SN74ALS157AD

Overview

The SN74ALS157AD is a quad 1-of-2 data selector/multiplexer from the Texas Instruments ALS logic series. It features four independent multiplexers in a single package, providing a common output for each pair of inputs based on a shared select line. The device operates within a supply voltage range of 4.5 V to 5.5 V and exhibits a propagation delay of 14 ns. It is housed in a 16-pin SOIC surface-mount package and supports an operating temperature range from 0°C to +70°C.

Feature Summary

• Integrates four independent 2-to-1 multiplexers with a common select input for synchronized channel switching.
• Delivers high-speed signal routing with a propagation delay of 14 ns suitable for fast digital systems.
• Provides true outputs that reflect the selected input state without inversion.

Applications

• Data routing in digital communication systems
• Address decoding circuits
• Signal selection in microprocessor interfaces

Procurement Notes

Verify the specific suffix 'AD' against the manufacturer's current datasheet to confirm the package type and tape/reel specifications. Ensure the component meets RoHS compliance requirements for your assembly process. Confirm availability status as distribution channels may vary between tube and reel packaging formats.

Selection Notes

Select this component when a compact solution for multiple parallel data paths is required. The ALS series offers a balance of speed and power consumption compared to standard TTL. Verify that the 16-pin SOIC footprint matches the PCB layout constraints and that the 5V logic levels are compatible with the driving and receiving circuitry.

Part Context

This part belongs to the SN74ALS157 family of multiplexers. It serves as a functional equivalent to other industry-standard quad multiplexers but utilizes Advanced Low-power Schottky technology. The 'A' variant typically denotes improved electrical characteristics over earlier versions, while 'D' specifies the plastic small-outline package.

Replacement Considerations

Check for SN74ALS157AN (PDIP) if through-hole mounting is required. Verify compatibility with SN74LS157 variants, noting potential differences in propagation delay and power dissipation. Cross-reference with SN74AS157 for higher speed requirements.