SN74HCS251PWR

Overview

The SN74HCS251PWR is an 8-to-1 data selector/multiplexer featuring Schmitt-trigger inputs and strobe-controlled complementary 3-state outputs. It operates within a supply voltage range of 2 V to 6 V and supports an ambient temperature range from -40°C to +125°C. The device provides balanced CMOS outputs capable of ±7.8 mA drive current at 6 V. Propagation delay ranges from 6 ns to 72 ns depending on voltage and temperature, with a maximum switching frequency up to 36 MHz.

Feature Summary

• Schmitt-trigger inputs provide high noise rejection and tolerance for slow or noisy input signals
• Balanced CMOS 3-state outputs allow direct interfacing with bus-organized systems
• Full binary decoding selects one of eight data sources based on address inputs

Applications

• Data selection in digital systems
• Multiplexing multiple data sources onto a single line

Procurement Notes

Verify the specific ordering suffix matches the required package type, as the SN74HCS251 family includes both SOIC and TSSOP variants. Confirm that the component meets the necessary automotive or industrial qualification standards if applicable to the target design environment. Ensure compatibility with existing PCB footprint dimensions before finalizing procurement.

Selection Notes

Select this component when designing circuits requiring robust noise immunity due to its Schmitt-trigger architecture. It is suitable for applications needing low static power consumption alongside moderate output drive capabilities. Consider the extended temperature range for operation in harsh environments where standard commercial grade devices may fail.

Part Context

This part belongs to the Texas Instruments SN74HCS series, which combines HCMOS speed with CMOS low power consumption. The HCS designation indicates the inclusion of Schmitt-trigger inputs, distinguishing it from standard HC logic families. This series is designed for general-purpose digital applications requiring reliable signal integrity.

Replacement Considerations

Direct pin-compatible alternatives include the SN74HC251 for non-Schmitt-trigger applications. For automotive-grade requirements, consider the SN74HCS251QPWRQ1 variant which carries AEC-Q100 qualification.