SparkFun Shift-In Breakout - SN74HC165

The SparkFun Shift-In Breakout makes it easy to expand the number of digital inputs on your microcontroller using the SN74HC165N parallel-to-serial shift register. Feed up to 8 parallel input lines and read them as a single serial output, freeing up valuable GPIO pins.

All pins are broken out to standard 0.1" spaced headers for easy breadboard prototyping. The data and power pins are aligned so multiple boards can be daisy-chained together, giving you 16, 24, or more inputs with minimal wiring.

Key Features

• 8-Channel Parallel-to-Serial Conversion – Read up to 8 inputs through a single serial line
• Wide Operating Voltage – 2V to 6V DC supply range
• High Clock Speed – Up to 29 MHz at 6V DC
• Low Power Consumption – 80 μA max supply current
• Chainable Design – Aligned data and power pins for easy daisy-chaining
• Breadboard-Friendly – 0.1" spaced headers for quick prototyping
• Complementary Outputs – Both Q and Q̅ outputs available

Ideal For

• Expanding digital inputs on Arduino, Raspberry Pi, or other microcontrollers
• Reading multiple buttons, switches, or sensors with fewer GPIO pins
• Matrix keypad and control panel interfaces
• Learning about shift registers and serial communication

Package Contents

• 1× SparkFun SN74HC165 Shift-In Breakout Board

Resources

• SN74HC165N Datasheet (PDF)
• Schematic (PDF)
• GitHub – Design Files
• Arduino Example Code