STE2001 Datasheet, PDF (13/36 Pages) STMicroelectronics – 65 X 128 SINGLE CHIP LCD CONTROLLER / DRIVER

STE2001
thus providing an 1/(n+4) ratio, with n calculated from:
n= m – 3
For m = 65, n = 5 and an 1/9 ratio is set.
For m = 33, n =3 and an 1/7 ratio is set.
The STE2001 provides three bits (BS0, BS1, BS2) for programming the desired Bias Ratio as shown below:
BS2
BS1
BS0
n
0
0
0
7
0
0
1
6
0
1
0
5
0
1
1
4
1
0
0
3
1
0
1
2
1
1
0
1
1
1
1
0
The following table Bias Level for m = 65 and m = 33 are provided:
Symbol
m = 65 (1/9)
V1
V_LCD
V2
8/9*V_LCD
V3
7/9*V_LCD
V4
2/9*V V_LCD
V5
1/9 *V_LCD
V6
V_SS
m = 33 (1/7)
V_LCD
6/7* V_LCD
5/7* V_LCD
2/7* V_LCD
1/7* V_LCD
V_SS
LCD Voltage Generation
The LCD Voltage at reference temperature (To = 35°C) can be set using the VOP register content according to
the following formula:
V_LCD(T=To) = V_LCDo = (Ai+V_OP · B) (i=0,1)
with the following values:
Symbol
Value
Unit
Note
Ao
2.90
V
PRS = 0
A1
6.91
V
PRS = 1
B
0.034
V
To
35
°C
Note that the two PRS value produces two adjacent ranges for VLCD. If the register and PRS bit are set to zero
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