PCF8811MU/2DA/1 PHILIPS [NXP Semiconductors], PCF8811MU/2DA/1 Datasheet - Page 55

• Manufacturer Part Number: PCF8811MU/2DA/1
• Description: 80 x 128 pixels matrix LCD driver
• Manufacturer: PHILIPS [NXP Semiconductors]

Philips Semiconductors
22 MODULE MAKER PROGRAMMING
The 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 pin. This pin must be made
available on the module glass but need not to be accessed
by the set maker.
The PCF8811 features 3 module maker programmable
parameters:
22.1
The first feature included is the ability to adjust the V
voltage with a 5-bit code (MMVOPCAL). This code is
implemented in twos complement notation giving rise to a
positive or negative offset to the V
same manner as the on-glass calibration pins V
2004 May 17
handbook, full pagewidth
V
Temperature coefficient selection
Seal bit.
80
LCD
V
calibration
LCD
128 pixels matrix LCD driver
calibration
MMVOPCAL [ 4:0 ]
V OS [ 4:0 ]
V PR [ 7:0 ]
OTP V LCD calibration: 5-bit offset
laser trim pins: 5-bit offset
V PR register: 8-bit value
PR
register. This is in the
range 16 to 15
range 16 to 15
range 0 to 255
usable range 32 to 255
Fig.47 V
OS
.
LCD
LCD
55
calibration.
In theory, both may be used together but it is
recommended that the V
calibration is being used. This will set them to a default
offset of zero. If both are used then the addition of the two
5-bit numbers must not exceed a 5-bit result otherwise the
resultant value will be 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 generator, V
the sum of all the calibration registers and pins. The V
equation (4) or (5) given in Section 13.10 must be
extended to include the OTP calibration, as follows;
The possible MMVOPCAL[4:0] values are the same as the
V
OS
[4:0] values; see Table 12.
V
+
LCD T
MMVOPCAL[4:0]
=
T
CUT
V OP [7:0]
range: 0 to 255
=
OS
a
+
pins are tied to V
+
V
V
OS
OP
[4:0]
to high voltage
generator
[7:0]
Product specification
MGU287
PCF8811
b
SS
when OTP
OP
, will be
LCD
(7)