Fig. 2.25 Connection Examples For Supply Power For Driving Lcd - Fujitsu F2MC-8L Family series Hardware Manual

Peripherals
HARDWARE CONFIGURATION
(7) Voltage setting at power pins (V3, V2 and V1) for driving LCD
Set the voltages at the LCD power pins (V3, V2 and V1) as shown below.
1/2 bias
1/3 bias
A connection example for supply power to drive the LCD is shown in
Fig. 2.25.
2R
V3
R
V2
V1
R
1/2 bias

Fig. 2.25 Connection Examples for Supply Power for Driving LCD

Note: To set a 1/2 bias when using the external dividing resistor (ladder
circuit), short-circuit the pins V2 and V1.
Built-in voltage dividing resistor
The built-in voltage dividing resistors are connected as shown in Fig. 2.26.
Writing 1 at the VSEL bit connects the built-in voltage dividing resistors.
Therefore, write 1 at the VSEL bit to connect the resistors and set 0 to
disconnect the resistors.
The built-in voltage dividing circuit is connected to the V
transistor within chip. Therefore, the current flowing into the resistor can
be cut when the LCD stops.
2– 67
V3 V2
V 1/2 V
LCD LCD
V 2/3 V
LCD LCD
V
LCD
V3
V2
V
LCD
V1
V1
1/2 V
LCD
1/3 V
LCD
: LCD operating voltage
2R
R
R
V
LCD
R
1/3 bias
through the
SS