SN74HCS165QDYYRQ1

Shift Registers Overview

The SN74HCS165QDYYRQ1 is an automotive-grade, 8-bit parallel-load shift register from Texas Instruments. It operates within a supply voltage range of 2 V to 6 V and supports an ambient temperature range of -40°C to +125°C. The device features Schmitt-trigger inputs for noise rejection and balanced CMOS push-pull outputs capable of ±7.8 mA drive current at 6 V. Propagation delay ranges from 14 ns to 19 ns depending on voltage and temperature. It is housed in a 16-pin SOT-23-THIN package.

Shift Registers Feature Summary

• AEC-Q100 qualified for automotive applications with specified temperature grades
• Schmitt-trigger inputs provide tolerance for slow or noisy input signals
• Balanced CMOS push-pull outputs support high current sinking and sourcing
• Low power consumption with typical supply current of 100 nA

Shift Registers Applications

• Increasing the number of inputs available to a microcontroller
• Cascading multiple units to expand data input capacity while using a single serial interface
• Parallel-to-serial data conversion for system controllers

Shift Registers Procurement Notes

Verify the specific ordering suffix matches the required package type, as the SN74HCS165-Q1 family includes various packages such as TSSOP, SOIC, WQFN, and SOT-23-THIN. Confirm that the Q1 designation aligns with automotive qualification requirements. Ensure the selected variant meets the thermal and electrical specifications necessary for the intended operating environment.

Shift Registers Selection Notes

Select this component when expanding microcontroller I/O ports via serial interfaces is required. The Schmitt-trigger inputs are suitable for environments with signal noise or slow transition times. Verify that the output drive capability meets load requirements without exceeding absolute maximum ratings. Consider cascading capabilities if more than eight bits of parallel input expansion are needed.

Shift Registers Part Context

This part belongs to the SN74HCS165-Q1 family of automotive 8-bit parallel-load shift registers. The family shares core functional characteristics but differs in packaging options including TSSOP, SOIC, WQFN, and SOT-23-THIN. All variants maintain the same electrical performance profile regarding voltage range, logic levels, and switching speeds defined by the HCS logic series.

Shift Registers FAQ

How does the SH/LD pin control data loading?

When the SH/LD input is held low, the device asynchronously loads data from the parallel inputs (A-H). When held high, the device shifts data serially on the rising edge of the clock.

What is the function of the CLK INH input?

The CLK INH input prevents clock pulses from being detected. Holding it high inhibits shifting, effectively pausing the shift operation regardless of the state of the CLK input.

Are unused inputs required to be terminated?

Yes, unused inputs should be terminated to either VCC or ground to prevent undefined states. While Schmitt-trigger inputs tolerate slow transitions, proper termination ensures stable operation and minimizes dynamic current consumption.