A DC power supply takes AC from the wall outlet, converts it to unregulated DC, and reduces the voltage using an input power transformer. typically stepping it down to the voltage required by the load. For safety reasons, the transformer also separates the output power supply from the mains input. In this project, we will design a simple 3A 12V power supply circuit using a 2N3055 power Transistor.


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Hardware Components

You will need the following parts to build this project.

1.Stepdown Transformer (230V/15V)1
2.2N3055 NPN Power Transistor1
3.5A Bridge rectifier1
4.12V Zener Diode1
5.Heat Sink1
6.Resistor (680 ohms)2
7.Electrolytic Capacitors (5000μF, 0.01μF)1,1
9.Connecting Wires1

Circuit Diagram