A method for simplifying excited source in EMI simulation of heat spreaders

With the ever-increasing energy consumption and speed of the integrated circuit (IC), the electromagnetic interfere (EMI) introduced by heat spreaders becomes more and more serious. In the EMI simulation of heat spreaders, sources are difficult to obtain as they are actually distributed on surfaces. To simplify the sources, a method is introduced to use a point source instead of sources in a surface when the IC chip area is much smaller than the heat spreader area. An engineering method called “worst case” is used to make a tolerance analysis. Comparison between simulation and measurement is provided for an engineering application, and thus the correctness of the method is verified.