Functional memory array testing

A memory array is considered a collection of RAM chips interconnected via data lines, row-select lines and word-select lines. The stuck-at fault model is assumed for those lines. For each type of line an algorithm is presented to locate the stuck-at fault in the presence of possible stuck-at faults in the other lines and possible faults in the RAM chips. The algorithms are proven to be correct and an analysis of their robustness (insensitivity to other faults in the memory array) is given. The sequence in which the tests have to be performed is determined. A definition is presented of the bridging and open fault models together with an indication of how the presented algorithms can be modified to locate faults of these types.<>