Delay monitoring scheme for critical path timing margin

Abstract

A monitoring system for monitoring delay of critical path timing margins can include a plurality of adaptive monitoring circuits, where each adaptive monitoring circuit is coupled to a corresponding one of a plurality of paths in a circuit. Each adaptive monitoring circuit can include a first delay element designed to cause a mean timing margin of the plurality of N paths in the circuit to be within one minimum mean unit delay; a second delay element coupled to the first delay element and designed to add a mean delay of k*σ; a set-up capture element capturing an output of the second delay element; and a set-up warning comparison element that outputs a set-up warning signal when the output of the set-up capture element and a shadow capture element or a capture element of the corresponding one of the plurality of paths do not satisfy an expected condition.