ICS9248-98 Datasheet, PDF (1/15 Pages) Integrated Circuit Systems – Frequency Generator & Integrated Buffers for Celeron & PII/III™

Integrated
Circuit
Systems, Inc.
ICS9248-98
Frequency Generator & Integrated Buffers for Celeron & PII/III™
Recommended Application:
440BX/VIA Apollo 133 style chipset.
Output Features:
• 2 - CPUs @2.5V, up to 166MHz.
• 1 - IOAPIC @ 2.5V
• 13 - SDRAM @ 3.3V
• 6 - PCI @3.3V,
• 1 - 48MHz, @3.3V fixed.
• 1 - 24MHz @ 3.3V
• 2 - REF @3.3V, 14.318MHz.
Features:
• Up to 166MHz frequency support
• Support power management: PCI, CPU stop and Mode
• Spread spectrum for EMI control (0 to -0.5%, ± 0.25%).
• Uses external 14.318MHz crystal
Skew Specifications:
• CPU – CPU: <175ps
• SDRAM - SDRAM: <250ps
• PCI – PCI: <500ps
• BUFFER_IN-SDRAM: <5ns
• CPU(early)-PCI: Min=1.0ns, Typ=2.3ns, Max=4.0ns
Pin Configuration
VDD1
1
*PCI_STOP/REF0
2
GND
3
X1
4
X2
5
VDD2
6
*MODE/PCICLK_F
7
**FS3/PCICLK0
8
GND
9
PCICLK1
10
PCICLK2
11
PCICLK3
12
PCICLK4
13
VDD2
14
BUFFER IN
15
GND
16
SDRAM11
17
SDRAM10
18
VDD3
19
SDRAM9
20
SDRAM8
21
GND
22
SDATA
23
SCLK
24
48
VDDL1
47
IOAPIC
46
REF1/FS2*
45
GND
44
CPUCLK_F
43
CPUCLK1
42
VDDL2
41
CLK_STOP#*
40
SDRAM_F
39
GND
38
SDRAM0
37
SDRAM1
36
VDD3
35
SDRAM2
34
SDRAM3
33
GND
32
SDRAM4
31
SDRAM5
30
VDD3
29
SDRAM6
28
SDRAM7
27
VDD4
26
48MHz/FS0*
25
24MHz/FS1*
48-Pin 300mil SSOP
* Internal Pull-up Resistor of 120K to VDD
** Internal Pull-down resistor of 120K to GND
Block Diagram
X1
X2
BUFFER IN
FS(3:0) ⁴
MODE
CLK_STOP#
PCI_STOP#
SDATA
SCLK
PLL2
/2
XTAL
OSC
STOP
PLL1
Spread
Spectrum
LATCH
4
POR
Control
Logic
Config.
Reg.
STOP
STOP
PCI
CLOCK
DIVDER
STOP
48MHz
24MHz
IOAPIC
2 ^REF(1:0)
CPUCLK_F
CPUCLK 1
12 ^{SDRAM (11:0)}
SDRAM_F
PCICLK (4:0)
5
PCICLKF
Functionality
FS3 FS2 FS1 FS0
0
0
0
0
0
0
0
1
0
0
1
0
0
0
1
1
0
1
0
0
0
1
0
1
0
1
1
0
0
1
1
1
1
0
0
0
1
0
0
1
1
0
1
0
1
0
1
1
1
1
0
0
1
1
0
1
1
1
1
0
1
1
1
1
CPU
(MHz)
80.00
75.00
83.31
66.82
103.00
112.01
68.01
100.23
120.00
114.99
109.99
105.00
140.00
150.00
124.00
132.99
PCICLK
(MHz)
40.00
37.50
41.65
33.41
34.33
37.34
34.01
33.41
40.00
38.33
36.66
35.00
35.00
37.50
31.00
33.25
9248-98 Rev D 11/6/00
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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.