Abstract: A condenser microphone mountable on a main PCB includes a cylinder-shaped case having opened and closed sides; a first metal ring inserted into the case; a disk-shaped back plate having a sound hole to be connected electrically to the case through the first metal ring; a spacer; an insulating ring to provide electrical insulation and mechanical support. A diaphragm is inserted into the insulating ring and faces the back plate while interposing the spacer between the diaphragm and the back plate. A second metal ring is connected electrically to the diaphragm and mechanically supports the diaphragm, and a PCB is mounted and forms with a sound hole. The PCB is connected to the back plate through the second metal ring and the case, and the PCB includes connection terminals.

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: A condenser microphone mountable on a main PCB includes a cylinder-shaped case having opened and closed sides; a first metal ring inserted into the case; a disk-shaped back plate having a sound hole to be connected electrically to the case through the first metal ring; a spacer; an insulating ring to provide electrical insulation and mechanical support. A diaphragm is inserted into the insulating ring and faces the back plate while interposing the spacer between the diaphragm and the back plate. A second metal ring is connected electrically to the diaphragm and mechanically supports the diaphragm, and a PCB is mounted and forms with a sound hole. The PCB is connected to the back plate through the second metal ring and the case, and the PCB includes connection terminals.

Abstract: A surface mounted device (SMD) type biased condenser microphone includes two terminals for a surface mounting process. The SMD type biased condenser microphone includes a grounding terminal for connecting with an external circuit, a diaphragm/backplate set, one end of which is connected to the grounding terminal, for varying a capacity according to an intensity of sound pressure and converting sound into an electric signal, a DC-DC converter for providing a bias voltage so as to form an electrostatic field at one side of the diaphragm/backplate set, a buffer IC for amplifying the electric signal from the diaphragm/backplate set, and a decoupling capacitor for preventing the bias voltage output from the DC-DC converter from being directly applied to the buffer IC and transferring the electric signal from the diaphragm/backplate set to the buffer IC.

Abstract: 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.

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.