Adafruit MCP23017 I2C GPIO Expander Breakout
Pimoroni
£4.75
This Adafruit MCP23017 I2C GPIO Expander Breakout has 16 GPIO with matching ground pad. We particularly like the '17 as an expander for it's simple no-nonsense capability. It runs happily from 3V or 5V logic and power. Each GPIO can be an output driving up to 25mA, so LEDs are no problem. Or, each can be an input, with optional pullup. There are two IRQ pins that are configurable for what inputs to keep track of so no I2C bus polling is required. With 3 address pins, you can have up to 8 on a single bus for a total of 8 x 16 = 128 GPIO all on one I2C bus! Adafruit have got solid Arduino and Ci
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Buy from PimoroniPrice seen 2026-09-05. Affiliate link.
