SN74HCT257DT

Overview

The SN74HCT257DT is a quadruple 2-line to 1-line data selector/multiplexer with 3-state outputs manufactured by Texas Instruments. It operates within a supply voltage range of 4.5 V to 5.5 V and features typical propagation delays of 17 ns at 5.5 V. The device provides high-current 3-state outputs capable of driving system buses directly, with an output drive of ±6 mA at 5 V. It consumes a maximum supply current of 80 µA and accepts TTL-voltage compatible inputs.

Feature Summary

• Provides four independent channels for multiplexing signals from 4-bit data sources to bus-organized systems.
• Features buffered inputs and outputs that interface directly with system buses without loading data lines when disabled.
• Includes 3-state outputs controlled by an active-low strobe input to prevent bus contention.

Applications

• Bus interface applications connecting multiple signal sources in high-performance systems.
• Multiplexing signals from 4-bit data sources to 4-output data lines.
• Data selection circuits requiring direct interfacing with system buses.

Procurement Notes

Verify the specific ordering suffix 'DT' against the manufacturer's official package information to confirm the SOIC-16 surface-mount configuration. Ensure compatibility with the required operating temperature range of -40°C to +85°C for industrial applications. Confirm RoHS compliance status and lead finish specifications via the latest orderable part number documentation before finalizing procurement.

Selection Notes

Select this component when designing bus-organized systems requiring quadruple 2-to-1 data selection with high-speed performance. The HCT logic series ensures TTL voltage compatibility for seamless integration with legacy digital interfaces. Consider the 3-state output capability for managing shared data lines effectively. Verify that the 4.5 V to 5.5 V operating voltage aligns with the target system power supply constraints.

Part Context

This device belongs to the SN74HCT257 family of logic integrated circuits produced by Texas Instruments. It is categorized as a data selector/multiplexer designed for general-purpose digital logic applications. The product line supports various packaging options including SOIC, PDIP, and CDIP to accommodate different mounting requirements and thermal management needs across diverse electronic designs.

Replacement Considerations

Compatible substitutes include SN74HCT257N (PDIP) and SN74HCT257DR (SOIC). Verify pinout compatibility and electrical characteristics match the original design requirements before substitution.