LT8606 maximum rating versus recommended operating voltage range

As the maximum rating is 42V, there is probably no additional margin. That is the meaning of absolute maximum rating.
For line transients you have to use a TVS diode. But beware of clamp voltage at the clamp current - which depends on your supply. Or use a surge stopper- / hot-swap-circuit in front of your converter

Thanks, Alexxx. I'm aware that the absolute maximum rating shall not be exceeded in any case. But how can a datasheet be established with input voltage range upto 42V? This does not fit together.

Hi AN,

The 42V input should include the DC and the switching caused high frequency ringing. So the max VIN is highly layout related.

The standard demo board has almost no ringing at high VIN condition so the VIN can go up to around 40V. We suggest to copy our standard demo board layout for the best performance.