OM6211 NXP Semiconductors, OM6211 Datasheet - Page 10

• Manufacturer Part Number: OM6211
• Description: 48 X 84 Dot Matrix Lcd Driver
• Manufacturer: NXP Semiconductors

Philips Semiconductors
9.9
The bias voltage levels are set in the ratio of
R - R - nR - R - R. Different multiplex rates require
different factors of n. This is programmed by BS
For optimum bias values, n can be calculated from the
following equation:
Changing the bias system from the optimum setting will
have a consequence on the contrast and viewing angle.
Table 1 Programming the required bias system
Table 2 LCD bias voltages for
9.10
The OM6211 incorporates a software configurable voltage multiplier. After reset (RES) the voltage multiplier is set to
4V
Table 3 HV generator multiplication
2002 Jan 17
n
48
=
DD2
. Other voltage multiplier factors are set via the serial interface (S
Mux rate 3
Bias system
Voltage multiplier control
BS
0
1
1
84 dot matrix LCD driver
SYMBOL
2
V1
V2
V3
V4
V5
V6
–
S
0
0
1
1
; where Mux rate is 48.
1
BS
1
0
0
1
1
6
bias,
FOR
1
5
4
2
1
7
V
6
6
6
6
V
1
bias and
V
V
V
V
LCD
SS
6
LCD
LCD
LCD
LCD
BIAS
BS
2
1
0
1
to BS
0
1
8
0
bias.
.
10
S
0
1
0
1
0
One reason to depart from the optimum would be to
reduce the required V
contrast and V
application.
In the OM6211 one of three possible values of the bias
system can be selected. The value
BIAS VOLTAGE
FOR
n
4
3
2
6
5
2
1
1
V
7
7
7
7
V
and S
1
V
V
V
V
LCD
SS
7
LCD
LCD
LCD
LCD
LCD
BIAS
0
must be found for any particular
).
LCD
BIAS MODE
voltage. A compromise between
1
1
1
8
7
6
MULTIPLICATION
not available
2V
3V
4V
1
FOR
Product specification
7
DD2
DD2
DD2
is default.
7
6
2
1
1 : 55 and 1 : 48
TYPICAL MUX
V
8
8
8
8
V
1
V
V
V
V
LCD
OM6211
SS
8
LCD
LCD
LCD
LCD
RATES
BIAS
1 : 33
1 : 24