ATmega329P Atmel Corporation, ATmega329P Datasheet - Page 234

• Manufacturer Part Number: ATmega329P
• Manufacturer: Atmel Corporation

Specifications of ATmega329P

• Flash (kbytes): 32 Kbytes
• Pin Count: 64
• Max. Operating Frequency: 20 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
• Segment Lcd: 100
• 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: Yes
• 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

23.3.3
23.3.4
8021G–AVR–03/11
1/3 Duty and 1/3 Bias
1/4 Duty and 1/3 Bias
Figure 23-4. Driving a LCD with Two Common Terminals
1/3 bias is usually recommended for LCD with three common terminals (1/3 duty). Waveform is
shown in
COM1 is the voltage across a segment that is off.
Figure 23-5. Driving a LCD with Three Common Terminals
1/3 bias is optimal for LCD displays with four common terminals (1/4 duty). Waveform is shown
in
the voltage across a segment that is off.
Figure
-
-
2
1
2
1
2
1
1
2
-1
1
1
/
/
/
/
/
/
/
/
3
3
3
3
3
3
3
3
-V
/
/
/
V
V
V
GND
V
V
V
GND
V
V
V
GND
V
V
2
2
2
-V
V
V
V
V
V
V
GND
GND
GND
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
23-6. SEG0 - COM0 is the voltage across a segment that is on and SEG0 - COM1 is
Figure
LCD
LCD
LCD
LCD
LCD
LCD
LCD
Frame
Frame
23-5. SEG0 - COM0 is the voltage across a segment that is on and SEG0-
Frame
Frame
SEG0
COM0
SEG0 - COM0
SEG0
COM0
SEG0 - COM0
-
-
-1
2
1
2
1
2
1
1
2
1
1
/
/
/
/
/
/
/
/
3
3
3
3
3
3
3
3
/
/
/
-V
2
2
2
V
V
V
V
V
V
V
V
V
V
V
GND
GND
GND
-V
V
GND
V
V
GND
V
V
GND
V
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
ATmega329P/3290P
Frame
Frame
Frame
Frame
SEG0
COM1
SEG0 - COM1
SEG0
COM1
SEG0 - COM1
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