Reducing inductive coupling skew in wide global signal busses

Abstract

Parasitic on-chip inductance is a major concern for functionality and performance. It affects global signal busses comprised of a large number of nets and traversing long distances most prominently. Due to the difference in separation distance, an attacker affects different signals within a wide bus in varying degrees. This variance in the coupling strength gives rise to an arrival time skew within the victim bus. This paper discusses the use of swizzling to average out the inductive coupling of the attacker over its victims. The paper presents results to show that swizzling significantly reduces inductive coupling skew within a wide global signal bus with zero area and routing resource penalty.