SN74F138NS

Overview

The SN74F138NS is a high-speed silicon-gate CMOS decoder/demultiplexer manufactured by Texas Instruments. It features a 16-pin SOIC surface-mount package and operates within a supply voltage range of 4.5 V to 5.5 V. The device functions as a 3-to-8 line decoder with active-low outputs, utilizing three address inputs and three enable inputs for chip selection. Designed for the F-series logic family, it supports operation temperatures from 0°C to +70°C, ensuring reliable performance in standard commercial electronic applications requiring fast switching speeds.

Feature Summary

• Provides decoding functionality for converting three binary address inputs into one of eight active-low output lines
• Incorporates three independent enable inputs that must be satisfied simultaneously to activate the selected output
• Utilizes high-speed silicon-gate CMOS technology to achieve rapid signal propagation and low power consumption

Applications

• Address decoding in microprocessor-based memory systems
• Demultiplexing data streams in digital communication circuits
• Control logic implementation in industrial automation equipment

Procurement Notes

Verify the specific suffix 'NS' against the manufacturer's official documentation to confirm the exact package variant and tape-and-reel specifications. Ensure compatibility with existing PCB footprints for the 16-pin SOIC form factor. Cross-reference the revision history to confirm lead-free compliance and RoHS status prior to final procurement approval.

Selection Notes

Select this component when high-speed switching is required alongside standard 5V logic levels. The F-series offers superior speed compared to HC or HCT variants. Verify that the operating temperature range meets the environmental requirements of the target application. Confirm that the 16-pin SOIC package aligns with the available assembly capabilities and board space constraints.

Part Context

This part belongs to the Texas Instruments SN74F series, which represents high-speed CMOS logic. The 138 designation indicates a 3-to-8 decoder architecture. The NS suffix typically denotes a specific plastic small-outline package configuration. This series is widely used in legacy and modern digital designs requiring fast propagation delays.

Replacement Considerations

Compatible substitutes include the SN74F138D (SOIC-16) and SN74F138N (PDIP-16). Verify pinout compatibility and electrical characteristics before substitution.