Wide-bandgap (WBG) based cascode devices combine the advantages of the gate driveability and reliability of silicon MOSFETs with the power conversion efficiency and switching rate of wide bandgap devices. A low voltage (rated at ~20–30 V) silicon MOSFET drives a vertical JFET for the SiC cascode whereas for the GaN cascode, it drives a lateral GaN HEMT. This paper presents the first systematic comparison of the WBG discrete and module cascodes considering conduction losses, 3rd quadrant operation, switching performance, unclamped switching performance, spontaneous switchings, crosstalk as well as the temperature sensitivities. The results show that the GaN cascode outperforms the SiC cascode considerably in switching performance, however, demonstrates higher conduction losses with more temperature sensitivity in GaN. In this paper, it is also shown experimentally and theoretically that the switching rate in the GaN cascode is more sensitive to the gate resistance compared to the SiC cascode. While turn-ON dI_DS/dt and dV_DS/dt have positive temperature coefficients in the SiC cascode and negative coefficients in the GaN cascode, the SiC cascode is shown to be more UIS rugged, whereas the GaN cascode is incapable of unclamped inductive switching. The impact of unwanted switching on both GaN and SiC cascodes are also shown, indicating that there is a range of optimum gate resistances where un-wanted turn-on and turn-off switchings can be avoided, with the GaN cascode experiencing a higher crosstalk-induced gate voltage due to its higher switching rates.

基于宽带隙 (WBG) 的共源共栅器件将硅 MOSFET 的栅极驱动能力和可靠性优势与宽带隙器件的功率转换效率和开关速率相结合。低电压（额定值为 ~20–30 V）硅 MOSFET 驱动用于 SiC 共源共栅的垂直 JFET，而对于 GaN 共源共栅，它驱动横向 GaN HEMT。本文首次对 WBG 分立式和模块级联共栅系统进行了比较，其中考虑了传导损耗、第三象限操作、开关性能、未钳位开关性能、自发开关、串扰以及温度敏感性。结果表明，GaN 共源共栅在开关性能方面明显优于 SiC 共源共栅，然而，在 GaN 中表现出更高的传导损耗和更高的温度敏感性。在本文中，实验和理论上还表明，与 SiC 共源共栅相比，GaN 共源共栅的开关速率对栅极电阻更敏感。开机时dI _DS / dt和dV _DS / dt在 SiC 共源共栅中具有正温度系数，在 GaN 共源共栅中具有负温度系数，SiC 共源共栅显示出更坚固的 UIS，而 GaN 共源共栅不能进行未钳位感应开关。还显示了不需要的开关对 GaN 和 SiC 共源共栅的影响，表明存在一系列最佳栅极电阻，可以避免不需要的开启和关闭开关，而 GaN 共源共栅会经历更高的串扰 -由于其较高的开关速率，感应栅极电压。