adjustable switching power supply

[behranghm]

I am trying to find a scheme for an adjustable switching power supply with the output ranging from 0-30V providing at least 1A current. as I've started to read about different configurations of switching power supplies (buck, buck boost, flyback, half bride, etc) I have become increasingly confused, because designing a switching power supply even at a constant output could turn out to be quite nasty. I don't know which configuration I should be choosing in the end. Can any body guide me what to do? I am fed up with manuals about power supplies, I am looking for some ready to build practical scheme. Or at least something that could turn into a working power supply with some manipulations. Any documentation or links would be nice.

 

[IanP]

Maybe you should consider 30VA (or slightly bigger) step-down transformer and step the mains voltage down to, say, 25-30Vac then normal stuff: fuse, bridge and smoothing cap ..
After that you can use the LM2575ADJ (or similar) switching step-down converter .. Google for it's data sheet with applications ..
https://www.epeec.ethz.ch/pdf/broeck_epe2001.pdf
This converter is adjustable, so the ouptut voltage is between 1.25V and 30, or more ..

The reason I suggested this way is that this circuit will work, and you will be protected against dangerous mains voltages (isolation provided by the step-down transformer) ..

Regards,
IanP