Pimoroni IO Expander Breakout

Add oodles of extra analog-friendly input and output pins to your Raspberry Pi (or Raspberry Pi Pico) project!

This breakout uses a clever Nuvoton MS51 microcontroller and some I2C magic to give you a whopping 14 additional input/output pins to connect things up to. Eight of the pins are hooked up to an Analog to Digital Converter so you can easily use old skool analog sensors with your Raspberry Pi, as well as passive components that use an analog signal (like light dependent resistors).

Six of the pins can be used as (up to 16-bit) PWM outputs, great for controlling devices that require a simulated analog output like servos or non-addressable LEDs. You can attach it to your Pi's GPIO directly or via a breadboard with the included headers, but it's also compatible with our fancy solderless Breakout Garden, which makes it super easy to use several different breakouts at the same time. Why not couple it with one of our teeny display breakouts to show the results from all those lovely sensors?

Breakouts made after August 2023 feature the long side of the pin headers pointing out of the back of the breakout instead of the front, allowing one-sided assembly. Pinout is compatible with all Raspberry Pi models and supports Raspberry Pi Pico with C++/MicroPython libraries. The kit includes an IO Expander Breakout, straight male and right angle female headers.

We've designed this breakout board so that you can solder on the right angle female header and pop it straight onto the bottom left 5 pins on your Raspberry Pi's GPIO header. Software support includes Python, C++, and an Arduino library, allowing extensive compatibility and customization.

The default I2C address is 0x18, customizable in software for multiple IO Expanders or avoiding conflicts with other devices. The board employs a Nuvoton MCU with custom firmware, but adventurous users can substitute their own for specialized applications. Dimensions: 26x24.5x12mm (LxWxH).