This is a high voltage, low current, offline, AC adjustable power supply for electronic/electrical experiments. This power supply is mainly design for switch mode power supply (SMPS) experiments and to drive basic high voltage electrical circuits. Thanks to the isolated step-up transformer this power supply breaks the ground loop and provides shock free – safer high voltage output. This offline (or isolation) feature preventing accidental current from reaching ground through a person's body.

This unit generates 50Hz or 60Hz (selectable at runtime) square wave AC output, and it is capable of generating output voltage between 150V – 290V AC (on no-load state).

Prototype version of offline high voltage AC power supply
Prototype version of offline high voltage AC power supply

As stated above this power supply unit is mainly design for SMPS experiments. This is not work well with linear power supplies because transformers in linear power supplies are get overheating from square wave inputs generated through this unit.

This is a high voltage project. Make sure to insulate all the connections, and install this unit in a "high voltage safe" enclosure. Before applying power make sure to check all your connections and external wirings.

This is an open hardware project. All the project schematics, wiring diagrams and PCB designs are available to download in following location:

Project Related Downloads

Complete schematic and PCB diagrams of Offline High Voltage AC Power Supply


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