EM C desig n of sw itching pow er supply

Z Ou, Wan -Zhen, Sh Zhan-You, Yun -F Xu, Eng
T his pa per analyses the EM C w ave of t he sw itching pow er supply and establishes the cir cuit model that results in co mmon mode interference and series mode inter fer ence. T hen pro vides the concrete solution: making use o f sing le or double level EM I filters can filt er co mmon mo de interfer ence and series mode inter ference effectively. F inally, it int roduces the method to choose the dev ice par amet er in the EM I filters. T he ex per iment indicates that it can r educe EM I by
more » ... can r educe EM I by 40 dBV by the simple EM I wav e filter. H ow ever , using the impro ved EM I wave filter can r educe EM I by 50~ 70 dBV.