General Description

The ICS94228 is a main clock synthesizer chip for AMD-K7 based systems with VIA style chipset. This provides all clocks required for such a system.

Features:

• Programmable output frequency.

• Programmable output rise/fall time.

• Programmable slew and skew control for CPUCLK, PCICLK, AGP, REF, 48MHz and 24_48MHz.

• Real time system reset output.

• Spread spectrum for EMI control typically by 7dB to 8dB, with programmable spread percentage.

• Watchdog timer technology to reset system if over-clocking causes malfunction.

• Uses external 14.318MHz crystal.

Output Features:

• 1 - Differential pair open drain CPU clocks @ 2.7V

• 1 - Differential pair push-pull CPU clocks @ 2.5V

• 11 - PCI including 1 free running and 1 early @ 3.3V

• 1 - 48MHz, @ 3.3V fixed

• 1 - 24/48MHz @ 3.3V

• 3 - REF @ 3.3V, 14.318MHz.

Recommended Application:

VIA KT266 style chipset