SMA6xy’s standardized housing makes design-in more straightforward
- Greatly improved protection against microcuts
- Increased design freedom thanks to flexible orientation
- For use in ASIL D airbag systems in accordance with ISO 26262
Bosch’s latest generation of acceleration sensors makes developing airbag systems easier. With versions for use in the airbag control unit and versions for peripheral use in the vehicle’s front, sides, and rear, the SMA6xy sensor platform simplifies the release approval process by giving sensors a common housing design whatever the application. All the sensors in the new SMA6xy product family are ideally suited to Bosch ASICs for airbag systems.
Better protection against microcuts
The PSI5 sensor for peripheral use comes in versions offering measurement ranges of 120, 240, or 480 g (type SMA68x and SMA69x). In addition to the normal x and y channels, these sensors are now also available with a z channel for measuring acceleration in the vertical axis. So whatever the desired orientation of the sensor’s installation, there is a version to match. This gives airbag system developers greater design freedom. Compared to previous versions, the new sensors are much better protected against microcuts – extremely brief interruptions in power supply to the sensor following an impact – and can now tolerate interruptions of up to 10 microseconds.
Designed to be installed in the airbag control unit, the SPI sensors can measure accelerations of up to 120 g (type SMA66x) and their readings have 12-bit resolution. An arming pin helps developers to initiate the airbag algorithm by showing when readings exceed a defined threshold value.
All sensors in the SMA6xy product family have a compact SOIC8n housing and are available in 1-channel (x, y or z axis) or 2-channel (x-y or y-z axes) versions. Since they are designed for use in safety-critical airbag systems, the sensors meet the criteria stipulated for the ASIL D safety level in accordance with ISO 26262.
Samples of the SMA6xy are already available.
Background to MEMS technology
Bosch has been at the forefront of MEMS (microelectromechanical systems) technology since the very beginning. Since the start of production in 1995, the company has manufactured well in excess of three billion MEMS sensors, with production volumes hitting new highs year after year. In 2013, more than a billion sensors rolled off the production lines at the company’s Reutlingen plant. The range includes sensors for measuring pressure, acceleration, humidity, temperature, yaw rate, inertia, and geomagnetic field, as well as MEMS microphones for a wide range of applications in the consumer electronics and automotive industries. More information on Bosch sensors is available online at www.bosch-sensors.com.
