SN74AS257NS

Overview

The SN74AS257NS is a quad 2-to-1 data selector/multiplexer from the Texas Instruments AS logic series. It features four independent channels, each selecting between two inputs based on a common select line. The device provides three-state outputs controlled by an output enable input. It operates within a supply voltage range of 4.5 V to 5.5 V and exhibits a propagation delay of 12 ns. Packaged in a 16-pin PDIP for through-hole mounting, it supports standard TTL input levels and functions across an operating temperature range of 0°C to +70°C.

Feature Summary

• Contains four independent 2-to-1 multiplexing circuits sharing common control lines
• Provides three-state outputs to facilitate bus-oriented system connections
• Utilizes AS logic technology for high-speed signal switching capabilities

Applications

• Data selection and routing in digital systems
• Multiplexing multiple data sources onto shared buses
• Interface circuits requiring high-speed signal switching

Procurement Notes

Verify the specific suffix against official documentation to confirm package type and pinout compatibility. Ensure the ordering part number matches the required industrial specifications. Confirm RoHS compliance status and environmental certifications prior to integration. Cross-reference the manufacturer datasheet for exact mechanical dimensions and thermal characteristics.

Selection Notes

Select this component when high-speed switching performance is required compared to standard LS or ALS logic families. The AS series offers faster propagation delays suitable for demanding timing applications. Verify that the 5V supply voltage aligns with the target system architecture. Consider the through-hole packaging requirement for prototyping or specific board layout constraints.

Part Context

This device belongs to the Texas Instruments SN74AS257 family of quadruple 2-line to 1-line data selectors. The AS designation indicates Advanced Schottky logic, which provides superior speed over previous generations while maintaining compatible power consumption levels. This family is designed for general-purpose digital applications requiring reliable data routing.

Replacement Considerations

Compatible substitutes include the SN74AS257D (SOIC package) and SN74AS257J (ceramic DIP). For lower speed requirements, SN74ALS257 variants may be considered if timing margins allow.