LinkSwitch-XT2 (LNK3696) with opto feedback

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What's the proper circuit if I want to use a LinkSwitch-XT2 with an opto coupler in the feedback loop?

I've the problem, that the LNK3696 blows up at turn on.

첨부 파일Size
Measured Drain-Source Voltage170.56 KB
Schematic25.35 KB

Is the BP/M loop in layout short? IC will blow up if the loop noise is high, which could be caused by long supply current loop to IC BP/M pin. Could you check if this is a possible cause for the blow-up? Make BP/M loop in layout as short as possible.