SN74HC257N

Overview

The SN74HC257N is a high-speed CMOS logic device containing four independent 2-line to 1-line data selectors or multiplexers with non-inverting three-state outputs. It operates within a supply voltage range of 2 V to 6 V and supports an operating temperature range from -40°C to +85°C. The device features low power consumption with a maximum ICC of 80 µA and provides ±6 mA output drive at 5 V. Typical propagation delay is 9 ns at 5 V, while transition times are typically 10 ns. It utilizes a 16-pin PDIP package.

Feature Summary

• Contains four independent channels for selecting between two data sources using shared address inputs.
• Outputs enter a high-impedance state when the active-low strobe input is high, preventing bus loading.
• Provides non-inverting outputs suitable for direct interfacing with standard logic families.

Applications

• Bus interface systems requiring signal selection from multiple sources
• Data routing in high-performance digital systems
• Multiplexing operations in microprocessor-based designs

Procurement Notes

Verify the specific ordering suffix 'N' corresponds to the 16-pin Plastic Dual In-Line Package (PDIP) configuration. Confirm RoHS compliance status and lead finish details via the manufacturer's current orderable addendum, as packaging materials may vary by production lot.

Selection Notes

Select this component for applications requiring quad 2-to-1 multiplexing with three-state control. Ensure the design accommodates the 2 V to 6 V supply range and that unused inputs are tied to defined logic levels to prevent floating states. Consider thermal resistance characteristics if operating near maximum temperature limits.

Part Context

This part belongs to the Texas Instruments SNx4HC257 family of quadruple 2-line to 1-line data selectors. It is functionally compatible with other manufacturers' 74HC257 devices but maintains specific electrical parameters defined by TI standards. The 'N' suffix specifically denotes the through-hole PDIP package variant.

Replacement Considerations

SN74HC257D (SOIC package), SN74HC257PW (TSSOP package). Verify pinout compatibility and package dimensions before substitution.