Three-level driving method for GaN power transistor in synchronous buck converter

The emerging Gallium-Nitride (GaN) based power transistors offers the potential to achieve higher efficiency and higher switching frequencies than possible with Silicon MOSFET´s. This paper will discuss the GaN device characteristics, and based on this, the driving method will be discussed. Then a three-level driving method is proposed to overcome the high reverse conduction loss issue of the GaN power transistor. Finally, a 12V to 1.2V Synchronous Buck converter with a full load current of 20A is built to verify the proposed method. The experimental results show that the proposed method is necessary and effective for efficiency improvement in high switching applications of GaN power transistor.