Power Supply

[prenavin]

Hi there!

While going through my electronics cupboard, I came across a transformer rated at 32volts/ 3.22Amp (105VA). I would like to build a variable power supply with a current limiting feature using this transformer. Unfortunately, all the regulators I came across, has a maximum input voltage of 37 volts. The output voltage of the transformer, after smoothing will be 45.28V (32v x 1.414). Clearly this is not going to work. Could you advise me on possible solutions or circuits??? Also, is pulse width modulation an option to regulate the output voltage?

 

[ScottyUK]

http://www.google.co.uk/search?hl=en&q=hv+linear+regulator&meta=

throws up a few options, both linear and switchmode.



----------------------------------

One day my ship will come in.
But with my luck, I'll be at the airport!

 

[cbarn24050]

Hi, you could try a L296 switching regulator, I've used 1 for a bench power supply. You need to watch the input voltage as the 296 is rated at 46v and your transformer will give more than that off load. A descrete pre regulator, or a series zeneer diode. You will get 4A output but with an external pass transistor you can easily get 15A at 5v from it.

 

[itsmoked]

Linear Technology has about a dozen switchers that take more than that input voltage.