Adjustable Power Supply 3-30V/2.5A

This is an adjustable power supply circuit, also known as variable power supply. . You may use this circuit for general purpose usage.

Here the schematic diagram:

Component list:

R1 = 560R 1/4W	C1 = 100nF
R2 = 1,2 K 1/4W	C2 = 2200uF 35-40V
R3 = 3,9 K 1/4W	C3 = 100 pF
R4 = 15K 1/4W	C4 = 100uF/ 35V
R5 = 0,15R 5W

D = B40 C3300/2200, 3A rectifier bridge
P1 = 10K potesiometer	TR1 = BD 135
IC = LM723	TR2 = 2N3055

Bottom PCB layout:

Adjustable Power Supply 3-30V/2.5A pcb layout

Top PCB layout (Components placement):

For complete explanation, circuit's works and how to build this circuit into the box, download the full tutorial here

Comments

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Power Supply Adapter

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