ICS9248-97 Datasheet, PDF (1/14 Pages) Integrated Circuit Systems – Frequency Timing Generator for PENTIUM II Systems

Integrated
Circuit
Systems, Inc.
ICS9248-97
Frequency Timing Generator for PENTIUM II Systems
Recommended Application:
Camino chipset
Output Features:
• 3 - CPUs @ 2.5V, up to 180MHz.
• 3 - IOAPIC @ 2.5V, PCI/2
• 3 - 3V66MHz @ 3.3V.
• 11 - PCIs @ 3.3V
• 1 - 48MHz, @ 3.3V fixed
• 1 - 24/48MHz, @ 3.3V
• 1 - CPU/2, @ 2.5V.
Features:
• Up to 180MHz frequency support
• Support power management: Power down Mode
from I²C programming.
• Spread spectrum for EMI control
± 0.25% center spread).
• Uses external 14.318MHz crystal
• FS pins for frequency select
Key Specifications:
• CPU Output Jitter: <250ps
• CPU/2 Output Jitter. <250ps
• IOAPIC Output Jitter: <500ps
• 48MHz, 3V66, PCI Output Jitter: <500ps
• Ref Output Jitter. <1000ps
• CPU Output Skew: <175ps
• IOAPIC Output Skew <250ps
• 3V66 Output Skew <250ps
• CPU to 3V66 Output Offset: 0.0 - 1.5ns (CPU leads)
• 3V66 to PCI Output Offset: 1.5 - 4.0ns (3V66 leads)
• CPU to IOAPIC Output Offset 1.5 - 4.0ns (CPU leads)
Pin Configuration
GNDREF
1
REF0
2
*SEL24_48#/REF1
3
VDDREF
4
X1
5
X2
6
GNDPCI
7
*FS0/PCICLK_F
8
*FS1/PCICLK0
9
VDDPCI
10
*FS2/PCICLK1
11
*FS3/PCICLK2
12
GNDPCI
13
PCICLK3
14
PCICLK4
15
VDDPCI
16
PCICLK5
17
PCICLK6
18
GNDPCI
19
PCICLK7
20
PCICLK8
21
PCICLK9
22
VDDPCI
23
PD#
24
48
VDDLAPIC
47
IOAPIC0
46
IOAPIC1
45
GNDLAPIC
44
IOAPIC2
43
VDDLCPU/2
42
CPU/2
41
GNDLCPU/2
40
CPUCLK0
39
VDDLCPU
38
CPUCLK1
37
CPUCLK2
36
GNDLCPU
35
VDD66
34
3V66_0
33
3V66_1
32
3V66_2
31
GND66
30
SDATA
29
SCLK
28
VDD48
27
48MHz/FS4*
26
24_48MHz
25
GND48
48-pin SSOP
*120K ohm pull-up to VDD on indicated inputs.
Block Diagram
PLL2
X1
XTAL
X2
OSC
PLL1
Spread
Spectrum
SEL24_48#
SDATA
SCLK
FS (4:0)
PD#
Control
Logic
Config.
Reg.
/2
CPU
DIVDER
/2
IOAPIC
DIVDER
PCI
DIVDER
3V66
DIVDER
48MHz
24_48MHz
REF (1:0)
CPUCLK (2:0)
CPU/2
IOAPIC (2:0)
PCICLK (9:0)
PCICLK_F
3V66 (2:0)
9248-97 Rev E 08/18/00
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.