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Which Components to use? Answered

I want to make a circuit that is powered by 220v ac. It consists of a cooling fan that requires 12v, 0.7a, a  PCB with 10 LEDs in parallel that requires 0.25a, 3.5v and a single led that requires 3.5v,0.025a. I know how to calculate resistor values but it would be better if you give the values. I want to know which diodes should I use to make the rectifier and should I use a capacitor? In short, I want to know  how to set up this circuit, what components to use and their value and power ratings.



Best Answer 4 years ago

OK here are discreet components.


thank you! Can you please point out the 1,2 and 3 pin of LM 317(are they positive?) in the diagram? And also is the 470uf capacitor ceramic?

Yes, but in your list of components you don#t include the transformer.

If you can make an isolating PSU that fits in less space than one you buy that's built on a mains plug, then you've won.

your average computer power supply should power it salvage one and use it.

At your stage of understand PLEASE BUY a suitable power supply, It isn't going to cost a lot and will be very useful in the future.