The ATXMEGA128D3-AU is a high performance, AVR 8-bit microcontroller from Microchip. It offers 128KB Flash memory, 16KB of SRAM and 4KB of EEPROM for programs, data storage, and more. It also has a JTAG interface, along with a wide range of I/O ports, communication protocols, and an internal clock source system. The ATXMEGA128D3-AU supports high-end security, cryptography, power management, and other advanced functions such as USB, RTC, PWMT, and more. These features make it suitable for a wide range of embedded system applications from home automation to medical and industrial control.