S6B0755 Datasheet, PDF (29/68 Pages) Samsung semiconductor – 128 SEG / 65 COM DRIVER & CONTROLLER FOR STN LCD

128 SEG / 65 COM DRIVER & CONTROLLER FOR STN LCD
PRELIMINARY SPEC. VER. 1.0
S6B0755
Voltage Converter Circuits
These circuits boost up the electric potential between VCI and Vss to 3, 4, 5 or 6 times toward positive side and
boosted voltage is outputted from VOUT pin. It is possible to select the lower boosting level in any boosting circuit
by “Set DC-DC Step-up” instruction. When the higher level is selected by instruction, VOUT voltage is not valid.
[C1 = 1.0 to 4.7 µF]
Vss
VOUT
- _C1
+
Vss
VOUT
- _C1
+
C3+
C1-
VOUT = 3 x VCI
- _C1
C1+
+
C2+
C2 -
C4+
+ _C1 VCI
-
-
Vss
Figure 17. Three Times Boosting Circuit
C3+
C1-
C1+
C2+
C2 -
C4+
VOUT = 4 x VCI
+ _C1
-
-
- _C1
+
+ _C1 VCI
-
-
Vss
Figure 18. Four Times Boosting Circuit
Vss
VOUT
- _C1
+
VOUT = 5 x VCI
C3+
C1-
C1+
C2+
C2 -
C4+
+ _C1
-
-
- _C1
+
+ _C1
-
-
- _C1
+
VCI
Vss
Figure 19. Five Times Boosting Circuit
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