Abstract: An acoustic sensor device includes a substrate, a cavity formed in the substrate, and a microelectromechanical system (MEMS) transducer having a diaphragm supported by the substrate. The diaphragm includes a first portion configured to be fixed to the substrate and a second portion extending from the first portion and suspended over the cavity. The second portion is configured to vibrate when the MEMS transducer is subject to an external stimulus. The diaphragm also includes an anchor portion that attaches the first portion of the diaphragm to the substrate on at least two sides of the substrate such that an interface between the first portion of the diaphragm and the second portion of the diaphragm is moved away from an edge of the substrate along the cavity.

Abstract: An electrostatic transducer includes a substrate oriented in a plane, a fixed electrode supported by the substrate, and a moveable electrode supported by the substrate, spaced from the fixed electrode in a first direction parallel to the plane, and configured for movement in a second direction transverse to the plane, such that an extent to which the fixed and moveable electrodes overlap changes during the movement. The fixed and moveable electrodes comprise one or more of a plurality of conductive layers, the plurality of conductive layers including at least three layers. The fixed electrode includes a stacked arrangement of two or more spaced apart conductive layers of the plurality of conductive layers.

Abstract: A microelectromechanical (MEMS) transducer includes a substrate, a moveable electrode supported by the substrate, and a pair of fixed electrodes supported by the substrate, each fixed electrode of the pair of fixed electrodes being configured as a bias or sense electrode. The pair of fixed electrodes are disposed in a stacked arrangement. An end of the moveable electrode is configured for vibrational movement along the stacked arrangement during excitation of the moveable electrode. The pair of fixed electrodes are laterally spaced apart from the end of the moveable electrode to establish a capacitance indicative of the vibrational movement.

Abstract: A microelectromechanical system (MEMS) transducer includes a substrate and a pair of electrodes supported by the substrate. The pair of electrodes are configured as a bias electrode-sense electrode couple. A moveable electrode of the pair of electrodes is configured for vibrational movement in a first direction during excitation of the moveable electrode. The pair of electrodes are spaced apart from one another by a gap in a second direction perpendicular to the first direction. The moveable electrode includes a cantilevered end, the cantilevered end being warped to exhibit a resting deflection along the first direction.

Abstract: An acoustic sensor device comprises a package and a substrate disposed in the package. The acoustic sensor device also comprises a microelectromechanical system (MEMS) transducer formed in the substrate, the MEMS transducer i) comprising a cantilever structure and ii) having a first acoustic impedance and at least two sound ports positioned on the package on opposing sides of the MEMS transducer. The at least two sound ports coupling the MEMS transducer to an ambient environment via respective acoustic channels formed in the package, wherein the at least two sound ports are positioned on the package in a manner that ensures that the respective acoustic channels have a combined second acoustic impendence that is less the first acoustic impedance of the MEMS transducer.

Abstract: A microelectromechanical system (MEMS) transducer includes a substrate and a pair of electrodes supported by the substrate. The pair of electrodes are configured as a bias electrode-sense electrode couple. A moveable electrode of the pair of electrodes is configured for vibrational movement in a first direction during excitation of the moveable electrode. The pair of electrodes are spaced apart from one another by a gap in a second direction perpendicular to the first direction. The moveable electrode includes a cantilevered end, the cantilevered end being warped to exhibit a resting deflection along the first direction.

Abstract: A device includes a housing, an acoustic sensor disposed within the housing, the acoustic sensor comprising a microelectrornechanical (MEMS) transducer, a first port in the housing establishing a first acoustic path for air flow to the MEMS transducer, and a second port in the housing establishing a second acoustic path for air flow to the MEMS transducer. The first and second acoustic paths have an equal path length.

Abstract: A microelectromechanical system (MEMS) transducer includes a substrate and a pair of electrodes supported by the substrate. The pair of electrodes are configured as a bias electrode-sense electrode couple. A moveable electrode of the pair of electrodes is configured for vibrational movement in a first direction during excitation of the moveable electrode. The pair of electrodes are spaced apart from one another by a gap in a second direction perpendicular to the first direction. The moveable electrode includes a cantilevered end, the cantilevered end being warped to exhibit a resting deflection along the first direction.

Abstract: An electrostatic transducer includes a substrate oriented in a plane, a fixed electrode supported by the substrate, and a moveable electrode supported by the substrate, spaced from the fixed electrode in a first direction parallel to the plane, and configured for movement in a second direction transverse to the plane, such that an extent to which the fixed and moveable electrodes overlap changes during the movement. The fixed and moveable electrodes comprise one or more of a plurality of conductive layers, the plurality of conductive layers including at least three layers. The fixed electrode includes a stacked arrangement of two or more spaced apart conductive layers of the plurality of conductive layers.

Abstract: A multiple coil spring MEMS resonator includes a center anchor and a resonator body including two or more coil springs extending in a spiral pattern from the center anchor to an outer closed ring. Each pair of coil springs originates from opposing points on the center anchor and extends in the spiral pattern to opposing points on the outer ring. The number of coil springs, the length and the width of the coil springs and the weight of the outer ring are selected to realize a desired resonant frequency.

Abstract: A micromechanical device includes a substrate, a micromechanical structure supported by the substrate and configured for overtone resonant vibration relative to the substrate, and a plurality of electrodes supported by the substrate and spaced from the micromechanical structure by respective gaps. The plurality of electrodes include multiple drive electrodes configured relative to the micromechanical structure to excite the overtone resonant vibration with a differential excitation signal, or multiple sense electrodes configured relative to the micromechanical structure to generate a differential output from the overtone resonant vibration.

Abstract: A device includes a substrate, an electrode supported by the substrate, an anchor supported by the substrate, and a composite structure supported by the anchor, disposed adjacent the electrode, and configured for resonant vibration. The composite structure includes an external layer and an internal dielectric region covered by the external layer.

Abstract: A multiple coil spring MEMS resonator includes a center anchor and a resonator body including two or more coil springs extending in a spiral pattern from the center anchor to an outer closed ring. Each pair of coil springs originates from opposing points on the center anchor and extends in the spiral pattern to opposing points on the outer ring.

Abstract: A micromechanical device includes a substrate, a micromechanical structure supported by the substrate and configured for overtone resonant vibration relative to the substrate, and a plurality of electrodes supported by the substrate and spaced from the micromechanical structure by respective gaps. The plurality of electrodes include multiple drive electrodes configured relative to the micromechanical structure to excite the overtone resonant vibration with a differential excitation signal, or multiple sense electrodes configured relative to the micromechanical structure to generate a differential output from the overtone resonant vibration.

Abstract: A method of configuring a device comprising a MEMS resonator includes initiating operation of the device, estimating a first parameter of the MEMS resonator based on the initiated operation, the first parameter not varying with the bias voltage, monitoring the operation of the device at a plurality of levels of the bias voltage, calculating a second parameter of the MEMS resonator based on the monitored operation, the second parameter varying with the bias voltage, determining an operational level of the bias voltage based on the estimated first parameter and the calculated second parameter, and configuring the device in accordance with the determined operational level of the bias voltage.

Abstract: A device has a resonator coupled to input and output nodes, the resonator being characterized by a transducer to drive the output node, and further characterized by a feedthrough capacitance such that portions of the input signal bypass the transducer to allow a spurious signal to reach the output node. The device includes a compensation capacitor coupled to the output node to define a compensation capacitance in accordance with the feedthrough capacitance. A phase inversion circuit is coupled to the compensation capacitance to generate a compensation signal and coupled to the output node such that the spurious signal is offset by the compensation signal. In some cases, a differential amplifier of the phase inversion circuit has the compensation capacitance in a feedback path to offset the feedthrough capacitance. In these and other cases, the compensation capacitance and the feedthrough capacitance may be unmatched to avoid overcompensation.

Abstract: Disclosed herein are devices and methods for generating a modulated signal with a MEMS resonator, or microresonator. A bias, or polarization, voltage for activating the MEMS resonator is determined by a control signal, or input voltage, indicative of information to be carried by the modulated signal. In some cases, the MEMS resonator may be driven by an oscillator circuit to facilitate operation of the MEMS resonator. The control signal may include an amplitude modulated voltage or a digital data stream such that output signals of the MEMS resonator or oscillator circuit may carry information via frequency modulation, such as frequency shift keying modulation.

Abstract: A device has a resonator coupled to input and output nodes, the resonator being characterized by a transducer to drive the output node, and further characterized by a feedthrough capacitance such that portions of the input signal bypass the transducer to allow a spurious signal to reach the output node. The device includes a compensation capacitor coupled to the output node to define a compensation capacitance in accordance with the feedthrough capacitance. A phase inversion circuit is coupled to the compensation capacitance to generate a compensation signal and coupled to the output node such that the spurious signal is offset by the compensation signal. In some cases, a differential amplifier of the phase inversion circuit has the compensation capacitance in a feedback path to offset the feedthrough capacitance. In these and other cases, the compensation capacitance and the feedthrough capacitance may be unmatched to avoid overcompensation.

Abstract: Disclosed herein is a timing device that includes a resonator device to generate a resonator output signal at a frequency offset from a desired frequency, a counter configured to generate an extraction signal in accordance with the frequency offset, and a timing signal generator configured to track time with a count based on the resonator output signal and modified by the extraction signal downward to reach the desired frequency.

Abstract: A method for modifying the resonance frequency of a micro-mechanical resonator, and resonators on which the method is practiced. A packaged resonator is trimmed by directing electromagnetic energy to the resonator through a transparent portion of the package. The removal of mass (by the energy) affects the resonance frequency of the resonator in a predictable manner. In some embodiments, the energy is sourced from a femtosecond laser. In some variations of the illustrative embodiment, the amount of mass to be removed is determined as a function of its location on the resonator. A mass-trimming map is developed that identifies a plurality of potential mass-trimming sites on the resonator. A site can be classified as a fine-tuning site or a coarse-tuning site as a function of the degree to which mass removal at those sites affects the resonance frequency. The sites can also be characterized as a function of their position relative to features of the resonator (e.g., nodal lines, etc.).