ATmega325 Atmel Corporation, ATmega325 Datasheet - Page 205

• Manufacturer Part Number: ATmega325
• Manufacturer: Atmel Corporation

Specifications of ATmega325

• Flash (kbytes): 32 Kbytes
• Pin Count: 64
• Max. Operating Frequency: 16 MHz
• Cpu: 8-bit AVR
• # Of Touch Channels: 16
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 54
• Ext Interrupts: 17
• Usb Speed: No
• Usb Interface: No
• Spi: 2
• 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): 2
• Eeprom (bytes): 1024
• 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: 4
• Input Capture Channels: 1
• Pwm Channels: 4
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: Yes

2570N–AVR–05/11
with Auto triggering from a source other than the ADC Conversion Complete, each conversion
will require 25 ADC clocks. This is because the ADC must be disabled and re-enabled after
every conversion.
In Free Running mode, a new conversion will be started immediately after the conversion com-
pletes, while ADSC remains high. For a summary of conversion times, see
Figure 23-4. ADC Timing Diagram, First Conversion (Single Conversion Mode)
Figure 23-5. ADC Timing Diagram, Single Conversion
Figure 23-6. ADC Timing Diagram, Auto Triggered Conversion
Cycle Number
ADC Clock
Trigger
Source
ADATE
ADIF
ADCH
ADCL
Cycle Number
ADC Clock
ADSC
ADIF
ADCH
ADCL
Cycle Number
ADC Clock
ADEN
ADSC
ADIF
ADCH
ADCL
Prescaler
Reset
1
1
2
MUX and REFS
Update
MUX and REFS
Update
1
2
MUX and REFS
Update
12
2
3
13
Sample & Hold
3
4
Sample &
Hold
14
4
5
15
5
6
Sample & Hold
16
6
First Conversion
17
7
ATmega325/3250/645/6450
One Conversion
18
7
8
One Conversion
19
8
9
20
9
10
Conversion
Complete
21
10
Conversion
11
Complete
22
Conversion
Complete
11
23
12
24
12
13
25
13
Sign and MSB of Result
Sign and MSB of Result
Table
LSB of Result
Next Conversion
Sign and MSB of Result
1
Next
Conversion
1
LSB of Result
LSB of Result
2
2
23-1.
MUX and REFS
Update
Next Conversion
MUX and REFS
Update
1
Prescaler
Reset
3
3
2
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