The MCP23017-E/SS is a 16-bit Input/Output Expander with an I2C interface manufactured by Microchip. It is a digital hardware device that provides 16 GPIO ports with individually configured Input/Output abilities. The device works as a ‘bridge’ between the I2C bus of a microcontroller or system on chip and the application’s I/O requirements. It provides the necessary control to interface with external devices such as an LED, LCD display, ADC, DAC, or a motor. The MCP23017-E/SS simplifies system design, reduces board space, lowers system costs, and makes it easier to interface with other devices. It is suitable for a variety of applications, including data entry systems, handset displays, and interface systems.