DESIGN AND FABRICATION OF ALL GAN INTEGRATED DC-DC POWER CONVERTER

Abstract

In order to further utilize the advancing GaN-based device technology in power conversions, the level of integration among main switches, control circuits and passive components is required to be as high as possible. The main objective of this thesis is to develop the all GaN integrated DC-DC buck converter using AlGaN/GaN MIS-HEMTs. Firstly, the realistic interface traps configuration scheme is proposed and experimentally verified. Secondly, the design of DC-DC buck converter with integrated high-side gate driver, pulse-width-modulation feedback control and over-current protection circuits is proposed and numerically analyzed. Thirdly, the over-current protection scheme and AlGaN/GaN MIS-HEMTs with embedded current sensing structure are designed and experimentally verified. Lastly, the all GaN integrated DC-DC buck converter is fabricated and characterized. The converter can realize stable DC-DC buck conversion even with abrupt variations in input line voltages and load conditions. The converter can be protected within one cycle period against over-current conditions.