Yeah low on Rds is vital this is why most people use N channel fets...as well as common and cheap
However, over that last few years some interesting P channel low on rds fets have become available. Specifically as these have the Ishutdown sense. Meant to say IRF also has application notes,
AN-1118 or A
N-1058 and design tip DT99-4/5/6 for this
family of fets.
Since on rds is a function of current passed but I found 12V @4A absolutely no problem for the IR3315, doesn't get warm at all. While these are low on rds there are no small packages for this family. You might get some P channel low on rds capable for the current drain in the SO8 packages though, but you lose the intelligent fet I shutdown, all depends on what you want.
Of course this is a worst case fix and probably not generally necessary, but, some users do use RCA extensions or metal shield connectors, they will find out the hard way. Also some plastic RCA connectors have exposed parts of the shield.
Gawd...how this become the std for dew strap connectors .....beats me!
