A Pre-Charge Tracking Technique in the 40MHz High-switching 48-to-5V DC-DC Buck Converter with GaN Switches for Reducing Large Self-commutation Loss and Achieving a High Efficiency of 95.4%

for automobile applications, a high-switching 48-to-5V DC-DC buck converter is implemented with 0.5µm CMOS process and 0.5µm Gallium-Nitride (GaN)-on-Si process, including the pre-charge tracking technique, temperature-dependent controlled gate driver, and adaptive relaxation gate-drive control technique, which can increase the efficiency by about 8.8% and ensure the current capacity of Enhance-GaN (E-GaN). The inner local negative feedback loop can enhance the reliability and reduce the RON by 12mΩ. The peak efficiency is as high as 95.4%.