{"title":"MCP23008 - i2c 8 input/output port expander","handle":"mcp23008-i2c-8-input-output-port-expander","url":"/products/mcp23008-i2c-8-input-output-port-expander","description":"The MCP23008 is an I2C 8-bit I/O port expander that adds 8 general-purpose pins to your microcontroller using just two I2C lines (shared with other I2C devices). Each pin can be configured as input, output, or input with internal pull-up, and an external interrupt output notifies you when any input changes — no polling required.\n\nOperating from 2.7–5.5 V, the chip works with both 3.3 V and 5 V systems. Each I/O pin can sink or source up to 20 mA, making it suitable for driving LEDs directly. The DIP-18 package plugs straight into a breadboard or perfboard.\n\nKey Features\n\n\n8 Configurable I/O Pins – Input, output, or input with pull-up on each pin\n\nI2C Interface – Uses only 2 bus lines, sharable with other I2C devices\n\n3 Address Pins – Up to 8 devices on a single I2C bus (64 I/O pins total)\n\nInterrupt Output – External pin signals input changes without polling\n\n20 mA Per Pin – Drive LEDs directly from the expander\n\nWide Voltage Range – 2.7–5.5 V operation\n\nDIP-18 Package – Breadboard and perfboard friendly\n\n\nIdeal For\n\nExpanding GPIO on Arduino, Raspberry Pi, or other microcontrollers\nDriving multiple LEDs or reading multiple buttons\nProjects requiring more I/O than the microcontroller provides\n\n\nResources\n\nArduino Library (GitHub)\n","vendor":"Adafruit","product_type":"physical","in_stock":true,"options":[],"variants":[{"id":12865,"title":"Default Title","sku":"AF-593","price":4.52,"on_sale":false,"in_stock":true,"available_quantity":32,"option1":"Default Title"}]}