Redundant and Diverse Magnetic Field Digital Linear Hall Sensor Concept for ASIL D Applications

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. The realized aspects of redundancy and diversity as well as the proof to fulfill these safety-requirements are presented in the paper chapters.