ATMEGA644P-20AU Atmel, ATMEGA644P-20AU Datasheet - Page 295

• Manufacturer Part Number: ATMEGA644P-20AU
• Description: IC MCU AVR 64K FLASH 44-TQFP
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA644P-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, UART
• Maximum Clock Frequency: 20 MHz
• Number Of Programmable I/os: 32
• Number Of Timers: 3
• Operating Supply Voltage: 4.5 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
• On-chip Adc: 10 bit, 8 channel
• A/d Inputs: 8-Channel, 10-Bit
• Cpu Speed: 20 MIPS
• Eeprom Memory: 2K Bytes
• Input Output: 32
• Interface: 2-Wire/JTAG/SPI/USART
• Memory Type: Flash
• Number Of Bits: 8
• Package Type: 44-pin TQFP
• Programmable Memory: 64K Bytes
• Timers: 2-8-bit, 1-16-bit
• Voltage, Range: 2.7-5.5 V
• 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
• Controller Family/series: AVR MEGA
• No. Of I/o's: 32
• Eeprom Memory Size: 2KB
• Ram Memory Size: 4KB
• Rohs Compliant: Yes
• 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

8011O–AVR–07/10
Table 24-4.
Note:
Table 24-5.
Note:
The status of the Fuse bits is not affected by Chip Erase. Note that the Fuse bits are locked if
Lock bit1 (LB1) is programmed. Program the Fuse bits before programming the Lock bits.
Fuse High Byte
OCDEN
JTAGEN
SPIEN
WDTON
EESAVE
BOOTSZ1
BOOTSZ0
BOOTRST
Fuse Low Byte
CKDIV8
CKOUT
SUT1
SUT0
CKSEL3
CKSEL2
CKSEL1
CKSEL0
(1)
1. The SPIEN Fuse is not accessible in serial programming mode.
2. The default value of BOOTSZ1..0 results in maximum Boot Size. See
3. See
4. Never ship a product with the OCDEN Fuse programmed regardless of the setting of Lock bits
1. The default value of SUT1..0 results in maximum start-up time for the default clock source.
2. The default setting of CKSEL3..0 results in internal RC Oscillator @ 8 MHz. See
3. The CKOUT Fuse allow the system clock to be output on PORTB1. See
4. See
(3)
(4)
(4)
(3)
for details.
and JTAGEN Fuse. A programmed OCDEN Fuse enables some parts of the clock system to
be running in all sleep modes. This may increase the power consumption.
See
page 30
on page 38
Fuse High Byte
Fuse Low Byte
”WDTCSR – Watchdog Timer Control Register” on page 59
”System and Reset Characteristics” on page 331
”System Clock Prescaler” on page 38
for details.
Bit No
for details.
7
6
5
4
3
2
1
0
Bit No
7
6
5
4
3
2
0
1
Description
Enable OCD
Enable JTAG
Enable Serial Program and Data
Downloading
Watchdog Timer always on
EEPROM memory is preserved
through the Chip Erase
Select Boot Size (see
details)
Select Boot Size (see
details)
Select Reset Vector
Description
Divide clock by 8
Clock output
Select start-up time
Select start-up time
Select Clock source
Select Clock source
Select Clock source
Select Clock source
ATmega164P/324P/644P
for details.
Table 24-9
Table 24-9
for details.
for
for
Default Value
1 (unprogrammed, OCD
disabled)
0 (programmed, JTAG enabled)
0 (programmed, SPI prog.
enabled)
1 (unprogrammed)
1 (unprogrammed, EEPROM
not preserved)
0 (programmed)
0 (programmed)
1 (unprogrammed)
Default Value
0 (programmed)
1 (unprogrammed)
1 (unprogrammed)
0 (programmed)
0 (programmed)
0 (programmed)
1 (unprogrammed)
0 (programmed)
for details.
Table 23-7 on page 288
”Clock Output Buffer”
(2)
(2)
(1)
(2)
(2)
(2)
Table 6-1 on
(1)
(2)
295