Efficiency improvements for multiple fault diagnosis of combinational circuits

We present two techniques for improving the efficiency of the previous method for multiple fault diagnosis of combinational circuits. (1) Three new rules for deducing the valves at the internal lines are added to the previous deduction rules. Experimental results show that 2.6~15.2% improvements in resolution are achieved by adding the enhanced deduction rules without probing the internal lines. (2) A probing method for diagnosis is proposed to improve the resolution obtained by the method (1). Preliminary experimental results show that about 0.1~9.4% improvements in resolution are further achieved by probing about 4~111 internal lines in the circuit