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High current fixed voltage

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Hello all

I would like some help in building a fixed voltage.

I have 12vac 12A which I would like to make them 12VDC Fixed
and 5vac 5A which would like to make them 5VDC Fixed.

I know I have to pass them firstly from a bridge ... I bought one which can go up to 25A so now you can say that I have 12V Pulsating DC and 5V Pulsating DC. What can I do to make the 12v / 5v DC and make use of the 12A and 5A because a 7812 and 7805 only handles 1A.


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The first thing you should do is determine the exact amount of current you will need. Use a transistor with double this current. Make a regulator with feedback. This involves a reasonable amount of circuit design. I would use a low current transistor whose emitter goes to the base of the high current transistor and whose collector shares the same input voltage. This is a darlington arrangement which allows a small current change to control the large current of the high current transistor. The input to the low current transistor is the control. You could use a transistor whose collector goes to the control and shares the same input voltage but with resistors so that that it's collector voltage will be able to change. Do you understand so far?

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