Knowles Electronics, Inc.

Audioasics A/s

Invensense, Inc.

Sonion A/s

Sonion Nederland B.v.

Sonion Tech A/s

Techtronic A/s

Epcos Pte Ltd

Claus Erdmann Fürst

Henrik Thomsen

Mohammad Shajaan

Kim Spetzler Berthelsen

Dibyendu Nandy

Per Flemming Høvesten

Venkataraman Chandrasekaran

Oddy Nopporn Khamharn

Anders Svava Mortensen

Aziz Yurttas

Jens Tingleff

Michael Deruginsky

John Szczech

Joshua Watson

Yang Li

Svetoslav Radoslavov Gueorguiev

Kristian Hansen

Igor Mucha

Mohammad Sadegh Mohammadi

John Nielsen

Lars Stenberg

Jens Jorgen Gaarde Henriksen

Aart Zeger Van Halteren

Michael Pedersen

Jens Kristian Poulsen

Sung Bok Lee

Michael Kuntzman

David Earl Schafer

Robert A Popper

Sarmad Qutub

Christian Lillelund

Mohsin Nawaz

Shubham Shubham

Jay Cech

Paul Fielding Smith

Jakob Kenn Toft

Tore Sejr Joergensen

Daifi Sassene

Lars J Stenberg

Aziz Yurrtas

Henrick Thomsen

Tomasz Marczak

Svetslav Gueorguiev

Oddy N Khamharn

The present disclosure relates to a transducer assembly including a transducer having a movable member, and a servo-loop controller configured to compensate for effects of a disturbance on the transducer assembly by adjusting a bias voltage applied to the transducer. A servo-loop controller having a smaller bandwidth for out-of-band disturbances than for in-band disturbances and configured to control the bias voltage based on a feedback signal generated by a sensor that detects an effect of the disturbance on the transducer assembly. The transducer assembly can be implemented as a microphone or a speaker among other sensors and actuators.

Microphone assembly with disturbance compensation

Microphones including a housing defining a cavity, a plurality of conductors positioned within the cavity, at least one dielectric bar positioned within the cavity, and a transducer diaphragm. The conductors are structured to move in response to pressure changes while the housing remains fixed. A first conductor generates first electrical signals responsive to the pressure changes resulting from changes in an atmospheric pressure. A second conductor generates second electrical signals responsive to the pressure changes resulting from acoustic activity. The dielectric bar is fixed with respect to the cavity and remains fixed under the pressure changes. The dielectric bar is adjacent to at least one of the conductors. In response to an applied pressure that is an atmospheric pressure and/or an acoustic pressure, the transducer diaphragm exerts a force on the housing and displaces at least a portion of conductors with respect to the dielectric bar.

Dielectric comb for MEMS device

An integrated circuit connectable to a sensor includes a transconductance element and a current-input analog-to-digital converter (I-ADC). The transconductance element is connectable to the sensor and is configured to generate a current signal representative of an output of the sensor. The I-ADC is configured to sample and quantize the current signal to generate a corresponding digital sensor signal. The I-ADC includes a continuous-time (CT) integrator stage, a discrete-time (DT) integrator stage, and a feedback digital-to-analog converter (FB-DAC). The CT integrator stage is configured to receive the current output and the I-ADC is configured to generate the digital sensor signal based on an output of the CT integrator stage and an output of the DT integrator stage. The FB-DAC is configured to provide a feedback signal based on the digital sensor signal for adding to the current signal.

Multi-rate integrated circuit connectable to a sensor

This disclosure provides methods, systems, and apparatuses, for a microphone circuit. In particular, the circuit includes transducer that can sense pressure changes and generate an electrical signal having frequency components in a first frequency range and in a second frequency range higher than the first frequency range. The circuit includes a feedback circuitry that can attenuate frequency components in the first frequency range in the electrical signal and, from it, generate an audio signal. A feedback path circuit includes a low pass filter having a cut-off frequency within the first frequency range, and filters the audio signal to generate a low pass filter signal that includes frequency components in the first frequency range. The low pass filter signal can be used to generate a low frequency pressure signal that corresponds to low frequency pressure changes sensed by the transducer.

Sensor device and microphone assembly

The present disclosure relates generally to digital microphone and other sensor assemblies including a transducer, a delta-sigma analog-to-digital converter (ADC), a dynamic element matching (DELM) entity configured to compensate for nonlinearity resulting from variation among digital-to-analog conversion (DAC) elements of the ADC, and a control circuit configured to enable and disable the DELM based on a magnitude of a digital signal generated by the ADC.

Digital sensor assembly with selective dynamic element matching

A microphone assembly includes a transducer element and a processing circuit. The processing circuit includes an analog-to-digital converter (ADC) configured to receive, sample and quantize a microphone signal generated by the transducer element to generate a corresponding digital microphone signal. The processing circuit includes a feedback path including a digital loop filter configured to receive and filter the digital microphone signal to provide a first digital feedback signal and a digital-to-analog converter (DAC) configured to convert the first digital feedback signal into a corresponding analog feedback signal. The processing circuit additionally includes a summing node at the transducer output configured to combine the microphone signal and the analog feedback signal.

Microphone assembly with digital feedback loop

A microphone assembly includes an acoustic filter with a first highpass cut-off frequency. The microphone assembly additionally includes a forward signal path and a feedback signal path. The forward signal path is configured to amplify or buffer an electrical signal generated by a transducer in response to sound and to convert the electrical signal to a digital signal. The feedback signal path is configured to generate a digital control signal based on the digital signal and to generate and output a sequence of variable current pulses based on the digital control signal. The variable current pulses suppress frequencies of the electrical signal below a second highpass cut-off frequency, higher than the first highpass cut-off frequency.

Digital microphone assembly with improved frequency response and noise characteristics

The present disclosure relates to an integrated circuit comprising a transconductance amplifier which is connectable to a microelectromechanical systems (MEMS) transducer. The transconductance amplifier comprises a first input coupled to a first current conveyor and a second input coupled to a second current conveyor for converting a single-ended or differential transducer signal voltage into an intermediate signal current representative of the transducer signal voltage through a shared reference resistor. The transconductance amplifier further comprises first and second output circuits coupled to the shared reference resistor and being configured to convert the intermediate current signal into a corresponding differential output current signal through first and second output terminals for driving a load.

Transconductance amplifier

A sensor signal processing circuit including a delta-sigma analog-to-digital converter (ADC) and a control circuit is disclosed. The circuit is configured to adaptively activate one or more segments of current elements for sequential sampling periods based on a digital signal input to a DAC, wherein less than N current elements are allocated to each segment, each current element in an active segment is enabled and either contributes to a feedback signal of the DAC or does not contribute to the feedback signal, and current elements not in an active segment are disabled. The circuit can be integrated with an acoustic or other sensor as part of a sensor assembly.

Sensor assembly and electrical circuit therefor

A system and method in an audio signal electrical circuit including a feedback loop with a digital filter coupled to a current digital to analog converter (IDAC) includes providing an output signal from the IDAC to analog elements of the audio signal electrical circuit, the output signal from the IDAC based upon a reference signal input to the IDAC when an output of the digital filter is not input to the IDAC. The system and method also include comparing an output signal of the audio signal electrical circuit to a reference, and calibrating the audio signal electrical circuit to correspond the output signal of the audio signal electrical circuit to the reference. Calibration of the audio signal electrical circuit enables more precise control of a cut-off frequency of a microphone signal when the output of the digital filter is input to the IDAC.

System and method for calibrating microphone cut-off frequency

The present disclosure relates generally to a microphone assembly. The microphone assembly has an acoustic activity detection mode of operation when the electrical circuit is clocked using an internal clock signal generator in the absence of an external clock signal at a host interface, and an electrical circuit of the microphone assembly is configured to provide an interrupt signal to the host interface upon detection of acoustic activity by the electrical circuit. The electrical circuit is configured to control the operating mode of the microphone assembly based on a frequency of the external clock signal in response to providing the interrupt signal and is configured to provide data representing the electrical signal to the host interface using the external clock signal received at the host interface.

Acoustic activity detecting microphone

A microelectromechanical system (MEMS) device includes at least one substrate, a lid, a MEMS component, a sensor, and a power supply. The lid is coupled to the substrate so that the substrate and the lid cooperatively define an interior cavity. The MEMS component is disposed within the interior cavity. The sensor is disposed within the interior cavity and is arranged to detect a parameter of the interior cavity. The power supply provides current to the sensor. The power supply is configured to control current during a ramp-up transition of the current and a ramp-down transition of the current such that the ramp-up transition and the ramp-down transition have attenuated high-frequency components.

Ramping of sensor power in a microelectromechanical system device

Systems and apparatuses for a microelectromechanical system (MEMS) device. The MEMS device includes a housing, a transducer, and a sensor. The housing includes a substrate defining a port and a cover. The substrate and the cover cooperatively form an internal cavity. The port fluidly couples the internal cavity to an external environment. The transducer is disposed within the internal cavity and positioned to receive acoustic energy through the port. The transducer is configured to convert the acoustic energy into an electrical signal. The sensor is disposed within the internal cavity and positioned to receive a gas through the port. The sensor is configured to facilitate detecting at least one of an offensive odor, smoke, a volatile organic compound, carbon monoxide, carbon dioxide, a nitrogen oxide, methane, and ozone.

Microphone with integrated gas sensor

A microphone assembly comprising: a housing including a base, a cover, and a sound port; a MEMS transducer element disposed in the housing, the transducer element configured to convert sound into a microphone signal voltage at a transducer output; and a processing circuit. The processing circuit comprising a transconductance amplifier comprising an input node connected to the transducer output for receipt of the microphone signal voltage, the transconductance amplifier being configured to generate an amplified current signal representative of the microphone signal voltage in accordance with a predetermined transconductance of the transconductance amplifier; and an analog-to-digital converter comprising an input node connected to receive the amplified current signal, said analog-to-digital converter being configured to sample and quantize the amplified current signal to generate a corresponding digital microphone signal.

Microphone assembly with reduced noise

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Roskilde, Denmark

Claus Erdmann Fürst