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EPSON
E0C6006 TECHNICAL MANUAL
CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (LCD Driver)
4.7 LCD Driver
4.7.1 Configuration of LCD driver
The E0C6006 has four common terminals (COM0–COM3) and 20 segment terminals (SEG0–SEG19), so
that an LCD with a maximum of 80 (20
×
4) segments can be driven.
The driving method is 1/4 duty (1/3 duty can also be selected by mask option) dynamic drive, adopting
the four types of potential, V
DD
, V
L1
, V
L2
and V
L3
.
The power for driving the LCD is generated by the internal circuit so that there is no need to apply power
especially from outside.
The frame frequency is 32 Hz for 1/4 duty and 42.7 Hz for 1/3 duty (in the case of f
OSC1
= 32.768 kHz).
Figures 4.7.1.1 and 4.7.1.2 show the drive waveform for 1/3 duty and 1/4 duty.
Table 4.7.1.1 LCD drive mode options
Duty
1/4
1/3
COM used
COM0–COM3
COM0–COM2
Max. number of segments
80 (20
×
4)
60 (20
×
3)
Frame frequency
*
32 Hz
42.7 Hz
∗
When f
OSC1
= 32 kHz
COM0
COM1
COM2
COM3
V
V
V
V
DD
L1
L2
L3
V
V
V
V
DD
L1
L2
L3
Off
On
SEG0
–SEG19
Frame frequency
LCD status
COM0
COM1
COM2
SEG0–19
Fig. 4.7.1.1 Drive waveform for 1/3 duty