SN74HC165N 8-Bit Shift Register IC

The SN74HC165N is an 8-bit parallel-in/serial-out (PISO) shift register IC designed to expand the number of digital inputs available to microcontrollers and development boards. It can read 8 parallel input signals and transfer them serially using only a few microcontroller pins.

This IC is useful for Arduino, ESP32, Raspberry Pi, STM32, digital electronics, keypad interfaces, switch monitoring, LED projects, and embedded systems where additional digital inputs are required.

The SN74HC165N 8-bit shift register IC is a high-speed CMOS parallel-in/serial-out shift register that allows multiple digital inputs to be read using a small number of microcontroller pins.

It provides 8 parallel data inputs that can be loaded into the internal register and then shifted out through a serial output. By connecting multiple SN74HC165N ICs together, you can expand the number of digital inputs while using only a few pins from an Arduino, ESP32, Raspberry Pi, STM32, or other microcontroller.

The SN74HC165N is particularly useful when a project has more switches, push buttons, sensors, DIP switches, or digital signals than the available GPIO pins.

For example, one SN74HC165N can monitor 8 digital inputs, while two connected ICs can monitor 16 inputs, three can monitor 24 inputs, and so on.

It is a practical and inexpensive solution for GPIO expansion, digital input expansion, Arduino projects, embedded electronics, robotics, automation, control panels, and DIY electronics projects.

Features:

• 8-bit parallel-in/serial-out shift register
• 8 individual parallel data inputs
• Serial data output
• Supports cascading multiple shift registers
• Reduces microcontroller GPIO requirements
• CMOS technology
• Suitable for digital electronics projects
• Compatible with many microcontroller platforms
• Useful for Arduino and embedded-system projects
• Through-hole DIP package for easy prototyping
• Suitable for breadboards and educational electronics projects

Specifications:

Important: For production designs, verify the exact electrical limits, operating voltage, input/output thresholds, and timing characteristics against the datasheet for the specific SN74HC165N manufacturer/version you are purchasing.

Pin Function Overview

The SN74HC165N uses a 16-pin DIP package.

Important signals include:

• A–H: 8 parallel data inputs
• QH: Serial data output
• CLK: Clock input
• SH/LD: Shift/load control
• CLK INH: Clock inhibit/control
• CE-related control: Used according to the device's control logic
• VCC: Positive supply
• GND: Ground