ATMEGA644-20AU Atmel, ATMEGA644-20AU Datasheet - Page 22

• Manufacturer Part Number: ATMEGA644-20AU
• Description: IC AVR MCU FLASH 64K 44TQFP
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA644-20AU

• 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): 2.7 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: 2-Wire/SPI/USART
• Maximum Clock Frequency: 20 MHz
• Number Of Programmable I/os: 32
• Number Of Timers: 3
• Operating Supply Voltage: 2.7 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, ATAVRRZ541, ATAVRRAVEN, ATAVRRZRAVEN, ATAVRRZUSBSTICK, ATAVRRZ201
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 8-ch x 10-bit
• Cpu Family: ATmega
• Device Core: AVR
• Device Core Size: 8b
• Frequency (max): 20MHz
• Total Internal Ram Size: 4KB
• # I/os (max): 32
• Number Of Timers - General Purpose: 3
• Operating Supply Voltage (typ): 3.3/5V
• Operating Supply Voltage (max): 5.5V
• Operating Supply Voltage (min): 2.7V
• Instruction Set Architecture: RISC
• Operating Temp Range: -40C to 85C
• Operating Temperature Classification: Industrial
• Mounting: Surface Mount
• Pin Count: 44
• Package Type: TQFP
• Package: 44TQFP
• Family Name: ATmega
• Maximum Speed: 20 MHz
• For Use With: ATSTK600-TQFP44 - STK600 SOCKET/ADAPTER 44-TQFPATSTK600-DIP40 - STK600 SOCKET/ADAPTER 40-PDIP770-1007 - ISP 4PORT ATMEL AVR MCU SPI/JTAG770-1005 - ISP 4PORT FOR ATMEL AVR MCU JTAG770-1004 - ISP 4PORT FOR ATMEL AVR MCU SPIATAVRISP2 - PROGRAMMER AVR IN SYSTEM
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

9.11
9.12
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2593NS–AVR–07/10
Rev. 2593D - 04/06
Rev. 2593C - 03/06
Rev. 2593B - 03/06
Rev. 2593A-06/05
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Initial revision.
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Added “Not recommended in new designs”.
Removed RAMPZ– Extended Z-pointer Register for ELPM/SPM from datasheet.
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Updated code example in
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Removed the occurancy of ATmega164 and ATmega324.
Updated Adresses in Registers.
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Updated SRAM sizes in
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Updated Register bit Discription in
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Changed name from “SFIOR“ to “ADCSRB“ in
”Bit 5 – ADATE: ADC Auto Trigger Enable” on page 250
Reserved Bits” on page
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Updated Example in
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1 on page
322,
Table 27-1 on page
”Bit 6 – ACBG: Analog Comparator Bandgap Select” on page
”Prescaling and Conversion Timing” on page
Table 10-1 on page
”Setting the Boot Loader Lock Bits by SPM” on page
”Register Summary” on page
”Architectural Overview” on page
”I/O Memory” on page
”PRR – Power Reduction Register” on page
”Signature Bytes” on page
”DC Characteristics” on page
”Typical Characteristics” on page
”Register Summary” on page
Figure 6-2 on page 18
”Errata” on page
Table 9-1 on page
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Table 25-7 on page
”Overview of the TWI Module” on page
”Supply Current of IO modules” on page
”Analog-to-digital Converter” on page
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”SRAM Data Memory” on page
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”Interrupt Vectors in ATmega644” on page
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Table 27-2 on page
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Table 9-4 on page 51,Table 10-1 on page 55,Table 23-
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”Register Description” on page
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Figure 21-1 on page
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Table 25-15 on page 299,Table 26-6 on page
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”Starting a Conversion” on page
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