Charger SMPS input faulty

Lisander · Joined: 27 Apr 2006 Posts: 7 Location: Iceland

I got a SWIT battery charger model S-3802S <here> and it doesn't seem to be able to oscillate at all so there isn't any output voltage. I've changed the current control IC (IC1) with no luck. All capacators seem to be ok. This SM looks to be controlled with a opto-coupler from the DC part and I haven't found anything there either.

Any (and many) SMPS hints appreciated. Thanks.

Guest · Posted: Thu Apr 27, 2006 4:43 pm Post subject:

The optocoupler is for voltage regulation. Have you tested the startup resistors?

Lisander · Joined: 27 Apr 2006 Posts: 7 Location: Iceland

Found it

It was one of the two power resistors in the AC circuit (a 3W 75Kohm, out of standard)

Problem solved. Cool