An integrated GMR (Giant-Magnetic-Resistance) sensor is presented for 3600 angular measurements of rotating magnetic fields in automotive applications. The spin-valve GMR-layers are directly applied to a standard semiconductor 0.22,um CMOS process by vertical integration of the sensorbridges atop of active circuitry. The entire integrated anglesensor comprises 2 orthogonal magnetized GMR-bridges for sine and cosine signal measurements, and the subsequent signal conditioning circuitry. The entire angular sensor is designed to work in harsh automotive environment in a temperature range of -40°C to 150°C. The strength for best precision covers a wide range from 20 to 50 mT. The resulting angular information itself can be obtained by SPI-readout and calculating the arc-trigonometric function of the bridge signals with a resolution of > 13bit in an auxiliary microcontroller. After individual calibration to compensate for production spread an accuracy of typical 0.50 is achieved.I.

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This work reports on inkjet- and 3D-printed force/pressure sensing devices. The employed printing processes can enable cost- and resource-efficient, fast and flexible designs compared to solid-state technology which is used as a reference design. The pressure sensing devices are realized as either 3D-printed steel or 3D-printed ceramic diaphragms. Both designs thus withstand harsh environmental conditions and elevated temperatures. Additionally, the increased size guarantees less sensitivity to dirt or moisture due to the larger diameter of the diaphragms. The hardware used for the capacitive sensor read-out is based on a shunt measurement system and subsequent demodulation. This architecture enables long cabling, allowing for large parasitic capacitances, without significant loss of transferred signal power, due to the employed power matching to the transmission line. Physical analyses such as contact angle measurements, profilometer measurements, and focused ion beam analysis are done to characterize the resulting printed surfaces. Then, the response of both designs is evaluated by applying force on the diaphragms surface using a moveable load cell. The gathered results are also compared to finite element method simulations.

Abstract. In this chapter, the various automotive applications for GMR based sensors are presented. The different applications have different requirements which are reflected in the individual sensor concept and features. The advantage of GMR based magnetic sensors over conventional silicon based Hall sensors is shown.