Abstract: In accordance with an embodiment, a digital microphone interface circuit includes a delta-sigma analog-to-digital converter (ADC) having an input configured to be coupled to a microphone, a digital lowpass filter coupled to an output of the delta-sigma ADC, and a digital sigma-delta modulator coupled to an output of the digital lowpass filter. The delta-sigma ADC, the digital lowpass filter, and the digital sigma-delta modulator are configured to operate at different sampling frequencies.

Abstract: In accordance with an embodiment, a method includes adding a dither signal to a first signal to generate a second signal, subtracting the dither signal from the first signal or subtracting the first signal from the dither signal to generate a third signal, performing a first sigma delta conversion of the second signal to a digital fourth signal, performing a second signal delta conversion of the third signal to a digital fifth signal, combining the digital fourth signal and the digital fifth signal to form a digital sixth signal.

Abstract: In various embodiments, a circuit arrangement includes a calibration filter set up to receive a signal based on a first signal and to provide a calibrated signal, the first signal being a signal which is provided by an analog/digital converter and is based on an analog signal, the analog signal being provided by at least one sensor of a sensor arrangement, a filter arrangement set up to receive a signal based on the first signal and to provide a second signal, and a controller set up to select a sensor-specific control signal dependent on the frequency response of the sensor from a plurality of control signals and to provide the calibration filter with said signal, the calibrated signal being based on the first signal and the sensor-specific control signal and corresponding or substantially corresponding to a predefined spectral mask in a predefined frequency range.

Abstract: A Micro-Electro-Mechanical System (MEMS) circuit and a method for reconstructing an interference variable are provided. The MEMS circuit includes a MEMS device configured to generate a MEMS signal; a control circuit configured to detect a switched-on state or switched-off state of at least one device and configured to generate a control signal at least partly depending on the switched-on state or the switched-off state; a reconstruction filter configured to determine an interference signal that is partly generated by the at least one device, using the generated control signal; and a subtractor configured to subtract the determined interference signal from the MEMS signal.

Abstract: A sensor circuit and a method for compensating for temperature changes are provided. In accordance with an embodiment, sensor circuit includes at least one sensor for determining a measurement variable; a heating structure; and at least one compensation circuit. The compensation circuit is configured to acquire information about a temperature change in an environment of the sensor, and to counteract a temperature change in the sensor on the basis of the information by driving the heating structure.

Abstract: In various embodiments, a circuit arrangement is provided. The circuit arrangement includes a sensor set up to provide an analogue signal, an analogue/digital converter set up to receive the analogue signal and to provide a first signal, and a first filter set up to receive a signal based on the first signal and to provide a second signal. The first filter is set up in such a manner that the second signal is allowed through without amplification or substantially without amplification in a frequency range of approximately 20 Hz to approximately 10 kHz, and the second signal has a gain of greater than 0 dB at least above a predefined frequency which is greater than approximately 20 kHz.

Abstract: According to an embodiment, a method of operating an acoustic device includes buffering, by a buffer circuit, a first electrical signal from an acoustic transducer to produce a second electrical signal, receiving a feedback signal at a supply circuit, and comparing the feedback signal to a first threshold. The feedback signal is based on the first electrical signal. The method further includes, based on comparing the feedback signal to the first threshold, switching between a first mode and a second mode, supplying a first supply voltage to the buffer circuit during the first mode, and supplying a second supply voltage to the buffer circuit during the second mode. The first supply voltage is different from the second supply voltage.

Abstract: According to an embodiment, a sensor circuit includes a sigma-delta analog to digital converter (ADC), a dithered clock coupled to the sigma-delta ADC, and a supply voltage circuit coupled to the sigma-delta ADC. The sigma-delta ADC is configured to be coupled to a low frequency transducer, and the dithered clock is configured to control of the sigma-delta ADC based on a dithered clock signal.

Abstract: In some embodiments, a microphone system includes a multi-bit delta-sigma modulator configured to be coupled to a microphone and configured to covert an output of the microphone into a first digital signal with a multi-bit resolution at a first output of the multi-bit delta-sigma modulator. The microphone system also includes a digital noise shaper coupled to the first output of the multi-bit delta-sigma modulator, and configured to convert a multi-bit digital input of the digital noise shaper into a one-bit digital signal.

Abstract: An apparatus (100) comprises a signal generator (101) that is set up to produce a digital random signal (191). The apparatus (100) also comprises at least one filter element (102, 121, 122) that is set up to apply a high pass filter and a low pass filter to the digital random signal (191) in order to produce a spectrally shaped random signal (112). The apparatus (100) also comprises a modulator (103) that is set up to apply the spectrally shaped random signal (192) as dither.

Abstract: In various embodiments, a circuit arrangement includes a calibration filter set up to receive a signal based on a first signal and to provide a calibrated signal, the first signal being a signal which is provided by an analog/digital converter and is based on an analog signal, the analog signal being provided by at least one sensor of a sensor arrangement, a filter arrangement set up to receive a signal based on the first signal and to provide a second signal, and a controller set up to select a sensor-specific control signal dependent on the frequency response of the sensor from a plurality of control signals and to provide the calibration filter with said signal, the calibrated signal being based on the first signal and the sensor-specific control signal and corresponding or substantially corresponding to a predefined spectral mask in a predefined frequency range.

Abstract: In some embodiments, a microphone system includes a multi-bit delta-sigma modulator configured to be coupled to a microphone and configured to covert an output of the microphone into a first digital signal with a multi-bit resolution at a first output of the multi-bit delta-sigma modulator. The microphone system also includes a digital noise shaper coupled to the first output of the multi-bit delta-sigma modulator, and configured to convert a multi-bit digital input of the digital noise shaper into a one-bit digital signal.

Abstract: In various embodiments, a circuit arrangement is provided. The circuit arrangement includes a sensor set up to provide an analogue signal, an analogue/digital converter set up to receive the analogue signal and to provide a first signal, and a first filter set up to receive a signal based on the first signal and to provide a second signal. The first filter is set up in such a manner that the second signal is allowed through without amplification or substantially without amplification in a frequency range of approximately 20 Hz to approximately 10 kHz, and the second signal has a gain of greater than 0 dB at least above a predefined frequency which is greater than approximately 20 kHz.

Abstract: An apparatus (100) comprises a signal generator (101) that is set up to produce a digital random signal (191). The apparatus (100) also comprises at least one filter element (102, 121, 122) that is set up to apply a high pass filter and a low pass filter to the digital random signal (191) in order to produce a spectrally shaped random signal (112). The apparatus (100) also comprises a modulator (103) that is set up to apply the spectrally shaped random signal (192) as dither.

Abstract: An analog-to-digital converter arrangement may include an analog amplifier with variable gain; an analog-to-digital converter; a digital reconstruction element including elements to reduce an influence of transients during a change of the variable gain of the analog amplifier.

Abstract: According to an embodiment, a method of operating an acoustic device includes buffering, by a buffer circuit, a first electrical signal from an acoustic transducer to produce a second electrical signal, receiving a feedback signal at a supply circuit, and comparing the feedback signal to a first threshold. The feedback signal is based on the first electrical signal. The method further includes, based on comparing the feedback signal to the first threshold, switching between a first mode and a second mode, supplying a first supply voltage to the buffer circuit during the first mode, and supplying a second supply voltage to the buffer circuit during the second mode. The first supply voltage is different from the second supply voltage.

Abstract: A pseudorandom binary sequence having a first sampling rate is generated. Based on the pseudorandom binary sequence, a digital filter generates a spectrally shaped pseudorandom binary sequence having a second sampling rate. The second sampling rate is equal to the first sampling rate multiplied by an integer upsampling factor of L>1. The digital filter includes L filter branches consisting of a first subset of one or more filter branches and a second subset of one or more filter branches. Each filter branch of the first subset generates a binary output which is equal to an input of the filter branch. Each filter branch of the second subset generates a binary output which is inverted with respect to an input of the filter branch.

Abstract: A digitized system operates to receive one or more analog signals from a sensor or other component and convert the analog signals to one or more digital signals. An analog-to-digital converter comprises a loop filter, a quantizer and one or more feedback digital-to-analog converters. A gain component provides coefficients along different points of a signal processing path to extend a bandwidth of the analog-to-digital converter. The gain component can modify a signal transfer function of the analog-to-digital converter while preserving a noise transfer function in order to process a signal in a higher frequency band in an extended mode of operation than other signals being processed in a normal operating mode.

Abstract: According to an embodiment, a sensor circuit includes a sigma-delta analog to digital converter (ADC), a dithered clock coupled to the sigma-delta ADC, and a supply voltage circuit coupled to the sigma-delta ADC. The sigma-delta ADC is configured to be coupled to a low frequency transducer, and the dithered clock is configured to control of the sigma-delta ADC based on a dithered clock signal.

Abstract: A nonlinear converter, such as a DC-DC converter, includes a nonlinear controller configured to receive an output voltage and a current, and configured to generate a PWM signal. The PWM signal is generated based on setting the converter to a first phase associated with both buck and boost modes when a clock signal is asserted, and selecting a second phase associated with the buck mode of the converter, if a sliding function signal achieves a first predetermined relationship with respect to a buck threshold before a next clock signal is asserted, or selecting a third phase associated with the boost mode of the converter, if the sliding function signal achieves a second predetermined relationship with respect to a boost threshold before a next clock signal is asserted. The nonlinear converter may include a power stage configured to provide the output voltage and a coil current to the nonlinear controller.