关于On semi NCP1337 AND NCP1377

各位大虾:
    本人用1337遇到了一个问题,开机启动瞬间,输出整流管的反向电压尖峰很大,加吸收电路作用不大.而用1377没有这样的问题,不加吸收电路,反向电压也很小.请看图片(无吸收的反向电压),有方法请指教,谢谢!
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