13.8 Volt 20 A Transformerless Power Supply

Do you need high current power supply without heavy and expensive transformer? Then, this circuit would be great choice for you.

This 13.8 Volt 20 A regulated transformerless power supply. 20A transformer is very-very expensive, large in size and very heavy in weight.

This power supply capable in delivers around 20Amps at 13.8V. For lower currents, a separate current limiting output, capable of 15ma up to a total of 20A has been added. Let us see what we have got here. The power transformer should be capable to deliver at least 25A at 17.5 to 20V. The lower the voltage, the lower power dissipation. The rectified current will be ironed by the C1, whose capacity should not be less than 40.000uF, (a golden rule of around 2000uF/A), but we recommend up to 50.000uF. This capacity can be built up by several smaller capacitors in parallel. The base of this design is a simple 12V regulator IC 7812.

More explanation about this circuit, please visit this page

circuit diagram

View Comments

Recent Posts

Guitar Synthesizer Schematic Diagram Collection

Guitar Synthesizer Schematic Diagram In this post, we provide a collection of schematic diagrams of…

55 years ago

Handy Talky HT DIY Schematic Diagram

Handy Talky Schematic Diagram This is an old electronic scheme of the Handy Talky (HT)…

55 years ago

Doorbell Ringer Birdie Tone

This is an old or "very old" schematic diagram of birdie tone or sound generator.…

55 years ago

200W MOSFET Amplifier based IRFP250N

Here is the 200W MOSFET amplifier powered based on four piece of IRFP250N, they are…

55 years ago

300W RMS Stereo Power Amplifier based IC TDA7294

This is the 300W RMS stereo power amplifier circuit project. This amplifier is based four…

55 years ago

Stereo Tone Control with Line In + Microphone Mixer

This is an active stereo tone control circuit using very well known op-amp IC of…

55 years ago