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ATxmega128A3U-AU

MCHPATxmega128A3U-AU

Microchip Technology
Same XMEGA-A3U family with integrated USB but 128 KB flash for slightly smaller code size needs.
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Overview

The ATxmega128A3U-AU is an 8/16-bit AVR XMEGA microcontroller featuring an integrated USB interface, 128KB of flash memory, and 8KB of RAM. It operates at speeds up to 32MHz and includes a comprehensive set of peripherals and security features. This MCU is well-suited for embedded applications requiring moderate processing power and USB connectivity.

Why Choose This Part

Engineers benefit from the ATxmega128A3U-AU's integrated USB controller, simplifying connectivity. The XMEGA architecture provides efficient 8/16-bit processing with a rich set of peripherals including a four-channel DMA controller and eight-channel event system. Its advanced power management modes, including 1.3uA standby current, help achieve low power consumption for battery-operated designs.

Applications

USB Peripherals
Ideal for designing USB-connected devices such as human interface devices (HIDs), mass storage devices, or other custom USB accessories, leveraging its integrated full-speed USB interface.
Industrial Control Panels
Its robust peripheral set, including DMA, event system, and various communication interfaces (I2C, SPI, UART), makes it suitable for control and data acquisition in industrial systems.
Data Loggers
With 128KB flash and 8KB RAM, along with integrated EEPROM, the ATxmega128A3U-AU can manage data logging applications, utilizing its low-power modes for extended battery life.
Sensor Interfaces
The presence of analog comparators, external interrupts, and multiple communication protocols allows for efficient interfacing with various analog and digital sensors.
Portable Electronic Devices
Its low-power operation, with sleep currents down to 1.3uA in standby, coupled with a 32MHz clock speed, makes it suitable for battery-powered portable devices where efficiency is key.

Key Specifications

Speed 32MHz
RAM Size 8K x 8
Core Size 8/16-Bit
EEPROM Size 2K x 8
Peripherals Brown-out Detect/Reset, DMA, POR, PWM, WDT
Connectivity I2C, IrDA, SPI, UART/USART, USB
Mounting Type Surface Mount
Number of I/O 50
Core Processor AVR
Package / Case 64-TQFP
Data Converters A/D 16x12b; D/A 2x12b
Oscillator Type Internal
Program Memory Size 128KB (64K x 16)
Program Memory Type FLASH
Operating Temperature -40degC ~ 85degC (TA)
Supplier Device Package 64-TQFP (14x14)
Voltage - Supply (Vcc/Vdd) 1.6V ~ 3.6V

Getting Started

To get started, developers can use Microchip Studio (formerly Atmel Studio) IDE, which provides a comprehensive development environment for AVR microcontrollers. Debugging and programming are typically done via a JTAG or PDI interface, requiring compatible programmers like the Atmel-ICE. The ATxmega128A3U-AU is supported by standard AVR toolchains and libraries.

Also Consider

ATxmega256A3U-AU MCHPMicrochip Technology - This part offers double the flash memory (256KB) while retaining the same XMEGA-A3U family features and integrated USB, suitable for larger codebases.
ATSAMD21G18A-AU MCHPMicrochip Technology - If migrating to a 32-bit ARM Cortex-M0+ architecture is an option, the ATSAMD21G18A-AU offers similar flash (256KB), RAM (32KB), and USB capabilities with a more modern core.
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