I would like to use N-channel as a touch switch which will be an input to the microcontroller. Currenty I am concerning about power draw. The whole device will be in metal case and I am planing to connect this case to battery GND. Now, if I use the Nmos connected like this (R3 is a touch plate):
i will have in off state power consumption on R1. Only way how to avoid this comsumption is put a touch plate instead of R2 and switch to VCC. I am asking, does make sense to make a metal case connected to VCC instead of GND? Or is better to use a P-channel mosfet wich will be grounded during on state? Is there a way to use high impedance of uC imput to make it without mosfets?
I forgott to clarify, the touch plate will be made like mosfet gate to metal case touch switch.
Until now I see the most suitable solution to use a P-channel like this (no waste, no need to low finger resistance):