Knowles Electronics, Inc.

Epcos Pte Ltd

Per Flemming Høvesten

Claus Erdmann Fürst

Henrik Thomsen

Mohammad Shajaan

Kim Spetzler Berthelsen

Gino Rocca

Jens Kristian Poulsen

Leif Steen Johansen

Svetoslav Radoslavov Gueorguiev

Lars Jørn Stenberg

Allan Nielsen

Aziz Yurrtas

Emil Jakobsen

The disclosure relates to microphone and other sensor assemblies having a transduction element and an integrated circuit. The integrated circuit includes a switched-capacitor delta-sigma analog-to-digital converter (ADC) including a first integrator stage having a switched-capacitor circuit and a first plurality of parallel amplifiers. A logic circuit coupled to the integrator circuit is configured to selectably disable a subset of enabled amplifiers of the first integrator stage during a first phase of operation and to re-enable the subset of disabled amplifiers during a second phase.

Digital sensors, electrical circuits and methods

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

A microphone assembly includes a transducer and a processing circuit. The processing circuit includes an analog-to-digital converter (ADC) configured to receive, sample and quantize an electrical signal generated by the transducer to generate a corresponding digital signal. The processing circuit includes a feedback path including a digital loop filter configured to receive and filter the digital 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 configured to combine the electrical signal and the analog feedback signal.

A microphone assembly includes an acoustic transducer element configured to convert sound into a microphone signal in accordance with a transducer frequency response including a first highpass cut-off frequency. The microphone assembly additionally includes a processing circuit including a signal amplification path configured to receive, sample and digitize the microphone signal to provide a digital microphone signal. A frequency response of the signal amplification path includes a second highpass cut-off frequency which is higher than the first highpass cut-off frequency of the acoustic transducer element.

Approaches are provided for an apparatus that includes an input buffer, an analog-to-digital converter coupled to the input buffer, a decompress module coupled to the analog to digital converter, and a gain control module coupled to the input buffer and the decompress module. The input buffer has a first adjustable gain and operating in the analog domain. The analog-to-digital converter converts the input analog data received from the input buffer into digital data. The decompress module operates in the digital domain, and is configured to decompress the digital data received from the analog-to-digital converter. The decompress module has a second adjustable gain and produces an output digital signal. The gain control module determines when to compensate for changes in characteristics the input analog data by selectively controlling the first gain of the input buffer in the analog domain and the second gain of the decompress module in the digital domain.

Digital microphone with adjustable gain control

The present invention relates to a condenser microphone assembly comprising an electro-acoustic transducer element comprising a diaphragm and a back plate, signal processing circuitry operatively connected to the transducer element so as to process signals generated by the transducer element, and a mode-setting circuitry for selectively setting the condenser microphone assembly in a test mode or an operational mode. The electro-acoustic sensitivity of the condenser microphone assembly, when operated in the test mode, is at least 40 dB lower than the corresponding electro-acoustic sensitivity of the assembly when operated in the operational mode. The present invention further relates to a method for determining a performance parameter of a signal processing circuitry mounted inside a housing of an assembled condenser microphone assembly.

Microphone assembly with integrated self-test circuitry

The present invention relates to a miniature microphone assembly comprising a capacitive microphone transducer comprising a microphone electrical contact or terminal, a microphone carrier comprising a carrier electrical contact or terminal formed on a first surface thereof, and an integrated circuit die comprising a die electrical terminal operatively coupled to signal amplification or signal conditioning circuitry of the integrated circuit die. The first surface of the microphone carrier comprises a first electrically conductive path surrounding the carrier electrical contact or terminal.

Miniature microphone assembly with solder sealing ring

The present invention relates to a condenser microphone assembly comprising a condenser microphone transducer comprising adjacently positioned diaphragm and back-plate members having an air gap there between. Moreover, the assembly comprises a deep sub-micron MOS integrated circuit die comprising a preamplifier comprising a first signal input terminal for receipt of electrical signals generated by the condenser microphone transducer. The first signal input terminal is operatively coupled to an input stage of the preamplifier, said input stage comprising a thick-oxide transistor. The present invention further relates to a deep sub-micron MOS integrated circuit die comprising a thick-oxide transistor-based preamplifier.

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Måløv, Denmark

Per Flemming Høvesten