I am attempting to make a PCB that high-side switches an inductive load (water pump) that draws 4.6A peak. The switching scheme will not include any PWM, just basic on/off functionality.
My concern is clamping the voltage spikes from the load during turn-off. I want to avoid going into avalanche mode on the MOSFET to ensure maximum reliability as the board will be operating in temperatures of 80-90 C ambient.
My current circuit idea is shown below:
D2 will conduct below the maximum Vds of the MOSFET, during switch off of the load where the source voltage will go negative.
I am less confident in the behavior of D1. My intention with D1 is to conduct during shut off of the load, so that Vgs does not exceed the maximum allowable. My uncertainty stems from the gate driver - how will it behave in this scenario?