Epson Power Supply IC S1F70000 Technical Manual page 79

S1F76540 Series
Output voltages
• When diodes are used for voltage boosting, the characteristics of diodes directly affect on the voltage boosting
characteristics. The forward voltage drop (V
of Figure 2.14 uses three diodes, the drop of "V
voltage is expressed by equation (5).
To increase the |V
O
| V ' | = 3 | V
O
Notes
1 Input and output current conditions
To satisfy the input and output current ratings, take care to limit the input current below the ratings.
2 Input and output voltage conditions
During forward voltage conversion, the input voltage ratings are the same as two-time negative voltage boost-
ing (see Table 2.3).
Application in other setup conditions
When used in the High Output mode, connect the FC pin to the V
Wiring Example When Changing the
Regulator Temperature Coefficient
The temperature coefficient of the regulator depends on
the temperature coefficient of the internal reference
V
REG
V
DD
V
I
Figure 2.16 Wiring example when changing the regulator temperature coefficient
2–36
'| value, use the diodes having a smaller V
| – (3 V )
I F
C
O
+
C
REG
+
R1 R2
+
C
I
) of diodes can reduce the booster output voltage. As the example
F
" voltage multiplied by three occurs. The booster output
F
.
F
pin.
I
voltage. To set another temperature coefficient, use a
thermistor resistor or others as shown in Figure 2.16.
1
V
O
RP
2
V
RI
RT
3
V
REG
4
RV
5
V
DD
6
FC
7
TC1
8
TC2
EPSON
• • • • Equation (6)
+
C2P 16
C2N 15
C2
C3N 14
C3
C1
C1N 13
+
+
C1P 12
V 11
I
P 10
OFF1
P 9
OFF2
S1F70000 Series
Technical Manual