Introduction:
Having a reliable power source that can provide variable voltage and current is very important in the field of electronics. A variable power supply enables an electronic engineer to work on different circuits and components that require different voltages and currents. In this article, we will discuss the design of a variable power supply 0-30V_10A using dual 2N3055 transistors, LM317, BD139, A/V meter and two potentiometers to control amps and volts.
Components Required:
Following is the list of all components used in this project:
- 2N3055 Transistor x 2
- LM317 Regulator IC x 1
- BD139 Transistor x 1
- 7805 Regulator IC x 1
- 0.1uf (104J) Capacitor x 3
- 0.33 Ohms / 5 Watts Resister x 2
- 1k Resister x 1
- 220 Ohms Resister x 1
- 10k Potentiometer x 1 with knob
- 5k Potentiometer x 1 with knob
- 0-30 Volts Digital A/V Meter x 1
- 12 Volts On/Off Switch x 1
- LED x 1
- 4mm Banana Connector Socket x 1 Pair
- 12v-0v-12v 5 to 10A Transformer – (As required)
- 6-10A Bridge Rectifier
- 6800uf / 50v Capacitor
- 104J / 0.01uf Capacitor
2N3055 Pinout
LM317 Pinout
Explanation:
Two potentiometers are used to control the output voltage and current. These potentiometers divide the voltage and current respectively, and adjust the output based on the user's settings. BD139 transistor helps in protecting the circuit from short circuit and overload.
The A/V meter displays output voltage and current, making it easy for the user to monitor the performance of the power supply. It also helps protect the circuit from damage caused by overload.
Use:
Using a variable/programmable power supply allows digital or analog control of the power supply output by a control system for maximum versatility