Variable Power Supply Circuit 3-24V / 2A

Variable Power Supply Circuit 3-24V / 2A  circuit diagram

This the variable power supply with regulated output. The circuit can be altered from 3V to 25V and the electric current is limited to 2 amps as shown. But it's possible to be increased to 3 amps or more by applying a smaller current sense resistor (0.3 ohm).

The power transistor 2N3055 and 2N3053 is used to boost the output current and it should be mounted on suitable heat sinks and the current sense resistor should be rated at 3 watts or more.

About Power Supply
A power supply is a device that supplies electrical energy to one or more electric loads. The term of "power supply" is most commonly applied to devices that convert one form of electrical energy to another, though it may also refer to devices that convert another form of energy (e.g., mechanical, chemical, solar) to electrical energy.
A power supply may be implemented as a discrete, stand-alone device or as an integral device that is hardwired to its load. In the latter case, for example, low voltage DC power supplies are commonly integrated with their loads in devices such as computers and household electronics. More explanation about power supply can be found at

This is the tutorial about "How to build an AC to DC power supply ". The video tutorial covers the basics of diodes, bridge rectifiers, and how to build simple unregulated AC to DC power supplies than can handle a few mA up to several Amps.

Watch the video: