Prediction of Impedance Characteristics of MLCC Using Multiconductor Transmission Line Theory

This paper proposes an equivalent circuit model of a multilayer ceramic capacitor (MLCC), in which the impedance characteristics of an MLCC could be predicted at design stage before fabrication and measurement. An MLCC can be divided into three regions: end, overlap, and nonoverlap regions depending on the spatial structure of the plates, and the parameters, such as R, L, G, and C are calculated in each region analytically using partial inductance of rectangular plates or/and multiconductor transmission line theory. The measured and EM-simulated impedance of an MLCC coincides to the calculated impedance from the proposed model quite nice over almost the whole frequency range of interests, which proves the validness of the proposed model. Since calculation time is actually nil using the proposed model, compared to the time using the EM simulation, the model can be very useful when one needs to design an MLCC, especially when one needs a lot of iterations to obtain the final design target of an MLCC.