LC75838W Datasheet, PDF (20/36 Pages) ON Semiconductor – Duty General-Purpose LCD Driver

LC75838W
Control Data Functions
1. PC1 to PC3: General-purpose output port state setting data
These control data bits set the states of the general-purpose output ports P1 to P3.
Output pin
P1
P2
P3
General-purpose output port state setting data
PC1
PC2
PC3
For example, if PC1 and PC2 are set to 1, and PC3 is set to 0, then the output pins P1 and P2 will output high levels
(VDD) and the output pin P3 will output low level (VSS).
2. CT0 to CT3, CTC: Display contrast setting data
These control data bits set the display contrast.
CT0 to CT3: Display contrast setting (11 steps)
CT0
CT1
CT2
CT3
LCD drive 4/4 bias voltage supply VLCD0 level
0
0
0
0
0.94VLCD=VLCD-(0.03VLCD2)
1
0
0
0
0.91VLCD=VLCD-(0.03VLCD3)
0
1
0
0
0.88VLCD=VLCD-(0.03VLCD4)
1
1
0
0
0.85VLCD=VLCD-(0.03VLCD5)
0
0
1
0
0.82VLCD=VLCD-(0.03VLCD6)
1
0
1
0
0.79VLCD=VLCD-(0.03VLCD7)
0
1
1
0
0.76VLCD=VLCD-(0.03VLCD8)
1
1
1
0
0.73VLCD=VLCD-(0.03VLCD9)
0
0
0
1
0.70VLCD=VLCD-(0.03VLCD10)
1
0
0
1
0.67VLCD=VLCD-(0.03VLCD11)
0
1
0
1
0.64VLCD=VLCD-(0.03VLCD12)
CTC: Display contrast adjustment circuit state setting
CTC
Display contrast adjustment circuit state
0
The display contrast adjustment circuit is disabled, and the VLCD0 pin level is forced to the VLCD level.
1
The display contrast adjustment circuit operates and the display contrast is adjusted.
Note that although the display contrast can be adjusted by operating the built-in display contrast adjustment circuit, it
is also possible to apply fine adjustments to the contrast by connecting an external variable resistor to the VLCD4 pin
and modifying the VLCD4 pin voltage. However, the following conditions must be met: (VLCD0 - VLCD4)  4.5V,
and 1.5V  VLCD4  0V.
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