PCF8811U/2DA/1 NXP [NXP Semiconductors], PCF8811U/2DA/1 Datasheet - Page 69

• Manufacturer Part Number: PCF8811U/2DA/1
• Description: 80 x 128 pixels matrix LCD driver
• Manufacturer: NXP [NXP Semiconductors]

NXP Semiconductors
18. Support information
PCF8811_4
Product data sheet
18.1.1 V
18.1 Module maker programming
One Time Programmable (OTP) technology is implemented on the PCF8811. It enables
the module maker to program some extended features of the PCF8811 after it has been
assembled on an LCD module. Programming is made under the control of the interfaces
and the use of one special pad. This pad must be made available on the module glass but
need not be accessed by the set maker.
The PCF8811 features 3 parameters programmable by the module maker:
The first feature included is the ability to adjust the V
(MMVOPCAL). This code is implemented in two’s complement notation giving rise to a
positive or negative offset to the V
calibration pads V
In theory, both may be used together but it is recommended that the V
V
are used then the addition of the two 5-bit numbers must not exceed a 5-bit result,
otherwise the resultant value is undefined. The final adder in the circuit has underflow and
overflow protection. In the event of an overflow, the output will be clamped to 255; during
an underflow the output will be clamped to 0.
The final control to the high voltage multiplier, V
registers and pads. The V
Section 12.10.2
The possible values for MMVOPCAL[4:0] and V
Table 36.
V
Binary
0 0000
0 0001
0 0010
0 0011
0 0100
0 0101
0 0110
0 0111
0 1000
0 1001
•
•
•
SS
LCD
LCD T
V
Temperature coefficient selection
Seal bit
when OTP calibration is being used. This sets them to a default offset of zero. If both
LCD
calibration
=
calibration
T
V
CUT
OS
/MMVOPCAL values in two’s complement notation
=
must be extended to include the OTP calibration, as follows:
OS
a
+
.
Decimal
0
+1
+2
+3
+4
+5
+6
+7
+8
+9
V
Rev. 04 — 27 June 2008
OS
LCD
[4:0]
Equation 4
+
MMVOPCAL[4:0]
PR
register. This is in the same manner as the on-glass
or
Equation 5
Binary
1 1111
1 1110
1 1101
1 1100
1 1011
1 1010
1 1001
1 1000
1 0111
1 0110
OP
OS
, is the sum of all the calibration
[4:0] values are given in
+
LCD
V
80 x 128 pixels matrix LCD driver
OP
given in
voltage with a 5-bit code
[7:0]
Section 12.10.1
b
Decimal
1
2
3
4
5
6
7
8
9
10
OS
PCF8811
© NXP B.V. 2008. All rights reserved.
pads are tied to
Table
or
36.
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