Fast vectorless power grid verification using maximum voltage drop location estimation

Power grid integrity verification is critical for reliable chip design. Vectorless power grid verification provides a promising approach to evaluate the worst-case voltage fluctuations without the detailed information of circuit activities. Vectorless verification is usually required to solve numerous linear programming problems to obtain the worst-case voltage fluctuation throughout the grid, which is extremely time-consuming for large-scale verification. In this paper, a maximum voltage drop location estimation approach is proposed for efficient vectorless verification. The power grid nodes are grouped into disjoint subsets, and an estimation strategy is utilized to roughly locate the nodes which have the worst-case voltage drop in each group. Consequently, the verification problem size can be significantly reduced compared with accurate verification. Experimental results show that the proposed approach can achieve remarkable speedups with acceptable accuracy loss.