Re-Optimization Algorithm for SoC Wrapper-Chain Balance Using Mean-Value Approximation

Balanced wrapper scan chains are desirable for system-on-chip (SoC) testing because they minimize the time required to transport the test data. A new heuristic algorithm is proposed based on mean-value approximation and implement fast re-optimization as a subsequence of an earlier best-fit-decrease (BFD) method. The mean length of each scan chain was introduced as an approximation target to balance different scan chains and hence saved testing time. Experimental results present both for assumed arbitrary cores and cores from ITC'02 benchmark and show the effectiveness of the algorithm. The proposed algorithm can provide more balanced wrapper design efficiently for the test scheduling stage.