A novel method for equivalent circuit synthesis from frequency response of multi-port networks

Interconnects in electrical/electronic systems are commonly modeled in frequency-domain. However system level electrical analysis involving signal and power integrity simulations are typically done in time-domain, which calls for circuit level representation of the interconnect networks. In this paper, we demonstrate a novel iterative method that approximates a multi-port frequency responses to an equivalent circuit netlist consisting of the basic elements - resistor, capacitor and inductor. Each iteration picks a few consecutive points from the frequency response, identifies a local transfer function matching their response and synthesizes it as a branch in the approximant. A 3-port network comprised of power delivery planes with three vias is synthesized. The equivalent circuit response closely matches the given frequency response, demonstrating the potential of the method for signal/power integrity modeling and simulation of interconnect networks.