Computer analysis of the dynamic characteristics of a line filter

The dynamical characteristics of a line filter are computer-analyzed by applying the constants of the four-line terminal network method, given a switching-mode power-supply (SMPS) as the noise source. The line impedance stabilization-network (LISN) used to measure line-to-line noise voltage is capable of measuring both the normal-mode and common-mode noise simultaneously. However, to solve SMPS noise problems, these types of noise are separately calculated, and the noise attenuation results are compared with the corresponding measured results, showing satisfactory agreement