MEMS acceleration sensor targets eCall and navigation
Until now, the automotive industry used the data generated by acceleration sensors in the first place for safety applications. The SMA130 – by the way the smallest acceleration sensor for automotive deployment – is designed for applications like eCall or navigation systems. The device measures acceleration in three orthogonal axes which translates into information regarding inclination, movement, vibration and shock. Series production of the sensor will start against the end of 2015.
Thanks to its small package of just 2- x 2-mm, the SMA130 can be integrated into the vehicle easily. Despite its small size it provides signals at a resolution of 14 bit; users can select either a range of ±2g and ±16g. Against the background of its small size, this high resolution poses significant demand to the sensor’s design. Nevertheless the device consumes only 130 µA in active state. In addition, five user-defined current-saving modes help reduce the power consumption to as low as 1 µA – a fact that is relevant for usage when the car is parked and the generator is off for longer periods. The individual power-saving modes can be activated in less than 2 milliseconds to make sure that the respective application quickly and reliably receives the relevant sensor information.
A digital interface allows users to select four measurement ranges individually and set a number of filter options. An integrated self-test facility ensures the reliability of the sensor signals. And yes, of course is the sensor qualified according to automotive standard AEC-Q100.
The sensor signals can be utilised for a wide range of applications. Besides vehicle acceleration data relevant for eCall or the alarm system, the SMA130 can support the navigation system during poor GPS signal reception. An example: If different lanes of a motorway are overlapping the sensor provides inclination data to the navigation system enabling it to precisely determine the vehicle’s position.