An equivalent circuit model for terminated hybrid-mode multiconductor transmission lines

An equivalent circuit for terminated hybrid-mode multiconductor transmission lines is presented. Existing CAD packages, such as SPICE, can be used for its implementation. Model parameters can be found from either a TEM or a full-wave analysis of the transmission lines. The equivalent circuit is used to simulate multiconductor microstrip for applications in high-speed integrated circuits. The accuracy of the TEM approximation is investigated for time-harmonic as well as pulse signal propagation. For some cases examined, the time-harmonic signal propagation data obtained using the TEM approximation become quite inaccurate at frequencies in excess of 20 GHz. The TEM approximation is adequate, however, for pulse propagation with 15-ps risetime and falltime pulses on the geometries investigated.>