ATMEGA169 ATMEL [ATMEL Corporation], ATMEGA169 Datasheet - Page 214

• Manufacturer Part Number: ATMEGA169
• Description: 8-bit Microcontroller with 16K Bytes In-System Programmable Flash
• Manufacturer: ATMEL [ATMEL Corporation]

1/3 Duty and 1/3 Bias
1/4 Duty and 1/3 Bias
214
ATmega169/V
1/3 bias is usually recommended for LCD with three common terminals (1/3 duty).
Waveform is shown in Figure 101. SEG0 - COM0 is the voltage across a segment that is
on and SEG0-COM1 is the voltage across a segment that is off.
Figure 101. 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 Figure 102. SEG0 - COM0 is the voltage across a segment that is on and
SEG0 - COM1 is the voltage across a segment that is off.
Figure 102. Driving a LCD with Four Common Terminals
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2
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-V
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-V
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V
V
V
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V
GND
GND
GND
V
V
V
GND
V
V
V
GND
V
V
V
GND
V
V
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
Frame
Frame
Frame
Frame
SEG0
COM0
SEG0 - COM0
SEG0
COM0
SEG0 - COM0
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2
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-V
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-V
V
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GND
V
V
V
GND
V
V
V
GND
V
V
V
V
V
V
V
V
V
V
V
V
V
GND
GND
GND
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
LCD
Frame
Frame
Frame
Frame
2514P–AVR–07/06
SEG0
COM1
SEG0 - COM1
SEG0
COM1
SEG0 - COM1