HD66717 Datasheet, PDF (55/90 Pages) Hitachi Semiconductor – (Low-Power Dot-Matrix Liquid Crystal Display Controller/Driver)

HD66717
The HD66717’s internal operational amplifiers have a reduced drive current to save current consumption;
when the internal operational amplifiers cannot fully drive the LCD panel used, an appropriate capacitors
must be inserted between each output of V1OUT to V5OUT and V_CC to stabilize the operational amplifier
output (Figure 33). Especially, the capacitors for V1OUT and V4OUT must be inserted when 1/26 duty
or 1/34 duty drives.
OPOFF = GND
0.1 µF to 0.5 µF*
V_CC
+ +++ +
V_CC
R
HD66717
V_CC
V1OUT
+
–
V1
V2 ^R
V2OUT
R
V3 ^R
V3OUT
R
V4OUT
+
–
V2
LCD
multiplexing
driver
+
–
V3
+
–
V4
R
V5OUT
+
–
V5
VR
V_EE
Vci
C1
0.47 µF
to 1 µF ₊ C2
V5OUT2
Booster
+ ^{0.47 µF}
to 1 µF
GND
V5OUT3
SEG1–SEG60
COM1–COM32
COMS1–COMS2
+ ^{0.47 µF}
to 1 µF
GND
Note : The capacitors for V1OUT and V4OUT must be inserted when 1/26 duty or 1/34 duty drives.
Figure 33 Operational Amplifier Output Stabilization Circuit Example
507