Simple Variable Power Supply DIY Circuit Diagram

Introduction

A variable power supply is one of the essential tools in electronics. It can supply a range of voltages and currents for various electronic devices. This adjustable power supply can be built using few components. In this article, we will talk about a very simple variable power supply using a 2N3055 transistor, a 5k potentiometer, and one 2.2 ohm resistor.

The 2N3055 transistor is a popular high-power transistor with a maximum voltage rating of 60V and a current rating of 15A. The 5k potentiometer is used to vary the output voltage, and the 2.2 ohm resistor is used for current limiting.

Components List of Simple Variable Power Supply

2N3055 Transistor x 1
5k Potentiometer x 1
2.2 ohm Resister x 1
2-Pole Terminal Block x 2 (optional)
Heatsink for transistor
12-30 volt external Power Supply

Circuit Diagram of Simple Variable Power Supply

**Simple Variable Power Supply Circuit Diagram**

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Construction of Simple Power Supply

The construction of this Simple Variable Power Supply is easy and requires minimal effort. The first step is to assemble the components in the circuit board. The 2N3055 transistor serves as the power amplifier, and the 5k potentiometer controls the output voltage.

Connect one end of the 2.2 ohm resistor to the ground pin of the potentiometer and connect the other end to the ground of the output. The base of the transistor is connected to the wiper of the 5k potentiometer. The emitter of the transistor is connected to the positive terminal of the output.

The output voltage can be varied by adjusting the 5k potentiometer. As the potentiometer is rotated, the voltage across the base-emitter junction of the transistor varies, changing the collector-emitter voltage and hence varying the output voltage.

Conclusion

In conclusion, this simple adjustable power supply using a 2N3055 transistor is an easy to build and cheap solution for electronic hobbyists. This power supply can be used for various applications that require different voltage and current levels. However, it is essential to be cautious when working with electronics and follow safety procedures to avoid any accidents.