ABSTRACT
The first step is to find the filter type needed for the application. If a test specification is in place, this tells the electromagnetic interference filter designer what specifications the filter must meet, such as MIL-STD-461, Comite International Special des Perturbations Radioelectriques, Federal Communications Commission, or some other. The specification for either the capacitance to ground or the maximum current on the ground lead varies considerably, depending on the function of the equipment. Medical specifications are the hardest to meet, especially if the equipment is attached to the patient. Even the larger filters—high-current screen room type—are often specified to meet the 220-A specification, which is 50 ohms. The filter structure has been selected to show that the two capacitor values are split— half value in front and back. The chapter shows the process of generating an equation that gives the loss in dB.
