A decomposition and reconstruction scheme for broadband modeling of on-chip passive components using the modified T-equivalent circuit topology

This paper presents a state-of-the-art technique for broadband modeling of on-chip passive components. The proposed decomposition and reconstruction methodology can efficiently and accurately establish the broadband SPICE model for an arbitrary multi-port reciprocal component over an extremely large bandwidth. The idea is to decompose a multi-port network into a number of one-port networks which can be lumped modeled simply and easily. Then a reconstruction process, based on the modified T-equivalent circuit topology, is invented to combine these one-port lumped models into a broadband multi-port model. In this modeling study, the S parameters for a series of passive components including spiral inductors, MIM capacitors, bifilar transformers and baluns, fabricated using a 0.18 μm RF-CMOS foundry process, have been measured up to 20 GHz. The modeled S parameters agree quite satisfactorily with the measured results over the entire measurement frequency range.