最近做了块板子,在Buck电路中用IR2110驱动IGBT,电路如图示
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其中VDD和VCC_IR是12V电源,下图是主电路上电前(1)和上电后(2)的HO波形图:
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Buck输入电压是17V,请问为什么会出现纹波,是因为IR2110中电容参数不对吗?还是因为主电路中干扰.另外,我的Buck电路输入17V时,输出为什么达到了6V(占空比20%).请各位有经验的长辈们指教.