µ PC1934
4. APPLICATION EXAMPLE
4.1 Application Example
Figure 4-1 shows an example circuit for obtaining ±5 V/50 mA from a +3 V power supply.
Figure 4-1 Chopper-Method Step-up/Inverting-Type Switching Regulator
VIN = 3 V
C1 1 µ F
COM
C2 10 µ F
R24
2 kΩ
R28
15 kΩ
R27
5 kΩ
R23
12 kΩ
C21
R26
1 µ F 10 kΩ
CDLY
0.1 µ F
C23
3300 pF
R25
12 kΩ
R29
510 Ω
16 15 14 13 12 11 10 9
VREF DLY IN2 II2 FB2 DTC2 OUT2 VCC
C11
0.1 µ F
µ PC1934
CT
1
CT
100 pF
RT IN1
23
RT
5.1 kΩ
R18
2 kΩ
R18
12 kΩ
R18
12 kΩ
R17
5 kΩ
II1 FB1 DTC1 OUT1 GND
45678
C23
3300 pF
R15
12 kΩ
R16 10 kΩ
C11 1 µ F
R210
470 Ω
R211
24 kΩ
D21
R212
10 Ω
L11
100 µ H
Q23
R111
100 Ω
Q23
Q23
C23
100 pF
R214
10 kΩ
C24
68 µ F
R111
470 Ω
R19
80 Ω
Q13
Q11 R113 10 kΩ
R112 20 Ω
L11
100 µ H
Q12
C113
R111
100 pF
10 Ω
D11
C14
68 µ F
CH2
VO = +5.0 V
R21 IO = 50 mA
47 kΩ
R22
5 kΩ
GND
CH1
VO = −5.0 V
IO = 50 mA
R12
20 kΩ
GND
R11
5.1 kΩ
4.2 List of External Parts
The list below shows the external parts.
Table 4-1 List of External Parts
Symbol
C2
C14
D11
L11
Q11, Q12
Q13
C21
D21
L21
Q21, Q22
Q23
Parameter
Function
10 µ F Input stable capacitor
68 µ F
Output capacitor
Schottkey diode
100 µ H Choke inductor
Buffer transistor
Switching transistor
68 µ F Output capacitor
Schottkey diode
100 µ H Choke inductor
Buffer transistor
Switching transistor
Part number
25SC10M
20SA68M
D1FS4
636FY-101M
µ PA609T
2SB1572
20SA68M
D1FS4
636FY-101M
µ PA609T
2SD2403
Maker
SANYO
SANYO
SHINDENGEN
TOKO
NEC
NEC
SANYO
SHINDENGEN
TOKO
NEC
NEC
Remark
OS-CON, SC series
OS-CON, SA series
D73F series
Transistor array
OS-CON, SA series
D73F series
Transistor array
Remarks 1. The capacitors that are not specified in the above list are multilayer ceramic capacitors.
2. The resistors that are not specified in the above list are 1/4W resistors.
Data Sheet G13567EJ3V0DS00
15