MOSFET drivers blowing out
If your load is a transformer, some inductance will be involved. The power leads also have inductance. Switching will create voltage spikes on the main power rail, which can be high enough to blow your driver.

These spikes are normally absorbed by decoupling caps on the power rail, but there is no decoupling on your schematic... and you didn't show your layout.

This is really a hunch. You should show your layout.