Tag Archives: Custom Logic module (XCL)

Atmel’s AVR XMEGA MCU: High integration and ultra-low power

Earlier this week, Bits & Pieces took a close look at Atmel’s AVR UC3 which is built around high-performance 32-bit AVR architecture and optimized for highly integrated applications. Today, we are getting up close and personal with Atmel’s AVR XMEGA, an MCU designed for real-time performance, high integration and ultra-low power.

Powered by an Atmel AVR CPU, the AVR XMEGA is tuned to minimize code size and maximize execution speed. Indeed, its true single-cycle execution of arithmetic and logic operations allows AVR XMEGA microcontrollers to perform close to 1 MIPS per MHz. The fast-access register file with 32 x 8-bit general-purpose working registers is directly connected to the arithmetic logic unit (ALU). During a single clock cycle, the ALU can be fed two arbitrary registers, do a requested operation and write back the result. It provides efficient support for 8-, 16-, and 32-bit arithmetic. Plus, 12-bit analog-to-digital converters (ADCs) with gain stage offer a combined throughput of 4MSPS, while fast 12-bit digital-to-analog converters (DACs) with high drive strength, as well as other functions, reduce the need for external components.

As noted above, the AVR XMEGA boasts real-time performance, with an Event System that facilitates inter-peripheral signaling with 100% predictable response time. To help offload the CPU, all peripherals can use direct memory access (DMA) for data transfer. Meanwhile, Atmel’s stalwart picoPower technology enables true 1.6V operation, down to 100nA RTC operation with full SRAM retention for fastest possible wake-up time.

“In terms of integration, AVR XMEGA devices include Advanced Encryption Standard (AES) and Data Encryption Standard (DES) crypto modules, up to 32 pulse-width modulation (PWM) outputs, 8 UARTs, 4 TWI (I2C) and 4 serial peripheral interface (SPI) channels, a cyclic redundancy check (CRC) generator module and more,” an Atmel engineering rep told Bits & Pieces.

“On the USB connectivity side, the AVR XMEGA delivers full-speed operation without the need for external crystals, 31 endpoints, along with a special multi-packet function that maximizes data transfer rates while minimizing CPU load.”

AVR XMEGA devices also feature an innovative XMEGA  consisting of two independent 8-bit timers/counters and two lookup tables used for defining glue logic. It is designed to reduce bill of material (BOM) and PCB size as the XCL can replace external circuitry such as delay elements, RS-latches, D-latches, D-flip-flops chip-select logic, AND, NAND, OR, NOR, XOR, XNOR, NOT, MUX AND/OR/XOR logic gates. In addition, it can, in conjunction with the USART, enable customized communication protocols.

And last, but certainly not least, Atmel’s AVR Software Library include a plethora of device drivers and communication stacks that save time and development effort, allowing engineers to focus on more important design tasks. Similarly, Atmel’s QTouch Sensing Library helps devs to easily integrate robust capacitive touch sensing interfaces for buttons, sliders and wheels.

Interested in learning more? Additional Atmel AVR XMEGA technical details are available here.