LNK403-407 my problem

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    Dear PI Experts.
I made 4 LED drivers for 185-265 VAC :
- 6 W as DER-277 (LNK403)  without AC Dimming circuit ;
-12 W as DER-284 (with LNK404 );
-16 W as DER-284 (with LNK407);
-24 W  as DER-286 (with LNK407)  without Surge Supression Circuit.
All calculeted in PIXIs Designer 8 with recommendation AN-49.
All works:  - current stabilization good ; -efficiency and PFC good ;
- OVP worked ;  -  output  short-circuit protection worked.
But in all this drivers I have the same problem:
-peaks in input AC current ( on serial resistor 1 Ohm )
 -  oscillogram  "Input AC current.bmp" ;
- drop-outs in output voltage( secondary wind - on Anode output diode)
 - oscillogram  "V on Anode output diode.bmp".
Please , help me - what is the reasons this droop-outs of working-cycles  LNK-IC.
 Regards.
valera-1234

I don't see any attachment. Please re-upload. Please measure the drain voltage and current as well if you can also the peak you observed in input AC current. Make sure the transformer is not saturating which may cause such peak.