MCP23009-E/MG

Overview

The MCP23009-E/MG is an 8-bit I/O expander featuring an I2C interface, housed in a 16-lead QFN package (3x3x0.9 mm). It operates within a voltage range of 1.8V to 5.5V and supports clock frequencies up to 3.4 MHz. The device provides eight bidirectional GPIO pins with open-drain outputs capable of 25 mA sink current per pin and 200 mA total. Key features include configurable interrupt-on-change, polarity inversion registers, internal pull-up resistors, and a hardware address pin allowing up to eight devices on the bus.

Feature Summary

• Provides 8-bit remote bidirectional I/O expansion via I2C serial interface
• Features configurable interrupt output with interrupt-on-change capability
• Includes hardware address pin for multi-device bus addressing
• Supports input polarity inversion and internal pull-up resistor configuration

Applications

• General purpose parallel I/O expansion for microcontroller systems
• Multi-device I2C bus configurations requiring hardware address selection
• Systems requiring interrupt-driven input state monitoring

Procurement Notes

Verify the specific ordering suffix against the manufacturer's official documentation to confirm package type and temperature grade. Ensure the procurement channel sources components directly from authorized distributors or the manufacturer to guarantee authenticity and traceability. Cross-reference the full part number with the latest datasheet revision to confirm compatibility with system requirements.

Selection Notes

Select this component when an I2C interface is required rather than SPI. The QFN package is suitable for space-constrained surface-mount designs. Consider the single hardware address pin limitation if more than eight devices are needed on the same bus segment. Verify that the open-drain output characteristics align with the load requirements of the connected peripherals.

Part Context

This part belongs to the MCP23X09 family, which includes both I2C (MCP23009) and SPI (MCP23S09) variants. The primary distinction between these variants is the serial communication protocol. The E/MG suffix indicates the specific commercial temperature grade and QFN packaging configuration offered by Microchip Technology.

Replacement Considerations

The MCP23S09 serves as the functional equivalent with an SPI interface instead of I2C. Other Microchip I/O expanders like the MCP23017 offer additional ports but differ in register architecture and pin count. Direct substitution requires verifying interface compatibility and pinout alignment.