ST7066U
!"Supply Voltage for LCD Drive
There are different voltages that supply to ST7066U’s pin (V1 - V5) to obtain LCD drive waveform. The relations
of the bias, duty factor and supply voltages are shown as below:
Duty Factor
1/8, 1/11
1/16
Bias
1/4
1/5
Supply Voltage
V1
V2
V3
V4
V5
Vcc - 1/4VLCD
Vcc - 1/2VLCD
Vcc - 1/2VLCD
Vcc - 3/4VLCD
Vcc - VLCD
Vcc - 1/5VLCD
Vcc - 2/5VLCD
Vcc - 3/5VLCD
Vcc - 4/5VLCD
Vcc- VLCD
VCC(+5V)
V
CC(+5V)
V
CC
V
CC
R
R
R
R
V1
V1
V2
V3
V2
V3
V
LCD
V
LCD
R
R
R
R
V4
V5
V4
V5
VR
1/4 bias
(1/8, 1/11 duty cycle)
1/5 bias
(1/16 duty cycle)
VR
-5V
-5V
V2.0
2001/03/01
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