Microchip MCP23S08-E/P 8-Bit SPI I/O Expander DIP18

The Microchip MCP23S08-E/P is an 8-bit I/O expander with a serial interface, providing 8-bit, general purpose, parallel I/O expansion for SPI applications. This versatile device allows a system master to enable each I/O as either an input or output by writing to the I/O configuration bits, with data for each port stored in corresponding input or output registers. The polarity of the input port can be inverted via the polarity inversion register, offering flexible signal conditioning.

Key features include a remote bidirectional I/O port, two hardware address pins that allow up to four devices to share the same chip-select, and a configurable interrupt output pin that can be set as active-high, active-low, or open-drain. The interrupt source is configurable to trigger on change from configured defaults or pin change, and the interrupt capture register saves port values at the time of interrupt, preserving the condition that caused it. An external reset input and a maximum low standby current of 1µA enhance power efficiency.

With a supply voltage range from 1.8V to 5.5V, this expander operates reliably across various systems. It comes in a DIP package with 18 pins and offers 8 I/Os, suitable for a wide temperature range from -40°C to 125°C. Ideal for communications and networking applications, the MCP23S08-E/P simplifies I/O expansion in embedded designs.