How to build Fixed Voltage Power Supply

The fixed voltage power supply is useful in applications where an adjustable output is not required. This supply is simple, but very flexable as the voltage it outputs is dependant only on the regulator and transformer you choose. The maximum output current is 1.5A.

Circuit diagram

C1 2200uF 35V Electrolytic Capacitor
C2, C4 0.1uF Ceramic Disc Capacitor
C3 10uF 35V Electrolytic Capacitor
D1, D2 1N4007 Silicon Diode
BR1 2A 30V Bridge Rectifier
U1 Regulator (See Notes)
T1 Transformer (See Notes)
S1 SPST 2 Amp Switch
F1 2A 250V Fuse and Holder
MISC Heatsink For U1, Line Cord, Case, Wire

1. Since this project operates from 120 (or 220, or 240, etc.) volts AC, it MUST be built inside a case.
2. U1 will require a heatsink.
3. You will need to choose T1 and U1 to match the voltage you want. Use the table below as a reference.

Output Voltage, T1, U1
5V - 6V, 1.5A - 7805
6V - 6V, 1.5A - 7806
9V - 12V, 1.5A - 7809
12V - 12V, 1.5A - 7812
15V - 24V, 1.5A - 7815
18V - 24V, 1.5A - 7818


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