Overview

The PCF8575 is a 16-bit I/O expander that provides general-purpose remote I/O expansion via the I2C bus. It’s the 16-bit version of the popular PCF8574 (8-bit).

The module features:

• 16 quasi-bidirectional I/O ports
• I2C interface (up to 400kHz)
• Low standby current consumption
• Open-drain interrupt output
• Addresses: 0x20-0x27 (configurable via A0, A1, A2 pins)
• Operating voltage: 2.5V-5.5V
• 5V tolerant I/Os
• Latched outputs with high current drive
• Active LOW interrupt pin

Configuration Notes

• Requires I2C interface
• Platform: pcf8574 (ESPHome uses same platform for PCF8575)
• Default I2C addresses: 0x20-0x27 (configurable via address pins, 0x20 by default)
• Use pcf8575: true configuration option
• Each pin can be configured as input or output
• Pins can be used with binary_sensor, switch, and other GPIO-based components
• Provides 16 additional GPIO pins over I2C