I think that the shunt resistor is just a waste of energy
negative charged electrons move toward the positive
Thanks for the reply.My understanding is that the MOSFET has to go on the positive side, to avoid leaving the electronics "hot". That's why I was considering a P channel. At home I have some IRF540, that are N-channel power MOSFETs.
@ fungus And your power loss is more with the P channel then the N channel.
@ what fungus said your power loss is more with the P channel then the N channel.