S1D15714 Epson Company, S1D15714 Datasheet - Page 20

• Manufacturer Part Number: S1D15714
• Description: a single chip MLS driver
• Manufacturer: Epson Company

6.6 Power supply circuit
This is a power supply circuit to generate voltage required for liquid crystal drive, and is characterized by a low power
consumption. It consists of a step-up circuit, voltage regulating circuit and liquid crystal drive voltage generating
circuit, and is enabled only during master operation. The power supply circuit uses the power control set command to
provide an on/off control of step-up circuit, voltage regulating circuit and liquid crystal drive potential generating
circuit. This allows a combined use of the external power supply and part of built-in power supply functions. Table
6.7 shows functions controlled by the 3-bit data of the control set command, and Table 6.8 shows reference
combinations. Also, by use of the magnification of amplification changing over command, it is possible to select the
amplifying magnification from five different steps. The power supply circuit is enabled only during master operation.
Table 6.7 Respective Bit Control Contents by Power Control Set Command
Table 6.8 Reference combination
Rev. 1.0
* Any combinations other than the above are not available.
2 V
3 LCDV circuit only
4 External power supply only
1 Use of all built-in
D2 Boosting circuit control bit
D1 Voltage regulator circuit (V
D0 LCD driving potential generating circuit (LCDV circuit) control bit
The V
voltage, which makes V
3
power supplies
LCDV circuit only
regulating circuit and
Circuits used
3
voltage is generated from V
OUT
V
3
3
D2 D1 D0 Boosting V
+0.2V, from the V
regulator circuit) control bit
Item
1
0
0
0
OUT
1
1
0
0
. To use the circuit as shown in 2 in the above table, input the
1
1
1
0
circuit
EPSON
“0”
“0”
“0”
“1”
OUT
pin.
C
circuit
regulator
“0”
“0”
“1”
“1”
circuit
LCDV
“0”
“1”
“1”
“1”
“1”
ON
ON
ON
power supply
V
Eternal input
3
MV
, V
V
S1D15714 Series
State
2
1
V
OUT
, V
––
, MV
3
1
, V
2
C
,
OFF
OFF
OFF
“0”
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