MC74AC139N

Overview

The MC74AC139N is a high-speed dual 1-of-4 decoder/demultiplexer manufactured by onsemi. It contains two independent decoders, each accepting two binary weighted address inputs (A0-A1) and providing four mutually exclusive active-LOW outputs (O0-O3). Each decoder features an active-LOW enable input that can function as a data input for demultiplexing applications. The device operates within a supply voltage range of 2.0 V to 6.0 V and supports output currents of ±24 mA. It is housed in a 16-lead PDIP package.

Feature Summary

• Contains two completely independent 1-of-4 decoders with active-LOW mutually exclusive outputs.
• Enable inputs support demultiplexer functionality by acting as data inputs.
• Outputs are capable of sourcing and sinking 24 mA current.
• Generates all four minterms of two variables for logic function generation.

Applications

• Address decoding in microprocessor systems
• Data distribution via demultiplexing operations
• Logic function generation replacing multiple discrete gates

Procurement Notes

Verify the specific ordering suffix 'N' corresponds to the PDIP-16 package configuration required for your design. Confirm RoHS compliance status for the specific batch if environmental regulations apply. Ensure the selected component matches the AC logic family specifications rather than the ACT variant which has different input thresholds. Cross-reference the datasheet revision date against your manufacturing timeline.

Selection Notes

Select this component when a dual decoder or demultiplexer solution is required within a single package. It is suitable for designs needing active-LOW outputs and moderate drive capability. Consider the PDIP-16 package constraints regarding board space and thermal dissipation. Verify that the 2V to 6V operating voltage range aligns with the system power rails.

Part Context

This part belongs to the MC74AC139/74ACT139 series of high-speed CMOS logic devices. The 'AC' designation indicates standard AC logic characteristics, distinct from the 'ACT' version which offers TTL-compatible inputs. The N suffix specifically denotes the plastic dual-in-line package format, distinguishing it from SOIC or TSSOP variants.

Replacement Considerations

MC74ACT139N: Offers TTL-compatible inputs but requires a 4.5V to 5.5V supply range. MC74AC139D: Same electrical performance but utilizes an SOIC-16 surface-mount package instead of through-hole DIP.