ATMEGA645A-AU Atmel, ATMEGA645A-AU Datasheet - Page 673

• Manufacturer Part Number: ATMEGA645A-AU
• Description: IC MCU AVR 64K FLASH 64TQFP
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA645A-AU

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 16MHz
• Connectivity: SPI, UART/USART, USI
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 54
• Program Memory Size: 64KB (32K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 2K x 8
• Ram Size: 4K x 8
• Voltage - Supply (vcc/vdd): 1.8 V ~ 5.5 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 64-TQFP
• Processor Series: ATmega
• Core: AVR
• Data Bus Width: 8 bit
• Data Ram Size: 4 KB
• Interface Type: SPI, USART
• Maximum Clock Frequency: 16 MHz
• Number Of Programmable I/os: 54
• Number Of Timers: 3
• Operating Supply Voltage: 3.3 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Minimum Operating Temperature: - 40 C
• Operating Temperature Range: - 40 C to + 85 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Table of Contents
8285B–AVR–03/11
ATmega165A/165PA/325A/325PA/3250A/3250PA/6
1
2
3
4
5
6
7
8
Features ..................................................................................................... 1
Pin Configurations ................................................................................... 2
Overview ................................................................................................... 4
Resources ................................................................................................. 9
Data Retention .......................................................................................... 9
About Code Examples ............................................................................. 9
AVR CPU Core ........................................................................................ 10
AVR Memories ........................................................................................ 18
System Clock and Clock Options ......................................................... 29
1.1Pinout - TQFP and QFN/MLF ....................................................................................2
1.2Pinout - 100A (TQFP) ................................................................................................3
2.1Block Diagram ...........................................................................................................4
2.2Comparison Between
2.3Pin Descriptions ........................................................................................................6
6.1Introduction ..............................................................................................................10
6.2Architectural Overview ............................................................................................10
6.3ALU – Arithmetic Logic Unit ....................................................................................11
6.4AVR Status Register ...............................................................................................11
6.5General Purpose Register File ................................................................................13
6.6Stack Pointer ...........................................................................................................14
6.7Instruction Execution Timing ...................................................................................15
6.8Reset and Interrupt Handling ..................................................................................16
7.1In-System Reprogrammable Flash Program Memory .............................................18
7.2SRAM Data Memory ...............................................................................................19
7.3EEPROM Data Memory ..........................................................................................21
7.4I/O Memory ..............................................................................................................25
7.5General Purpose I/O Registers ...............................................................................25
7.6Register Description ................................................................................................26
8.1Clock Systems and their Distribution .......................................................................29
8.2Clock Sources .........................................................................................................30
8.3Default Clock Source ...............................................................................................31
ATmega165A/165PA/325A/325PA/3250A/3250PA/645A/645P/6450A/6450P 6
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