Characterization of embedded passives using macromodels in LTCC technology

This paper discusses the frequency and time domain response of embedded passive components in a multilayered structure fabricated using low temperature co-fired ceramic (LTCC) technology. A rational polynomial approximation that combines the accuracy of EM solvers with interpolation methods has been used to capture the frequency dependent losses and parasitics of embedded passives in a macro-model. This method allows for a significant speed-up in computation time while using commercial EM solvers. The macromodel with suitable modification has been used to compute the time domain response in SPICE for typical embedded passive structures. Simulation results show good correlation with time domain reflectometry/time-domain-transmission (TDR/TDT) measurements. The behavior of embedded passives in the high frequency operation of transmission lines and voltage divider networks has also been discussed.