ICS9248-112

Integrated Circuit Systems, Inc. ICS9248-112 Preliminary Product Preview Frequency Generator & Integrated Buffers for Celeron & PII/III™ Recommended Application: 810/810E type chipset. Output Features: 2- CPUs @2.5V, up to 150MHz. 9 - SDRAM @ 3.3V, up to150MHz including 1 free running 8 - PCICLK @ 3.3V 1 - IOAPIC @ 2.5V, PCI or PCI/2 MHz 2 - 3V66MHz @ 3.3V, 2X PCI MHz 1- 48MHz, @3.3V fixed. 1- 24MHz, @3.3V fixed 1- REF @3.3V, 14.318MHz. Features: Up to 166MHz frequency support Support FS0-FS3 strapping status bit for I2C read back. Support power management: Through Power down Mode from I2C programming. Spread spectrum for EMI control ( ± 0.25% center). Spread can be enabled or disabled to all 32 frequencies throuth I2C. Uses external 14.318MHz crystal Skew Specifications: CPU – CPU: <175ps SDRAM - SDRAM: < 250ps 3V66 – 3V66: <175ps PCI – PCI: <500ps CPU-SDRAM<500ps For group skew specifications, please refer to group timing relationship. Pin Configuration 48-Pin 300mil SSOP * These inputs have a 120K pull up to VDD. 1 These are double strength. Block Diagram Functionality FS3 FS2 FS1 FS0 CPU (MHz) SDRAM (MHz) 3V66 (MHz) PCICLK (MHz) I OA P I C 1=PCICLK/2 I OA P I C 0=PCICLK (MHz) (MHz) 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 0 0 0 0 1 1 1 1 0 0 0 0 1 1 1 1 0 0 1 1 0 0 1 1 0 0 1 1 0 0 1 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 66.80 68.00 100.30 103.00 133.73 145.00 133.73 137.33 140.00 140.00 118.00 124.00 133.70 137.00 150.00 72.50 100...