476 results about "Capacitive microphone" patented technology

A condenser microphone includes a support, a plate having a fixed electrode bridged across the supports, a diaphragm, which has a moving electrode at a center portion thereof and which vibrates due to sound waves applied thereto, and a spacer, in which a first end is fixed to the plate, and a second end is fixed to the near-end portion of the diaphragm so as to surround the center portion of the diaphragm, wherein an air gap is formed between the plate and the diaphragm. This reduces the tensile stress of the diaphragm so as to increase the amplitude of vibration of the diaphragm. Hence, it is possible to increase the sensitivity of the condenser microphone. A structure constituted of the plate, the diaphragm, and the spacer is bridged across the support by means of the bridges, which absorb the residual stress of the diaphragm due to the deformation thereof.

This invention relates to a micromachined capacitive microphone having a shallowly corrugated diaphragm that is anchored at one or more locations on the support has a plurality of dimples to support itself and rest freely on the perforated backplate. The diaphragm whose ends are not anchored is bounded by the taps of edge rail. Also disclosed includes: a fixed perforated backplate having one or more regions; an adjustable cantilever formed by the diaphragm, the support and the backplate; a plurality of dimples maintaining vertical separation between diaphragm and backplate; and the patterning of conductor electrodes carried by diaphragm and backplate.

A condenser microphone is provided having a transducer element. A diaphragm has an electrically conductive portion. A back-plate has an electrically conductive portion. A DC bias voltage element is operatively coupled to the diaphragm and the back-plate. A collapse detection element is adapted to determine a physical parameter value related to a separation between the diaphragm and the back-plate. A collapse control element is adapted to control the DC bias voltage element based on the determined physical parameter value.

Methods and apparatus automatically cancel or attenuate an unwanted signal (such as low frequencies from wind buffets) from, and/or control frequency response of, a condenser microphone, or control the effective condenser microphone sensitivity before the signal reaches an ASIC or other processing circuit. As a result, the maximum amplitude signal seen by the processing circuit is limited, thereby preventing overloading the input of the processing circuit. Remaining (wanted) frequencies can be appropriately amplified to reduce the noise burden on further processing circuits. A corrective signal is applied to a bias terminal of the condenser microphone to cancel the unwanted signal. Optionally or alternatively, a controllable impedance is connected to a line that carries the signal generated by the MEMS microphone, so as to attenuate unwanted portions of the signal.

A capacitor microphone is constituted by a plate having a fixed electrode, a diaphragm including a center portion and at least one near-end portion that is fixed to the outer periphery, in which the center portion having a vibrating electrode, which is positioned relative to the fixed electrode and which vibrates in response to sound waves, is increased in rigidity in comparison with the near-end portion; and a spacer that is fixed to the plate and the near-end portion of the diaphragm and that has an air gap formed between the plate and the diaphragm. Alternatively, a diaphragm electrode is horizontally supported by extension arms extended from a circular plate thereof and is vertically held in a hanging state being apart from a fixed electrode with a controlled distance therebetween.

An electroacoustic transducer includes a condenser microphone, which includes a package having a cavity and a through-hole, a plate whose thickness is thinner than the length of the through-hole and which has a sound hole overlapping with the through-hole in plan view, and an electroacoustic transducer die, which is stored in the cavity of the package. The electroacoustic transducer die includes a fixed electrode and a diaphragm electrode, which are positioned opposite to each other and which are supported by and enclosed inside of a support. The sound hole of the plate is reduced in dimensions realizing a small sectional area and a small depth, thus realizing a high resonance frequency higher than the audio frequency range.

This invention mainly provides a SMT-type structure of the minimized and low-power silicon-based electret condenser microphone. Primarily integrates with the electret, silicon-based, MEMS and microphone techniques to implement the minimized and low-power silicon-based electret condenser microphone. The Silicon-based bi-diaphragm of the composite diaphragm-chip was coated with the low-dielectric macromolecule material to allow the microphone acquires the sufficient electrical charges. Moreover, the impedance matching element of the microphone that MOSFET was implemented by the MEMS technology. Conclusively, this silicon-based electret condenser microphone gains several achievements as the smallest volume, a lower bias voltage, a SMT-type structure, a lower residue stress and a lower assembly cost.

A capacitive microphone and method for making the same are provided. A backplate with a plurality of holes is formed on a substrate with at least one cavity, and a diaphragm is formed above the backplate. There is an air gap between the backplate and the diaphragm. The air gap and the cavity communicate with each other by each hole. The diaphragm and the backplate are separated by a first distance and a second distance which is smaller than the first distance, such that the difference is formed on the diaphragm. The second distance area is fastened through surface stiction produced by mist or other fluids.

A single crystal silicon micromachined capacitive microphone is disclosed. The microphone comprises a flexible plate made from a bottom layer of a first epitaxial single crystal silicon layer, a stiff and perforated plate made from a portion of a second epitaxial single crystal silicon layer, a supporting frame is made from a combination of lateral overgrowth of the first epitaxial single crystal silicon layer and a polysilicon layer grown or deposited on the surface of an insulating layer, and an air gap is formed by etching a portion of the first epitaxial single crystal silicon layer. Both the first epitaxial single crystal silicon layer and the second epitaxial single crystal silicon layer are developed from a single crystal silicon substrate. A micromaching technology based on selective formation and etching of porous single crystal silicon layers is used to make the microphone structure.

An air gap is formed between a first film having a first electrode film and a second film having a second electrode film. The first film has a stopper protruding toward the second film, and a recess communicating with the air gap is provided in the center of the stopper.

In a capacitor microphone, a diaphragm is positioned opposite to a fixed electrode for covering inner holes of a ring-shaped support, wherein when the diaphragm is deflected to approach the fixed electrode due to electrostatic attraction upon application of a bias voltage, internal stress that occurs on the diaphragm is canceled by compressive stress that is applied to the diaphragm in advance. The diaphragm is formed using a multilayered structure including a first thin film and a second thin film whose internal stress differs from the internal stress of the first thin film, thus adjusting the total internal stress thereof. The diaphragm can be formed in such a way that a center layer having a single-layered structure is sandwiched between first and second coating layers having controlled residual tensions and resistance against hydrofluoric acid.

The present invention relates to a condenser microphone assembly comprising an electro-acoustic transducer element comprising a diaphragm and a back plate, signal processing circuitry operatively connected to the transducer element so as to process signals generated by the transducer element, and a mode-setting circuitry for selectively setting the condenser microphone assembly in a test mode or an operational mode. The electro-acoustic sensitivity of the condenser microphone assembly, when operated in the test mode, is at least 40 dB lower than the corresponding electro-acoustic sensitivity of the assembly when operated in the operational mode. The present invention further relates to a method for determining a performance parameter of a signal processing circuitry mounted inside a housing of an assembled condenser microphone assembly.

A capacitance type microphone with a stress release membrane prepared at a low temperature and a preparation method thereof. The capacitance type microphone includes a substrate having at least a resonant cavity; a septum, arranged on the top of the resonant cavity and connected with the substrate for implementing a mechanical vibration when being excitated by an acoustic pressure wave; a back board, arranged on the top of the septum and having a plurality of perforations; an air gap is provided the back board and the septum; a capacitor is composed of the septum, the air gap and the back board. The method includes steps: forming the resonant cavity on the substrate; forming the septum on the top of the resonant cavity, wherein the septum is connected with the substrate; setting the back board on the top of the septum, wherein the back board has a plurality of perforations; forming the air gap between the back board and the septum. The invention is a MEMS capacitance type microphone processed by a completely low-temperature technique. It is capable of being used as a post IC circuit processing technique being compatible thereof. The structure of the vibration diaphragm of the capacitance type microphone is a stress-releasing structure, and is capable of reducing a parasitic capacitance. Comparing with the traditional initial stress release membrane, the invention improves the sensitivity of the microphone more effectively.

The invention relates to an electronic cigarette chip which is used for controlling the switching on and off of an electronic cigarette adopting a capacitive microphone according to capacitance change of the capacitive microphone. The electronic cigarette chip comprises a microphone capacitance detecting module and a heating wire driving circuit which are connected with each other, wherein the microphone capacitance detecting module is used for detecting the capacitance of the capacitive microphone, converting the capacitance of the capacitive microphone into a comparison signal, comparing the comparison signal with a smoking threshold value, and controlling the open and close of the heating wire driving circuit according to the comparing result. As the sensibility and reliability of the electronic cigarette chip are effectively improved, the electronic cigarette can generate smoke even under little sucking force, the phenomenon of smoking by false triggering is avoided, and the electronic cigarette chip solves a series of problems that the electronic cigarette is heated excessively, a plastic shell of the electronic cigarette is burnt, the service life of the electronic cigarette is shortened, the yield is low and the like caused by the long-time continuous false triggering smoking action of the conventional electronic cigarette chip.

A condenser microphone and a method of mounting a condenser microphone on a main PCB are provided. The method includes assembling the condenser microphone by assembling elements of the condenser microphone such that a vibration plate including a diaphragm and a backplate is directed toward an opened surface of a casing of the condenser microphone. The casing has a closed bottom surface and an opened surface opposite to the closed bottom surface. A PCB includes a sound hole. The assembled condenser microphone is positioned on a main PCB such that the sound hole of the PCB is aligned in accordance with a through hole formed in the main PCB. According to the present invention, if necessary, the main PCB can be mounted such that its elements surface is directed toward an inside of an electronic product, thereby maintaining good sound quality due to a short delivery path of sound waves.

The present invention provides a condenser microphone having a proximity sensor consisting of an infrared light emitting diode and an infrared photodetector, the condenser microphone preventing the occurrence of noise and the malfunctioning of the infrared photodetector when the infrared light emitting diode is lighted using an AC component. Specifically, the present invention provides a condenser microphone operated using a predetermined DC power source; an infrared light emitting diode 20 is lighted at a predetermined frequency by an oscillation circuit 22 using an AC component, and a microphone output is turned on and off by an output signal from the infrared photodetector 21 which is tuned to the predetermined frequency. The condenser microphone further includes two DC-DC converters 23 and 24 connected in parallel with the DC power source. One 23 of the DC-DC converters 23 supplies power to the infrared light emitting diode 20 and the oscillation circuit 22. The other DC-DC converter 24 supplies power to the infrared photodetector 21.