Augmenting scan path SRLs with an XOR network to enhance delay fault testing

In this paper, we present a technique to enhance transition delay and stuck-open fault testing in an LSSD environment. To reduce shift dependency in the scan path, thereby improving transition quality, a re-arrangement heuristic combined with a one level XOR network is proposed. The method is hierarchical, combining a simple re-arrangement, heuristic driven local reconfiguration, and finally a circuit modification to improve delay fault testing.