
Data Sheet S13368EJ3V0DS00
20
μ
PD16682
9. COMMON OUTPUT STATUS SELECT CIRCUIT
With the
μ
PD16682, the common output status select command can be used to set the scan direction for COM
outputs (see Table 9
1). As a result, there are fewer IC layout constraints when setting up the LCD module.
Table 9
1. Setting of Scan Direction for COM Outputs
Status
COM Scan Direction
Normal (forward)
COM
0
→
COM
63
Inverted (reverse)
COM
63
→
COM
0
10. POWER SUPPLY CIRCUIT
10.1 Power Supply Circuit
The power supply circuit, which supplies the voltage needed to drive the LCD, includes a booster circuit, voltage
regulator circuit, and voltage follower circuit.
The power control set command is used to control the ON/OFF status of the power supply circuit’s booster circuit,
voltage regulator circuit (V regulator circuit), and voltage follower circuit (V/F circuit). This makes it possible to jointly
use an external power supply along with certain functions of the on-chip power supply. Table 10
1 shows the
function that controls the 3-bit data in the power control set command and Table 10
2 shows a reference chart of
combinations.
Table 10
1. Control Values Set to Bits in Power Control Set Command
Item
Status
H
L
D
2
Booster circuit control bit
ON
OFF
D
1
Voltage regulator circuit control bit
ON
OFF
D
0
Voltage follower circuit control bit
ON
OFF
Table 10
2. Reference Chart of Combinations
Use Status
D
2
D
1
D
0
Booster
Circuit
V Regulator
Circuit
V/F Circuit
External Power
Supply Input
Booster-
related Pin
<1> Use on-chip power
supply
H
H
H
{
{
{
V
DD2
Used
<2> Use V regulator
circuit and V/F circuit
only
L
H
H
×
{
{
V
LCD
Open
<3> Use V/F circuit only
L
L
H
×
×
{
V
LC1
Open
<4> Use External power
supply only
Remarks 1.
The booster-related pins are indicated as pins C
1+
, C
1–
, C
2+
, C
2–
, C
3+
, and C
3–
.
2.
Although combinations other than those shown above are possible, they have no practical uses and
L
L
L
×
×
×
V
LC1
to V
LC5
Open
therefore cannot be recommended.