1.5V-25V DC Variable Power Supply

This is 1.5V-25V DC Variable Power Supply. The power supply use KR142EN14 or LM317 as regulator component. KR142EN14 or LM317 is capable to handle electric current up to 2A. You may use LT1083/84/85 to handle electric current of 7A/5A/3A. Resistor R9 is used as a current sensor to an ammeter.

Components list:

R1 : 4K3
R2 : 18K
R3 : 100
R4,R8 : 100K
R5 : 1K
R6 : 240
R7 : 4K7 ( Variable resistor )
R9 : 0.33 E
C2 : 0.1uF
C3 : 10000uF/40V

C4 : 100uF/25V
D1 : KY202
D2 : KD521
D3 : D311
D4 : KC147
T1 : KT814B
T3 : KT209
T4 : KT3102
IC1 : KR142EN14 (LM317)

Circuit source: 1.5V-25V power supply with preregulator

Comments

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Power Supply Adapter

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