Design of SiC MOSFET half-bridge driver and protection circuit

In response to the challenges in designing silicon carbide (SiC) MOSFET driving circuits, such as high difficulty in design, susceptibility to crosstalk, incomplete protective functions, and the issue of full domestic production, a half-bridge driving and protection circuit for silicon carbide MOSFETs has been designed based on domestic chips. This paper focuses on analyzing and summarizing the principles and models of active Miller clamp protection, desaturation protection, and bridge arm interlock protection for silicon carbide MOSFETs. The driving circuit not only isolates the primary and secondary signals but also uses high and low levels of 18 V/-3.3 V to control the upper and lower bridge arm silicon carbide MOSFETs. It integrates functions such as undervoltage lockout, desaturation protection, bridge arm interlock, and active Miller clamp protection. The parameter comparison and function test were carried out with the international advanced level of Wolf Speed's silicon carbide MOSFET driver board CGD1200HB2P-BM2. The experimental results show that the switching parameters of the circuit are similar to CGD1200HB2P-BM2 driver board, which can meet the driving requirements of silicon carbide MOSFET and can trigger the protection function reliably. This circuit has been applied to drive silicon carbide MOSFET.