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The increasing legal requirements for safety, emission reduction, fuel economy and onboard diagnosis systems push the market for more innovative solutions with rapidly increasing complexity. Hence, the embedded systems that will have to control the automobiles have been developed at such an extent that they are now equivalent in scale and complexity to the most sophisticated avionics systems. This paper will demonstrate the key elements to provide a powerful, scalable and configurable solution that offers a migration pass to evolution and even revolution of automotive Sensors and Sensor interfaces. The document will explore different architectures and partitioning. Sensor technologies such as magnetic field sensors based on the hall effect as well as bulk and surface silicon micro machined sensors will be mapped to automotive applications by examples. Functions such as self-test, self-calibration and self-repair will be developed.

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 signal delivery and quality of sensor data is of growing importance for modern automotive control applications. Sensors tend to be calibrated subsystems that are designed to stay in a defined tolerance and thus can easily be modeled. Compared to this deterministic behavior the transmission channel is time variant due to EMC and aging of contacts for example. The use of analog signaling, which is the actual state of realization in many cases, is sensitive to the time variant effects mentioned before. This time variance is hard to consider for the control system development. In this paper we will analyze the role of the sensor in the signal supply chain and discuss approaches for digital sensor-ECU communication and their potential to establish a link, which allows neglecting low level effects of the channel.

The paper will give an introduction to the principle of the giant magneto resistive - GMR - effect and the silicon system integration of GMR sensors. The two main applications of a GMR as a magnetic field strength sensor and as an angular field direction sensor will be discussed under consideration of automotive requirements. The typical applications of a magnetic field strength GMR sensor in incremental position and speed sensing and those of GMR angular field sensors in position sensing will be summarized. Finally advantages of GMR in those applications will be discussed and conclusions on the use of GMR in automotive sensing will be drawn.

In the case of a side impact the decision to deploy an airbag has to be taken much faster as it would be required for a front impact. Furthermore, there is a significant spread of the measurable acceleration depending on which pillars of the cars side are hit. Measuring the pressure inside the door as a direct result of an impact, the deformation of the door becomes observable. Based on pressure measurements side impacts can be detected much faster and more reliable. Therefore side airbag pressure sensors are established as add-on or replacement for side airbag acceleration sensors. This paper will present a Side Airbag Chip Set comprising of a side airbag pressure sensor and a satellite receiver. The system architecture and the partitioning between a single chip solution for the side airbag pressure sensor module plus the compatible satellite receiver will be described.

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.