The NMOS is preferred because it can handle much higher voltages and negative currents, whereas the NPN BJT is limited to low-voltage, positive-current applications.

The NPN BJT is voltage controlled (requires , while the NMOS is current controlled (requires ), making the NMOS more efficient.

Both are equal in terms of power, but NMOS is cheaper to manufacture and so is the better choice to support maintenance and repairability.

The NMOS is easier to manufacture, but the NPN is a more efficient switch because its “on” state power consumption is typically zero.

The NMOS’ “on” state power consumption is only due to . The NPN’s “on”state power includes , making it less efficient.

The NMOS has a lower “on” state power consumption, primarily because it is a voltage-controlled device. Its insulated gate draws negligible current at DC, whereas theNPN BJT is a current-controlled device, that requires a continuous base current () to stay “on”, which consumes power.