Computation of 3-D capacitances of transmission line discontinuities with the boundary element method

With increasing clock rates and scale of integration in microelectronics and PCB-design problems, electromagnetic compatibility achieve more and more importance. Especially since problems of transmission line discontinuities occur during the design process of electronic devices. For an accurate simulation of the circuit model and signal behaviour before the production process, information is needed about transmission line discontinuities which occur as parasitic elements in order to save time and costs for redesign, which is necessary if malfunction arises due to problems of EMC. In this paper attention is focused on the capacitance values of three-dimensional structures which appear as transmission line discontinuities. For this case the method of boundary elements can be applied. The authors have developed a method of calculating the capacitance value of full three-dimensional structures like via´s, connectors and cross-overs using the indirect boundary element method