Hello, I am trying to switch on\off a 5V load using an N-channel MOSFET, with a microcontroller supplying the logic signals (also 5V). I soon realized, after connecting my microcontroller directly to the gate of the MOSFET, that something was very wrong . After a little research it seems that I need a driver circuit, so I attempted to build this one: http://incredulist.blogspot.com/2012/10/high-side-switching.html With the collector of the PNP transistor attached to my oscilloscope, everything seemed fine—the voltage alternated between a full 12V and then down to 0V, just as it should. However, when I wire it to the gate of the MOSFET, the drain stays at 5V... A 100-ohm pull-down resistor on the gate helps a *little* (though it gets HOT), but the MOSFET drain won't drop below 2.5V. Is my problem that the PNP transistor in the diagram can't sink enough current? (I've attached a schematic of my MOSFET circuit in case it's needed).