NewsSTMicroelectronics enables quieter cabins for the electric-vehicle age with advanced vibration sensor...

STMicroelectronics enables quieter cabins for the electric-vehicle age with advanced vibration sensor to eliminate road noise

Category articles

STMicroelectronics (NYSE STM) is a world-class semiconductor manufacturer that provides customers with the full spectrum of electronics will enable more acoustically acoustically conditioned cars thanks to its latest sensor for road noise cancellation (RNC) by using actively controlled noise (ANC) methods.

Cars are typically identified by their engine performance along with exterior design, as well as powertrains. However, people and drivers are becoming concerned with the comfort. While Electric Vehicles (EV) are inherently quieter than internal combustion engine vehicles (ICE) and car manufacturers are working to reduce the noise in the cabin due to the wheel or vibration. This will allow passengers to take pleasure in their journey in a more tranquil space. Noise cancellation algorithms, which work with a variety of sensors that are installed in the car, analyze the sounds in the surrounding area and block out vibrations using waves that can be used to cancel noise. They serve as anti-vibration (cancelling) noises. “In the age of digital blocking – not blocking out unwanted sound is the best way to have a quieter vehicle for safer, more enjoyable travel,” said Simone Ferri, MEMS Sub-Group General Manager of Marketing Analog MEMS and Sensors Group, STMicroelectronics. “With the shift to electric and hybrid vehicles that can be impacted by noise from the road the AIS25BA accelerometer offers an exceptional value to system designers.”

ST has applied its expertise in the field of micro-electro-mechanical system (MEMS) devices to provide the AIS25BA top-quality characteristics to improve RNC system precision. The sensor is the quietest electrical noise on the market which allows vehicle engineers to create the most peaceful possible car surroundings. However it offers the quick response and low latency required for it’s RNC software to compute the corrective waveforms in real time and also has a wide range of bandwidth to detect disruptions across the full range of frequencies that are relevant to the purpose. Its large temperature range and mechanical durability allow it to be placed in the most difficult locations in modern vehicles, such as close to the engine or the electric drive, as well as near suspensions and wheels. Additional technical details The AIS25BA 3-axis accelerometer from ST is engineered to give priority to RNC system precision. At 30ug/Hz for both axes X and Y and 50ug/Hz for the Z axis it has an extremely low noise density that can be up to 58% higher than the nearest competitor. With this exceptional quality of noise, the frequency response is extended to 2 and thus encompasses all spectrums that are important for noise cancellation in the car.

The total latency of the sensor, 266us, is designed to allow the system ample time to create noise-cancellation signals in real time. Furthermore it has an integrated time-division multiplex (TDM) digital interface. This allows the system to sync the outputs of multiple accelerometers to monitor the vibrations in the vehicle. This interface that is audio-friendly also permits an easy connection to other kinds of data busses that are widely used in the automotive industry. The full-scale measurement range can be customizable to +-7.7g providing ample space to the high-frequency vibrations that are that are typical for this kind of application. The range of supply voltage includes 1.71V from 1.99V. The AIS25BA is compatible with AEC-Q100 and available in 14-lead 2.5mm wide x 2.5mm and 0.86mm LGA package, priced starting at $3.90 for 1000 pieces.

Michal Pukala
Electronics and Telecommunications engineer with Electro-energetics Master degree graduation. Lightning designer experienced engineer. Currently working in IT industry.