I am looking to convert 12V AC to 12V DC to power an Arduino through the VIN pin. The Arduino will be mounted on a PCB through header pins, please see below.

This is the board I have at the moment.

I am looking to add 2 inputs for AC-12V that is then converted to 12V DC which then in connected to the VIN pin of the Arduino.

enter image description here

The issue I'm having is that I can't find any chips that convert 12VAC to 12DC, the only ones I can find are 80-110 AC to DC.

Is it possible to convert 12V AC to 12V DC safely and could you please advise on the best way to do so?

Would this work as with an GBJ1504 and an 7805

enter image description here

  • \$\begingroup\$ A 7805 won't give you 12V DC, it will give you 5VDC. There are 7812 regulators, but they may require a bit more voltage than the ~15VDC that you get from the bridge. \$\endgroup\$
    – JRE
    Jan 29 at 12:08

You wouldn't normally convert low voltage AC to DC with a chip.

You would normally use a full wave bridge rectifier followed by a smoothing capacitor.

That combination gives you a smooth(ish) DC voltage. Given 12VRMS and assuming 0.7V forward voltage for the diodes, you will get about 15V DC.

You can then use whatever buck converter (or linear regulator) you like to convert the 15VDC to 12VDC.

The simplest solution for most hobbyists is to use a commercial 12V supply. If you have to order parts to make the power supply, you might as well save yourself the hassle of building it and just buy one instead of the parts.

Not to say that building one to learn how they work is a bad idea. It used to be common for hobbyists to build their own power supplies. They weren't as commonly and cheaply available as they are today, so it was common to build a power supply as part of the project itself.

That does, of course, take time away from reaching the actual goal of the project.


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