EMI Filter Design, 3rd Edition

19Filter Design Techniques and Design Examples

There are numerous techniques for designing filters. Some are based upon formal methods using numerical analysis; many others are based upon individual process, rules of thumb, and trial and error. Typically, EMI filters are used to reduce conducted emissions to an acceptable level so that a given test specification may be met. EMI filters may also be used to limit inrush current and suppress voltage transients caused by lightning and line transients. The specifications for the allowable interference are generally driven by the power circuit specification. The most common specifications include MIL-STD-461 for military applications, while CISPR and DO-160 are used for commercial applications. Many ...