In this paper a FEM based method is proposed using HFSS 3D to precisely simulate passive components considering frequency dependent characteristics such as variation of relative permeability of the core, skin and proximity effect in copper layers, inductive and capacitive coupling between all turns and layers including the parasitic capacitor with the ground plane. An equivalent SPICE model of this simulation is obtained that precisely represent HFSS results. This model provides an opportunity to accurately implement the passive components in time domain circuit simulations.
