A new method for testing EEPLAs

Abstract

We present a new method for testing electrically erasable programmable logic arrays (EEPLA) under multiple faults. These include line stuck-at faults, bridging faults, and crosspoint faults. Our proposed method achieves 100% fault coverage of multiple faults by reprogramming the EEPLA many times. The complexity of testing EEPLAs is largely dependent on the number of programming phases, because programming time is much larger than test application time. The proposed method achieves a substantial reduction in programming phases compared with prior methods; and, thereby, in testing time, even though it involves more test vectors. The programming is based on a parallel sequence in which a larger number of crosspoints are tested per phase-a toroidal sequence with which full coverage is still guaranteed. We analyze the method to obtain the testing time as a function of the numbers of input variables, product lines, and output functions.