ICS94229 is a programmable system clock chip that supports AMD - K7™ processors and is suitable for VIA KT266-style chipsets. It features programmable output frequency, programmable output rise/fall time, programmable slew and skew control, real-time system reset output, EMI control, and watchdog timer technology.
The ICS94229 is a programmable system clock synthesizer designed for AMD‑K7 based systems with VIA KT266 style chipsets. It generates all required system clocks and offers programmable output frequency, spread spectrum, and watchdog timer features.
The device includes a 48‑pin SSOP package with a variety of configurable pins for CPU, PCI, AGP, and reference clocks. Registers can be programmed via a serial interface to control frequency, skew, rise/fall times, and spread spectrum. Detailed timing diagrams, pin descriptions, and register maps are provided for integration and debugging.
| Output frequency range | 1‑48 MHz @ 3.3 V |
|---|---|
| CPU clock output type | Differential pair open‑drain @ 2.5 V |
| PCI clock output type | Differential pair push‑pull @ 2.5 V |
| Power supply voltage | 3.3 V nominal |
| Watchdog reset pulse width | 288 ms |
| Spread spectrum reduction | 7 dB to 8 dB |
| CPU‑CPU skew | < 175 ps |
| PCI‑PCI skew | < 500 ps |
| Package type | 48‑pin 300 mil SSOP |
SRESET# is a real‑time active‑low pulse that resets the system; it drives low for a 288 ms pulse width.
All power pins are supplied with a nominal 3.3 V voltage.
The chip can reduce EMI by approximately 7 dB to 8 dB using spread‑spectrum control.