SN74HCT138DG4

Overview

The SN74HCT138DG4 is a 3-line to 8-line decoder and demultiplexer manufactured by Texas Instruments. It operates within a supply voltage range of 4.5 V to 5.5 V and features TTL-compatible inputs with low input current. The device incorporates three enable inputs to simplify cascading and data reception. It is designed for high-performance memory decoding and data routing applications requiring short propagation delays, typically 17 ns at 5 V. The component is housed in a 16-pin SOIC package.

Feature Summary

• Designed for high-speed memory decoders and data transmission systems
• Incorporates three enable inputs to simplify cascading and data reception
• TTL-voltage compatible inputs with low power consumption

Applications

• High-performance memory decoding
• Data routing applications
• Data transmission systems

Procurement Notes

Verify the specific ordering suffix 'G4' against the manufacturer's current product folder to confirm RoHS compliance status and lead finish specifications. Ensure the selected package variant matches the required thermal resistance and moisture sensitivity level ratings for the intended assembly process. Cross-reference the active production status with the latest orderable addendum to avoid obsolete part numbers.

Selection Notes

Select this component when system design requires minimal effective delay relative to high-speed memory access times. The HCT logic family ensures compatibility with standard TTL voltage levels while offering lower power consumption compared to older technologies. Verify that the operating temperature range meets the environmental requirements of the target application.

Part Context

This device belongs to the SNx4HCT138 family of 3-line to 8-line decoders and demultiplexers. The family includes variants such as SN74HCT138DR and SN74HCT138PWR, available in different packages like SOIC, TSSOP, and PDIP. The SN74HCT138DG4 specifically denotes the SOIC package version with Green (RoHS compliant) manufacturing attributes.

Replacement Considerations

SN74HCT138DR

FAQ

How many enable inputs does the SN74HCT138DG4 have?

The device incorporates three enable inputs: two active-low (G2A and G2B) and one active-high (G1).

What is the typical propagation delay time at 5 V?

The typical propagation delay time (tpd) is 17 ns when operating at a supply voltage of 5 V.