Power Mosfet Switch

[Ssam87]

Hi guys,

I'm back again after your help worked out so well last time giving me an understanding. Now I am required to build a power mosfet switch with changing positions and was hoping for some help / advice on my ideas / results.

The first task is;
Draw a low side pwoer switch using a power mosfet as the switch for driving a 10 amp load.

To which I have drawn this
Attached file

the second task is;
if the switch becomes inductive (20uH) and it takes 200ns to turn off to 0A what will the fly back voltage be present at the transistor? draw a circuit marking flyback voltage and polarity?

This one I am unsure of because in my text I can't find any equations that I can utilize because I have not been given the applied voltage in the first place I only have the inductance rating, time and ona nd off amp ratings? Can anyone shine some equations / light on this query?

regards
Samuel

 

[Ssam87]

okay wooops, i accidentally uploaded the wrong image, that picture is meant for the second part, obviously in the first part the load would not have a diode in parallel with it

 

[MikeMl]

Your questions about current rise time and the action of the snubber diode are partially answered in this thread. Look at the sims