MVP: Capture-power reduction with minimum-violations partitioning for delay testing

Scan shift power can be reduced by activating only a subset of scan cells in each shift cycle. In contrast to shift power reduction, the use of only a subset of scan cells to capture responses in a cycle may cause capture violations, thereby leading to fault coverage loss. In order to restore the original fault coverage, new test patterns must be generated, leading to higher test-data volume. In this paper, we propose minimum-violations partitioning (MVP), a scan-cell clustering method that can support multiple capture cycles in delay testing without increasing test-data volume. This method is based on an integer linear programming model and it can cluster the scan flip-flops into balanced parts with minimum capture violations. Based on this approach, hierarchical partitioning is proposed to make the partitioning method routingaware. Experimental results on ISCAS'89 and IWLS'05 benchmark circuits demonstrate the effectiveness of our method.