A hybrid concurrent error detection scheme for simultaneous improvement on probability of detection and diagnosability

摘要

In this work we propose a hybrid concurrent error detection (CED) scheme that combines the implication-based method with the parity check method. The parity check method is easy to implement and has high probability of detecting errors, while the implication-based method has high flexibility to be easily integrated with other CED methods for improidng the probability of detecting errors. In addition, fault diagnosis capability can even be enabled by integrating implications. We show that by combining these two methods, not only the probability of detecting errors can be significantly increased, but also the diagnosability of the target circuit can be effectively enhanced. A systematical flow is developed to add the required checking logic of implications into the most appropriate locations in the target circuit for detecting undetected errors by the parity check method. This minimizes the total number of the employed implications and thus the incurred area overhead. The experimental results show that 89.08% of area overhead is required yet the probability of detecting errors is improved from 88.32% to 97.73% by the proposed hybrid scheme. The results also show that the achievable diagnosability of our scheme enhances from 91.79% to 96.36% on average. More than 200 equivalent faults also become distinguishable in our scheme.