Trying to identify a diode

Thread Starter


Joined Jun 25, 2023
I have a surface mount diode with a low resistance short in an unlabeled location on the back side of a TDK-Lambda ZWS150BAF-12 12V 12.8A power supply board. The diode connects anode side to the center or "D" lead of Q3, a TO-220 Mosfet and the cathode goes to the + side of the 420V 60uf high voltage filter capacitors (2 connected in parallel) The diode is black rectangular shape and it's labeled V658: (The V6 are on the top line and the 58: are below it. ) I've attached a picture of that diode on a good working board, the easiest one to read that I could find. I've removed the diode in question from the bad board and the 3.5 ohm short stays with the diode so its definitely the problem. I haven't had any luck trying to research it online so I'm hoping someone here might be able to help me identify it so I can order the right one to replace it with. I've also attached a few pictures of the complete board top and bottom side and the part number sticker. I've already asked the manufacturer and they won't disclose that information due to liability reasons. Any help would be greatly appreciated. Thanks!



Joined Feb 16, 2022