I am working on a board which is connected to a DC power source of 12V/20A. To control the power to the load , I am using a PMOS as high side switch as shown below :-
My Doubt is, from power dissipation point of view, I should worry about the source or drain of the mosfet?? or Its about the complete package that gets heated. Why I am asking is because I have a bigger pad pin for drain & a smaller one for drain. While routing, I need to provide vias & more copper. I want to understand whether if I only put more Vias @ source pad, can I get away with the heat or do I need vias for drain pad also. Layout is as below :-
If anyone has any suggestion regarding:-
Power dissipation @ 12V/20A through IRF5305, please guide. Datasheet link :- http://www.infineon.com/dgdl/irf5305spbf.pdf?fileId=5546d462533600a4015355e378101995
How to handle the dissipation?