continuity between 3.33v and gnd on atx psu?

Im converting my atx into a bench psu. I was checking the continuity between 5v and gnd that i connected to the LTC3780 and i got a beep (one short beep). So i checked the rest of the lines and 5v and 12v also 1 short beep. However on the 3.3v. i get  a long continuous beep.

Is this behaviour to be expected? 

thank you in advance.

If continuity is only indicated briefly, it could be the result of capacitors on the output that initially behave as a short when the test leads are applied.

I would retest each on the ohm setting rather that just a continuity check. If there are capacitors on the output (which is very commonly the case for a power suppply) then you would observe an increasing resistance value, as your ohmmeter charges the capacitors. If there is an internal short, I would expect a low resistance reading to persist.

icey.hood (author)  LargeMouthBass3 months ago

Between gnd and 12v its rising 300+ ohm and 5v is steady at with a slight decrease between 51 and 49 ohms.. and 3v is 36 droping to 19 ohms. would this be a easy fix or shall i just get another atx if possible?


Understanding R C circuits is crucial to working with electronics.

Not really....
Before I started to grow up enough to start work I mostly learned electronics the other way around.
If it did not smoke it meant I made progress LOL