ATmega325 Atmel Corporation, ATmega325 Datasheet - Page 234

• 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

Table 25-5.
2570N–AVR–05/11
Signal Name
COMP
ACLK
ACTEN
ADCBGEN
ADCEN
AMPEN
DAC_9
DAC_8
DAC_7
DAC_6
DAC_5
DAC_4
DAC_3
DAC_2
DAC_1
DAC_0
EXTCH
GNDEN
HOLD
IREFEN
MUXEN_7
MUXEN_6
MUXEN_5
MUXEN_4
MUXEN_3
MUXEN_2
MUXEN_1
MUXEN_0
Boundary-scan Signals for the ADC
Direction as seen
from the ADC
Output
Input
Input
Input
Input
Input
Input
Input
Input
Input
Input
Input
Input
Input
Input
Input
Input
Input
Input
Input
Input
Input
Input
Input
Input
Input
Input
Input
Description
Comparator Output
Clock signal to differential amplifier
implemented as Switch-cap filters
Enable path from differential amplifier to
the comparator
Enable Band-gap reference as negative
input to comparator
Power-on signal to the ADC
Power-on signal to the differential amplifier
Bit 9 of digital value to DAC
Bit 8 of digital value to DAC
Bit 7 of digital value to DAC
Bit 6 of digital value to DAC
Bit 5 of digital value to DAC
Bit 4 of digital value to DAC
Bit 3 of digital value to DAC
Bit 2 of digital value to DAC
Bit 1 of digital value to DAC
Bit 0 of digital value to DAC
Connect ADC channels 0 - 3 to by-pass
path around differential amplifier
Ground the negative input to comparator
when true
Sample & Hold signal. Sample analog
signal when low. Hold signal when high. If
differential amplifier are used, this signal
must go active when ACLK is high.
Enables Band-gap reference as AREF
signal to DAC
Input Mux bit 7
Input Mux bit 6
Input Mux bit 5
Input Mux bit 4
Input Mux bit 3
Input Mux bit 2
Input Mux bit 1
Input Mux bit 0
(1)
ATmega325/3250/645/6450
Recommended
Input when not
in use
0
0
0
0
0
0
1
0
0
0
0
0
0
0
0
0
1
0
1
0
0
0
0
0
0
0
0
1
Output Values when
recommended inputs are used,
and CPU is not using the ADC
0
0
0
0
0
0
1
0
0
0
0
0
0
0
0
0
1
0
1
0
0
0
0
0
0
0
0
1
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