SN74HCS251QPWRQ1

Overview

The SN74HCS251QPWRQ1 is an automotive-grade 8-to-1 multiplexer featuring Schmitt-trigger inputs and 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 propagation delays as low as 6 ns at 6 V and maximum switching frequencies up to 36 MHz. It includes balanced CMOS outputs capable of sourcing and sinking ±7.8 mA, with typical quiescent current consumption of 100 nA.

Feature Summary

• Schmitt-trigger inputs provide high noise immunity and tolerance for slow or noisy input signals
• Complementary 3-state outputs enable direct interfacing with bus-organized systems
• Full binary decoding selects one of eight data sources based on address inputs
• Strobe-controlled output enable allows precise management of bus traffic

Applications

• Data selection in automotive electronic control units
• Multiplexing sensor signals for processing
• Bus-oriented system routing

Procurement Notes

Verify the component matches the specific automotive qualification requirements by confirming AEC-Q100 Grade 1 certification. Ensure the operating environment stays within the specified -40°C to +125°C temperature range. Check that the supply voltage remains between 2 V and 6 V to maintain electrical characteristics. Confirm the TSSOP-16 package dimensions align with the PCB layout constraints.

Selection Notes

Select this component when designing systems requiring robust signal selection under noisy conditions. The Schmitt-trigger architecture is suitable for applications with slow transition times. Verify that the required output drive current does not exceed the ±7.8 mA limit. Consider the 3-state capability if multiple devices share a common data bus structure.

Part Context

This part belongs to the Texas Instruments SN74HCS251-Q1 family of logic ICs. It is specifically designed for automotive applications, meeting strict reliability standards. The HCS series combines HCMOS speed with CMOS low power consumption. The 'Q1' suffix indicates automotive qualification, while 'PWR' denotes the TSSOP-16 package type.

Replacement Considerations

SN74HCS251PW-Q1

FAQ

How do Schmitt-trigger inputs benefit this multiplexer?

They provide hysteresis, making the device tolerant to slow or noisy input signals without causing excessive dynamic current consumption.

What is the function of the OE pin?

The Output Enable (OE) pin controls the 3-state outputs. When OE is high, the outputs enter a high-impedance state; when low, they are enabled.