Before gallium nitride (GaN), the silicon (Si) MOSFET was the standard for power in adapter applications for decades. As a result, many of the existing controllers in the marketplace, including power factor correction (PFC) and DC-DC controllers, have already integrated silicon drivers into the controller chip. These controllers have proven to be a cost-effective and complete solution. However, the poor figure-of-merit (FOM) of Si MOSFETs limit the controller’s capability of high switching frequency performance to meet the requirement of high-power density vital to modern power systems…