Overview

Description

The 94228 is a main clock synthesizer chip for AMD-K7 based systems with VIA style chipset. This provides all clocks required for such a system. The 94228 belongs to ICS new generation of programmable system clock generators. It employs serial programming I2C interface as a vehicle for changing output functions, changing output frequency, configuring output strength, configuring output to output skew, changing spread spectrum amount, changing group divider ratio and dis/ enabling individual clocks. This device also has ICS propriety 'Watchdog Timer' technology which will reset the frequency to a safe setting if the system become unstable from over clocking.

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.
  • 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.

Comparison

Applications

Documentation

Type Title Date
Product Change Notice PDF 361 KB
1 item

Design & Development

Models