有电路图:半桥电路,桥式整流输出,连续工作一段时间就炸机

都是输出整流管炸击穿,mos管GDS也是全部击穿.最常连续考机时间式20小时.失效模式都式一样.
输入220交流,输出300V/500ma,输出桥式整流,用600V/2A两管串联

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整流桥上管波形
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整流桥下管波形
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