Abstract: A MEMS sensor system and method of operation is provided. The MEMS sensor system comprises a sensor device having a movable member and a sensor circuitry communicatively coupled the sensor device to at least one or more terminals. The sensor circuitry comprises a sensor ASIC and an analog signal processor coupled to least one of the sensor ASIC, the sensor device, and the terminal. The sensor ASIC is configured to operate either at a full performance mode after an audio signal is detected or at a lower power mode when the audio signal is not detected. A preamplifier coupled to the sensor device is configured to output a signal indicative of acoustic pressures on the movable member is provided. The sensor circuitry further comprises a sigma-delta modulator communicatively coupled to the preamplifier. When a target audio signal is detected by the analog signal processor, a control signal is sent to the sensor ASIC to set the preamplifer to full performance mode and to power on the sigma-delta converter.

Abstract: A digital microphone with a dynamic gain scaling system is provided. An ASIC coupled the microphone to the scaling system. An input buffer, a preamplifier, a pair of switching element, a bias source, and a capacitor coupled to the pair of switching element is integrated into the ASIC. In one embodiment, the scaling system is integrated into the ASIC. In another embodiment, the scaling system is a second ASIC and is coupled to the ASIC. The scaling system includes a ADC, a PDM, and a delta-sigma based BR filter and is configured to dynamically adjust various parameters of the ADC, preamplifier, and the bias source.

Abstract: A biasing circuit for a capacitive sensor includes a capacitive sensor element configured to produce a sensor voltage at a sense node, and a preamplifier connected to the sense node and configured to amplify the sensor voltage. The biasing circuit has an auxiliary amplifier connected between an output of the preamplifier and the sense node and configured to set a DC component of an input voltage for the preamplifier to a ratiometric DC bias voltage.

Abstract: A biasing circuit for a capacitive sensor includes a capacitive sensor element configured to produce a sensor voltage at a sense node, and a preamplifier connected to the sense node and configured to amplify the sensor voltage. The biasing circuit has an auxiliary amplifier connected between an output of the preamplifier and the sense node and configured to set a DC component of an input voltage for the preamplifier to a ratiometric DC bias voltage.

Abstract: A bi-directional charge pump cell includes a p-type substrate having a main surface. A first n-well is formed in the p-type substrate that includes n+ doped regions formed in the first n? well at the main surface. A first p-well is formed in the first n? well that includes p+ doped regions formed in the first p-well at the main surface. A second n-well is formed in the first p-well that includes n+ doped regions and PMOS transistors formed at the main surface. A second p-well is formed in the first n-well that includes p+ doped regions at the main surface. A third p-well is defined in the second p-well that includes p+ doped regions and NMOS transistors at the main surface.

Abstract: A method of detecting defects in a high impedance network of a MEMs microphone sensor interface circuit. The method includes adding a high-voltage reset switch to a high-voltage high impedance network, closing the high-voltage reset switch during a start-up phase of the MEMs microphone sensor interface circuit, simultaneously closing a low-voltage reset switch of a low-voltage high impedance network during the start-up phase, simultaneously opening the high-voltage reset switch and the low-voltage reset switch at the end of the start-up phase, and detecting a defect in the high-voltage high impedance network or the low-voltage high impedance network immediately after opening the high-voltage reset switch and the low-voltage reset switch.

Abstract: A method of detecting defects in a high impedance network of a MEMs microphone sensor interface circuit. The method includes adding a high-voltage reset switch to a high-voltage high impedance network, closing the high-voltage reset switch during a start-up phase of the MEMs microphone sensor interface circuit, simultaneously closing a low-voltage reset switch of a low-voltage high impedance network during the start-up phase, simultaneously opening the high-voltage reset switch and the low-voltage reset switch at the end of the start-up phase, and detecting a defect in the high-voltage high impedance network or the low-voltage high impedance network immediately after opening the high-voltage reset switch and the low-voltage reset switch.

Abstract: Systems and methods of generating independent adjustable bias voltages for a differential microphone. The microphone system includes a positive adjustable charge pump, a positive sense capacitor, a negative adjustable charge pump, a negative sense-capacitor, and a differential amplifier. The positive adjustable charge pump is configured to generate a positive bias voltage. The positive sense-capacitor is configured to generate a positive sense voltage based on acoustic pressure from a first direction and the positive bias voltage. The negative adjustable charge pump is configured to generate a negative bias voltage. The negative sense-capacitor is configured to generate a negative sense voltage based on the acoustic pressure from the first direction and the negative bias voltage. The differential amplifier is configured to receive the positive and negative sense voltages. The differential amplifier is also configured to generate a differential voltage based on the positive and negative sense voltages.

Abstract: Systems and methods of generating independent adjustable bias voltages for a differential microphone. The microphone system includes a positive adjustable charge pump, a positive sense capacitor, a negative adjustable charge pump, a negative sense-capacitor, and a differential amplifier. The positive adjustable charge pump is configured to generate a positive bias voltage. The positive sense-capacitor is configured to generate a positive sense voltage based on acoustic pressure from a first direction and the positive bias voltage. The negative adjustable charge pump is configured to generate a negative bias voltage. The negative sense-capacitor is configured to generate a negative sense voltage based on the acoustic pressure from the first direction and the negative bias voltage. The differential amplifier is configured to receive the positive and negative sense voltages. The differential amplifier is also configured to generate a differential voltage based on the positive and negative sense voltages.

Abstract: Systems and methods of generating independent adjustable bias voltages for a differential microphone. The microphone system includes a positive adjustable charge pump, a positive sense capacitor, a negative adjustable charge pump, a negative sense-capacitor, and a differential amplifier. The positive adjustable charge pump is configured to generate a positive bias voltage. The positive sense-capacitor is configured to generate a positive sense voltage based on acoustic pressure from a first direction and the positive bias voltage. The negative adjustable charge pump is configured to generate a negative bias voltage. The negative sense-capacitor is configured to generate a negative sense voltage based on the acoustic pressure from the first direction and the negative bias voltage. The differential amplifier is configured to receive the positive and negative sense voltages. The differential amplifier is also configured to generate a differential voltage based on the positive and negative sense voltages.

Abstract: An adjustable charge pump system. The system includes a voltage regulator, a clock circuit, a voltage adjustment circuit, and a charge pump. The voltage regulator is configured to receive an input voltage and output a regulated voltage. The clock circuit is coupled to the voltage regulator and receives the regulated voltage. The voltage adjustment circuit is coupled to the voltage regulator and is configured to receive the regulated voltage and to output a driver voltage. The charge pump includes a plurality of stages. The output of the adjustable charge pump system is adjusted by disabling one or more stages of the first stage and the plurality of subsequent stages.

Abstract: A method of detecting defects in a high impedance network of a MEMs microphone sensor interface circuit. The method includes adding a high-voltage reset switch to a high-voltage high impedance network, closing the high-voltage reset switch during a start-up phase of the MEMs microphone sensor interface circuit, simultaneously closing a low-voltage reset switch of a low-voltage high impedance network during the start-up phase, simultaneously opening the high-voltage reset switch and the low-voltage reset switch at the end of the start-up phase, and detecting a defect in the high-voltage high impedance network or the low-voltage high impedance network immediately after opening the high-voltage reset switch and the low-voltage reset switch.

Abstract: A method of initiating a reset sequence for a MEMS capacitive microphone. The method includes monitoring an output of a microphone and detecting a mute condition in the output of the microphone indicative of a fault condition. The method also includes activating a timing circuit. The timing circuit is configured to indicate when a certain time period since the initiation of the timing circuit has elapsed. Upon expiration of the time period indicated by the timing circuit, a microphone reset sequence is initiated.

Abstract: An adjustable charge pump system. The system includes a voltage regulator, a clock circuit, a voltage adjustment circuit, and a charge pump. The voltage regulator is configured to receive an input voltage and output a regulated voltage. The clock circuit is coupled to the voltage regulator and receives the regulated voltage. The voltage adjustment circuit is coupled to the voltage regulator and is configured to receive the regulated voltage and to output a driver voltage. The charge pump includes a plurality of stages. The output of the adjustable charge pump system is adjusted by disabling one or more stages of the first stage and the plurality of subsequent stages.

Abstract: A method of initiating a reset sequence for a MEMS capacitive microphone. The method includes monitoring an output of a microphone and detecting a mute condition in the output of the microphone indicative of a fault condition. The method also includes activating a timing circuit. The timing circuit is configured to indicate when a certain time period since the initiation of the timing circuit has elapsed. Upon expiration of the time period indicated by the timing circuit, a microphone reset sequence is initiated.

Abstract: The MEMS switch has a high-impedance state and a low-impedance state for biasing a capacitive sensor, and includes an actuation bias terminal, a sense bias terminal, a switch control terminal, a sense node terminal, and a spring. The actuation bias terminal and the sense bias terminal reside in a released region of the switch. The sense bias terminal is physically coupled to the actuation bias terminal by a dielectric which electrically isolates the sense bias terminal from the actuation bias terminal. The switch control terminal is separated from the sense bias terminal by a first air gap, and the sense node terminal is separated from the sense bias terminal by a second air gap. The spring supports the actuation bias terminal, the sense bias terminal, and the dielectric.

Abstract: A MEMS switch. The MEMS switch has a high-impedance state and a low-impedance state for biasing a capacitive sensor, and includes an actuation bias terminal, a sense bias terminal, a switch control terminal, a sense node terminal, and a spring. The actuation bias terminal and the sense bias terminal reside in a released region of the switch. The sense bias terminal is physically coupled to the actuation bias terminal by a dielectric which electrically isolates the sense bias terminal from the actuation bias terminal. The switch control terminal is separated from the sense bias terminal by a first air gap, and the sense node terminal is separated from the sense bias terminal by a second air gap. The spring supports the actuation bias terminal, the sense bias terminal, and the dielectric.

Abstract: Provided is a micro-electromechanical-system (MEMS) device including a substrate; at least one semiconductor layer provided on the substrate; a circuit region including at least one chip containing drive/sense circuitry, the circuit region provided on the at least one semiconductor layer; a support structure attached to the substrate; at least one elastic device attached to the support structure; a proof-mass suspended by the at least one elastic device and free to move in at least one of the x-, y-, and z-directions; at least one top electrode provided on the at least one elastic device; and at least one bottom electrode located beneath the at least one elastic device such that an initial capacitance is generated between the at least one top and bottom electrodes, wherein the drive/sense circuitry, proof-mass, supporting structure, and the at least one top and bottom electrodes are fabricated on the at least one semiconductor layer.

Abstract: An integrated circuit device includes a semiconductor die, the semiconductor die including a semiconductor substrate, driving/control circuitry disposed along a peripheral region of the semiconductor die, a MEMS device disposed within a central region of the semiconductor die, and a barrier disposed between the driving/control circuitry and the MEMS device.

Abstract: Provided is a micro-electromechanical-system (MEMS) device including a substrate; at least one semiconductor layer provided on the substrate; a circuit region including at least one chip containing drive/sense circuitry, the circuit region provided on the at least one semiconductor layer; a support structure attached to the substrate; at least one elastic device attached to the support structure; a proof-mass suspended by the at least one elastic device and free to move in at least one of the x-, y-, and z-directions; at least one top electrode provided on the at least one elastic device; and at least one bottom electrode located beneath the at least one elastic device such that an initial capacitance is generated between the at least one top and bottom electrodes, wherein the drive/sense circuitry, proof-mass, supporting structure, and the at least one top and bottom electrodes are fabricated on the at least one semiconductor layer.