Hello my friends.
Please help me.
I used lm5161 to design a converter with input (15v-75v), output is 12V. After I assembled with my PCB, then I tested it. the sparks appeared among PIN 1,2 and PIN 3,4. After 30 second, LM5161 burned.
I used 24VDC for input power. I tried 2 times with 2 PCB, but the result was the same. I sure that I have soldered the thermal pad using the hot air gun. I asked ST supporter by chat, they told to me as my schematic is correct. So, I dont know the reason for my problem.
I inserted my schematic, PCB in this post. Please find the cause for me. Thank you so much.