3 滤波和瞬态干扰抑制3.1 引言滤波器可以用来衰减导线上的干扰信号,其性能用衰减量与频率的关系曲线表示。瞬态干扰抑制,比如浪涌保护器(SPD),可以用来衰减导线上的浪涌电压信号,其性能用“允通”电压与时间的关系曲线表示。若不能正确使用滤波器或 SPD,产品的电磁发射和抗扰度性能可能比不使用这些器件时的性能还差。滤波 3 filtering and transient interference suppression 3.1 Introduction Filter can be used to attenuate the interference signal on the wire, the performance of the attenuation with the frequency of the curve. Transient interference suppression, such as a surge protector (SPD), can be used to attenuate a surge voltage signal on a conductor, the performance of which is expressed in terms of voltage vs. time. Without the proper use of filters or SPDs, the performance of the product’s electromagnetic emissions and immunity may be worse than those without these devices. Filter