Acoustic activity detection is provided herein. Operations of a method can include receiving an acoustic signal at a micro-electromechanical system (MEMS) microphone. Based on portions of the acoustic signal being determined to exceed a threshold signal level, output pulses are generated. Further, the method can include extracting information representative of a frequency of the acoustic signal based on respective spacing between rising edges of the output pulses.

Acoustic activity detection is provided herein. Operations of a method can include receiving an acoustic signal at a micro-electromechanical system (MEMS) microphone. Based on portions of the acoustic signal being determined to exceed a threshold signal level, output pulses are generated. Further, the method can include extracting information representative of a frequency of the acoustic signal based on respective spacing between rising edges of the output pulses.

The present disclosure provides a microphone including at least one acoustoelectric transducer and an acoustic structure. The acoustoelectric transducer is configured to convert a sound signal to an electrical signal. The acoustic structure includes a sound guiding tube and an acoustic cavity. The acoustic cavity is in acoustic communication with the acoustoelectric transducer, and is in acoustic communication with outside of the microphone through the sound guiding tube. The acoustic structure has a first resonance frequency, the acoustoelectric transducer has a second resonance frequency, and an absolute value of a difference between the first resonance frequency and the second resonance frequency is not less than 100 Hz. By disposing different acoustic structures, resonance peaks in different frequency ranges may be added to the microphone, which improves a sensitivity of the microphone near multiple resonance peaks, thereby improving a sensitivity of the microphone in the entire wide frequency band.

The embodiments of the present disclosure may disclose a vibration sensor, including: an acoustic transducer and a vibration assembly connected with the acoustic transducer. The vibration assembly may be configured to transmit an external vibration signal to the acoustic transducer to generate an electric signal, the vibration assembly includes one or more groups of vibration diaphragms and mass blocks, and the mass blocks may be physically connected with the vibration diaphragms. The vibration assembly may be configured to make a sensitivity degree of the vibration sensor greater than a sensitivity degree of the acoustic transducer in one or more target frequency bands.

A MicroElectroMechanical System (MEMS) includes a MEMS device; a feature extraction component coupled to an output of the MEMS device, wherein the feature extraction component is configured to provide a plurality of features of an output signal of the MEMS device; and a low data rate interface coupled to the feature extraction components, wherein the low data rate interface is configured to transmit the plurality of features of the output signal of the MEMS device, and wherein a low data rate of the low data rate interface is determined by a number of the plurality of features transmitted, wherein the MEMS device, the feature extraction component, and the low data rate interface are packaged together in a semiconductor package.

A MicroElectroMechanical System (MEMS) includes a MEMS device; a feature extraction component coupled to an output of the MEMS device, wherein the feature extraction component is configured to provide a plurality of features of an output signal of the MEMS device; and a low data rate interface coupled to the feature extraction components, wherein the low data rate interface is configured to transmit the plurality of features of the output signal of the MEMS device, and wherein a low data rate of the low data rate interface is determined by a number of the plurality of features transmitted, wherein the MEMS device, the feature extraction component, and the low data rate interface are packaged together in a semiconductor package.

A method for forming a MEMS device includes following operations. A first semiconductor layer is formed over a substrate. A plurality of first pillars are formed over the first layer. A second layer is formed over the first pillars and the first layer. A plurality of second pillars are formed over the second layer. A third layer is formed over the second pillars and the second layer.

The present invention provides a microphone assembly having shielding function for a motor vehicle, comprising: a microphone circuit board having a microphone, which is supplied by a differential audio bus such that the ground potential of the microphone is floating; a cover which is located outside the microphone circuit board; a foamy part which is located between the cover and the microphone circuit board; and a shielding film which is suitable for shielding the microphone against electrostatic discharge, wherein the shielding film is located between the cover and the foamy part and covers the outer surface of the foamy part, and wherein the shielding film is electrically conductive and grounded to a vehicle chassis ground potential. In this situation, the shielding film can collect electrostatic charges and guide them to the chassis ground of the vehicle, so that electronic components on the microphone circuit board under the shielding film, especially the microphones having the floating ground, can be shielded from electrostatic discharge (ESD) damage. As a result, the ESD robust performance of the microphone assembly is significantly improved.

The present invention provides a microphone assembly having shielding function for a motor vehicle, comprising: a microphone circuit board having a microphone, which is supplied by a differential audio bus such that the ground potential of the microphone is floating; a cover which is located outside the microphone circuit board; a foamy part which is located between the cover and the microphone circuit board; and a shielding film which is suitable for shielding the microphone against electrostatic discharge, wherein the shielding film is located between the cover and the foamy part and covers the outer surface of the foamy part, and wherein the shielding film is electrically conductive and grounded to a vehicle chassis ground potential. In this situation, the shielding film can collect electrostatic charges and guide them to the chassis ground of the vehicle, so that electronic components on the microphone circuit board under the shielding film, especially the microphones having the floating ground, can be shielded from electrostatic discharge (ESD) damage. As a result, the ESD robust performance of the microphone assembly is significantly improved.

A segmented stator plate for an electrostatic transducer is provided. The segmented stator plate may have multiple electrically separate sections that can be independently operated and are usable to generate sound and/or detect sound waves in the electrostatic transducer.