SN74LVC165APWR

Shift Registers Overview

The SN74LVC165APWR is an 8-bit parallel-load shift register from the LVC logic family, manufactured by Texas Instruments. It operates within a supply voltage range of 1.1V to 3.6V and features over-voltage tolerant inputs supporting up to 5.5V independent of VCC. The device provides high push-pull output drive strength and supports partial-power-down with back-drive protection (Ioff). It includes a serial input for daisy-chaining capabilities and offers both standard and inverted serial outputs.

Shift Registers Feature Summary

• Asynchronous parallel data loading via dedicated SH/LD select pin
• Over-voltage tolerant inputs allowing operation with signals exceeding VCC
• Supports partial-power-down mode with back-drive protection circuitry
• High push-pull output drive capability across low voltage ranges

Shift Registers Applications

• Increasing the number of inputs available on a microcontroller
• Reading in board revision information
• Cascading multiple units to expand system data input capacity

Shift Registers Procurement Notes

Verify that the ordering suffix matches the required package type, as the base part number covers multiple physical packages. Confirm the specific temperature grade and electrical characteristics align with the design requirements before procurement. Ensure the component meets all relevant RoHS standards and functional safety ratings if applicable to the target application environment.

Shift Registers Selection Notes

Select this component when a low-voltage parallel-to-serial conversion is required with minimal pin count usage. Consider the LVC series for compatibility with modern low-voltage logic families. Evaluate the propagation delay specifications against the system clock frequency to ensure timing margins are met during the shifting process.

Shift Registers Part Context

This component belongs to the SN74LVC165A family of 8-bit parallel-load shift registers. The 'PWR' suffix specifically denotes the TSSOP-16 surface-mount package variant. This family is designed for applications requiring efficient data serialization from parallel sources while maintaining low power consumption and robust performance across varying supply voltages.

Shift Registers Replacement Considerations

SN74LVC165ADWR

Shift Registers FAQ

How does the device handle partial power-down?

The device includes circuitry to disable all outputs when the supply pin is held at 0V. In this state, outputs neither source nor sink current regardless of applied input voltages, preventing back-driving.

What is the function of the CLK INH pin?

The CLK INH pin acts as a clock inhibit input. Clocking is inhibited when this pin is high. It can be used interchangeably with the CLK pin for triggering shifts, provided the transition levels are managed correctly relative to the other clock signal.