74ACT138SC

Signal Switches, Multiplexers, Decoders Overview

The Fairchild Semiconductor 74ACT138SC is a high-speed CMOS decoder/demultiplexer belonging to the 74ACT logic series. It features a single 3-to-8 line decoding circuit with active-low outputs in a 16-pin SOIC package. The device operates on a single power supply ranging from 4.5V to 5.5V and supports surface-mount installation. It functions within an industrial temperature range of -40°C to +85°C, providing TTL-compatible inputs for reliable interfacing in digital systems.

Signal Switches, Multiplexers, Decoders Feature Summary

• Provides one 3-to-8 line decoder/demultiplexer circuit with inverted outputs
• Features TTL-compatible inputs for direct interface with standard logic families
• Includes three enable inputs (two active-low, one active-high) to facilitate cascading applications

Signal Switches, Multiplexers, Decoders Applications

• Memory address decoding in computer systems
• Data routing and distribution networks
• Industrial control system signal selection

Signal Switches, Multiplexers, Decoders Procurement Notes

Verify the manufacturer designation as Fairchild Semiconductor or its successor entity, noting that Fairchild was acquired by onsemi. Confirm the specific suffix 'SC' corresponds to the SOIC-16 tube packaging variant rather than tape-and-reel formats. Ensure RoHS compliance status matches current regulatory requirements for the production batch.

Signal Switches, Multiplexers, Decoders Selection Notes

Select this component when a 3-to-8 decoder with active-low outputs is required in a surface-mount design. The ACT series offers speed comparable to LS-TTL with CMOS power consumption. Verify that the 16-SOIC footprint fits the PCB layout constraints and that the voltage levels align with the system's 5V logic domain.

Signal Switches, Multiplexers, Decoders Part Context

This part belongs to the 74ACT family of advanced CMOS logic devices, designed to bridge the performance gap between standard CMOS and low-power Schottky TTL. The 74ACT138 specifically addresses the need for fast, low-power decoding solutions in embedded and computing architectures where pin count and board space are critical factors.

Signal Switches, Multiplexers, Decoders Replacement Considerations

Direct substitutes include MC74ACT138DR2G from onsemi, which shares identical logical functionality but differs in reel packaging. Other compatible variants within the 74ACT138 family may be considered if pinout and electrical specifications match exactly.