MC74ACT139D

Overview

The MC74ACT139D is a high-speed dual 1-of-4 decoder/demultiplexer from the 74ACT logic series, manufactured by onsemi. It features two independent decoders, each accepting two binary weighted address inputs (A0-A1) and providing four mutually exclusive active-LOW outputs (O0-O3). Each decoder includes an active-LOW enable input that can function as a data input for demultiplexing applications. The device operates within a supply voltage range of 4.5 V to 5.5 V and supports TTL-compatible inputs. It is housed in a 16-lead SOIC package.

Feature Summary

• Contains two completely independent 1-of-4 decoders with active-LOW mutually exclusive outputs.
• Features TTL-compatible inputs for compatibility with standard logic families.
• Capable of functioning as a 4-output demultiplexer using the enable pin as a data input.
• Generates all four minterms of two variables for use as a function generator.

Applications

• Address decoding in digital systems
• Data distribution and demultiplexing
• Logic function generation replacing multiple discrete gates

Procurement Notes

Verify the specific ordering suffix 'D' corresponds to the SOIC-16 package configuration required for your design. Confirm RoHS compliance status and Pb-free availability through official onsemi channels or authorized distributors, as packaging options may vary. Ensure the component meets the recommended operating conditions for your target ambient temperature range.

Selection Notes

Select this component when a dual decoder solution is needed within a single package to reduce board space. The 74ACT series offers higher speed than standard 74LS devices while maintaining TTL input compatibility. Consider the SOIC-16 package dimensions against your PCB layout constraints and verify that the output current capabilities meet the load requirements of the connected circuitry.

Part Context

This part belongs to the MC74AC/ACT139 family of dual 1-of-4 decoders. The 'ACT' designation indicates CMOS technology with TTL-compatible input thresholds, bridging the gap between older bipolar logic and modern CMOS speeds. The 'D' suffix specifically identifies the plastic small-outline package variant.

Replacement Considerations

MC74ACT139DR2G