Load Adaptive Gate Driving Method for High Efficiency Under Light-Load Conditions

In this paper, a new gate driving method to improve light-load efficiency is proposed for the power conversion system with a standby converter. The proposed method reduces the gate driving voltage of power MOSFETs and the operating voltage of controller ICs under light-load conditions by adjusting the auxiliary output voltage of the standby converter. Therefore, the gate driving loss on MOSFETs and the loss on controller ICs are significantly reduced without the degradation of performance in the main power stage. To confirm the validity of this paper, the dc/dc server power supply with an input of 48 V, an output of 12 V/60 A for the dc/dc stage, and an output of 5 V/3 A for the standby stage is experimented.