New Block-Based Statistical Timing Analysis Approaches Without Moment Matching

With aggressive scaling down of feature sizes in VLSI fabrication, process variation has become a critical issue in designs. We show that two necessary conditions for the "Max" operation are actually not satisfied in the moment matching based statistical timing analysis approaches. We propose two correlation-aware block-based statistical timing analysis approaches that keep these necessary conditions, and prove that our approaches always achieve tight lower bound and upper bound of the yield. Especially, our approach always gets the tight upper bound of the yield irrespective of the distributions that random variables have.