By Eric Bogatin, originally posted on Oct. 1, 2004

All interconnects are always transmission lines and can always be modeled as a transmission line. However, if the interconnect is short enough, it can be approximated by a lumped C or L or a few combinations. In this short paper, we explore the limits to how long an interconnect can be before it can no longer be approximated by Ls and Cs, and the more accurate transmission line model must be used.