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Functional safe systems fulfilling the ISO 26262 standard are getting more important for automotive applications where additional redundant and diverse functionality is needed for higher rated ASIL levels. This can result in a very complex and expensive system setup. Here we present a sensor product developed according ISO 26262. This sensor product comprises a two channel redundant and also diverse implemented magnetic field sensor concept with linear digital outputs on one monolithically integrated silicon substrate. This sensor is used for ASIL D applications like power-steering torque measurement, where the torque is transferred into a magnetic field signal in a certain magnetic setup, but can also be used in other demanding sensor applications concerning safety. This proposed and also implemented solution is beneficial because of implementation on a single chip in one single chip-package but anyway fulfilling ASIL D requirements on system level.

Functional safe products conforming to the ISO 26262 standard are getting more important for automotive applications wherein electronic takes more and more response for safety relevant operations. Consequently safety mechanisms are needed and implemented in order to reach defined functional safety targets. To prove their effectiveness diagnostic coverage provides a measurable quantity. A straight forward safety mechanism for sensor systems can be established by redundant signal paths measuring the same physical quantity and subsequently performing an independent output difference-check that decides if the data can be transmitted or an error message shall be sent. This paper focuses on the diagnostic coverage figure calculation of such data correlation-checks for linear sensors which are also shown in ISO 26262 part5:2011 ANNEX D2.10.2.

Position detection and control is necessary in modern automotive applications because of remotely controlled actuators, such as window lifters or windshield. In recent years, the demand for reliable actuators for safety critical systems, such as power steering systems, has also increased significantly. This creates a growing demand for fast, accurate and efficient servo motor systems that are increasingly smarter, smaller and cheaper. One interesting option is to use Giant Magneto Resistive (GMR) angle sensors to replace the resolvers, Hall, inductive and Anisotropic Magneto Resistive Effect (AMR) Sensors commonly used today for shaft-angle measurements. In principle, there are functional differences among various angle measurement technologies; thus, the effect of switching between them needs to be analyzed.