220VAC to 5VDC transformator?

Fair enough.

The steps I would take are:

  • Bridge Rectifier
  • Storage capacitor for between peaks storage.
    I would calculate the smallest capacitor that would function then add 50%
    The equation for the discharge droop in post #16 is approximately:
    I = C dv/dt I = amps, c = farads V = volts and t = seconds.
    I = your max output current divided by the converter efficiency.

Here the goal is to keep the period over which the capacitor charges as large as you can get. But keep the minimum well above the voltage the buck can regulate out.

The rectifiers should be 2x the required current capacity. You can estimate the current by estimating the charging time as a % of the full 1/2 cycle and figure what the current would need to be to charge the capacitor and supply the load.

The above are practical suggestions, they are not the exact same results one would get if a program like NSpice were used.

Do not worry about my life and my house. I take care of that. If you are against my method to do circuits, it's better to not post anything.

As I said before, many questions are asked by (young?) folks who don't realize the danger of dealing with mains or don't know other options exist for some endeavor.
You will find the folks here help with questions, offer opinions (guidance?) and comment on the stated approach. That's what we do. Many of us have extensive knowledge of electronics in general and wish to use that knowledge to help others, rather that letting it go to "waste".

There are not check boxes when asking questions, you get what you get. It often depends on how a question if phrased and who is logged in and decides to answer. I guess the responses if the forum equivalent of "pot luck". Its been that way for many years and I expect it will never change. It is your responsibility to take the info provided and decide what to do with it.

And in the same line, if you are going to build do learn, it might be wise to put a fuse between your transformer and your diodes as well. If you have short-circuit it is better to blow up the fuse than to start a fire with the diodes and the rest. The low voltage part is not dangerous for electrocution (if used with a insulating transformer) but the thermal power it can release can be considerable.
What also can be of interest is a bridge rectifier instead of the diodes, these things are built and designed to be part of a power supply and many of them fit a cooling plate quite easily.

I think you need to work on your attitude and stop giving those who are trying to help you a hard time and sarcastic answers.
There are multiple ways of learning without risking life and limb.
Opening up to good suggestive advice would be a good start.


I have been grateful for many answers here, but I will not highlight those who advise me to buy a mobile charger when I ask specifically about how to best make a power supply.

Btw. It`s many good answers that i have not read properly jet, so thank you wery mutch :slight_smile:

Bit i will not participate more in this thread. Too much discussions of unnecessary things.

But thanks to all that have tried to help me :slight_smile:

Hang on!

If you asked how to best make a power supply then I specifically gave you the answer!

If you want to puddle around making things just for the educational benefit, that's perfectly fine, we don't object to that. Just don't confuse it with good engineering. :face_with_raised_eyebrow:

You can halve the number of diodes by using a center tapped transformer.