GPIO expanders provide easy I/O expansion using standard serial interfaces. GPIO products are used to increase the I/O on an MCU or provide remote I/O using a serial interface.
This application note discusses the feature set and use of the MCP23X08/17 (8-bit and 16-bit) GPIO Expanders.
The MCP23X08 are 8-bit GPIO Expanders:
- MCP23008: I2C Interface
- MCP23S08: SPI Interface
The MCP23X17 are 16-bit GPIO Expanders:
- MCP23017: I2C Interface
- MCP23S17: SPI Interface
The functions and features of the MCP23X08 and MCP23X17 are basically the same, except where otherwise noted.