ICS9155C-01CW20

Overview

The ICS9155C-01CW20 is a low-cost frequency generator designed for desktop and notebook PC applications, supporting 3.3V or 5.0V power supplies. It utilizes a 14.318 MHz crystal input to generate CPU clocks for 286, 386, and 486 systems. The device features an internal loop filter, skew-controlled 2x and 1x CPU clocks, and output enable functionality that tristates outputs. It supports turbo modes and generates communication, keyboard, floppy disk, system reference, bus, and CPU clocks. Maximum frequency reaches 220MHz with a 1:8 input-to-output ratio in a 20-SOIC package.

Feature Summary

• Compatible with 286, 386, and 486 CPUs
• Internal loop filter components reduce external component count
• Skew-controlled 2x and 1x CPU clock outputs
• Output enable tristates outputs when disabled

Applications

• Integrated desktop motherboards
• Notebook PC systems
• Legacy CPU clock generation (286/386/486)

Procurement Notes

Verify the manufacturer designation, as this part number originates from Integrated Circuit Systems (ICS), which was acquired by Renesas Electronics Corporation. Confirm the specific suffix CW20 corresponds to the 20-SOIC package and commercial temperature range (0°C ~ 70°C) in official documentation before procurement.

Selection Notes

Select this component for legacy PC architectures requiring multiple clock signals from a single 14.318 MHz crystal source. Ensure the design supports the 3V to 5.5V supply voltage range. The 1:8 frequency ratio and 220MHz maximum output must align with the target processor's requirements.

Part Context

This device belongs to the AV9155C series of low-cost frequency generators. It serves as a replacement for discrete oscillator solutions in older PC designs, consolidating multiple clock functions into a single IC to save board space and cost.

Replacement Considerations

Direct replacements include other variants within the AV9155C series, such as the AV9155C-44CW20, provided the pinout and electrical characteristics remain compatible with the existing motherboard layout.