An Efficient Linear Time Algorithm for Scan Chain Optimization and Repartitioning

David Berthelot, Samit Chaudhuri, Hamid Savoj

Abstract: Proposes a linear-time algorithm for post-placement scan chain optimization that works efficiently on large designs and that allows user-specified tradeoffs between runtime and solution quality. This algorithm is also efficiently applied on scan chain partitioning. Presents repartitioning algorithm that takes advantage of the linear-time scan chain optimization algorithm presented in the first part. The idea is simply to connect all the scan flipflops of all the scan chains together in a new chain. Then the algorithm optimizes this new chain and splits it in individual chains of the size of the initial chains. Later it assigns individual chains to their closest scan primary input/output pair.