Atmel's ARM Cortex-M3 Flash MCU with on-chip High Speed USB Device-and-Transceiver
Atmel has announced the SAM3U, the industry’s first ARM Cortex-M3 Flash microcontroller integrating high speed (480 Mbps) USB Device-and-Transceiver, 4-bit 192 Mbps SDIO/SDCard 2.0, 8-bit 384 Mbps MMC 4.3 Host and 48 Mpbs SPI interfaces on-chip. This connectivity, together with the SAM3U’s 96 MHz/1.25 DMIPS/MHz operating frequency, makes the SAM3U the unique Cortex-M3 device suited to applications with intensive communications requirements, such high speed gateways in industrial, medical, data processing and consumer applications. The introduction of the SAM3U expands Atmel’s 32-Bit MCU portfolio consisting of ARM and AVR32 products.
To fully exploit the SAM3U’s high speed communications peripherals, the device is built around a high data-bandwidth architecture with a 5-layer bus matrix, 23 DMA channels and distributed on-chip memory including up to 52k Bytes of SRAM split in three blocks and up to 256k Bytes of Flash in two banks. The dual bank Flash offers in-application programming (IAP) where one memory bank is written with a new version of the firmware while the processor executes from the other bank. A programmable boot feature enables switching between the two Flash banks at the next MCU reboot.
Additional features include an 8-channel each 10- and 12-bit ADC, the latter with integrated Programmable Gain Amplifier (PGA), differential and single ended input to remove external OpAmps and a one Msps sample rate, 4 UARTs, 5 SPI, 2 I2C, I2S, timers, PWM, 128-bit unique ID, and power and reset management. The External Bus Interface offers the choice between 8- and 16-bit data bus widths for extended memory or connection to external FPGAs and ASSPs. The SAM3U’s supply voltage ranges from 1.62V to 3.6V, a feature not commonly found on Cortex-M3-based MCUs.
Jacko Wilbrink, Atmel’s Marketing Director for ARM-based Microcontrollers, commented, “Atmel was the first to adapt USB Full Speed in its ARM Flash MCUs as a de-facto standard peripheral and we are now driving the deployment of USB High Speed in the embedded space. USB Full Speed at 12 Mbps displaced the UART; USB High Speed at 480 Mbps has the potential to replace parallel wire interconnections, reducing cost, improving reliability and improving EMI characteristics.”
Power optimization – The SAM3U incorporates a sophisticated power management regime that minimizes power consumption under all conditions of use. The device can be put in Backup mode with the core and peripherals powered down, in which power consumption is only 2.5 uA. Wake-up from backup mode can be triggered by multiple sources and is accelerated via a high speed on-chip RC Oscillator reducing the average power consumption critical for battery operated systems.
Code portability between SAM7 and SAM3 MCUs – The Cortex-M3 core has a completely new instruction set architecture, different from previous ARM cores. Migrating legacy ARM7 code to the Cortex-M3 requires a complete re-write of the assembler code. Atmel has taken steps to ensure maximum code portability between its ARM7-, ARM9- and Cortex-M3-based microcontrollers. Its SAM7, SAM9 and Cortex-M3-based SAM3 MCUs have identical hardware abstraction layers and a unified programming model, as well as common peripherals that provide near-recompile-and-go code portability between devices.
Comprehensive support eco-system – Atmel’s SAM3U flash MCU is supported by a rapidly growing number of development tools, real-time operating systems (RTOS), middleware products and technical support services from industry-leading third parties that include IAR, Keil, Micrium, and Segger. Atmel provides a software package with register descriptions and device drivers for all peripherals, along with project examples that ease the use of the microcontroller. The SAM3U Evaluation Kit is available for benchmarking and a quick start in application development.
Availability and Pricing – The AT91SAM3U is available in Flash memory densities of 64k, 128k and 256k Bytes and ships in 100 and 144 pin 0.5mm pitch QFP and 0.8 mm pitch BGA packages. Samples are available now. Production volumes will be available in 4Q09, with prices starting at US$3.50 in quantities of 10k units.