MR8254/R

Overview

The MR8254/R is a programmable interval timer manufactured by Rochester Electronics, LLC. It utilizes advanced CHMOS III technology to provide three independent 16-bit counters within a single integrated circuit. The device supports six distinct programmable operating modes for flexible timing and counting applications. It operates with an external data bus width of 8 bits and accepts parallel direct address inputs. The component is rated for a maximum clock frequency of 8 MHz and functions within a supply voltage range of 4.5 V to 5.5 V, with a nominal rating of 5 V.

Feature Summary

• Incorporates three independent 16-bit counter/timer channels
• Supports six programmable operating modes for versatile timing control
• Utilizes advanced CHMOS III technology for low power consumption
• Features an 8-bit external data bus with parallel direct addressing

Applications

• General-purpose programmable interval timing circuits
• Digital system clock generation and division
• Event counting and pulse width measurement
• Timing control in embedded microcontroller systems

Procurement Notes

Verify the specific suffix configuration against the manufacturer's documentation to ensure compatibility with the required package type and temperature range. Confirm that the source is an authorized continuing source provider, as this component may be classified as end-of-life or obsolete. Request detailed electrical test data to validate performance parameters prior to integration into critical designs.

Selection Notes

Select this component when multiple independent 16-bit timers are required within a single package footprint. Ensure the design environment supports the specified 5 V logic levels and 8 MHz maximum clock speed. Consider the DIP package constraints if surface mount alternatives are not feasible. Verify thermal requirements against the -40 °C to 85 °C operating range for the intended application environment.

Part Context

Rochester Electronics specializes in lifecycle solutions for semiconductors, often serving as an authorized continuing source for components that have reached end-of-life status with original manufacturers. This part represents a continuation of legacy programmable timer technology, providing availability for systems requiring long-term component stability without redesigning around newer, incompatible interfaces.

Replacement Considerations

Direct functional substitutes include the Intel 8254 or equivalent industrial-grade programmable interval timers. Verify pinout compatibility and logic level alignment before substitution. Alternative packages such as LCC variants may exist but require careful evaluation of thermal and mechanical fit within the existing board layout.