Those who have been exposed to SIL certification and have a preliminary understanding of it know that SIL certification is related to two aspects of enterprise management system and product quality certification. Not only do specific products need to meet functional safety requirements in design, but the entire company's design process and production implementation process also need to achieve controllable failure risks to ensure that the final produced products meet SIL certification requirements 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， Failure Mode, 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 that the failure rate parameters of the product be guaranteed to meet SIL requirements, 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 Modes Effects and Diagnostics Analysis), also known as Failure Modes, Effects, and Diagnostic Analysis, can calculate quantitative indicators.

The object of FMEDA is not system failure, but because random failures follow a probability distribution, we can use FMEDA to analyze whether the probability of a circuit's random failure occurring is within our acceptable range. 

FMEDA is an extension of the FMEA method that incorporates considerations for diagnostic mechanisms. This allows us to determine whether the mechanism has been applied correctly, whether it is insufficient, or whether it has gone too far. In addition, in order to comply with this standard, FMEDA has also taken into account some characteristics of ISO 26262, such as two-point failure.

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