I have what I believe to be a diode I need help Identifying. It looks like it has a FairChild F on it, the part marking is “AD21 GFM.” There are also others with markings “AD33 GFM” that have similar arrangements and dimensions. It has two pins that wrap down and around the body. One side seems as if they’re connected to a switch, and the other to ground and parallel to a capacitor then to a wiring harness. The dimensions are approx 6mm x 7mm x 2mm. They’re reading like an open circuit when measuring resistance and voltage drop.
Hello,
I was not able to locate a match yet. We are working on this and should be back in touch soon
Thank you
Ryan
The F logo is Fairchild (onsemiconductor)
GFM with no polarity mark associates with bidirectional
SMCJ33CA
I don’t think Fairchild makes these anymore but they’re a common TVS diode, here is an example of the same type of part from another manufacturer:
SMCJ33CA
But before you remove these diodes you may want to question your testing methods now that you know this is a 33V Zener TVS Diode.
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