ATMEGA644PA-AU Atmel, ATMEGA644PA-AU Datasheet - Page 7

• 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

2.3
2.3.1
2.3.2
2.3.3
2.3.4
2.3.5
2.3.6
8272AS–AVR–01/10
Pin Descriptions
VCC
GND
Port A (PA7:PA0)
Port B (PB7:PB0)
Port C (PC7:PC0)
Port D (PD7:PD0)
Digital supply voltage.
Ground.
Port A serves as analog inputs to the Analog-to-digital Converter.
Port A also serves as an 8-bit bi-directional I/O port with internal pull-up resistors (selected for
each bit). The Port A output buffers have symmetrical drive characteristics with both high sink
and source capability. As inputs, Port A pins that are externally pulled low will source current if
the pull-up resistors are activated. The Port A pins are tri-stated when a reset condition becomes
active, even if the clock is not running.
P o r t A a l s o s e r v e s t h e f u n c t i o n s o f v a r i o u s s p e c i a l f e a t u r e s o f t h e
ATmega164A/164PA/324A/324PA/644A/644PA/1284/1284P as listed on
Port B is an 8-bit bi-directional I/O port with internal pull-up resistors (selected for each bit). The
Port B output buffers have symmetrical drive characteristics with both high sink and source
capability. As inputs, Port B pins that are externally pulled low will source current if the pull-up
resistors are activated. The Port B pins are tri-stated when a reset condition becomes active,
even if the clock is not running.
P o r t B a l s o s e r v e s t h e f u n c t i o n s o f v a r i o u s s p e c i a l f e a t u r e s o f t h e
ATmega164A/164PA/324A/324PA/644A/644PA/1284/1284P as listed on
Port C is an 8-bit bi-directional I/O port with internal pull-up resistors (selected for each bit). The
Port C output buffers have symmetrical drive characteristics with both high sink and source
capability. As inputs, Port C pins that are externally pulled low will source current if the pull-up
resistors are activated. The Port C pins are tri-stated when a reset condition becomes active,
even if the clock is not running.
Port C also serves the functions of the JTAG interface, along with special features of the
ATmega164A/164PA/324A/324PA/644A/644PA/1284/1284P as listed on
Port D is an 8-bit bi-directional I/O port with internal pull-up resistors (selected for each bit). The
Port D output buffers have symmetrical drive characteristics with both high sink and source
capability. As inputs, Port D pins that are externally pulled low will source current if the pull-up
resistors are activated. The Port D pins are tri-stated when a reset condition becomes active,
even if the clock is not running.
P o r t D a l s o s e r v e s t h e f u n c t i o n s o f v a r i o u s s p e c i a l f e a t u r e s o f t h e
ATmega164A/164PA/324A/324PA/644A/644PA/1284/1284P as listed on
164A/164PA/324A/324PA/644A/644PA/1284/1284P
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