I need to control an LED with a N-channel mosfet, but need the cathode to be connected to ground. I learned to do it this way:
but when I tried to connect it differently to keep the cathode of the LED grounded like this, there was a big voltage drop across the mosfet for some reason:
Exactly why does this happen? Would I be correct in thinking that using a P-channel mosfet would serve my purpose?