SN74F138DR

Overview

The SN74F138DR is a 3-to-8 decoder/demultiplexer from Texas Instruments, part of the F logic series. It features a 16-pin SOIC package with surface mount installation. The device operates within a supply voltage range of 4.5 V to 5.5 V and supports an operating temperature range of 0°C to +70°C. Designed for high-performance memory decoding or data routing, it offers short propagation delays suitable for fast systems.

Feature Summary

• Designed for high-performance memory decoding and data routing applications requiring very short propagation delay times
• Integrates three enable inputs to simplify cascading and reduce external component requirements
• Outputs are capable of driving up to ten LSTTL loads

Applications

• High-performance memory decoding systems
• Data routing applications
• Industrial control systems

Procurement Notes

Verify the specific suffix 'DR' indicates tape-and-reel packaging when sourcing. Confirm the F-series logic family matches system speed requirements. Ensure the 16-pin SOIC footprint aligns with PCB layout constraints. Check that the 4.5V to 5.5V supply range fits the target circuit design.

Selection Notes

Select this component when low propagation delay is critical for memory access timing. The HC series offers wider voltage ranges but slower speeds; the LS series is slower. The F series provides a balance of speed and drive capability. Verify thermal limits for the specified industrial temperature range during selection.

Part Context

This part belongs to the standard 74xx logic family, specifically the F (Fast) sub-family. It serves as a digital logic interface for addressing and signal distribution. The DR suffix denotes reel packaging, distinguishing it from tube-packaged variants like the SN74F138D.

Replacement Considerations

The SN74HC138DR is a compatible alternative offering similar functionality with CMOS technology and a wider voltage range. The SN74LS138D provides comparable decoding but with different speed and power characteristics.