08. APPLIED CIRCUIT EXAMPLES
22
EPSON
S1F76640 Technical Manual (Rev.1.5)
(6) Negative-Voltage Conv Positive-Voltage Conversion
Combining the triple boosting (Fig.8.1) with the negative voltage conversion (Fig.8.11) generates the
circuit shown in Fig.8.14, and outputs 15V and -8.2V from 5V input.
In this case, the output impedance is higher than that for negative voltage conversion only or positive
voltage conversion only.
10
μ
F
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
OSC2
OSC1
V
SS
XP
OFF
TC2
TC1
V
REG
RV
VRI
V
OUT
CAP1
+
CAP1
−
CAP2
−
CAP2
+
CAP3
+
V
DD
C6
10
μ
F
V
OUT
R
OSC
1M
Ω
V
SS
V
DD
＋ －
＋ －
10
μ
F
C1
C2
A
R
L
’
+
−
C3
10
μ
F
C4
10
μ
F
C5
10
μ
F
V
OUT
A
R
L
Io
Io’
+
−
+
−
+
−
Fig.8.14 Negative-Voltage Conv Positive-Voltage Conversion
V
SS
(0V)
V
DD
(+5V)
V
OUT
’ (
−
8.2V)
3
$
V
DD
3
$
V
F
V
OUT
(
+
15V)
3
$
V
DD
Fig.8.15 Diagram of Voltage Relations for Negative-Voltage Conv Positive-Voltage
Conversion
0
5
10
15
0
10
20
30
40
I
O
[mA]
V
O
[V]
Ta=25
°
C
I
O
'=5mA
-10
-5
0
0
10
20
30
40
I
O
' [mA]
V
O
' [V]
Ta=25
°
C
Io=5mA
Fig.8.16 Output Voltage - Output Current Fig.8.17 Output Voltage - Output Current
