STMicroelectronics' automotive sensor controls in-cabin acoustics

STMicroelectronics, a global semiconductor, is enabling more acoustically comfortable cars, with its new sensor for road-noise cancellation (RNC) through active noise-control (ANC) techniques. Vehicles have traditionally been defined by engine performance, exterior design, and powertrains, but drivers and passengers are increasingly focused on comfort.

While electric vehicles (EVs) are intrinsically less noisy than internal combustion engine cars (ICE), carmakers are focused on further lowering in-cabin noise due to wheel or vibration. These efforts aim to allow passengers to better enjoy the journey in a quieter ambient environment.

Noise cancellation algorithms, working with an array of sensors installed throughout the vehicle, measure the ambient sounds, and eliminate vibration using noise-cancelling waveforms that act as anti-vibration (cancelling) sounds.

“In today’s digital age, canceling, not deadening, unwanted sounds is the smart way to ensure a quieter cabin for safer, more enjoyable journeys,” said Simone Ferri, MEMS Sub-Group GM of Marketing, Analog, MEMS and Sensors Group, STMicroelectronics. “With the transition to hybrid and electric vehicles, which can be strongly affected by road noise, our AIS25BA accelerometer delivers superior value for system designers.”

ST has leveraged its competencies in micro-electro-mechanical system (MEMS) ICs to give the AIS25BA superior characteristics for enhancing RNC system accuracy. The sensor has the lowest electrical noise in the market, which helps vehicle engineers achieve the calmest possible in-car environment.

On the other hand, it has the fast response/low latency needed by the RNC system to calculate corrective waveforms in real-time as well as wide bandwidth to capture disturbances across the full spectrum of sound frequency relevant for the application. Its wide temperature range and mechanical robustness allows placement in the harshest places of today’s vehicles: near the engine or electric drive and close to wheels and suspension.