A Suppression Method for Gate-Source Voltage Oscillation With Clamping Function for GaN Devices

-Gallium nitride (GaN) devices are generally more prone to severe switching oscillations than Si MOSFETS due to their fast switching speeds. Different from Si and SiC MOSFETS, GaN devices typically have a lower maximum gate voltage rating. Taking the Efficient Power Conversion Corporation series as an example, the gate drive voltage is usually 5V, but themaximum voltage rating is 6 V. Therefore, GaN devices aremore susceptible to damage from gate-source voltage oscillation. In this letter, a gate drive circuitwith a clamping function is proposed to suppress gate-source voltage oscillation. The adoptedmethod can not only clamp the gate voltage of the GaN device near the drive voltage to protect the device, but also does not affect the switching speed of the device. The proposed method mainly uses some passive components thatmake the circuit design simpler compared with other active gate driver methods. Finally, the effectiveness of the proposed method is verified by experiments.

Automated summary

GaN devices are more prone to severe switching oscillations due to their fast switching speeds compared to Si MOSFETs. The lower maximum gate voltage rating of GaN devices makes them more susceptible to damage from gate-source voltage oscillation. This letter proposes a gate drive circuit with a clamping function to suppress gate-source voltage oscillation, which uses passive components and simplifies the circuit design compared to other active gate driver methods. The effectiveness of the proposed method is verified through experiments.