# Transistors: How does the gate work?

Two questions:

First, how does the gate provide a positive charge by running a current through it? I really just don't see how this positive charge could be achieved, unless you had some sort of battery in the gate itself and attached a wire to donate some of the electrons flowing through to the cathode of some other battery. Is it possible to get electrons out of the gate by some other means?

• perhaps this should be asked on Physics.SE – user15489 Apr 16 '15 at 9:18
• Is there a significant $I_{GD}$ in FETs? In contrast to BJTs, the former aren't current-, but voltage-controlled. A conducting channel between source and drain is typically induced by applying a (positive) voltage between gate and source. – Klaus-Dieter Warzecha Apr 16 '15 at 9:29
• @KlausWarzecha Applying a positive voltage on the gate means that electrons are moving into the gate, right? But wouldn't that make the gate more negative? – extremeaxe5 Apr 16 '15 at 10:30
• Why wouldn't the electrons move to the positive voltage source? Instead of Physics SE I might suggest Electrical Engineering. But, you seem to have a number of concepts mixed up with each other, so a little more thought should be placed before re-asking the question. – Jon Custer Apr 16 '15 at 13:37