Electronic – Why use a N channel MOSFET as high side H bridge switches


I've seen N channel MOSFETs as high side switches of H bridges quite often, which requires a charge pump to drive. Wouldn't a P channel MOSFET be easier, simply isolating the microcontroller command from the gate source voltage? Why use the N channels instead then?

Best Answer

P-channel MOSFETs tend to have a higher Rds(on), making them less efficient (for the same price). For a small H-bridge, the simplicity of using them makes them practical

However, for high power applications, the extra complexity of driving N channel FETs can be justified by improved efficiency from lower Rds(on).