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For side airbag systems it is necessary to measure the acceleration within a time of less than 3 ms in order to inflate the side airbag in time. A new generation of side airbag sensors that uses a linear accelerometer is presented. The evaluation circuit includes amplification, temperature coefficient compensation, two wire unidirectional current interface, and a zero-offset compensation. The sensing element for the measurement of acceleration is a surface micromachined accelerometer. In order to minimise the production costs the surface micromachined sensor element and the corresponding evaluation ASIC are packaged into a standard PLCC28 housing. For the entire function only few external components are necessary. During the power-on cycle an internal selftest is carried out and the result is transmitted to the airbag control unit. Most important results of the characterisation are presented.

This paper reports on a new generation of silicon gyroscopes, which can be used as angular rate sensors for roll-over sensing or navigation control. The sensor is fabricated in standard Si-surface micromachining technology and encapsulated under vacuum conditions using an Si-micromachined cap wafer. The sensor consists of an electrostatically driven oscillating disk, which reacts with a tilt movement when an angular rate is applied due to the conservation law for angular momentums. The tilt movement is then detected capacitively by electrodes on the substrate underneath the oscillating disk. The sensor is packaged in a standard SMD housing (PLCC44).