Offline 230VAC Flyback SMPS with TO220 FET and legs not bent..Too close to each other

[Easy peasy]

Certainly sharp edges don't help - like the steps on the leads on the TO-247 ...

 

[marce]

Thanks, though i am speaking of a TO220 FET soldered into a PCB with straight legs. The actual soldered pads , as you know, do not have solder resist over them...There is solder resist between the PTH pads on the PCB, but i dont think that makes it category B4...to get category B4, we would have to spray a insulative coating over the pads, and we have not done this, but as Betwixt says, the D and S are close together n and inside the TO220 body anyway.

Read the specification you put a link up to properly, ie do your homework before coming back with an incorrect supposition, read section 6-3-4 it explains it all, now we have used this spec for military and aerospace and have had everything passed in the past.

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