Diode? Identification

I have a board with 3 burnt diodes (the board labels theM as D3/D9/D11). The logo is General Semiconductors Industries Inc which is now Vishay. The printing is BFK 66A. If I can find the datasheet I can find a newer part, but I can’t find anything for specifically this diode.

Hello Testsubj and welcome to the Digikey TechForum,

Based on the information you provided I was able to find the Vishay datasheet linked here that mentions the BFK marking. The marking is listed as being Vishay SMCJ30A, I have linked what we have available from that part number.


Since SMCJ30A are transient suppressor diodes, the circuit should work when they are removed.

If the circuit doesn’t work with them removed, then there are more components that were damaged by the surges that you’ll need to locate and replace.

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Y’all kick butt. Thank you both!