A transparent built-in self-test scheme for detecting single V-coupling faults in RAMs

This paper describes a transparent built-in self-test (BIST) scheme for random-access memories (RAMs) that detects single V-coupling faults. Such faults-as defined by Nair, Thatte, and Abraham (1978)-can be used to model many standard fault types such as stuck bits, transition faults, coupling faults, and pattern sensitivities. Variations of the proposed scheme can generate near-deterministic tests for detecting single 2-, 3-, and 4-coupling faults; in addition, probabilistic tests can be generated to detect single V-coupling faults of arbitrary cell multiplicities V/spl ges/2. The BIST scheme uses Nicolaidis' transformation to make the applied tests transparent; thus the data that was held in the RAM at the start of the test will be restored by the end of the test if no faults are present.<
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