The MCP23S17-E/SS is a 16-bit I/O expander from Microchip Technology, designed to extend the input/output capabilities of microcontrollers via an SPI interface. Housed in a compact SSOP-28 package, this device provides two 8-bit ports (PORTA and PORTB) configurable as inputs or outputs, enabling flexible control and signal acquisition. It operates over a wide supply voltage range of 1.8V to 5.5V and supports SPI communication speeds up to 10 MHz, making it suitable for high-speed data transfer in embedded systems.

Key Features

This expander features programmable input/output direction per pin, internal pull-up resistors, and interrupt capabilities for event-driven signaling. Its SPI interface eliminates the need for external clock stretching, ensuring seamless integration with microcontrollers. The MCP23S17-E/SS includes 256 bytes of non-volatile memory for configuration retention during power loss and supports interrupt-on-change functionality for real-time monitoring of input pins. Additionally, it offers low power consumption in sleep mode and operates across a temperature range of -40°C to +85°C, ensuring reliability in industrial and consumer environments.

Applications

Ideal for industrial automation, smart home systems, and sensor networks, the MCP23S17-E/SS is widely used in applications requiring scalable I/O expansion, such as robotics, data acquisition, and IoT devices. Its SPI interface and interrupt capabilities make it suitable for real-time control systems, while its compact size and low power consumption enhance its utility in battery-operated or space-constrained designs. It is also employed in automotive infotainment systems and medical devices for managing multiple sensors and actuators.

Summary

The MCP23S17-E/SS delivers robust I/O expansion with SPI-based high-speed communication and programmable flexibility, making it a versatile solution for embedded systems demanding enhanced connectivity and control. Its combination of non-volatile configuration storage, interrupt-driven operation, and broad voltage compatibility simplifies design complexity while ensuring reliable performance in diverse applications. This device is a critical component for engineers seeking to expand microcontroller functionality efficiently in both industrial and consumer electronics.