Chopper Regulators
Fig. 9 Threshold Voltage vs. Junction
Temperature
1
0.9
0.8
VTHL
0.7
0.6
0.5
0.4
0.3
VTH(ON)
0.2
0.1
0
–25 0 25 50 75 100 125 150
Junction temperature Tj (˚C)
s Step - Up Type Circuit Diagram (12V Output)
L
90µH
D
IO VO12V
CIN
+100µF
2 1 R2
8.56kΩ
+
VIN
4
5
5V
1kΩ
0.47µF
3
R1
1kΩ
CO
470µF
ON/OFF control
s Flyback Method Circuit Diagram
D
IO VO
CIN
100µF
+
2
1
R2
+
VIN
4
5
1kΩ
0.47µF
3
R1
1kΩ
CO
470µF
PQ2CF1