Abstract: The present disclosure relates to a capacitance detection circuit using a sample and hold circuit to simplify the circuit configuration and improve temperature characteristics. The capacitance detection circuit includes a constant current part, a sawtooth waveform generator for generating a sawtooth waveform voltage, a sensing part, a peak value detector for detecting a peak value of a sawtooth waveform voltage in a non-signal period and a peak value of a sawtooth waveform voltage in a sensing period input from the sawtooth waveform generator, a constant current automatic control comparator for providing a negative feedback loop for generating a reference voltage when there is no signal to the constant current part, a sample and hold part, an alternative current (AC) amplifier, a zero volt clamp detector and a voltage comparator for outputting a detection signal.

Abstract: A high-sensitivity capacitive sensor circuit having improved sensitivity by implementing a plurality of detection units using charging and discharging, has: an oscillation unit for generating a control clock; a first charge/discharge unit connected to a sensing unit electrode, which generates a sensing signal while being charged/discharged according to the control clock; a second charge/discharge unit connected in parallel to the first charge/discharge unit, which generates a reference signal while being charged/discharged according to the control clock; and a detection unit for detecting a change in the capacitance on the side of the sensing unit electrode by comparing the sensing signal from the first charge/discharge unit with the reference signal from the second charge/discharge unit.

Abstract: A high-sensitivity capacitive sensor circuit having improved sensitivity by implementing a plurality of detection units using charging and discharging, has: an oscillation unit for generating a control clock; a first charge/discharge unit connected to a sensing it electrode, which generates a sensing signal while being charged/discharged according to the control clock; a second charge/discharge unit connected in parallel to the first charge/discharge unit, which generates a reference signal while being charged/discharged according to the control clock; and a detection unit for detecting a change in the capacitance on the side of the sensing unit electrode by comparing the sensing signal from the first charge/discharge unit with the reference signal from the second charge/discharge unit.

Abstract: A fabrication method of a silicon condenser microphone having an additional back chamber. The method includes applying an adhesive on a substrate and mounting a chamber container thereon by using a mounter; curing the adhesive holding the chamber container; applying an adhesive on the chamber container and mounting a micro electro mechanical system (MEMS) chip thereon by using a mounter; curing the adhesive holding the MEMS chip; and attaching the substrate on which devices are mounted to a case, wherein a back chamber formed by the chamber container is added to a back chamber of the MEMS chip. Therefore, a silicon condenser microphone fabricated by using the method may have improved sensitivity by increasing the small back chamber space of the a micro electro mechanical system (MEMS) chip itself and reduced noise including total harmonic distortion (THD).

Abstract: Provided is a MEMS microphone package having a sound hole in a PCB, which can ground-connect a metal case to a main board using an assembly process including bending and clamping an end of the case. The MEMS microphone package includes a tetragonal container-shaped metal case having an open-side to insert components into an inner space, and a chamfered end on the open-side to easily perform a curling operation, a printed circuit board (PCB) substrate to which a MEMS microphone chip and an application specific integrated circuit (ASIC) chip are mounted, the PCB substrate being inserted into the metal case and having a sound hole for introducing an external sound, and a support configured to support the PCB substrate in the curling operation and define a space between the metal case and the PCB substrate.

Abstract: Provided are a method of forming a sound hole in a condenser microphone case that prevents foreign substances from being thrown to improve reliability and the condenser microphone case. The method of forming the sound hole in the condenser microphone case includes cutting a portion of a bottom surface of a metal case in the cylindrical metal case having an opened side to mount components for a microphone, and simultaneously, pressing the cut portion to form a sound hole having a gap shape at the cut portion.

Abstract: Disclosed is a silicone based condenser microphone comprising: a metal case which includes a sound hole, a board which is mounted with a MEMS microphone chip and an ASIC chip having an electric voltage pump and a buffer IC and is formed with a connecting pattern for joining with the metal case. A fixing material for fixing the metal case to the board, and an adhesive for applying to the whole part where the metal case fixed to the board by the fixing material is joined with the board to bond the metal case to the board. Therefore, the metal case is tack-welded to the board by a laser to fix the case to the board and then the case is bonded to the board with the adhesive, thereby decreasing an inferiority ratio and strengthening a joining force and thus enhancing a mechanical firmness and highly resisting noise from the outside.

Abstract: A micro electro mechanical systems (MEMS) microphone, and a method of manufacturing the MEMS microphone having an interval between a membrane and a back plate, the interval being correctly adjusted by forming the membrane and the back plate after an air-gap forming portion on a silicon substrate. Since the membrane and/or the back plate are/is formed by electroless plating, a sacrificial layer is easily planarized, and a residual stress is easily removed or controlled. The MEMS microphone includes a silicon substrate in which a back chamber is formed and on which an air-gap forming portion is formed above the chamber by etching the silicon substrate to a predetermined depth above the chamber; a membrane formed on the air-gap forming portion of the silicon substrate or the silicon substrate; and a back plate that is formed on the air-gap forming portion or the silicon substrate so as to be spaced apart from the membrane, wherein an air gap is formed between the membrane and the back plate.

Abstract: A MEMS microphone package having improved acoustic properties, and to a packaging method, which involve adding a vent path in the packaging process to improve equilibrium between internal and external air pressure. The MEMS microphone package includes a MEMS microphone chip, in which a back plate and a diaphragm structure are formed in a body by using MEMS process techniques; a substrate for mounting the MEMS microphone chip thereon; a vent path which is formed between the MEMS microphone chip and the substrate by applying an adhesive only to a portion of the substrate and adhering the MEMS microphone chip to the substrate; and a case which is adhered to the substrate and forms a space for accommodating the MEMS microphone chip, wherein acoustic properties of the MEMS microphone package are improved as air pressure inside the MEMS microphone chip and air pressure outside the MEMS microphone chip form air equilibrium via the vent path.

Abstract: A fabrication method of a silicon condenser microphone having an additional back chamber. The method includes applying an adhesive on a substrate and mounting a chamber container thereon by using a mounter; curing the adhesive holding the chamber container; applying an adhesive on the chamber container and mounting a micro electro mechanical system (MEMS) chip thereon by using a mounter; curing the adhesive holding the MEMS chip; and attaching the substrate on which devices are mounted to a case, wherein a back chamber formed by the chamber container is added to a back chamber of the MEMS chip. Therefore, a silicon condenser microphone fabricated by using the method may have improved sensitivity by increasing the small back chamber space of the a micro electro mechanical system (MEMS) chip itself and reduced noise including total harmonic distortion (THD).

Abstract: A condenser microphone assembly without electrets formed on a rear pole plate, and having an electrically floating diaphragm and improved capacitance.

Abstract: A multifunctional micro speaker including a frame; a diaphragm having an outer circumferential portion fixed to the frame; a voice coil fixed to a lower surface of the diaphragm; a first member having one side fixed to the frame and having a predetermined elasticity; a yoke fixed to the first member and comprising a receiving groove; a first permanent magnet fixed to a bottom surface of the receiving groove; a plate fixed to an upper surface of the first permanent magnet; a second member having one side fixed to the frame, spaced apart from the first member in a downwards direction and having a predetermined elasticity; and a second magnet fixed to the second member and spaced apart from the first member and the yoke.

Abstract: A condenser microphone includes a conductive layer which is partially disposed on an insulation ring of a second base to reduce stray capacitance. The condenser microphone includes: a conductive case with an opened surface, wherein an end portion of the case is bent to attach to a printed circuit board (PCB); a diaphragm mounted inside the case a backplate facing the diaphragm with a predetermined distance set by a spacer; a first base made of an insulating ring to electrically insulate the backplate from the case; a second base electrically connected to the backplate by disposing a conductive layer on a portion of a ring formed of an insulating material. The PCB has a circuit component and a conductive pattern for connecting the second base, and on another surface has a conductive pattern for connecting the bent end portion of the case and a connection terminal to an external circuit.

Abstract: A directional silicon condenser microphone which has an additional back chamber includes a case having a front sound hole for passing through a front sound; an acoustic delay device for delaying a phase of a sound; a substrate including a chamber case, a MEMS chip having an additional back chamber formed by the chamber case, an ASIC chip for operating the MEMS chip, a conductive pattern for bonding the substrate to the case, and a rear sound hole for passing through a rear sound. The case is fixed to the substrate; and an adhesive for bonding the case and the substrate is applied to an entirety of a bonding surface of the case and the substrate.

Abstract: A silicon condenser microphone has an additional back chamber and a sound hole in a PCB. The microphone includes a case for blocking an external sound; a substrate including a chamber case, a MEMS chip having an additional back chamber formed by the chamber case, an ASIC chip for operating the MEMS chip, a conductive pattern for a bonding to the case, and a sound hole for passing the external sound. A fixing means fixes the case to the substrate and an adhesive is applied to an entirety of a bonding surface of the case and the substrate fixed by the fixing means. When the sound hole is formed through the PCB instead of the case, the mounting space for a microphone is reduced. The chamber case forms the additional back chamber under the MEMS chip and is employed to increase back chamber space to improve sensitivity and reduce noise.

Abstract: A directional silicon condenser microphone having an additional back chamber is disclosed. The directional silicon condenser microphone comprises a case having a front sound hole for passing through a front sound; a acoustic delay device for delaying a phase of a sound; a substrate including a chamber case, a MEMS chip having an additional back chamber formed by the chamber case, an ASIC chip for operating the MEMS chip, a conductive pattern for bonding the substrate to the case, and a rear sound hole for passing through a rear sound; a fixing means for fixing the case to the substrate; and an adhesive for bonding the case and the substrate, wherein the adhesive is applied to an entirety of a bonding surface of the case and the substrate fixed by the fixing means.

Abstract: Disclosed are a silicon based condenser microphone and a packaging method for the silicon based condenser microphone. The silicon based condenser microphone comprises a metal case, and a board which is mounted with a MEMS microphone chip and an ASIC chip having an electric voltage pump and a buffer IC and is formed with a connecting pattern for bonding with the metal case, wherein the connecting pattern is welded to the metal case. The method for packaging a silicon based condenser microphone includes the steps of inputting a board which is mounted with a MEMS chip and an ASIC chip and is formed with a connecting pattern; inputting a metal case, aligning the metal case on the connecting pattern of the board, and welding an opened end of the metal case to the connecting pattern of the board. Thus, the metal case is welded to the board by the laser.

Abstract: A condenser microphone employs a wide band stop filter, having improved resistance to electrostatic discharge. This includes providing a condenser microphone used for a multi-band by comprising a wide band stop filter capable of efficiently blocking a wide band signal including low frequency and radio frequency used in a mobile communication. A condenser microphone includes: an acoustic module for converting sound pressure into an electric signal; an FET for amplifying the electric signal; and a wide band stop filter for blocking a wide band signal including low frequency and radio frequency output from the FET. The filter is realized by resistors and/or capacitors which are connected selectively according to the radio frequency band between the drain and the source of the FET. The range capable of removing EM noise is widened, an excellent filtering effect of noise is obtained, and resistance of electrostatic discharge applied from outside is improved.

Abstract: Provided are a method of forming a sound hole in a condenser microphone case that prevents foreign substances from being thrown to improve reliability and the condenser microphone case. The method of forming the sound hole in the condenser microphone case includes cutting a portion of a bottom surface of a metal case in the cylindrical metal case having an opened side to mount components for a microphone, and simultaneously, pressing the cut portion to form a sound hole having a gap shape at the cut portion.

Abstract: A condenser microphone includes a conductive layer which is partially disposed on an insulation ring of a second base to reduce stray capacitance. The condenser microphone includes: a conductive case with an opened surface, wherein an end portion of the case is bent to attach to a printed circuit board (PCB); a diaphragm mounted inside the case a backplate facing the diaphragm with a predetermined distance set by a spacer; a first base made of an insulating ring to electrically insulate the backplate from the case; a second base electrically connected to the backplate by disposing a conductive layer on a portion of a ring formed of an insulating material. The PCB has a circuit component and a conductive pattern for connecting the second base, and on another surface has a conductive pattern for connecting the bent end portion of the case and a connection terminal to an external circuit.