Abstract: A top port microelectromechanical systems (MEMS) microphone is presented herein. A device can include a substrate and a MEMS acoustic sensor mechanically attached to the substrate utilizing anchors. Spaces between the anchors can connect a first back volume corresponding to a bottom portion of the MEMS acoustic sensor with a second back volume to form a combined back volume. An acoustic seal can be placed on the MEMS acoustic sensor, and an enclosure placed on the acoustic seal and secured to the substrate. The acoustic seal can isolate a first portion of the enclosure corresponding to a front volume from a second portion of the enclosure corresponding to the combined back volume. The first portion of the enclosure can include an opening adapted to receive acoustic waves into the front volume, and the front volume can be acoustically coupled to a top portion of the MEMS acoustic sensor.

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: Microelectromechanical systems (MEMS) microphones associated with a tunable back cavity are described. Provided implementations can comprise a MEMS acoustic sensor element associated with a first back cavity, which first back cavity can be separated and/or acoustically coupled by a tuning port to a second back cavity. In addition, various physical and acoustic filtering configurations of MEMS microphones and tunable back cavities are described.

Abstract: A MEMS microphone has a stationary portion with a backplate having a plurality of apertures, and a diaphragm spaced from the backplate and having an outer periphery. As a condenser microphone, the diaphragm and backplate form a variable capacitor. The microphone also has a post extending between, and substantially permanently connected with, both the backplate and the diaphragm, and a set of springs securing the diaphragm to at least one of the post and the stationary portion. The post is positioned to be radially inward of the outer periphery of the diaphragm.

Abstract: A device and a microphone are disclosed. The device comprises a circuit board and a plurality of pads on the circuit board, wherein at least one of the plurality of pads is split into at least two portions that are electrically isolated from each other. The microphone comprises a circuit board, a seal structure on the circuit board, and a plurality of pads on the circuit board, wherein at least one of the plurality of pads is split into at least two portions that are electrically isolated from each other.

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: 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: A MEMS microphone has a stationary portion with a backplate having a plurality of apertures, and a diaphragm spaced from the backplate and having an outer periphery. As a condenser microphone, the diaphragm and backplate form a variable capacitor. The microphone also has a post extending between, and substantially permanently connected with, both the backplate and the diaphragm, and a set of springs securing the diaphragm to at least one of the post and the stationary portion. The post is positioned to be radially inward of the outer periphery of the diaphragm.

Abstract: A MEMS device includes a MEM-CMOS module having a CMOS chip and a MEMS chip. The MEMS chip includes a port exposed to the environment. The MEMS device further includes a printed circuit board (PCB) with an aperture, wherein the MEMS-CMOS module is directly mounted on the PCB.

Abstract: A MEMS microphone system suited for harsh environments. The system uses an integrated circuit package. A first, solid metal lid covers one face of a ceramic package base that includes a cavity, forming an acoustic chamber. The base includes an aperture through the opposing face of the base for receiving audio signals into the chamber. A MEMS microphone is attached within the chamber about the aperture. A filter covers the aperture opening in the opposing face of the base to prevent contaminants from entering the acoustic chamber. A second metal lid encloses the opposing face of the base and may attach the filter to this face of the base. The lids are electrically connected with vias forming a radio frequency interference shield. The ceramic base material is thermally matched to the silicon microphone material to allow operation over an extended temperature range.

Abstract: A microphone system has a lid coupled with a base to form a package with an interior chamber. The package has a top, a bottom, and a plurality of sides, and at least one of those sides has a portion with a substantially planar surface forming an opening for receiving an acoustic signal. The microphone system also has a microphone die positioned within the interior chamber. The microphone is positioned at a non-orthogonal, non-zero angle with regard to the opening in the at least one side.

Abstract: A MEMS microphone is capable of operating with less-than-one-volt bias voltage. An exemplary MEMS microphone can operate directly from a power rail (i.e., directly from VDD), i.e., without a DC-to-DC step-up voltage converter or other high bias voltage generator. The MEMS microphone has high mechanical and electrical sensitivity due, at least in part, to having high-compliance, i.e. low stiffness, springs and a relatively small gap between its diaphragm and its parallel conductive plate. In some embodiments, a diode-based voltage reference or a bandgap voltage reference supplies the bias voltage.

Abstract: A MEMS microphone system suited for harsh environments. The system uses an integrated circuit package. A first, solid metal lid covers one face of a ceramic package base that includes a cavity, forming an acoustic chamber. The base includes an aperture through the opposing face of the base for receiving audio signals into the chamber. A MEMS microphone is attached within the chamber about the aperture. A filter covers the aperture opening in the opposing face of the base to prevent contaminants from entering the acoustic chamber. A second metal lid encloses the opposing face of the base and may attach the filter to this face of the base. The lids are electrically connected with vias forming a radio frequency interference shield. The ceramic base material is thermally matched to the silicon microphone material to allow operation over an extended temperature range.

Abstract: A MEMS microphone has a stationary portion with a backplate having a plurality of apertures, and a diaphragm spaced from the backplate and having an outer periphery. As a condenser microphone, the diaphragm and backplate form a variable capacitor. The microphone also has a post extending between, and substantially permanently connected with, both the backplate and the diaphragm, and a set of springs securing the diaphragm to at least one of the post and the stationary portion. The post is positioned to be radially inward of the outer periphery of the diaphragm.

Abstract: A circuit electrically connects a MEMS microphone with a single line transmitting both a DC power signal and an AC information signal. The MEMS microphone has a power interface for receiving the power signal, and an information interface for delivering the information signal. In such embodiments, the circuit includes a pair of lines that separate the power and information signals. To that end, the circuit has an information line configured to connect with the information interface of the MEMS microphone, and a power line configured to connect with the power interface of the MEMS microphone.

Abstract: A side-ported MEMS microphone package defines an acoustic path from a side of the package substrate to a microphone die disposed within a chamber defined by the substrate and a lid attached to the substrate. Optionally or alternatively, a circuit board, to which the microphone package is mounted, may define an acoustic path from an edge of the circuit board to a location under the microphone package, adjacent a bottom port on the microphone package. In either case, the acoustic path may be a hollow passage through at least a portion of the substrate or the circuit board. The passage may be defined by holes, channels, notches, etc. defined in each of several layers of a laminated substrate or circuit board, or the passage may be defined by holes drilled, molded or otherwise formed in a solid or laminated substrate or circuit board.

Abstract: A MEMS microphone has an SOI wafer, a backplate formed in a portion of the SOI wafer, and a diaphragm adjacent to and movable relative to the backplate. The backplate has at least one trench that substantially circumscribes a central portion of the backplate.

Abstract: A MEMS microphone is capable of operating with less-than-one-volt bias voltage. An exemplary MEMS microphone can operate directly from a power rail (i.e., directly from VDD), i.e., without a DC-to-DC step-up voltage converter or other high bias voltage generator. The MEMS microphone has high mechanical and electrical sensitivity due, at least in part, to having high-compliance, i.e. low stiffness, springs and a relatively small gap between its diaphragm and its parallel conductive plate. In some embodiments, a diode-based voltage reference or a bandgap voltage reference supplies the bias voltage.

Abstract: A side-ported MEMS microphone package defines an acoustic path from a side of the package substrate to a microphone die disposed within a chamber defined by the substrate and a lid attached to the substrate. Optionally or alternatively, a circuit board, to which the microphone package is mounted, may define an acoustic path from an edge of the circuit board to a location under the microphone package, adjacent a bottom port on the microphone package. In either case, the acoustic path may be a hollow passage through at least a portion of the substrate or the circuit board. The passage may be defined by holes, channels, notches, etc. defined in each of several layers of a laminated substrate or circuit board, or the passage may be defined by holes drilled, molded or otherwise formed in a solid or laminated substrate or circuit board.