High-Side MOSFET Circuit

P-Channel MOSFET

High-Side MOSFET circuits must be switched with a P-Channel MOSFET, which can be controlled by an N-Channel MOSFET:

When the N-Channel gate is pulled LOW, it's off, and nothing flows through it. When the gate is pulled HIGH, then electrons are allowed to flow from GND to the P-Channel gate, and it turns on, in turn, energizing the load.