A High-Dynamic Range Current Source Gate Driver for Switching-Loss Reduction of High-Side Switch in Buck Converter

In this letter, a high-dynamic range current source gate driver (HD-CSD) circuit is proposed to reduce the switching loss of the high-side switch in buck converter with wide variation of the gate resistance. Hard switching loss is the major loss in high-side switch and limits the high switching-frequency application of dc-dc converter. Comparing with conventional voltage source gate driver (VSD) and the reported four switches CSD (4S-CSD), the proposed HD-CSD behaves more like the ideal current source driver which can realize the fast switching of power switches to reduce the switching loss. In addition, with proposed HD-CSD, impact of gate resistance that limits the switching speed of the power switch can be greatly reduced. Experimental results are presented to show the power efficiency improvement of buck converter with HD-CSD high-side driver comparing with VSD and 4S-CSD high-side drivers at switching frequency of 1 MHz.