PCF2113DU10 PHILIPS [NXP Semiconductors], PCF2113DU10 Datasheet - Page 9

• Manufacturer Part Number: PCF2113DU10
• Description: LCD controllers/drivers
• Manufacturer: PHILIPS [NXP Semiconductors]

Philips Semiconductors
7
7.1
The LCD supply voltage may be generated on-chip. The
V
V
temperature is given by the relationship:
V
7.1.1
Programmed value: 1 to 63. Voltage: 1.90 to 6.86 V.
T
Values producing more than 6.5 V at operating
temperature are not allowed. Operation above this
voltage may damage the device. When programming the
operating voltage the V
coefficient must be taken into account.
Values below 2.2 V are below the specified operating
range of the chip and are therefore not allowed.
Value 0 for V
(i.e. V
Usually register V
character mode and register V
mode.
When V
decoupled to V
Table 1 Bias levels as a function of multiplex rate; note 1
Note
1. The values in the table are given relative to V
2001 Dec 19
MULTIPLEX
ref
LCD
A
OP(nom)
LCD controllers/drivers
and V
= 27 C.
FUNCTIONAL DESCRIPTION
RATE
1 : 18
1 : 9
1 : 2
generator is controlled by two internal 6-bit registers:
A
LCD supply voltage generator
= 0 in character mode, V
LCD
= (integer value of register
P
B
. The nominal LCD operating voltage at room
ROGRAMMING RANGES
is generated on-chip the V
A
and V
SS
OF LEVELS
NUMBER
A
with a suitable capacitor.
is programmed with the voltage for
B
5
5
4
switches the generator off
LCD
tolerance and temperature
B
with the voltage for icon
B
= 0 in icon mode).
V
V
V
V
LCD
LCD
LCD
1
0.08) + 1.82
LCD
pins should be
LCD
V
3
3
2
/
/
/
2
4
4
3
V
SS
9
, e.g.
The generated V
temperature compensated. When the V
the direct mode are switched off, an external voltage may
be supplied at connected pins V
V
During direct mode (program DM register bit) the internal
V
is directly connected to V
consumption during icon mode and Mux 1 : 9 (depending
on V
The V
valid range (2.2 to 4 V), the required peak voltage
V
7.2
The intermediate bias voltages for the LCD display are
also generated on-chip. This removes the need for an
external resistive bias chain and significantly reduces the
system current consumption. The optimum value of V
depends on the multiplex rate, the LCD threshold voltage
(V
scheme for 1 : 18 maximum rate allows V
most LCD liquids. The intermediate bias levels for the
different multiplex rates are shown in Table 1. These bias
levels are automatically set to the given values when
switching to the corresponding multiplex rate.
LCD2
LCD
OP
th
3
) and the number of bias levels. Using a 5-level bias
/
V
DD2
= 6.5 V can be generated at any time.
1
1
2
4
generator is turned off and the V
/
/
/
LCD
3
2
2
3
may be higher or lower than V
means
LCD bias voltage generator
value and LCD liquid properties).
generator ensures that, as long as V
3
/
4
LCD
(V
V
1
1
1
/
/
/
is independent of V
4
2
2
3
LCD
DD2
V
. This reduces the current
SS
).
LCD1
V
1
1
1
/
/
/
5
and V
4
4
3
DD2
Product specification
LCD2
PCF2113x
LCD
.
DD
LCD
LCD2
output voltage
generator and
and is
< 5 V for
. V
DD
V
V
V
LCD1
V
is in the
SS
SS
SS
6
and
LCD