M5291P/FP
5. Inverse Polarity Circuit
VIN = 5 V
VOUT = −5 V
IO = 40 mA
f = 50 kHz
1
L
2
260 µH
3
CT
820 pF
D
4
VOUT
−5 V/40 mA
+
COUT
100 µF
8
QS
R
7
Oscillator
Comparator
6
1.17 V
+
−
5
R1
1 kΩ
RSC
1.5 Ω
+
VIN
5V
CIN
100 µF
R2
3.3 kΩ
6. Inverse Polarity Circuit with Transistor
VIN = 5 V
VOUT = −12 V
IO = 1 A
f = 50 kHz
PNP
Tr
R3
100 Ω
1
R4
24 Ω
L 20 µH
2
3
CT
820 pF
D
4
VOUT
−12 V/1 A
+ COUT
220 µF
QS
R
Oscillator
1.17 V
Comparator
+
−
8
7
RSC
0.1 Ω
6
+
VIN
5V
CIN
100 µF
5
R1
2.4 kΩ
R2
22 kΩ
REJ03D0841-0300 Rev.3.00 Jun 15, 2007
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