SN74HCT139N

Overview

The SN74HCT139N is a dual 2-line to 4-line decoder/demultiplexer from the Texas Instruments SN74HCT logic family. It features low input current and fully buffered inputs, with each input representing only one normalized load for its drive circuit. The device operates within a supply voltage range of 4.5 V to 5.5 V and supports through-hole mounting in a 16-pin PDIP package. It includes active-low enable inputs that can function as data lines in demultiplexing applications.

Feature Summary

• Dual independent 2-to-4 decoding circuits integrated into a single package
• HCT input compatibility ensures direct interface with TTL-driven systems
• Active-low enables allow flexible configuration for demultiplexing tasks

Applications

• Memory address decoding in digital systems
• Data distribution in transmission networks
• General-purpose logic control circuits

Procurement Notes

Verify the specific suffix 'N' confirms the PDIP through-hole package variant rather than surface-mount options. Confirm HCT series compatibility requirements match the system's voltage levels. Check for RoHS compliance status and ensure the manufacturer source is authorized to avoid counterfeit components.

Selection Notes

Select this component when TTL-compatible CMOS performance is required for decoding tasks. The HCT series provides noise margins suitable for industrial environments while maintaining low power consumption. Ensure the 16-pin DIP form factor fits the existing PCB layout constraints compared to SMD alternatives.

Part Context

This part belongs to the widely adopted SN74xx logic family, specifically the High-speed CMOS Technology (HCT) subset. It serves as a standard solution for basic binary decoding needs in consumer electronics and industrial control panels where reliable signal translation between logic families is necessary.

Replacement Considerations

SN74HC139N offers similar functionality but requires higher voltage levels for proper operation. SN54HCT139J provides military-grade temperature ranges for harsher environments. CD74HC139M is a surface-mount alternative requiring different footprint considerations.