PCF8574 I2C I/O Expansion Board

The PCF8574 I2C I/O Expansion Board is a highly reliable digital expander module that allows you to increase your microcontroller’s input/output capabilities through the efficient I2C communication protocol. With only two wires (SDA & SCL), this board provides 8 additional GPIO pins, making it an excellent solution for complex development projects requiring multiple sensors, keypads, displays, or control interfaces.

This module is widely used in Arduino, Raspberry Pi, and NodeMCU ESP8266/ESP32 projects where GPIO pins are limited. Its plug-and-play I2C architecture supports multiple PCF8574 boards on the same bus by adjusting the onboard address selection pins (A0, A1, A2).

Explore more components here:
🔗 Electronics Components — https://electroway.org/product-category/electronics-components/
🔗 Arduino and Accessories — https://electroway.org/product-category/arduino-and-accessories/
🔗 Tools & Accessories — https://electroway.org/product-category/tools-and-accessories/

⭐ Technical Information

Its I2C address selection makes it possible to connect up to 8 PCF8574 modules in one project.

⭐ Applications

🔌 Microcontroller I/O Expansion

• Increasing GPIO pins on Arduino projects

• Adding multiple digital sensors

• Interfacing relays and drivers

⌨️ Input Devices

• 4×4 matrix keypad scanning

• Button panels

• Control panels for DIY automation

📟 Display Expansion

• LCD1602 / LCD2004 with I2C adapters

• LED display boards

🌐 IoT Projects

• Smart home automation

• Wireless sensor nodes

• Industrial monitoring systems

Compatible categories:
🔗 Arduino Boards — https://electroway.org/product-category/arduino-and-accessories/arduino-boards/
🔗 NodeMCU — https://electroway.org/product-category/iot-and-smart-solutions/iot-modules/nodemcu/
🔗 Raspberry Pi Accessories — https://electroway.org/product-category/electronic-accessories/mounts-and-cases/raspberry-pi-mounts-and-cases/

⭐ Precautions

⚠ Provide stable 3.3V or 5V power supply according to the microcontroller.
⚠ Don’t exceed current load on output pins.
⚠ Keep I2C wires short to avoid noise/hum.
⚠ When using multiple modules, ensure correct address configuration (A0–A2 jumpers).

Need power?
🔗 Power Supply Category — https://electroway.org/product-category/raspberry-pi-and-accessories/accessories-raspberry-pi-and-accessories/power-supplies-accessories-raspberry-pi-and-accessories/

⭐ YouTube Tutorial – PCF8574 with Arduino

📺 Watch Video:https://www.youtube.com/watch?v=TaUZNvrH4Yw

📌 Product Summary

The PCF8574 I/O Expansion Board is the perfect solution for expanding microcontroller GPIO pins using just two I2C lines. With 8 additional digital I/Os, stable performance, and broad compatibility with Arduino and IoT boards, it is essential for advanced automation, keypad interfacing, and sensor-rich projects.