DM74S139N

Overview

The DM74S139N is a dual 2-line-to-4-line decoder/demultiplexer manufactured by Fairchild Semiconductor. It operates within the Schottky TTL logic family and is housed in a 16-pin Plastic Dual-In-Line Package (PDIP). The device integrates two independent decoding circuits, each featuring an active-LOW enable input that can function as a data line for demultiplexing applications. All inputs are fully buffered and clamped with high-performance Schottky diodes to suppress line-ringing.

Feature Summary

• Integrates two independent 2-to-4-line decoders or demultiplexers within a single package
• Features Schottky clamping on all inputs to suppress line-ringing and simplify system design
• Includes active-LOW enable inputs that can serve as data lines for demultiplexing functions

Applications

• High-performance memory decoding systems
• Data routing applications requiring short propagation delays
• Data transmission systems

Procurement Notes

Verify the specific ordering code suffix against official documentation to confirm package type and availability options. Ensure the component matches the required Schottky TTL specifications for your circuit design. Confirm that the active-LOW enable functionality aligns with your system's control logic requirements before finalizing procurement.

Selection Notes

Select this component when designing systems that require multiple independent decoding channels without consuming excessive board space. The Schottky technology offers high-speed performance suitable for memory systems where decoder delay must be negligible compared to memory access times. Verify compatibility with existing TTL logic levels and power supply constraints.

Part Context

This part belongs to the DM74S series of Schottky TTL logic devices produced by Fairchild Semiconductor. It is often grouped with other decoders like the DM74S138 for complex addressing schemes. The series is characterized by its high speed and robust input protection features, making it suitable for demanding digital logic applications.

Replacement Considerations

Compatible substitutes include the DM74ALS139 and DM74LS139. Verify pinout compatibility and electrical characteristics such as propagation delay and drive current when substituting these variants.