Here below what I gathered from a comprehensive study of the great amount of literature/IEEE publications about this topic it is possible to get from the web.
#Ltspice ac source parameter description how to#
LTspice models allow engineers to evaluate what’s the change in performances using the effective load ( how to calculate the real load vs frequency is a different topic to be discussed separately once I find time, sorry) To be honest I remember only 1 EMI Filter manufacturer still showing insertion loss with different source/Loads as per CISPR 17 (50/50 ohm or 0.1/100 Ohm). Not only because these models are a powerful way to facilitate EMI Filters PCB integration and insertion loss prior simulation but also because, entering into these models details, it is possible to study carefully the electro-magnetic properties of CMC representing the most important component of EMI Filters (especially in Medical applications) where leakage current limits inhibits the help coming from CYs.īefore coming along our analysis, it is worth to repeat once again, the fact that evaluating EMI Filters on source/load 50 ohm load represents the only (commercial) possible way to compare performances but the majority part of you knows it is required to test Insertion loss on the real loads (lower or higher impedance).
Recently I ‘ve read several posts about LTSpice models for Common Mode chokes (CMC) and EMI Filters.