SN74HCT157D

Overview

The SN74HCT157D is a quadruple 2-line to 1-line data selector/multiplexer manufactured by Texas Instruments in a 16-pin SOIC package. It operates within a supply voltage range of 4.5 V to 5.5 V and supports an operating temperature range from -40°C to 85°C. The device features buffered inputs and outputs, with typical propagation delays of 15 ns at 5 V. High-current outputs can drive up to 15 LSTTL loads, providing ±6 mA output drive capability at 5 V.

Feature Summary

• TTL-voltage compatible inputs ensure seamless integration with standard logic families
• High-current outputs capable of driving up to 15 LSTTL loads
• Low power consumption with maximum ICC of 80 µA

Applications

• Data routing between multiple sources to common buses
• Function signal generation circuits
• LSTTL load interfacing applications

Procurement Notes

Verify the specific ordering suffix (e.g., DR vs D) for tape-and-reel versus tube packaging requirements. Confirm RoHS compliance status and lead finish details via the latest TI Package Option Addendum. Ensure the selected variant matches the required production status, as some versions may be obsolete or not recommended for new designs.

Selection Notes

Select this component when TTL-compatible input levels are required alongside CMOS performance. Verify that the 4.5 V to 5.5 V supply voltage range aligns with the system design. Consider the SOIC-16 package dimensions and thermal impedance if high-density mounting or specific heat dissipation constraints apply to the application.

Part Context

This part belongs to the HCT logic family, designed to bridge HC CMOS performance with TTL input compatibility. It functions as a quadruple multiplexer, allowing selection between two data sources for four independent channels. The device includes a separate strobe input for enabling or disabling the outputs.

Replacement Considerations

SN74HC157D: Compatible function but requires 2 V to 6 V supply; verify voltage level compatibility.

FAQ

What is the function of the G input?

The G input acts as a strobe. When G is high, all outputs are forced low regardless of other inputs.

How does the SN74HCT157D differ from the SN74HC157D?

The HCT version has TTL-voltage compatible inputs and operates strictly at 4.5 V to 5.5 V, whereas the HC version accepts standard CMOS levels and operates from 2 V to 6 V.