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ATxmega256A3U-AU

MCHPATxmega256A3U-AU

Microchip Technology
XMEGA-class AVR with integrated USB and larger peripheral set for higher-performance 8/16-bit AVR applications.
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Overview

The ATxmega256A3U-AU is a high-performance, low-power 8/16-bit microcontroller from the AVR XMEGA family. It features 256KB of in-system programmable flash, 16KB of RAM, and an integrated USB controller, making it suitable for applications requiring moderate processing power and USB connectivity. Its advanced peripheral set includes a four-channel DMA controller and an eight-channel event system for efficient data handling and inter-peripheral communication.

Why Choose This Part

Engineers benefit from the ATxmega256A3U-AU's high-performance 32MHz AVR core, which provides efficient execution for demanding tasks. The integrated USB peripheral simplifies connectivity to PCs or other USB hosts, reducing external component count. Its extensive set of peripherals, including a DMA controller and event system, allows for complex system designs with minimal CPU intervention, while power-saving modes help extend battery life in portable applications.

Applications

USB Human Interface Devices (HIDs)
Ideal for creating USB keyboards, mice, game controllers, and other HIDs due to its integrated USB controller and interrupt capabilities.
Capacitive Touch Applications
Supports QTouch library, enabling the development of user interfaces with capacitive touch buttons, sliders, and wheels without external touch controllers.
Industrial Control Systems
Its robust peripheral set, including DMA, event system, and various communication interfaces (I2C, SPI, UART), makes it suitable for managing sensors and actuators in industrial environments.
Data Logging Devices
The 256KB flash memory and 16KB RAM, combined with USB connectivity, allow for efficient storage and transfer of collected sensor data or system logs.
Embedded Communication Hubs
Can act as a central processing unit for bridging different communication protocols (e.g., I2C to USB, SPI to USB) in embedded systems.

Key Specifications

Speed 32MHz
RAM Size 16K x 8
Core Size 8/16-Bit
EEPROM Size 4K 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 256KB (128K 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 with the ATxmega256A3U-AU, engineers can use Microchip's MPLAB X IDE and the MPLAB XC8 compiler for 8-bit AVR microcontrollers. Evaluation kits like the ATxmega256A3U Xplained evaluation kit (if available) offer a quick way to begin development. Standard AVR programming tools, such as the Atmel-ICE, can be used for flashing and debugging the device.

Also Consider

ATSAMD21G18A-AU MCHPMicrochip Technology - For a 32-bit ARM Cortex-M0+ alternative with integrated USB and similar memory footprint, offering higher performance and a different architecture.
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