原标题：Microchip ATmega3208 AVR MCU开发方案

　　microchip公司的ATmega3208/3209微处理器是采用AVR®处理器的megaAVR® 0系列中一员,具有硬件乘法器,工作频率高达20MHz,提供各种闪存(高达48KB),SRAM(高达6KB)和256B EEPROM,以及采用28引脚,32引脚,40引脚或48引脚封装.闪存读写周期10000次,EEPROM 100,000次, 55℃时数据保存期为40年.可配置定制逻辑(CCL)有多达四个可编查找边(LUT).器件还集成了带可选择基准输入的模拟比较器(AC),10比特150ksps ADC,5个可选择内部电压基准: 0.55V, 1.1V, 1.5V, 2.5V和4.3V,多达41个可编程I/O线,具有汽车应用的AEC-Q100规范.工作温度-40℃ 到 +125℃:本文介绍了ATmega3208主要特性,框图以及开发板AVR-BLE主要特性,电路图和PCB装配图.

　　The ATmega3208/3209 microcontrollers are part of the megaAVR® 0-series, which uses the AVR® processor with hardware multiplier running at up to 20 MHz, and offers a wide range of Flash sizes up to 48 KB, up to 6 KB of SRAM, and 256 bytes of EEPROM in 28-, 32-, 40-, or 48-pin packages. The series uses the latest technologies from Microchip with a flexible and low-power architecture, including Event System and SleepWalking, accurate analog features, and advanced peripherals.

　　The devices described in this data sheet offer 32 KB in a 28/32/48-pin package.

　　ATmega3208主要特性:

　　• AVR® CPU:

　　– Single-cycle I/O access

　　– Two-level interrupt controller

　　– Two-cycle hardware multiplier

　　• Memories:

　　– 32 KB In-system self-programmable Flash memory

　　– 256B EEPROM

　　– 6 KB SRAM

　　– Write/Erase endurance:

　　• Flash 10,000 cycles

　　• EEPROM 100,000 cycles

　　– Data retention: 40 years at 55°C

　　• System:

　　– Power-on Reset (POR) circuit

　　– Brown-out Detector (BOD)

　　– Clock options:

　　• 16/20 MHz low-power internal oscillator

　　• 32.768 kHz Ultra Low-Power (ULP) internal oscillator

　　• 32.768 kHz external crystal oscillator

　　• External clock input

　　– Single-pin Unified Program Debug Interface (UPDI)

　　– Three sleep modes:

　　• Idle with all peripherals running for immediate wake-up

　　• Standby

　　– Configurable operation of selected peripherals

　　– SleepWalking peripherals

　　• Power-Down with limited wake-up functionality

　　• Peripherals:

　　– One 16-bit Timer/Counter type A (TCA) with a dedicated period register and three compare channels

　　– Up to four 16-bit Timer/Counters type B (TCB) with input capture

　　– One 16-bit Real-Time Counter (RTC) running from an external crystal or an internal RC oscillator

　　– Up to four USARTs with fractional baud rate generator, auto-baud, and start-of-frame detection

　　– Master/slave Serial Peripheral Interface (SPI)

　　– Master/slave TWI with dual address match

　　• Can operate simultaneously as master and slave

　　• Standard mode (Sm, 100 kHz)

　　• Fast mode (Fm, 400 kHz)

　　• Fast mode plus (Fm+, 1 MHz)

　　– Event System for core independent and predictable inter-peripheral signaling

　　– Configurable Custom Logic (CCL) with up to four programmable Look-up Tables (LUT)

　　– One Analog Comparator (AC) with a scalable reference input

　　– One 10-bit 150 ksps Analog-to-Digital Converter (ADC)

　　– Five selectable internal voltage references: 0.55V, 1.1V, 1.5V, 2.5V, and 4.3V

　　– CRC code memory scan hardware

　　• Optional automatic CRC scan before code execution is allowed

　　– Watchdog Timer (WDT) with Window mode, with a separate on-chip oscillator

　　– External interrupt on all general purpose pins

　　• I/O and Packages:

　　– Up to 41 programmable I/O lines

　　– 28-pin SSOP

　　– 32-pin VQFN 5x5 and TQFP 7x7

　　– 48-pin UQFN 6x6 and TQFP 7x7

　　• Temperature Ranges:

　　– Industrial: -40℃ to +85℃

　　– Extended: -40℃ to +125℃

　　• Speed Grades -40℃ to +105℃:

　　– 0-5 MHz @ 1.8V – 5.5V

　　– 0-10 MHz @ 2.7V – 5.5V

　　– 0-20 MHz @ 4.5V – 5.5V

　　• Speed Grades -40℃ to +125℃:

　　– 0-8 MHz @ 2.7V - 5.5V

　　– 0-16 MHz @ 4.5V - 5.5V

　　• VAO variants available: Designed, manufactured, tested, and qualified in accordance with AEC-Q100 requirements for automotive applications.

　　图1. ATmega3208框图

　　开发板AVR-BLE

　　The AVR-BLE Development Board is a small and easily expandable demonstration and development platform for Bluetooth® Low Energy (BLE) solutions based on the AVR® microcontroller architecture. It is designed to demonstrate that the design of a typical BLE application can be simplified by partitioning the task into three blocks:

　　• Smart – represented by the ATmega3208 microcontroller

　　• Secure – represented by the ATECC608A secure element

　　• Connected – represented by the RN4870 BLE module

　　In addition, the AVR-BLE Development Board features the following elements:

　　• The on-board debugger (PKoB nano) supplies full programming and debugging support through Atmel Studio/Microchip MPLAB® X IDE. It also provides access to a serial port interface (serial to USB bridge) and two logic analyzer channels (debug GPIO).

　　• A mikroBUS™ socket enables the ability to expand the board capabilities with the selection from 450+ sensors

　　and actuators options offered by MikroElektronika (www.mikroe.com) via a growing portfolio of Click board™.

　　图2. 开发板AVR-BLE外形图

　　开发板AVR-BLE主要特性:

　　• ATmega3208 AVR Microcontroller

　　• Two User LEDs (Data and Error)

　　• Mechanical Button

　　• RN4870 Bluetooth Low Energy (BLE) Module

　　• MCP9844 Temperature Sensor

　　• BMA253 Acceleration Sensor

　　• ATECC608A CryptoAuthentication™ Device

　　• SST25PF040CT 4Mb Serial Flash

　　• mikroBUS Socket

　　• On-board Debugger

　　– Board identification in Atmel Studio/Microchip MPLAB® X IDE

　　– Programming and debugging

　　– Virtual serial port (USB CDC)

　　– Two logic analyzer channels (DGI GPIO)

　　• USB or Battery Powered

　　图3. 开发板AVR-BLE外形图(正面)

　　图4. 开发板AVR-BLE外形图(背面)

　　图5. 开发板AVR-BLE外形图(DT100111)