A parallel built-in self-diagnostic method for embedded memory arrays

In this paper, the authors propose a new built-in self-diagnosis method to simultaneously diagnose spatially distributed memory modules with different sizes. Based on the serial interfacing technique, the serial fault masking effect is observed and a bidirectional serial interfacing technique is proposed to deal with such an issue. By tolerating redundant read/write operations, they develop a new march algorithm called DiagRSMarch to achieve the goals of low test signal routing overhead, tolerable diagnostic time, and high diagnostic coverage. It can be proved that DiagRSMarch can identify all stuck-at, transition, state coupling, and dynamic coupling faults occurring in all memory arrays. Experimental results also demonstrate that the test efficiency of DiagRSMarch is highly dependent on memory topology, defect-type distribution, and degree of parallelism.