Quick detection of faults in combinational networks designed in minterm format by computing a single novel parameter

Abstract

This paper reports on the development of a novel scheme as an alternative to Susskind's method [A.K. Susskind, Testing by verifying Walsh coefficients, Proceedings of the 11th Annual Symposium on fault-tolerant computing, June 1981, pp. 206–208.] for detection of struck-at faults in combinational logic circuits. The main idea in the present scheme is to extend an existing design of the combinational network under test in minterm format by some logic checking the correctness of all input–output mappings by computing only one novel parameter after cycling through all 2 ⁿ input combinations of a circuit with n inputs. Thus the present scheme uses 2 ⁿ n-bit input patterns once to a circuit while Susskind's method uses twice that many. So it provides substantially less work than that needed in Susskind's method. Furthermore, the tester needed to implement the present scheme is a simplified version of that needed in Susskind's method.

Keywords:

• combinational network
• minterm
• s-a-0 and s-a-1 faults
• Walsh function
• Walsh coefficient

2000 AMS Subject Classification :

• 03G05
• 06E30