A Novel High-Efficiency Gate Drive Circuit for Normally Off-Type GaN FET

A novel gate drive circuit suitable for a next-generation semiconductor [gallium nitride field-effect transistor (GaN FET)] is proposed and discussed in this paper. The GaN FET has an inherent problem in that its loss increases on the reverse conduction time, if it is driven with a conventional gate drive circuit. This active discharged-type gate drive circuit proposed here can decrease the loss, so that the disadvantage is overcome. The gate drive loss is also analyzed, and the results have errors within the range of 5%. The effectiveness of the gate drive circuit is evaluated by applying a low leakage current (LLC) converter. The results show that the proposed circuit can improve the efficiency at all ranges.