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Showing posts with the label HW Evaluation

The inconclusive debate - Class II or Class III

ISO26262’s HW Evaluation talks about 3 Classes of HW Components – Class I, II or III. There are 3 attributes we must use to determine this Class. Once we identify the Class, we need to evaluate them accordingly. At a first glance, this approach sounds simple and straight forward. However, when we read deeper, we realize that the ISO Standard is ambiguous in describing how to determine HW Classes. While it does give 3 attributes, it does not mention how to correlate them. This makes it difficult to conclude how to classify some of the HW elements, especially the medium and high complexity HW ICs. In this blog, we have shared our 2 cents on HW classification of Class II and Class III elements. HW elements are classified based on 3 attributes: Complexity Ease of Identification of failure modes and  Availability of Safety mechanisms Based on these 3 attributes, Class of a HW element is identified as shown below. Can you see the gap in the above table? It does not define how to correlate th