MCHPMCP2221AT-I/ML
Overview
The MCP2221AT-I/ML is Microchip's USB 2.0 to I2C bridge IC that lets a host PC or other USB host access I2C devices and control general-purpose I/O through a single-chip USB peripheral. It integrates the USB protocol handling and a bridge to I2C and GPIO so you do not need a separate microcontroller for host-level I2C access. The device is commonly used to add USB connectivity for sensor, EEPROM, and peripheral control in test and prototype setups.
Why Choose This Part
The MCP2221A family reduces BOM and development time by combining the USB interface and I2C master functionality in one part, eliminating the need to implement USB on a separate microcontroller. Its integrated GPIOs and simple host-side command model make it convenient for test, prototype, and PC-controlled peripheral tasks. Being a dedicated bridge IC also simplifies compliance and USB endpoint management compared with implementing custom firmware on an MCU.
Applications
Getting Started
Begin with Microchip's datasheet and application notes for MCP2221A to understand pinout, electrical requirements, and command protocol. For evaluation, use available breakout modules or purchase the part on a small PCB; Microchip publishes example host-side code and documentation for Windows and Linux to issue I2C transactions and control GPIOs. Ensure you have a USB host (PC) and a short I2C bus for initial tests, and observe I2C pull-up and power recommendations from the datasheet.
MCP2221 Family
Comparing specs that differ across variants. The current part is highlighted.
| Part Number | Package | Stock |
|---|---|---|
| MCP2221AT-I/ML (this part) | — | 1,608 |
| MCP2221A-I/ML | VQFN-16 | 1,666 |
| MCP2221A (Microchip) | SOIC-14 | 9,526 |
| MCP2221A-I/P | DIP-14 | 214 |
