1 0 0 0 112.00 112.00 33.60
1 0 0 1 124.00 124.00 31.00
66.67
66.67
66.67
66.67
66.67
67.20
62.00
50.00
50.00
50.00
50.00
50.00
56.00
46.50
1 0 1 0 138.00 138.00 34.50 69.00 51.75
1 0 1 1 150.00 150.00 30.00 60.00 50.00
1 1 0 0 66.67 133.33 33.33
1 1 0 1 100.00 150.00 30.00
1 1 1 0 150.00 100.00 30.00
1 1 1 1 160.00 120.00 30.00
66.67
60.00
60.00
60.00
50.00
50.00
50.00
48.00
9248-146 RevA- 4/23/01
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ICS reserves the right to make changes in the device data identified in
this publication without further notice. ICS advises its customers to
obtain the latest version of all device data to verify that any
information being relied upon by the customer is current and accurate.