How to convert a 110v input psu to a universal psu

Thread Starter


Joined Apr 2, 2020
Dear all
I have a small project in which I would like to convert a 110v ac input psu to a universal psu that can work with both 240v and 110v.

I know just basic electrical physics which I studied in high school. Hence I need basic guidelines

thanks in advance for your support

please see attached pictures of the bottom and top view of the psu. I can post the components data.



Joined Jun 5, 2013
Pretty much only by replacing the transformer.

It appears to be a single output linear supply. Do you know the specs? Replacing the whole board with a switcher that is rated for 110 to 240 (or wider) would do the trick. Just remove the board and run the output of the switcher where it's output goes.



Joined Mar 19, 2019
By the time you do that, just on the price of parts alone, it will be cheaper to buy a new one that has a 120/240 input switch. ~$55 USD for switch mode, ~$85 USD linear including shipping for US.

Edit: Why do you want dual voltage input? The reason I ask is you will have to pay more for the transformer than for single voltage input one. Single voltage input can drop the prices I quoted by ~ a third.
Last edited:


Joined Mar 10, 2019
Not only the transformer, but the capacitor is rated only 200V, you need at least 400V. Things like the MOV at the input, fuse ratings, filter capacitor, bridge rectifier, etc. all have to be changed. Need to change a lot of that design to make it "universal". I just don't think it is feasible with the one you have.