Buck Converter Overshoot problem

[KlausST]

Hi,

My recommendations
* move as much as possible traces to the red layer (except GND). = make GND layer as solid as possible.
* shorten the unnecessary wiring from C9 to R5
* if R5 is low ohmic then use kelvin wiring (= extra sense traces directly from the resistor pads)
* move the SMD components to the red layer side
* if Q2 is a Mosfet install a GS-resistor.

Klaus

 

[Easy peasy]

C6 is not bad, output caps, the smaller one should be right by the L ...

--- Updated Nov 9, 2020 ---

a snubber across mosfet would be helpful too - snubbers need very tight layout though ( not like the one on the diode )