Circuit configuration for the passenger protection device of a vehicle

Abstract

A circuit configuration for a passenger protection device, such as an airbag, includes at least first and second collision sensors having triggering thresholds individually assigned thereto, for triggering a passenger protection device if the collision sensors exceed the triggering thresholds. The first sensor supplies an output signal exceeding the triggering threshold assigned to it before the second sensor issues an output signal exceeding the triggering threshold assigned to it, in the event of a collision. One of the sensors is a clock-generating sensor setting a beginning of a time period when its output signal exceeds a threshold value assigned to it, during the collision. One of the sensors mechanically actuates a switch and supplies an essentially binary output signal, in the event of a collision. Both of the sensors are required to exceed their triggering thresholds no later than a point in time within the time period, for the protection system to be finally triggered. The other of the sensors is an electronic sensor, such as a piezoresistive or a piezoelectric sensor, supplying an analog output signal, in the event of a collision. A programmable read-only memory PROM records a collision occurrence and stores data regarding a behavior of the output signals of at least one of the sensors occurring during the time period, at least if both of the sensors had exceeded their triggering thresholds during the point in time.