Abstract: An integrated package of at least one environmental sensor and at least one MEMS acoustic sensor is disclosed. The package contains a shared port that exposes both sensors to the environment, wherein the environmental sensor measures characteristics of the environment and the acoustic sensor measures sound waves. The port exposes the environmental sensor to an air flow and the acoustic sensor to sound waves. An example of the acoustic sensor is a microphone and an example of the environmental sensor is a humidity sensor.

Abstract: A method and circuit for testing an acoustic sensor are disclosed. In a first aspect, the method comprises using electro-mechanical features of the acoustic sensor to measure characteristic of the acoustic sensor. In a second aspect, the method comprises utilizing an actuation signal to evaluate mechanical characteristics of the acoustic sensor. In a third aspect, the method comprises using a feedthrough cancellation system to measure a capacitance of the acoustic sensor. In the fourth aspect, the circuit comprises a mechanism for driving an electrical signal into a signal path of the acoustic sensor to cancel an electrical feedthrough signal provided to the signal path, wherein any of the electrical signal and the electrical feedthrough signal are within or above an audio range.

Abstract: An acoustic sensor system has an acoustic sensor with a cavity, a cavity leakage, and a cavity pressure. The acoustic sensor system further has a test controller coupled to the acoustic sensor that causes a change in the cavity pressure. A response of the acoustic sensor to the change in the cavity pressure is used to measure the cavity leakage.

Abstract: An integrated package of at least one environmental sensor and at least one MEMS acoustic sensor is disclosed. The package contains a shared port that exposes both sensors to the environment, wherein the environmental sensor measures characteristics of the environment and the acoustic sensor measures sound waves. The port exposes the environmental sensor to an air flow and the acoustic sensor to sound waves. An example of the acoustic sensor is a microphone and an example of the environmental sensor is a humidity sensor.

Abstract: The present invention relates to low power, low cost, and compact gas sensors and methods for making the same. In one embodiment, the gas sensor includes a heating element embedded in a suspended structure overlying a substrate. The heating element is configured to generate an amount of heat to bring the chemical sensing element to an operating temperature. The chemical sensing element is thermally coupled to the heating element. The chemical sensing element is also exposed to an environment that contains the gas to be measured. In one embodiment, the chemical sensing element comprises a metal oxide compound having an electrical resistance based on the concentration of a gas in the environment and the operating temperature of the chemical sensing element. In this embodiment, the operating temperature of the chemical sensing element is greater than room temperature and determined by the amount of heat generated by the heating element.

Abstract: Acoustic ambient temperature and humidity sensing based on determination of sound velocity is described, in addition to sensors, algorithms, devices, systems, and methods therefor. An exemplary embodiment employs sound velocity in the determination of ambient temperature and humidity. Provided implementations include determinations of sound velocity based on time of flight of a coded acoustic signal and/or based on resonance frequency of a Helmholtz resonator.

Abstract: Systems and techniques for processing a signal associated with a microphone are presented. The system includes a microphone component and a preamplifier. The microphone component is contained in a housing. The preamplifier includes an input buffer that receives a signal generated by the microphone component. The input buffer also generates an output signal that comprises a direct current (DC) voltage offset in comparison to the signal, where the preamplifier controls a degree of the DC voltage offset based on a control signal.

Abstract: A micro electro-mechanical system (MEMS) acoustic sensor is disclosed. The acoustic sensor comprises a backplate and a diaphragm. The acoustic sensor further comprises a flexible member and optional spacer member disposed between the backplate and the diaphragm resulting in a gap between the backplate and the diaphragm. The gap can vary in response to impinging pressure on the diaphragm based on the design of the flexible member and resulting in a variable capacitance between the backplate and the diaphragm. The change in the gap can result in a change in an electrical characteristic associated with the variable capacitance and can be converted to an electrical output signal corresponding to the impinging pressure on the diaphragm. The flexible member can be part of the backplate or diaphragm.

Abstract: A MEMS acoustic sensor includes a transducer with a frequency response with a gain peak, and a peak reduction circuit with a frequency response and coupled to the transducer. The frequency response of the peak reduction circuit causes attenuation of the gain peak.

Abstract: A time-division-multiplexing (TDM) based noise cancelation headphone is presented herein. A headphone can include an earbud including a speaker, and a TDM based bus that electrically couples the earbud to a portable electronic device. Further, the headphone can include a first micro-electro-mechanical system (MEMS) microphone that is configured to receive a first set of acoustic waves outside of an ear canal, generate first microphone information based on the first set of acoustic waves, and send, utilizing the TDM based bus, the first microphone information directed to the portable electronic device. The speaker is configured to receive, utilizing the TDM based bus, feedforward noise cancelation information associated with the first microphone information from the portable electronic device, and generate, based on the feedforward noise cancelation information, sound within a portion of the ear canal.

Abstract: A method and system for image stabilization is disclosed. The image stabilization system includes a first pair of light sensors placed along an axis relative to a first axis, each light sensor is configured to provide a signal indicative of intensity of light received by the light sensor. The image stabilization system further includes a first directional light filter configured to selectively permit passage of incident light to the first pair of light sensors based on an angle of the incident light with reference to the first axis. An image stabilization circuit is configured to receive a pair of signals from the first pair of light sensors and generates a first signal indicative of a change in the angle of incidence of the incident light with reference to the first axis.

Abstract: A MEMS capacitive sensing interface includes a sense capacitor having a first terminal and a second terminal, and having associated therewith a first electrostatic force. Further included in the MEMS capacitive sensing interface is a feedback capacitor having a third terminal and a fourth terminal, the feedback capacitor having associated therewith a second electrostatic force. The second and the fourth terminals are coupled to a common mass, and a net electrostatic force includes the first and second electrostatic forces acting on the common mass. Further, a capacitance measurement circuit measures the sense capacitance and couples the first terminal and the third terminal. The capacitance measurement circuit, the sense capacitor, and the feedback capacitor define a feedback loop that substantially eliminates dependence of the net electrostatic force on a position of the common mass.

Abstract: Various embodiments provide for an integrated temperature sensor and microphone package where the temperature sensor is located in, over, or near an acoustic port associated with the microphone. This placement of the temperature sensor near the acoustic port enables the temperature sensor to more accurately determine the ambient air temperature and reduces heat island interference cause by heat associated with the integrated circuit. In an embodiment, the temperature sensor can be a thermocouple formed over a substrate, with the temperature sensing portion of the thermocouple formed over the acoustic port. In another embodiment, the temperature sensor can be formed on an application specific integrated circuit that extends into or over the acoustic port. In another embodiment, a thermally conductive channel in a substrate can be placed near the acoustic port to enable the temperature sensor to determine the ambient temperature via the channel.

Abstract: Systems and techniques for processing a signal associated with a microphone are presented. The system includes a microphone component and a preamplifier. The microphone component is contained in a housing. The preamplifier includes an input buffer that receives a signal generated by the microphone component. The input buffer also generates an output signal that comprises a direct current (DC) voltage offset in comparison to the signal, where the preamplifier controls a degree of the DC voltage offset based on a control signal.

Abstract: Systems and techniques for detecting blockage associated with a microelectromechanical systems (MEMS) microphone of a device are presented. The device includes a MEMS acoustic sensor and a processor. The MEMS acoustic sensor is contained in a cavity within the device. The processor is configured to detect a blockage condition associated with an opening of the cavity that contains the MEMS acoustic sensor.

Abstract: Signal processing for an acoustic sensor bi-directional communication channel is presented herein. The acoustic sensor can comprise a micro-electro-mechanical system (MEMS) transducer configured to generate, based on an acoustic pressure, an audio output; and a bi-directional communication component configured to send and/or receive data that has been superimposed on the audio output using common mode signaling, time division multiplexing, or frequency separation. In an example, a signal processing component is configured to send the audio output directed to an external device utilizing differential mode signaling between respective pins of the acoustic sensor; and send the data utilizing the common mode signaling comprising a sum of voltages of the respective pins. In other examples, the signal processing component is configured to send and/or receive the data, and send the audio output, during different time periods; or send the data based on a frequency range outside an audio band.

Abstract: A MEMS capacitive sensing interface includes a sense capacitor having a first terminal and a second terminal, and having associated therewith a first electrostatic force. Further included in the MEMS capacitive sensing interface is a feedback capacitor having a third terminal and a fourth terminal, the feedback capacitor having associated therewith a second electrostatic force. The second and the fourth terminals are coupled to a common mass, and a net electrostatic force includes the first and second electrostatic forces acting on the common mass. Further, a capacitance measurement circuit measures the sense capacitance and couples the first terminal and the third terminal. The capacitance measurement circuit, the sense capacitor, and the feedback capacitor define a feedback loop that substantially eliminates dependence of the net electrostatic force on a position of the common mass.

Abstract: Microelectromechanical systems (MEMS) pressure sensors having a leakage path are described. Provided implementations can comprise a MEMS pressure sensor system associated with a back cavity and a membrane that separates the back cavity and an ambient atmosphere. A pressure of the ambient atmosphere is determined based on a parameter associated with movement of the membrane.

Abstract: A method and system for measuring displacement of a structure is disclosed. The method and system comprise providing a first capacitance and providing a second capacitance. The first and second capacitances share a common terminal. The method and system further include determining a difference of the inverses of the value of the first and second capacitances when the structure is displaced. The first capacitance varies in inverse relation to the displacement of the structure.

Abstract: An integrated package of at least one environmental sensor and at least one MEMS acoustic sensor is disclosed. The package contains a shared port that exposes both sensors to the environment, wherein the environmental sensor measures characteristics of the environment and the acoustic sensor measures sound waves. The port exposes the environmental sensor to an air flow and the acoustic sensor to sound waves. An example of the acoustic sensor is a microphone and an example of the environmental sensor is a humidity sensor.