Adaptive approaches for fault detection and diagnosis of interconnects of random access memories

This paper presents three new approaches for testing interconnects of random access memories (RAM). These algorithms are referred to as the Adaptive Diagnosis Algorithm (ADA), the Consecutive Diagnosis Algorithm (CDA) and the Adaptive Diagnosis Algorithm with Repair (ADAR). For diagnosis, ADA requires max{n+1,p} WRITE and max{n,p} READ, while CDA requires max{n+1,p} WRITE and n+p READ, where n(m) is the number of address (data) lines and p is the least integer such that C/sub p/2//sup p//spl ges/m. A different scenario referred to as maximal diagnosis, is considered next. Maximal diagnosis refers as the full diagnosis of all detectable and diagnosable faults in the interconnect with no repair. ADAR utilizes various test iterations to achieve maximal diagnosis; between each pair of iterations, repair of the diagnosed lines takes place. In ADAR, two repair and three test iterations are required. ADAR requires a total of 2n+m+3 WRITE and 3n+m+1 READ.