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ATMEGA16U4-AU

MCHPATMEGA16U4-AU

Microchip Technology
Similar AVR with integrated USB for smaller flash/peripheral needs.
NRND2,985 in stock
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Overview

The ATMEGA16U4-AU is a low-power, 8-bit AVR RISC-based microcontroller featuring 16KB of self-programmable flash memory and an integrated USB 2.0 full-speed/low-speed device controller. It is designed to simplify the development of USB-enabled peripherals by eliminating the need for external USB-to-serial bridge chips. The device operates at up to 16MHz and includes 1.25KB of RAM and 512 bytes of EEPROM.

Why Choose This Part

The primary advantage is the integrated USB controller which supports both full-speed and low-speed operation without an external crystal in certain configurations. Its 44-pin TQFP package provides 26 I/O lines and a JTAG interface for comprehensive on-chip debugging and boundary-scan testing. The architecture executes most instructions in a single clock cycle, achieving nearly 1 MIPS per MHz.

Applications

USB HID Peripherals
Ideal for creating custom keyboards, mice, and joysticks using the integrated USB device controller.
Legacy Port Emulation
Replacing traditional RS-232 serial interfaces with modern USB-to-UART bridges in industrial equipment.
USB Dongles and Keys
Small form-factor security tokens or license keys that require hardware-level USB connectivity.
MIDI Controllers
Developing bus-powered musical instruments and control surfaces that interface directly with digital audio workstations.

Key Specifications

Speed 16MHz
RAM Size 1.25K x 8
Core Size 8-Bit
EEPROM Size 512 x 8
Peripherals Brown-out Detect/Reset, POR, PWM, Temp Sensor, WDT
Connectivity I2C, SPI, UART/USART, USB
Mounting Type Surface Mount
Number of I/O 26
Core Processor AVR
Package / Case 44-TQFP
Data Converters A/D 12x10b
Oscillator Type Internal
Program Memory Size 16KB (8K x 16)
Program Memory Type FLASH
Operating Temperature -40degC ~ 85degC (TA)
Supplier Device Package 44-TQFP (10x10)
Voltage - Supply (Vcc/Vdd) 2.7V ~ 5.5V

Getting Started

Engineers can develop for this part using Microchip Studio or the open-source avr-gcc toolchain. Because it is part of the same family as the ATmega32U4 used in the Arduino Leonardo, it is highly compatible with existing USB libraries like LUFA (Lightweight USB Framework for AVRs). Hardware debugging is supported via the JTAG interface using tools like the Atmel-ICE.

Also Consider

ATMEGA32U4-AU MCHPMicrochip Technology - Offers double the flash memory (32KB) and more RAM (2.5KB) in the same pin-compatible TQFP-44 package.
ATSAMD21G18A-AUT MCHPMicrochip Technology - A modern 32-bit ARM Cortex-M0+ alternative with higher performance and native USB support for more demanding applications.
CH340G WCH - A dedicated USB-to-UART bridge IC to consider if USB functionality is only needed for basic serial debugging of a standard MCU.
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