SN74HCT138N

Overview

The SN74HCT138N is a 3-line to 8-line decoder/demultiplexer in a 16-pin PDIP package. It operates at 4.5 V to 5.5 V with typical propagation delays of 17 ns at 5.5 V and 45 ns at 4.5 V. The device features TTL-compatible inputs, low power consumption (80 µA max), and outputs capable of driving up to 10 LSTTL loads. Designed for high-speed memory decoding, it includes three enable inputs to simplify cascading.

Feature Summary

• TTL-voltage compatible inputs ensure seamless integration with standard logic families.
• Three enable inputs facilitate simplified cascading and demultiplexing applications.
• Outputs can drive up to 10 LSTTL loads while maintaining low power consumption.

Applications

• High-performance memory address decoding
• Data routing systems
• Demultiplexing data transmission

Procurement Notes

Verify the specific ordering suffix against the manufacturer's current Package Option Addendum to confirm availability and packaging details. Ensure the selected variant matches the required operating temperature range and RoHS compliance status for your application environment.

Selection Notes

Select this component when TTL voltage compatibility is required alongside CMOS performance. The SN74HCT138N is suitable for designs needing minimal system delay in memory decoding or data routing. Verify that the 4.5 V to 5.5 V supply range aligns with the target system voltage.

Part Context

This part belongs to the SNx4HCT138 family of 3-line to 8-line decoders and demultiplexers. It is designed for high-performance applications requiring short propagation delays. The HCT series combines the low power of CMOS with the speed and input compatibility of TTL logic.

Replacement Considerations

SN74HCT138NE4

FAQ

How many enable inputs does the SN74HCT138N have?

It has three enable inputs: two active-low (G2A, G2B) and one active-high (G1).

What is the maximum output drive capability?

The outputs can drive up to 10 LSTTL loads.