I built a LED driver with PT4115 IC. The board lighted LEDs up but sparks appeared around SW, VIN & GND pins after 10 seconds and the phenomenon didn't damage the IC. I recorded it by my mobile phone.
I removed R2, D2 and R3 so the DIM pin is floating. It should help us to concerntrate to this problem.
I checked every pin of the IC and didn't find any short or something wrong. I thought that something conductive around these pins and start to conduct after 10 seconds. It is very strange and confused me.
Any good suggestion?