PCF8574 I_O Expander

The PCF8574 is an 8-bit input/output (I/O) expander designed for the two-line bidirectional I2C bus. It allows you to add 8 digital I/O pins to your microcontroller using just two I2C pins (SDA and SCL), making it ideal for expanding the I/O capabilities of Arduino, ESP32, and other microcontrollers. The device features eight quasi-bidirectional ports, which can be used as inputs or outputs without external components, and can directly drive LEDs. It operates over a wide supply voltage range of 2.5V to 6V, with a low standby current consumption of just 10µA. The PCF8574 includes three hardware address inputs, allowing up to 8 devices on the same I2C bus, and an open-drain interrupt output for efficient polling. Common applications include LED control, keypad scanning, relay control, and general I/O expansion in embedded systems. Choose this component for its reliability, wide voltage compatibility, and proven performance in countless hobbyist and professional electronics projects.