请教MOSFET驱动的问题,一个H桥,我发现有上下桥共通的现象,但不知是不是密勒电容所至.

如下图,不知道为什么Q2管的GS电压一直为0V,可Q2管的正向电流会超过3A以上,总是烧管.请问是什么问题呢?会不会是Q2管的密勒电容所至?
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