ATMEGA644PA-AU Atmel, ATMEGA644PA-AU Datasheet - Page 573

• Manufacturer Part Number: ATMEGA644PA-AU
• Description: IC MCU 8BIT 64KB FLASH 44TQFP
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA644PA-AU

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 20MHz
• Connectivity: I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 32
• 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: 44-TQFP, 44-VQFP
• Processor Series: ATMEGA64x
• Core: AVR8
• Data Bus Width: 8 bit
• Data Ram Size: 4 KB
• Interface Type: SPI, TWI, UART
• Maximum Clock Frequency: 20 MHz
• Number Of Programmable I/os: 32
• Operating Supply Voltage: 1.8 V to 5.5 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: EWAVR, EWAVR-BL
• Development Tools By Supplier: ATAVRDRAGON, ATSTK500, ATSTK600, ATAVRISP2, ATAVRONEKIT
• Minimum Operating Temperature: - 40 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Table of Contents
8272A–AVR–01/10
1
2
3
4
5
6
7
8
164A/164PA/324A/324PA/644A/644PA/1284/1284P
Features ..................................................................................................... 1
Pin Configurations ................................................................................... 2
Overview ................................................................................................... 5
Resources ................................................................................................. 9
About Code Examples ............................................................................. 9
Data Retention .......................................................................................... 9
AVR CPU Core ........................................................................................ 10
AVR Memories ........................................................................................ 19
System Clock and Clock Options ......................................................... 30
1.1Pinout - PDIP/TQFP/VQFN/QFN/MLF for
1.2Pinout - DRQFN for ATmega164A/164PA/324A/324PA ...........................................3
1.3Pinout - VFBGA for ATmega164A/164PA/324A/324PA ............................................4
2.1Block Diagram ...........................................................................................................5
2.2Comparison Between ATmega164A, ATmega164PA, ATmega324A, ATmega324PA,
2.3Pin Descriptions ........................................................................................................7
6.1Overview .................................................................................................................10
6.2ALU – Arithmetic Logic Unit ....................................................................................11
6.3Status Register ........................................................................................................11
6.4General Purpose Register File ................................................................................13
6.5Stack Pointer ...........................................................................................................14
6.6Instruction Execution Timing ...................................................................................15
6.7Reset and Interrupt Handling ..................................................................................16
7.1Overview .................................................................................................................19
7.2In-System Reprogrammable Flash Program Memory .............................................19
7.3SRAM Data Memory ...............................................................................................20
7.4EEPROM Data Memory ..........................................................................................22
7.5I/O Memory ..............................................................................................................23
7.6Register Description ................................................................................................24
8.1Clock Systems and their Distribution .......................................................................30
8.2Clock Sources .........................................................................................................31
ATmega164A/164PA/324A/324PA/644A/644PA/1284/1284P 2
ATmega644A, ATmega644PA, ATmega1284 and ATmega1284P 6
i