CURRENT: a test generation system for I/sub DDQ/ testing

This paper presents an I/sub DDQ/ test generation system for scan-based circuits, called CURRENT. A library-based fault modeling strategy is used to specify a realistic target fault set, which encompasses intra-gate shorts (for example stuck-on faults, gate-drain shorts) as well as inter-gate shorts (bridging faults). CURRENT consists of a fault simulator and a deterministic test generator. The fault simulator can be used to determine the fault coverage of a given test set or to generate test patterns for easy-to-detect leakage faults. The deterministic test generator is able to generate tests for hard-to-detect leakage faults and to identify redundant leakage faults. Furthermore, CURRENT is able to generate small test sets through the use of a new test set compaction technique, thus reducing the total test application time for I/sub DDQ/ testing. Experimental results show that CURRENT is able to generate small test sets with a test efficiency of 100% for each of the benchmark circuits with up to 2,400,000 considered leakage faults.