Those who have been exposed to SIL certification and have a preliminary understanding of it know that it is related to the certification of enterprise management system and product quality. Not only does the specific product design meet the requirements of functional safety, but the entire design process and production process of the company also need to achieve controllable failure risk, ensuring that the final produced product meets the requirements of SIL certification from these two aspects.

So if a company needs to simplify the SIL certification process due to cost and time factors, as long as it is recognized by customers, it can achieve this goal through FMEDA evaluation.

FMEDA, Failure Modes Effects and Diagnostic Analysis

The Failure Mode, Effects and Diagnostic Analysis (FMEDA) method plays an important role in functional safety work. It qualitatively analyzes the failure risk and diagnosability of functional safety products, and provides effective data support for the calculation of average failure probability and safety integrity level.

So why do we say that FMEDA evaluation can be seen as a simplification of SIL certification? The reason is that FMEDA evaluation itself is a key element in SIL certification. Through such an evaluation, we can obtain the failure rate and failure mode of the product, and determine the conformity of the product design. In general, if customers do not have clear requirements for the controllability of the product implementation process, but only require the failure rate parameters of the product to be guaranteed and meet the requirements of SIL, we can also obtain the desired results through FMEDA evaluation. Compared to SIL certification, enterprises save a lot of money and time costs.

FMEDAApplication cases

ISO26262 requires multiple quantitative indicators for random hardware failures during the hardware development phase. FMEDA (Failure Mode Effects and Diagnostic Analysis), also known as Failure Mode, Effects, and Diagnostic Analysis, can calculate quantitative indicators within it.

The object of FMEDA is not aimed at system failure, but since random failure follows a probability distribution, we can use FMEDA to analyze whether the probability of random failure in a circuit is controlled within our acceptable range. 

FMEDA is an extension of the FMEA method, which incorporates consideration of diagnostic mechanisms. This allows us to determine whether the addition of diagnostic mechanisms is correct, insufficient, or excessive. In addition, to comply with this standard, FMEDA has also incorporated considerations for some features of ISO 26262, such as dual point failure.

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