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ATMEGA16U2-AU

MCHPATMEGA16U2-AU

Microchip Technology
Another USB-enabled AVR commonly used for USB-serial or simple USB bridges
NRND25,258 in stock
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Overview

The ATMEGA16U2-AU is an 8-bit AVR RISC-based microcontroller featuring 16KB of ISP Flash memory and an integrated USB 2.0 full-speed device module. It is most recognized for its role as a high-performance USB-to-serial bridge in the Arduino ecosystem, providing a reliable interface between a host PC and a primary MCU. The device includes a 48 MHz PLL for USB clock recovery, eliminating the need for external crystals in some configurations.

Why Choose This Part

This MCU integrates a hardware USB 2.0 full-speed engine with a dedicated PLL, reducing external component count for communication tasks. Its 32-pin TQFP package provides a compact footprint while offering 22 programmable I/O lines and 512 bytes of EEPROM for non-volatile parameter storage. The architecture supports read-while-write operation and is fully compatible with the extensive LUFA (Lightweight USB Framework for AVRs) library.

Applications

USB-to-UART Bridge
Commonly used as the interface controller on development boards to bridge USB communication to a target MCU serial port.
Custom HID Peripherals
Ideal for creating small-footprint USB keyboards, mice, or game controllers using the integrated USB device module.
Firmware Update Dongles
Utilized in portable programming tools that require a USB interface to deliver firmware payloads to other embedded systems.
USB Condition Monitoring
Acting as a low-power sensor node that reports data directly to a host computer over a standard USB bus.

Key Specifications

Speed 16MHz
RAM Size 512 x 8
Core Size 8-Bit
EEPROM Size 512 x 8
Peripherals Brown-out Detect/Reset, POR, PWM, WDT
Connectivity SPI, UART/USART, USB
Mounting Type Surface Mount
Number of I/O 22
Core Processor AVR
Package / Case 32-TQFP
Oscillator Type Internal
Program Memory Size 16KB (8K x 16)
Program Memory Type FLASH
Operating Temperature -40degC ~ 85degC (TA)
Supplier Device Package 32-TQFP (7x7)
Voltage - Supply (Vcc/Vdd) 2.7V ~ 5.5V

Getting Started

Development is typically performed using Microchip Studio or the AVR-GCC toolchain combined with the LUFA library for USB stack implementation. Hardware debugging is supported via the on-chip debugWIRE system, while initial programming can be done through the SPI interface using an AVRISP mkII or similar programmer. For rapid prototyping, many engineers reference the Arduino Uno Rev3 or Mega2560 schematics where this part is the standard USB interface.

ATMEGA16U2 Family

Comparing specs that differ across variants. The current part is highlighted.

Part Number Package Stock
ATMEGA16U2-AU (this part) TQFP-32 25,258
ATMEGA16U2-MU VFQFN-32 16,439

Also Consider

ATmega32U4 MCHPMicrochip Technology - Provides double the Flash memory and additional analog inputs for more complex standalone USB applications.
CP2102N SiLSilicon Labs - A dedicated USB-to-UART bridge that requires no firmware development if only serial communication is needed.
CH340G WCH - A cost-optimized dedicated USB-to-serial converter widely used in budget-sensitive consumer electronics.
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