Top-K Aggressors Sets In Delay Noise Analysis

We present, in this paper, novel algorithms to compute the set of "top-k" aggressors in a design. We show that the computation of the set of top-k aggressors is non-trivial, since we must consider all permutations of aggressors that are coupled to a critical path. Also, different sets of aggressors contribute different amounts of noise to each critical path and a brute-force enumeration to obtain the set of top-k aggressors has impractical runtime. Our proposed approach uses two key techniques to reduce the runtime complexity: Firstly, we model the delay noise propagated from a victim net to its fanout net by a so-called pseudo aggressor which simplifies our problem formulation significantly. Secondly, we define a dominance property for aggressor sets, which imposes a partial ordering on the aggressor sets and allows us to efficiently prune the enumeration space. We then demonstrate the effectiveness of our proposed algorithm on benchmark circuits.