SN74LS257BNS

Overview

The SN74LS257BN is a quad 2-to-1 data selector/multiplexer manufactured by Texas Instruments. It belongs to the LS (Low-power Schottky) logic series and features four independent multiplexing circuits. Each circuit selects one of two inputs based on a common select line, providing true outputs with three-state capability. The device operates within a supply voltage range of 4.75 V to 5.25 V and supports through-hole mounting in a 16-pin PDIP package.

Feature Summary

• Contains four independent 2-to-1 multiplexers with common select lines
• Features three-state outputs for bus-oriented systems
• Utilizes Low-power Schottky (LS) TTL technology

Applications

• Bus-oriented systems requiring signal selection
• Data routing applications
• General-purpose digital logic circuits

Procurement Notes

Verify the specific manufacturer origin, as the SN74LS257BN designation has been produced by multiple vendors including Motorola/NXP and Texas Instruments. Confirm that the component matches the required LS logic family specifications and PDIP-16 package dimensions. Ensure the datasheet corresponds to the exact part number variant to avoid functional discrepancies related to output drive strength or pinout differences between manufacturers.

Selection Notes

Select this component when low power consumption is required alongside moderate switching speeds typical of LS logic. It serves as a direct replacement for other quad 2-to-1 multiplexers in the 74LS family. Consider the three-state output feature if the design requires driving shared data buses without external tri-state buffers.

Part Context

This component is part of the standard 74LS257 family of quadruple 2-input multiplexers. It provides a cost-effective solution for selecting between two data sources for four separate channels. The LS series offers a balance between power dissipation and speed, making it suitable for general-purpose digital applications where high-speed performance is not critical.

Replacement Considerations

SN74LS257BN (Texas Instruments)

FAQ

What is the function of the enable input?

The enable input controls the three-state outputs. When active, the selected data is passed to the output; when inactive, the outputs enter a high-impedance state.

Does the SN74LS257BN provide inverted outputs?

No, the SN74LS257BN provides true (non-inverted) outputs.