
347
13.3.3
Luminance Adjustment Function (V0 Pin)
Figure 13-13 shows a detailed block diagram of the LCD drive power supply unit.
The voltage output to the V
0
pin is either V
CC
or the 5 V output from the step-up conversion power
supply circuit. When either of these voltages is used directly as the LCD drive power supply, the
V
0
and V
1
pins should be shorted. Also, connecting a variable resistance, R, between the V
0
and
V
1
pins makes it possible to adjust the voltage applied to the V
1
pin, and so to provide luminance
adjustment for the LCD panel.
Figure 13-13 LCD Drive Power Supply Unit
Power supply
selector
*
Step-up constant-
voltage power supply
*
Applies to the H8/3867 Series
V
CC
V
SS
5V
V
0
V
1
V
2
V
3
R