ATmega644PR231 Atmel Corporation, ATmega644PR231 Datasheet - Page 52

• Manufacturer Part Number: ATmega644PR231
• Manufacturer: Atmel Corporation

Specifications of ATmega644PR231

• Flash (kbytes): 64 Kbytes
• Max. Operating Frequency: 20 MHz
• Max I/o Pins: 32
• Spi: 3
• Twi (i2c): 1
• Uart: 2
• Adc Channels: 8
• Adc Resolution (bits): 10
• Adc Speed (ksps): 15
• Analog Comparators: 1
• Crypto Engine: AES
• Sram (kbytes): 4
• Eeprom (bytes): 2048
• Operating Voltage (vcc): 1.8 to 3.6
• Timers: 3
• Frequency Band: 2.4 GHz
• Max Data Rate (mb/s): 2
• Antenna Diversity: Yes
• External Pa Control: Yes
• Power Output (dbm): 3
• Receiver Sensitivity (dbm): -101
• Receive Current Consumption (ma): 13.2
• Transmit Current Consumption (ma): 14.4
• Link Budget (dbm): 104

8.4
8011O–AVR–07/10
External Reset
Figure 8-2.
Figure 8-3.
An External Reset is generated by a low level on the RESET pin. Reset pulses longer than the
minimum pulse width (see
reset, even if the clock is not running. Shorter pulses are not guaranteed to generate a reset.
When the applied signal reaches the Reset Threshold Voltage – V
delay counter starts the MCU after the Time-out period – t
Figure 8-4.
INTERNAL
INTERNAL
TIME-OUT
TIME-OUT
RESET
RESET
RESET
RESET
V
V
CC
CC
CC
MCU Start-up, RESET Tied to V
MCU Start-up, RESET Extended Externally
External Reset During Operation
V
V
”System and Reset Characteristics” on page
V
POT
POT
RST
t
TOUT
CC
V
RST
ATmega164P/324P/644P
t
TOUT
TOUT
– has expired.
RST
– on its positive edge, the
331) will generate a
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