Hello!,
Can somebody tell me what I'm doing wrong whit my prototype circuit??, LM5017 gets burned as soon the UVLO voltage is reached (Around 67V). I burned my 5 samples trying to make it work. I tried changing the 220uH,1A Isat inductance by 47uH,1.6A, I tried removing D2 just in case a peak current flows into C22 at start up, but I still have the same problem. As far I reviewed, I meet all the requirements in the datasheet, including the 1.2uF capacitor at voltage input, since the output current is not going to be more than 40mA. I attach the schematic and layout so maybe somebody tell me if I missing something. In the board I just loaded the Buck converter, and the ground plane is in the area with no traces. The only way to make t work is removing R21 so the UVLO is disabled and it start working at soon enough voltage is available to make the device work.