Derek Wolfe writes:
This circuit allows a simple switch or a low voltage pulse (5V for example) to control a large dc load. There’s a good explanation of MOSFET transistors and how to use them as a switch here. This is great for connecting a large load to a microcontroller or other logic circuit. Power MOSFET transistors are perfect for this application and can handle high voltage and current (100V, 77A for the NTP6411). This design would be able to power almost any load you can think of (probably even your car).
N-Ch Power MOSFET Switch - [Link]