原标题：Atmel ATSAM4LC2A低功耗32位ARM Cortex-M4 MCU开发方案

　　Atmel公司的ATSAM4LC2A是低功耗基于ARM Cortex-M4 RISC 处理器的32位闪存MCU,工作频率高达48MHz.采用最新的picoPower技术,具有超低功耗,工作电流消耗低至90μA/MHz, Thumb®-2指令集, 能够提供高效的信号处理,易用性和高速通信外设，是工业、医疗和消费品应用领域各种功耗敏感设计的理想之选。本文介绍了ATSAM4LC2A主要特性,框图,以及评估板ATSAM4L-EK主要特性,框图,电路图,材料清单和PCB元件布局图.

　　Atmel’s SAM4L series is a member of a family of Flash microcontrollers based on the high performance 32-bit ARM Cortex-M4 RISC processor running at frequencies up to 48MHz.

　　The SAM4L series embeds state-of-the-art picoPower technology for ultra-low power consumption. Combined power control techniques are used to bring active current consumption down to 90μA/MHz. The device allows a wide range of options between functionality and power consumption, giving the user the ability to reach the lowest possible power consumption with the feature set required for the application. The WAIT and RETENTION modes provide full logic and RAM retention, associated with fast wake-up capability (<1.5μs) and a very low consumption of, respectively, 3 μA and 1.5 μA. In addition, WAIT mode supports SleepWalking features. In BACKUP mode, CPU, peripherals and RAM are powered off and, while consuming less than 0.9μA with external interrupt wakeup supported.

　　The SAM4L series offers a wide range of peripherals such as segment LCD controller, embedded hardware capacitive touch (QTouch), USB device & embedded host, 128-bit AES and audio interfaces in addition to high speed serial peripherals such as USART, SPI and I2C. Additionally the Peripheral Event System and SleepWalking allows the peripherals to communicate directly with each other and make intelligent decisions and decide to wake-up the system on a qualified events on a peripheral level; such as I2C address match or and ADC threshold.

　　ATSAM4LC2A主要特性:

　　• Core

　　– ARM® CortexTM-M4 running at up to 48MHz

　　– Memory Protection Unit (MPU)

　　– Thumb®-2 instruction set

　　• picoPower® Technology for Ultra-low Power Consumption

　　– Active mode downto 90μA/MHz with configurable voltage scaling

　　– High performance and efficiency: 28 coremark/mA

　　– Wait mode downto 3μA with fast wake-up time (<1.5μs) supporting SleepWalking

　　– Full RAM and Logic Retention mode downto 1.5μA with fast wake-up time (<1.5μs)

　　– Ultra low power Backup mode with/without RTC downto 1,5/0.9μA

　　• Memories

　　– From 128 to 512Kbytes embedded Flash, 64-bit wide access,

　　• 0 wait-state capability up to 24MHz

　　– up to 64Kbytes embedded SRAM

　　• System Functions

　　– Embedded voltage linear and switching regulator for single supply operation

　　– Two Power-on-Reset and Two Brown-out Detectors (BOD)

　　– Quartz or ceramic resonator oscillators: 0.6 to 30MHz main power with Failure Detection and low power 32.768 kHz for RTC or device clock

　　– High precision 4/8/12MHz factory trimmed internal RC oscillator

　　– Slow Clock Internal RC oscillator as permanent low-power mode device clock

　　– High speed 80MHz internal RC oscillator

　　– Low power 32kHz internal RC oscillator

　　– PLL up to 240MHz for device clock and for USB

　　– Digital Frequency Locked Loop (DFLL) with wide input range

　　– Up to 16 peripheral DMA (PDCA) channels

　　• Peripherals

　　– USB 2.0 Device and Embedded Host: 12 Mbps, up to 8 bidirectional Endpoints and Multi-packet Ping-pong Mode. On-Chip Transceiver

　　– Liquid Crystal Display (LCD) Module with Capacity up to 40 Segments and up to 4 Common Terminals

　　– One USART with ISO7816, IrDA®, RS-485, SPI, Manchester and LIN Mode

　　– Three USART with SPI Mode

　　– One PicoUART for extended UART wake-up capabilities in all sleep modes

　　– Windowed Watchdog Timer (WDT)

　　– Asynchronous Timer (AST) with Real-time Clock Capability, Counter or Calendar Mode Supported

　　– Frequency Meter (FREQM) for Accurate Measuring of Clock Frequency

　　– Six 16-bit Timer/Counter (TC) Channels with capture, waveform, compare and PWM mode

　　– One Master/Slave Serial Peripheral Interface (SPI) with Chip Select Signals

　　– Four Master and Two Slave Two-wire Interfaces (TWI), up to 3.4Mbit/s I2C-compatible

　　– One Advanced Encryption System (AES) with 128-bit key length

　　– One 16-channel ADC 300Ksps (ADC) with up to 12 Bits Resolution

　　– One DAC 500Ksps (DACC) with up to 10 Bits Resolution

　　– Four Analog Comparators (ACIFC) with Optional Window Detection

　　– Capacitive Touch Module (CATB) supporting up to 32 buttons

　　– Audio Bitstream DAC (ABDACB) Suitable for Stereo Audio

　　– Inter-IC Sound (IISC) Controller, Compliant with Inter-IC Sound (I2S) Specification

　　– Peripheral Event System for Direct Peripheral to Peripheral Communication

　　– 32-bit Cyclic Redundancy Check Calculation Unit (CRCCU)

　　– Random generator (TRNG)

　　– Parallel Capture Module (PARC)

　　– Glue Logic Controller (GLOC)

　　• I/O

　　– Up to 75 I/O lines with external interrupt capability (edge or level sensitivity), debouncing, glitch filtering and slew-rate control

　　– Up to Six High-drive I/O Pins

　　• Single 1.68-3.6V Power Supply

　　• Packages

　　– 100-lead LQFP, 14 x 14 mm, pitch 0.5 mm/100-ball VFBGA, 7x7 mm, pitch 0.65 mm

　　– 64-lead LQFP, 10 x 10 mm, pitch 0.5 mm/64-pad QFN 9x9 mm, pitch 0.5 mm

　　– 64-ball WLCSP, 4,314x4,434 mm, pitch 0.5 mm for SAM4LC4/2 and SAM4LS4/2 series

　　– 64-ball WLCSP, 5,270x5,194 mm, pitch 0.5 mm for SAM4LC8 and SAM4LS8 series

　　– 48-lead LQFP, 7 x 7 mm, pitch 0.5 mm/48-pad QFN 7x7 mm, pitch 0.5 mm

　　图1. ATSAM4LC2A框图

　　评估板ATSAM4L-EK

　　The ATSAM4L-EK is a reference design and development system for the 32-bit ARM® Cortex™ -M4 ATSAM4LC4C microcontroller from Atmel® Corporation. The kit is equipped with a rich set of peripherals that make the ATSAM4L-EK a perfect evaluation platform. This guide shows the user how to quickly get started with this kit.

　　This kit lets designers quickly evaluate and develop code for applications running on Atmel SAM4L microcontrollers. Board features include an embedded debugger, dedicated circuitry to measure the power consumption of your application, LCD, USB and capacitive touch functionality. It also offers expansion headers to plug in Atmel extension boards so you can easily add gyrometers, accelerometers, Wifi and Zigbee to your SAM4L-EK.

　　评估板ATSAM4L-EK包括:

　　• ATSAM4L-EK kit

　　• Board description

　　• Using the demonstration firmware

　　图2. 评估板ATSAM4L-EK外形图和元件分布图

　　评估板ATSAM4L-EK主要特性:

　　图3. 评估板ATSAM4L-EK框图

　　评估板ATSAM4L-EK材料清单: