Reduced RC Models for IC Interconnections with Coupling Capacitances

The transmission behavior of interconnections in integrated circuits is often determined by their distributed RC effects. In this paper, we present a modeling technique, for incorporation in a layout-to-circuit extraction program, that accurately represents these effects. The method consists of first replacing IC interconnections by a complex RC network and then transforming this complex RC network into a simple RC network. It extends previous work in that (1) besides preserving the Elmore time constants between the terminals of the interconnections, the method also preserves the total resistances between the terminals and the total capacitances, and (2) the method handles ground capacitances as well as coupling capacitances.