General Description

The ICS9248-55 is a Clock Synthesizer chip for Pentium and PentiumPro CPU based Desktop/Notebook systems that will provide all necessary clock timing.

Features

• Generates system clocks for CPU, IOAPIC, PCI, plus

14.314 MHz REF (0:2), USB, and Super I/O

• Supports single or dual processor systems

• Supports Spread Spectrum modulation for CPU & PCI

clocks, down spread -0.5

• Skew from CPU (earlier) to PCI clock (rising edges for

100/33.3MHz) 1.5 to 4ns

• Two fixed outputs at 48MHz.

• Separate 2.5V and 3.3V supply pins

• 2.5V or 3.3V output: CPU, IOAPIC

• 3.3V outputs: PCI, REF, 48MHz

• No power supply sequence requirements

• Uses external 14.318MHz crystal, no external load cap

required for CL=18pF crystal

• 48 pin 300 mil SSOP