How to rate current from SMPS??

Zero Cool

Paid Member
2004-09-20 6:10 am
At a garage sale the other day i picked up a couple of broken soundstream car amps for a couple bucks. The smaller amp an SA-80 has a separate SMPS power supply board inside which i found very interesting as I had hoped to use just the power supply parts anyway for a LM3886 based car amp project. this board looks like it would work perfect and the voltage is about right.

it is based on a SG3524 IC with a pair of BUZ11 mosfets driving a toroid transformer, feeding to TO-220 type dual high speed diodes and 1000uf per rail. I see that the board is short stuffed and that 2 additional pairs of mosfets could be added and 4 more capacitors. a very simple design.

I am curious if i can figure how what the rated current is for this power supply? is there a method to tell? or should i just load it down and see if/where it breaks or otherwise sags past some point? I see that the SG3524 has some current limiting protection inside. maybe the supply will just shut down?? I am looking for schematics now.