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Power supply? Answered

Since I was thinking of building a bipolar power supply +12V, -12V, using a 12-0-12 transformer and using only diodes and capacitors, which I have successfully built. My problem is how safe can this power supply be? since I am not using any regulators?

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Awesome-aniac (author)2012-01-07

Just use a computer power supply!

http://www.pcguide.com/ref/power/sup/z_mbconatxmain.gif

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VAustin89 (author)Awesome-aniac2012-01-07

How many Amps does a PSU give off, is it just under 1micro amp?

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Awesome-aniac (author)VAustin892012-01-07

No, it supplies around 0.8A at -12 volts.

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Yonatan24 (author)Awesome-aniac2015-11-28

Usually more like 18 AMPS!

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steveastrouk (author)2012-01-07

Not very - there is no current limit, and there is no voltage limit. A capacitor filtered supply is going to show 12 x 1.414 v DC out at low loads too, so your circuits need to withstand nerly 18V potentially.

Steve

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VAustin89 (author)steveastrouk2012-01-07

thank you for the information, well is there any way to create such power supply without the help of a regulator?

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steveastrouk (author)VAustin892012-01-07

You end up making a regulator from discrete parts, like a big fat "series pass" transistor and some other bits.

Unregulated supplies are a royal pain.

Steve

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VAustin89 (author)steveastrouk2012-01-07

Do you have any sample circuits that I can some how use as a basis for this?

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steveastrouk (author)VAustin892012-01-07

Take a look at the Wiki article
http://en.wikipedia.org/wiki/Voltage_regulator
A basic one is illustrated there, towards the end.

Steve

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