Why is only the first turn in the coil hotter compared to other two turns?
In this, only the turns of the top part seem to be hotter compared to the bottom.
Current through the coils is 2 A. It is connected to a half-bridge operating in buck mode at 1 MHz.
I don't know if I am making any mistakes in capturing the images, but I expected a more uniform distribution of the heat.
Here are some details about the second coil:
and Coil connected to the board
The board is FR4 material and turns are copper.