Re: Power Supply Design

Brian wrote: 
Hello, I have a need of a 300-350VDC Power Supply. I was wondering what
the cheapest design solution would be.  The power supply will be used
to charge large capacitors.  (I am tired of using a hacked disposable
camera circuit board which takes forever to charge up the caps.)
Winding my own transformer is possible although I dont look forward to
1000s of turns if thats what it will involve.

Thanks,
Brian


Hi, Brian -

It can be done with 4 diodes and 2 capacitors (and and electrical outlet) where the output capacitor is the one you want to charge. Look up voltage doubler. It will double the peak line voltage (to about 330VDC).

You will need to use adequate capacitors and diodes. Also, you will need to protect the circuit from inrush with a resistor.

Take note that there is no isolation from the mains. If you are charging an isolated capacitor and then removing it from the charger, this should not be a problem (other than possibly electrocuting yourself).

Good luck.

John
.

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