ATmega644 Atmel Corporation, ATmega644 Datasheet - Page 238

• Manufacturer Part Number: ATmega644
• Manufacturer: Atmel Corporation

Specifications of ATmega644

• Flash (kbytes): 64 Kbytes
• Pin Count: 44
• Max. Operating Frequency: 20 MHz
• Cpu: 8-bit AVR
• # Of Touch Channels: 16
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 32
• Ext Interrupts: 32
• Usb Speed: No
• Usb Interface: No
• Spi: 3
• Twi (i2c): 1
• Uart: 1
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 8
• Adc Resolution (bits): 10
• Adc Speed (ksps): 15
• Analog Comparators: 1
• Resistive Touch Screen: No
• Temp. Sensor: No
• Crypto Engine: No
• Sram (kbytes): 4
• Eeprom (bytes): 2048
• Self Program Memory: YES
• Dram Memory: No
• Nand Interface: No
• Picopower: No
• Temp. Range (deg C): -40 to 85
• I/o Supply Class: 1.8 to 5.5
• Operating Voltage (vcc): 1.8 to 5.5
• Fpu: No
• Mpu / Mmu: no / no
• Timers: 3
• Output Compare Channels: 6
• Input Capture Channels: 1
• Pwm Channels: 6
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: Yes

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ATmega644
Figure 21-5. ADC Timing Diagram, Single Conversion
Figure 21-6. ADC Timing Diagram, Auto Triggered Conversion
Figure 21-7. ADC Timing Diagram, Free Running Conversion
Cycle Number
ADC Clock
ADSC
ADIF
ADCH
ADCL
Cycle Number
ADC Clock
Trigger
Source
ADATE
ADIF
ADCH
ADCL
Prescaler
Reset
1
Cycle Number
ADC Clock
ADSC
ADIF
ADCH
ADCL
MUX and REFS
Update
1
2
MUX and REFS
Update
2
3
Conversion
Complete
3
One Conversion
Sample & Hold
4
Sample & Hold
11
4
5
12
5
6
6
13
7
One Conversion
7
One Conversion
Next Conversion
1
8
MSB of Result
LSB of Result
8
9
2
MUX and REFS
Update
9
Conversion
10
Conversion
Complete
10
Complete
3
11
11
Sample & Hold
4
12
12
13
13
MSB of Result
LSB of Result
MSB of Result
LSB of Result
Next Conversion
1
MUX and REFS
Update
Next Conversion
2593N–AVR–07/10
1
Prescaler
Reset
2
2
3