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MCP2221A-I/ML

MCHPMCP2221A-I/ML

Microchip Technology
Compact USB-to-UART/I2C bridge popular for low-cost USB-to-I2C conversions and easy-to-use Microchip drivers and libraries.
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Overview

The MCP2221A-I/ML is a USB-to-UART/I2C protocol converter that enables easy communication between a host computer and peripherals. It features integrated USB termination resistors and a self-powered or bus-powered design, operating at voltages from 3V to 5.5V. This 16-QFN package variant is ideal for space-constrained designs needing bridge functionality without complex firmware development.

Why Choose This Part

The device is recognized as a USB HID-class device, eliminating the need for custom drivers on most operating systems. It offers versatile GPIO pins that can be configured for functions like clock output or ADC inputs, providing more utility than a standard serial bridge.

Applications

USB-to-I2C Bridging
Connecting PC-based configuration tools to sensors, EEPROMs, or motor controllers during production or calibration.
Embedded System Debugging
Providing a dedicated UART serial port for logging and console access over a standard USB connection.
Custom PC Peripherals
Building low-cost HID-class devices like custom input controllers or data acquisition modules.
In-Circuit Programming
Acting as a bridge for firmware updates to microcontrollers that support I2C or UART bootloading.

Key Specifications

Function Bridge, USB to I2C/UART
Protocol USB
Interface I2C, UART
Standards USB 2.0
Package / Case 16-VQFN Exposed Pad
Current - Supply 13mA
Voltage - Supply 3V ~ 5.5V
Operating Temperature -40degC ~ 85degC
Supplier Device Package 16-QFN (4x4)

Getting Started

Start development using the ADM00559 evaluation board or the MCP2221 Utility software for quick configuration of internal descriptors. Microchip provides a comprehensive C# and C++ library for developing host-side applications that interface with the I2C and UART engines.

MCP2221 Family

Part NumberDifferenceStock
MCP2221A-I/ST ST 9,204
MCP2221AT-I/ML T-I/ML 1,608
MCP2221A-I/P P 214
MCP2221A-I/SN SN —
Also available as: MCP2221A, MCP2221

Also Consider

FT232RL FTDI - The industry standard for USB-to-UART bridging, though it lacks the integrated I2C support found in the MCP2221A.
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