High Frequency Broadband Research Of Emi Filter

EMI filter is a low pass EMI (electromagnetic interference) passive devices, caneffectively inhibit the transmission signal line, power line of conduction interferencesignal and interference signal. In order to adapt to China’s aviation, aerospace and otherweapon system for supporting electronic system miniaturization demand, there is anurgent need to develop the miniaturization, high reliability, high frequency broadbandEMI filter, grasp the development and production of the relevant core technology andprocess.ThThis paper is in reponse to these problem of high frequency, broadband EMIfilter as the main research object, in thorough analysis EMI filter design based on theprinciple of filter parameters, EMI, structure design and test technology to do thecreation and exploratory study. Main contents are:1. The effects of rare earth elements on EMI filter attenuation characteristicsimulation design (design L, C, R circuit parameter, using computer simulationtechnology (ADS) product attenuation characteristic simulation.2. studied the feed-through capacitor chip high precision alignment of printingtechnology and (EMI) filter assembly welding technology (using CAM technology tomanufacture high precision automatic printing equipment, to design and manufacture ofspecial welding fixture, thereby completing the filter manufacturing process.3. Study on attenuation characteristic testing technology to design and manufactureproducts (attenuation test fixture, thereby improving the testing accuracy of the testattenuation index..4. Study on reliability design of EMI filter technology (mainly for its core element,multilayer ceramic chip capacitor for reliability optimization design, and the material ofthe thermal expansion properties of material, preferably to ensure product reliability.5. production of EMI filters technology index: Frequency range（MHz）：1～8000，cut-off frequency（MHz）：500，insert attenuation：30dB；Frequency range（MHz）:1～6000：cut-off frequency（MHz）：470；insert attenuation：28dB. The production results show that the product design to fully meet the technical requirements, and can replacethe similar foreign products, to meet the user requirements of the whole system.