Epson S1F70000 Power Supply User Manual


 
S1F76540 Series
2–36 EPSON S1F70000 Series
Technical Manual
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
F) of diodes can reduce the booster output voltage. As the example
of Figure 2.14 uses three diodes, the drop of “V
F” voltage multiplied by three occurs. The booster output
voltage is expressed by equation (5).
To increase the |V
O'| value, use the diodes having a smaller VF.
| V
O' | = 3 × | VI | – (3 × VF) • • • • Equation (6)
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
I pin.
Wiring Example When Changing the
Regulator Temperature Coefficient
The temperature coefficient of the regulator depends on
the temperature coefficient of the internal reference
Figure 2.16 Wiring example when changing the regulator temperature coefficient
V
REG
C
O
C
REG
RP
RT
V
DD
V
I
C
I
R1 R2
C2
C3
C1
+
+
+
+
+
+
V
O
V
RI
V
REG
RV
V
DD
FC
TC1
TC2
C2P
C2N
C3N
C1N
C1P
V
I
P
OFF1
P
OFF2
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
voltage. To set another temperature coefficient, use a
thermistor resistor or others as shown in Figure 2.16.