Improving a Test Set to Cover Test Holes by Detecting Gate-Exhaustive Faults

Abstract

Gate-exhaustive faults were used in an earlier work to address test holes that are created when target faults are undetectable. After test generation for target faults is complete, and undetectable target faults are identified, gate-exhaustive faults are selected for gates with undetectable target faults. Tests for gate-exhaustive faults are then generated and added to the test set. The increase in the number of tests varies significantly with the circuit. This paper studies the use of gate-exhaustive faults for addressing test holes post test generation without increasing the number of tests. The procedure described in this paper modifies tests for target faults so as to increase the coverage of the selected gate-exhaustive faults. Experimental results demonstrate the effectiveness of the procedure.