Building upon previous work that used login implications to improve the reliability of digital circuits in detecting online faults, this paper adds diagnosis properties to help localize the portion of the circuit where the fault has occurred.

An in-depth analysis of related work in the area is presented, allowing the reader to find pointers to the authors’ previous contributions, as well as to other relevant approaches in the area.

Then, the proposed approach, which builds on previous solutions, is presented. The authors briefly discuss a more comprehensive view, enabling the reader to understand the whole proposal, without having to refer to other documents. The paper introduces the use of logic implications to support the online detection of a subset of all possible faults. The core of the proposal focuses on providing diagnostic information to understand what part of the circuit has actually been hit by the fault. Logic implications should be introduced considering the need to be able to isolate the fault, which has an impact on the set of tests used to verify the circuit.

The discussion is easy to follow, in part because of the small but useful examples. The experimental results section provides an in-depth evaluation of the effectiveness of the proposed approach when applied to a set of ISCAS85 benchmarks. The adoption of a well-known benchmark suite allows for future comparisons by other researchers in the area, although it might feel a little bit dated and “limited” (the authors justify the reasonability of the choice). In fact, it would have been interesting to see the performance of the approach on complex circuits, both in terms of the quality of the output and the computational complexity of the solution strategy.

As a final note, the proposed approach is compared to the traditional technique of duplication with comparison, which remains a commonly used reference.