A Novel SiC MOSFET Crosstalk Clamp Circuit Based on BJT Common -Base and Common- Collector

In this paper, a novel clamping circuit based on BJT common-base and common-collector is proposed for bridge structure crosstalk suppression. According to the principle that the emitter potential remains the same through the common-base and common-collector circuit structure. When crosstalk occurs, the BJTs of the common-base and common-collector will simultaneously turn on, thus, the SiC MOSFET gate voltage clamps at the negative turn-off voltage, which prevents the bridge between the upper SiC MOSFET and lower one from short-through. The clamp circuit is verified both by simulation and experiment under the condition +15/-3V, 400V, and 100kHz. SCH2080 and GlM080120B are used for comparative experiments. The results show that the clamping circuit can clamp the crosstalk voltage below -2V and effectively suppress the crosstalk.