CD74HCT138MT

Overview

The CD74HCT138MT is a high-speed silicon-gate CMOS decoder manufactured by Texas Instruments. It functions as a 1 x 3-to-8 line decoder/demultiplexer housed in a 16-SOIC surface-mount package. The device operates on a single power supply ranging from 4.5V to 5.5V and supports an extended industrial temperature range of -55°C to 125°C. It features three binary selection inputs (A0, A1, A2) and includes two active-low enable inputs and one active-high enable input to facilitate cascading applications.

Feature Summary

• Provides eight mutually exclusive outputs that are normally high and go low when selected
• Includes dedicated enable inputs to simplify cascading multiple decoders
• Offers direct compatibility with Low-Power Schottky TTL logic levels

Applications

• Memory address decoding systems
• Data routing and distribution networks
• I/O port selection circuits

Procurement Notes

Verify the specific suffix 'MT' against the manufacturer datasheet to confirm the exact tape-and-reel packaging configuration and moisture sensitivity level. Ensure the ordering part number matches the required SOIC package width and lead finish specifications for your assembly process.

Selection Notes

Select this component when a standard 3-to-8 decoding function is required within a 5V logic environment. It serves as a suitable alternative to HC series devices where direct LSTTL input compatibility is necessary without additional buffering.

Part Context

This part belongs to the Texas Instruments CD74HCT family of high-speed CMOS logic devices. It shares functional similarities with the CD74HC138 but provides enhanced noise immunity and direct interface capabilities with legacy TTL logic families due to its HCT input threshold characteristics.

Replacement Considerations

• CD74HC138
• SN74HCT138PWR
• MM74HCT138MTCX