A test generation procedure for avoiding the detection of functionally redundant transition faults

We present a test generation procedure for transition faults that minimizes the detection of functionally redundant transition faults in scan circuits. The procedure uses broadside testing. We also propose rules for identifying dominance relations between functionally redundant transition faults and functionally detectable transition faults. Dominance relations can provide two types of lower bounds. (1) A lower bound on the number of functionally detectable transition faults that cannot be detected without detecting any functionally redundant transition faults. (2) A lower bound on the number of functionally redundant faults that have to be detected if all the functionally detectable faults are detected. In our experiments with ISCAS-89 and ITC-99 benchmark circuits we achieve both of the lower bounds for almost all the circuits considered.