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As software (SW) becomes more and more an important aspect of embedded system development, project schedules are requiring the earlier development of software simultaneously with hardware (HW). In addition, verification has increasingly challenged the design of complex mixed-signal SoC products. This is exacerbated for automotive safety critical SoC products with a high number of analogue interfaces (sensors and actuators) to the physical components such as an airbag SoC chipset. Generally, it is widely accepted that verification accounts for around 70% of the total SoC development. Since integration of HW and SW is the most crucial step in embedded system development, the sooner it is done, the sooner verification can begin. As such, any approaches which could allow verification and integration of HW/SW to be deployed earlier in the development process and help to decrease verification effort, (e.g.: accelerate verification runs) are of extreme interest.

Capacitive sensor technology has proven to be a reliable and robust measurement technology which is suitable for various sensing applications in the very demanding automotive environment. In this paper we present the design of a novel capacitive sensor for seat occupancy detection for next generation smart airbag systems. It is intended to provide information about the position of an occupant on the seat as well as dynamic changes thereof during an incident. This leads to the requirement of high sensitivity paired with a high measurement rate. In order to cope with these requirements a high frequency measurement principle is introduced. With higher frequencies and high signal strengths, the electromagnetic emissions of such a system may become a concern. Therefore, techniques for the reduction of such emission have to be applied. A prototype sensor system for seat occupancy detection has been realized.

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.

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.

More and more passenger cars are equipped with passive side protection systems such as thorax airbags for front and rear passengers. In the past, side airbag protection systems used sensors based on acceleration measurements [1]. In the meantime different sensor principles have been tested in order to increase the performance of this application. The intention has been to achieve faster firing decisions and to decrease the misuse risk for a floor or chassis impact. This paper presents the partitioning of an advanced chipset for pressure and acceleration based airbag systems. It shows the communication link between the sensors, the receiver-IC and other blocks in the application.