PIM517 IO Expander Breakout Board Pimoroni PIM517 IO Expander Breakout Board is designed with a good number of extra analog-friendly input and output pins to Raspberry Pi. This breakout board supports the Nuvoton MS51 microcontroller and some I2C interface that gives a whopping 14 additional I/O pins to connect things up to. The eight of the pins are hooked up to an ADC and six of the pins can be used as (up to 16-bit) PWM outputs. This IO expander breakout board can attach to Pi's GPIO directly or via a breadboard that includes headers. This board is also compatible with fancy solderless Breakout Garden that makes it super easy to use several different breakouts at the same time.