TECHNOLOGY POSITION SENSING STRAY FIELD IMMUNITY Stray field immunity Sensing is Life Our vision is to create the uncontested leader in optical solutions through bold investments in disruptive innovation and continuous transformation delivering best-in-class profitability and growth. Visit our dedicated website The effect of magnetic stray fields Magnetic stray fields may be generated by magnets, motors, transformers or any current-carrying conductors such as electric power lines. They are of growing concern in one sector of the automotive industry in particular: the number and the strength of the stray magnetic fields is greater in electric and hybrid-electric vehicles (EVs and HEVs) than in conventional cars powered by an internal combustion engine (ICE). Magnetic stray fields influence most position sensors, which are based on Hall effect technology. ams position sensors feature a unique patented technology which protects them against interference from magnetic stray fields. Because the technology behind stray field immunity is integrated into the sensor IC, no external shielding needs to be mounted on the chip. This helps to lower the bill-of-materials and assembly cost of a position sensing system. View POS products Read also our blog post about ams' position sensors Differential sensing architecture ams position sensors offers system designers built-in immunity via differential sensing technology. A position sensor such as the AS5147 has four integrated Hall elements in a north/east/south/west configuration. These elements are only sensitive to the Bz vector of the magnetic field and do not measure the Bx and By vectors. This means that they are inherently immune to stray magnetic field changes in the x and y dimensions. The influence of an external field in the z-direction will be almost exactly the same on all four Hall elements; the sensor calculates the position based on the difference between the outputs of two pairs of Hall elements. Differential sensing can eliminate the influence of almost any external magnetic stray field. Using a sensor based on the differential sensing principle offers various advantages: No external components and no additional shielding needed Higher system safety Higher reliability Cost effective sensor system Small form factor Stray Field Immunity Stray Field Immunity is a unique patented technology by ams, protecting sensors from interfering magnetic fields. Additional external shielding variants are not necessary because the SFI-technology is integrated into the IC, which decrease costs at the final application level. Read article on Sensors Online @ Join our newsletter Subscribe now to the ams Sensing is Life newsletter Sign up ams AG Tobelbader Strasse 30 8141 Premstaetten Austria Phone +43 3136 500-0 Fax +43 3136 525-01 https://ams.com Back to top Sensing is life. ABOUT ams Investor Relations News Center Corporate Responsibility SERVICES Contact Us Sales & Distribution Subscribe ams sensor news QUICK LINKS Search Quality – Certificates Open Positions ams and OSRAM © 2021 ams AG. All rights reserved. Disclaimer Imprint Privacy Policy Cookie Policy Terms of Use .st0{fill:#B5B6B7;} .st0{fill:#5D6A7A;} By clicking “Accept All Cookies (incl. US)”, you agree to the storing of cookies on your device to enhance site navigation, analyze site usage, and assist in our marketing efforts. Cookies Settings Accept All Cookies (incl. US)