hd66100 Renesas Electronics Corporation., hd66100 Datasheet - Page 354

• Manufacturer Part Number: hd66100
• Description: H8/3867 Series
• Manufacturer: Renesas Electronics Corporation.

13.3
13.3.1
To perform LCD display, the hardware and software related items described below must first be
determined.
1. Hardware settings
a. Using 1/2 duty
b. Large-panel display
c. Luminance adjustment function (V
d. LCD drive power supply setting
When 1/2 duty is used, interconnect pins V
As the impedance of the built-in power supply split-resistance is large, it may not be
suitable for driving a large panel. If the display lacks sharpness when using a large panel,
refer to section 13.3.7, Boosting the LCD Drive Power Supply. When static or 1/2 duty is
selected, the common output drive capability can be increased. Set CMX to 1 when
selecting the duty cycle. In this mode, with a static duty cycle pins COM
the same waveform, and with 1/2 duty the COM
COM
Connecting a resistance between the V
For details, see 13.3.3, Luminance Adjustment Function (V
With the H8/3867 Series, there are two ways of providing LCD power: by using the on-
chip power supply circuit, or by using an external circuit. With the H8/3867 Series, the on-
chip power supply circuit allows the selection of either the power supply voltage (V
a step-up constant voltage (5 V). For details of the step-up constant-voltage power supply,
see 13.3.4, Step-Up Constant-Voltage (5 V) Power Supply.
Operation
Settings up to LCD Display
Figure 13.3 Handling of LCD Drive Power Supply when Using 1/2 Duty
1
, and the COM
2
waveform is output from pins COM
0
pin)
V
V
0
CC
SS
and V
2
and V
1
pins enables the luminance to be adjusted.
1
V
V
V
V
waveform is output from pins COM
3
0
1
2
3
as shown in figure 13.3.
4
0
and COM
Pin).
3
.
4
to COM
1
CC
output
2
) or
and
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