PCF8574 Module: 8-Channel I2C Expander for Increasing the Number of I/O Ports

PCF8574 Module - 8-Channel I2C I/O Port Expander for ESP8266, ESP32, Arduino, and Raspberry Pi

The I/O port expander module based on the PCF8574 chip is a proven solution that allows you to expand the number of pins on a microcontroller. Thanks to its wide supply voltage range from 2.5 V to 5 V, the module works seamlessly with popular platforms such as Raspberry Pi, STM32 (3.3 V), and Arduino (5 V). Communication takes place via the widely used I2C bus, making it a versatile tool for electronic projects.

Key Technical Features

• Expander chip: PCF8574
• Number of I/O ports: 8 channels
• Supply voltage: 2.5–5 V
• Communication: I2C bus
• Interrupts from input ports: supported
• Configurable I2C address: 8 options (change the 3 least significant bits of the address)
• Hardware configuration: jumpers for changing the I2C bus address
• Daisy chain: supports connecting up to 8 modules, providing a total of 64 additional inputs/outputs

Benefits

• Pin savings: control of 8 ports using just 2 I2C bus signal lines.
• Power supply versatility: trouble-free operation with both 3.3 V and 5 V logic circuits.
• High scalability: easily increase the number of I/O ports by daisy-chaining additional modules.
• Quick configuration: built-in jumpers allow for instant device address changes.
• Simple integration: the module is easy to use and is ideal for a wide variety of electronic applications.

Example Applications

• Building automation systems: controlling multiple relays from a single microcontroller.
• User interfaces: reading the status of multiple buttons or switches on control panels.
• Lighting control: Controlling LEDs in complex projects.
• Alarm systems: monitoring the status of multiple digital sensors.
• Robotics: support for additional limit sensors and actuator modules.

Kit Contents

• Expander module: PCF8574
• Accessories: jumpers for changing the I2C address