MC100H642FN

Overview

The MC100H642FN is a clock driver and distribution IC designed for 68030/040 microprocessors. It accepts ECL or TTL inputs and provides eight differential TTL outputs with a 2:8 input-to-output ratio. Operating on a single +5.0 V supply, it features internal divide-by-two and divide-by-four stages to generate required MPU clocks. The device ensures part-to-part skew within 2.0 ns and within-device skew within 1.0 ns at maximum frequencies up to 100 MHz. It is housed in a 28-PLCC package.

Feature Summary

• Generates necessary clocks for 68030/040 MPUs with guaranteed skew specifications
• Accepts both TTL and PECL (ECL referenced to +5.0 V) input sources
• Includes asynchronous reset and extra power/ground pins for stability
• Provides differential TTL outputs with internal ÷2 and ÷4 frequency division

Applications

• Clock generation for Motorola 68030 microprocessors
• Clock generation for Motorola 68040 microprocessors
• High-speed clock distribution systems requiring low skew

Procurement Notes

Verify the specific ordering suffix against the manufacturer's current documentation. The 'FN' suffix indicates a standard PLCC-28 rail package containing 37 units. Confirm RoHS compliance status, as non-compliant versions exist alongside Pb-Free alternatives like the FNG suffix. Ensure the selected variant matches the required packaging format for the assembly process.

Selection Notes

Select the MC100H642FN when interfacing with 100K logic levels referenced to +5.0 V. Use this component if the design requires synchronous positive edges of the ÷2 and ÷4 outputs upon power-up. Choose the FN suffix specifically for bulk rail mounting applications rather than tape-and-reel processes.

Part Context

This component belongs to the MC10H/100H642 family of clock drivers. The MC100H variant is specifically compatible with 100K logic levels, whereas the MC10H version supports MECL 10H™ levels. Both variants share identical pinouts and functional characteristics but differ in input voltage threshold compatibility.

Replacement Considerations

The MC10H642FN serves as a direct functional substitute for the MC100H642FN in designs utilizing MECL 10H™ logic levels instead of 100K levels. Verify that the input signal levels match the specific series requirements before swapping between these two part numbers.