ST’s First Sensors From the Old NXP Business Are Aimed at Everyday Cars

STMicroelectronics has started production of four motion sensors for car safety systems. Each one combines a gyroscope and an accelerometer in a single chip. They are the first products to come out of the automotive and industrial MEMS sensor business ST bought from NXP earlier this year.

The sensors are meant for mainstream vehicles rather than premium models. ST lists the jobs they can do: crash protection, rollover detection, airbag deployment, stability control and keeping radar beams steady.

The four versions differ in which way they sense rotation and how much acceleration they can measure. Two read yaw, the turning motion around the vertical axis. The other two read roll, the side-to-side tilt. Three use a low-g accelerometer covering a nominal ±1.50 g to ±34 g. The fourth, the NCS1012EAEP, has a medium-g accelerometer rated from ±15.5 g to ±150 g, with its own signal chain to cut noise. The other part numbers are NCS1012BAEP, NCS1012CAEP and NCS10135AEP.

On the gyroscope side, buyers can choose ranges of ±125, ±250 or ±350 degrees per second. A built-in filter can be tuned from 12.5 Hz to 400 Hz.

Safety is crucially handled , the parts meet ISO 26262 and run full internal self-checks. They talk to the rest of the system over SafeSPI, which lets another controller check the sensor’s output on its own. The working temperature range is -40°C to +105°C.

It is a 24-pin QFN, 6 mm square and 1.90 mm high. Its wettable flanks let automated optical inspection check the solder joints after assembly. 

For Tier 1 suppliers, buying one combined part instead of two separate sensors is simpler. Having roll and yaw versions also means the sensor can be matched to the job, whether that’s spotting a rollover or keeping the car stable.