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ATmega32U4

MCHPATmega32U4

Microchip Technology
A widely used USB-enabled AVR MCU with similar USB capability in an alternate AVR family.
Active4,252 in stock
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Overview

The Microchip ATmega32U4 is an 8-bit AVR microcontroller featuring integrated USB 2.0 full-speed/low-speed device capabilities. It operates at up to 16MHz and includes 32KB of Flash, 2.5KB of SRAM, and 1KB of EEPROM. This MCU provides a complete solution for applications requiring direct USB connectivity.

Why Choose This Part

The ATmega32U4 offers a robust 8-bit AVR core with excellent peripheral integration, including a full-speed USB 2.0 device module. Its non-volatile memories (Flash, EEPROM) and self-programming capabilities simplify firmware updates. The broad community support for AVR microcontrollers and its use in popular development platforms like Arduino make it an accessible choice for many projects.

Applications

USB Human Interface Devices (HIDs)
Ideal for implementing USB keyboards, mice, game controllers, and other input devices due to its integrated USB module and native driver support.
Arduino-compatible Development Boards
Used in various Arduino boards, such as the Arduino Leonardo and Micro, providing USB host/device capabilities for flexible prototyping.
USB-to-Serial Converters
Can be configured as a USB-to-UART bridge, enabling communication between a host PC and other embedded systems.
Data Loggers with USB Connectivity
Suitable for data logging applications where collected data needs to be easily transferred to a computer via a standard USB connection.
Custom USB Peripherals
Its versatile USB 2.0 device module allows for the creation of custom USB-enabled devices that can interface with a PC or other USB hosts.

Key Specifications

Speed 16MHz
RAM Size 2.5K x 8
Core Size 8-Bit
EEPROM Size 1K x 8
Peripherals Brown-out Detect/Reset, POR, PWM, WDT
Connectivity I2C, SPI, UART/USART, USB
Mounting Type Surface Mount
Number of I/O 26
Core Processor AVR
Package / Case 44-VFQFN Exposed Pad
Data Converters A/D 12x10b
Oscillator Type Internal
Program Memory Size 32KB (16K x 16)
Program Memory Type FLASH
Operating Temperature -40degC ~ 85degC (TA)
Supplier Device Package 44-VQFN (7x7)
Voltage - Supply (Vcc/Vdd) 2.7V ~ 5.5V

Getting Started

Engineers can get started with the ATmega32U4 using the Microchip Studio (formerly Atmel Studio) IDE, which supports AVR microcontrollers. The Arduino IDE is also a popular choice for prototyping, especially with boards like the Arduino Leonardo. A JTAG programmer/debugger is recommended for advanced debugging and programming of the Flash and EEPROM memories.

ATMEGA32U4 Family

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

Part Number Package Stock
ATmega32U4 (this part) VFQFN-44 4,252
ATMEGA32U4-AU TQFP-44 5,595
ATMEGA32U4-AUR TQFP-44 1,266

Also Consider

ATSAMD21G18A MCHPMicrochip Technology - This 32-bit ARM Cortex-M0+ microcontroller offers higher performance and more memory, with integrated USB for similar applications.
PIC18F4550 MCHPMicrochip Technology - An 8-bit PIC microcontroller with a full-speed USB 2.0 interface, providing an alternative architecture for USB-enabled designs.
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