Epson, Positive voltage conversion – Epson Power Supply S1F70000 User Manual
Page 78
S1F76540 Series
S1F70000 Series
EPSON
2–35
Technical Manual
S1F76540
Series
Positive Voltage Conversion
The S1F76540 can also boost up a voltage to the posi-
tive potential using external diodes. In such case, how-
ever, the regulator function is unavailable. Figure 2.14
gives a wiring example for three-time positive boosting,
and Figure 2.15 provides its electrical potential rela-
tionship.
Figure 2.14 Wiring example of positive voltage conversion (3-time boosting)
◊
Setup conditions of Figure 2.14
• Internal clock : ON (Low Output mode)
• Booster circuit : ON
• Regulator
: OFF
◊
Power-off procedure
• Set the P
OFF2
pin to low (V
I
) to turn off all circuits.
◊
Two-time boosting
• To boost up a voltage two times, remove capacitor C1 and diode D1 of Figure 2.14, and connect the anode of
diode D2 to the V
DD
pin.
V
DD
V
O
V
RI
V
REG
RV
V
DD
FC
TC1
TC2
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
C2P
C2N
C3N
C1N
C1P
V
I
P
OFF1
P
OFF2
D1
V
I
C
I
+
C1
+
C2
C
O
V
O
'
+
+
D2
D3
V
DD
V
I
V
I
3V
I
3V
I
– (3
∗
V
F
)
3
∗
V
F
V
O'
Figure 2.15 Potential relationship during positive voltage conversion (3-time boosting)