JP2009077053A - Capacitor microphone - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problem wherein the volume of a rear air space becomes small and hence satisfactory acoustic characteristics cannot be obtained in a conventional capacitor microphone having an acoustic hole at a circuit board side. <P>SOLUTION: In a capacitor microphone, a circuit board, a back electrode board, and a vibrating membrane unit are laminated. The circuit board packages electronic components. The back electrode board forms an electret layer on a back electrode. A connection board, which has an output electrode for electrically connecting the acoustic hole to the outside, is provided at an upper portion of the vibrating membrane unit, thus connecting the capacitor microphone to a main substrate by the connection substrate. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a condenser microphone formed by laminating a circuit board on which electronic components are mounted, a back electrode board in which an electret layer is formed on the back electrode, and a diaphragm unit to which a diaphragm is fixed, and particularly to a main circuit board. The present invention relates to a condenser microphone that can reduce the mounting height of the.

  In recent years, electret condenser microphones (hereinafter abbreviated as ECM) have been widely used as small and high-performance mycophones widely used in mobile phones, video cameras, digital cameras, and the like.

  The configuration of the conventional ECM disclosed in Patent Document 1 will be described below with reference to FIG. FIG. 11 is a sectional view of a conventional completed ECM. In FIG. 11, reference numeral 80 denotes an ECM. Reference numeral 2 denotes a circuit board. The circuit board 2 is formed of an insulating substrate, and the connection wiring 2a is formed on the upper surface side, the output electrode 2b is formed on the lower surface side, and the integrated circuit 11 and the electronic element 12 which are electronic components are mounted. Has been. 3 is a back electrode substrate, and the back electrode substrate 3 has a back electrode 4 formed of an electrode film on the top surface side of an insulating substrate 3a, and an electret layer 5 is formed on the top surface of the back electrode 4, A through hole 3 b that penetrates the insulating substrate 3 a is formed outside the back electrode 4 and the electret 5.

  Reference numeral 6 denotes a diaphragm unit, and the diaphragm unit 6 is integrated by attaching a conductive diaphragm 7 to the lower surface side of a diaphragm support frame 6a in which a metal film is formed on the surface of a metal material or an insulating member. Has been. Reference numeral 85 denotes a metal shield case having an acoustic hole 85a on the upper surface side. Further, 8 is a first spacer, and 9 is a second spacer.

  The ECM 80 has a structure in which the first spacer 8 is sandwiched between the circuit board 2 and the back electrode substrate 3 and the second spacer 9 is sandwiched between the back electrode substrate 3 and the vibrating membrane unit 6 and then bonded. An ECM capsule is formed by fixing and integrating with a material or the like, and the ECM 80 is completed by covering the ECM capsule with the shield case 85. The through-hole 3b is formed outside the back electrode 4 in the back electrode substrate 3, thereby ensuring ventilation of the upper and lower surfaces of the back electrode substrate 3 without reducing the area of the back electrode 4. It comes to get an effect.

Next, the operation of the ECM 80 will be described.
In the operation of the ECM 80 having the above configuration, the vibration film 7 having the conductive film on the surface and the back electrode 4 having the electret layer 5 formed on the surface form a capacitor with the second spacer 9 interposed therebetween. When the vibration film 7 is displaced by the air vibration of the acoustic input signal Ps input from the acoustic hole 85a, the capacitor converts the displacement into an electric signal, and the electric signal is transmitted from the conductive vibration film support frame 6a to the electric signal. The light is guided to the circuit board 2 through connection electrodes (not shown), processed by the integrated circuit 11, and then output from the output electrode 2b provided on the lower surface of the circuit board 2. Then, the vibration operation of the vibration film 7 is smoothed by the presence of the through hole 3b, and the acoustic characteristics are ensured.

  In order to improve acoustic characteristics in the ECM 80, the following conditions are necessary. That is, the front air chamber S1 is formed on the input side of the acoustic input signal Ps with the vibration film 7 interposed therebetween, and the rear air chamber S2 is formed on the opposite side of the vibration film 7. The rear air chamber S2 includes a space between the vibrating membrane 7 and the back electrode substrate 3, and a space between the back electrode substrate 3 and the circuit board 2 connected by a through hole 3b provided in the back electrode substrate 3. It is the total space.

  As for the relationship between the front air chamber S1 and the rear air chamber S2, the volume of the front air chamber S1 may be small as long as the sound pressure of the acoustic input signal Ps input from the acoustic hole 85a is transmitted to the vibrating membrane 7. In addition, the volume of the rear air chamber S2 needs to be increased so as not to hinder the vibration operation of the vibration film 7. In this respect, since the ECM 80 can use the space having a large volume between the back electrode substrate 3 and the circuit board 2 as the rear air chamber S2, it can be said that the ECM 80 has good acoustic characteristics.

  However, although the ECM 80 is a microphone excellent in acoustic characteristics, it has the following problems. That is, since the acoustic hole 85a of the ECM 80 is provided on the upper surface side of the shield case 85, when the ECM 80 is mounted on the main circuit board 100 such as a mobile phone, the upper surface side of the main circuit board 100 as shown in FIG. The output electrode 2b is attached by soldering. However, in this configuration, the distance between the case of the mobile phone or the like and the main circuit board 100 needs to be wider than the height of the ECM 80, which hinders the downsizing and thinning of the mobile phone or the like.

  As a proposal for solving this problem, there is an ECM described in Patent Document 2. The configuration of the ECM as the second conventional example disclosed in Patent Document 2 will be described below with reference to FIG. The basic configuration of the ECM shown in FIG. 12 is substantially the same as that of the ECM 80 shown in FIG. 11, and the same elements are denoted by the same reference numerals and redundant description is omitted.

  FIG. 12 is a cross-sectional view of an ECM 90 which is a second conventional example. The difference from the ECM 80 shown in FIG. 11 is that the shield case 95 is not provided with an acoustic hole, and secondly, the circuit board 2 is not provided. The acoustic hole 2c is formed at the center, and thirdly, the order of the members laminated inside the shield case 95 is the circuit board 2, the first spacer 8, the vibrating membrane unit 6, the second spacer 9, and the back electrode. That is, the substrate 3 and the third spacer 13 are laminated in this order.

  That is, the most different point of the ECM 90 with respect to the ECM 80 is that the acoustic hole 2 c is provided in the lower circuit board 2 without being provided in the upper shield case 95. As a result, in accordance with the input of the acoustic input signal Ps from the direction of the circuit board 2, the positional relationship between the back electrode substrate 3 and the diaphragm unit 6 is switched, and the diaphragm unit 6 is moved closer to the acoustic hole 2 c. It is arranged. Furthermore, a third spacer 13 is newly provided to form a gap between the back electrode substrate 3 and the upper surface of the shield case 95.

  That is, in the configuration of the ECM 90, since the acoustic hole 2c is provided on the circuit board 2 side, a space with a large volume between the circuit board 2 and the back electrode substrate 3 becomes the front air chamber S1, and the third spacer 13 A space with a small volume formed by providing the rear air chamber S2.

Next, a configuration in which the ECM 90 is mounted on a main circuit board 100 such as a mobile phone will be described.
As shown in FIG. 12, an acoustic hole 100a is also formed in the main circuit board 100 of a mobile phone or the like, and the bottom surface of the main circuit board 100 is placed with the acoustic hole 2c of the ECM 90 aligned with the acoustic hole 100a of the main circuit board 100. The output electrode 2b is attached to the side by soldering.

Next, the operation of the ECM 90 having the above configuration will be described.
When the vibrating membrane 7 is displaced from the upper surface side of the main circuit board 100 by the air vibration of the acoustic input signal Ps inputted through the acoustic hole 100a of the main circuit board 100 and the acoustic hole 2c of the ECM 90, the capacitor is The displacement is converted into an electric signal, and the electric signal is guided from the conductive diaphragm supporting frame 6a to each circuit board 2 via each connection electrode (not shown) and processed by the integrated circuit 11, and then the circuit board 2 Is output from the output electrode 2b provided on the lower surface of the substrate. The through-hole 3b formed in the back electrode substrate 3 and the presence of a gap formed between the back electrode substrate 3 and the upper surface of the shield case 95 by the newly provided third spacer 13 cause the vibration film 7 to Vibration operation is performed.

  According to the above configuration, since the ECM 90 is attached to the lower surface side of the main circuit board 100 such as a mobile phone, the distance between the case of the mobile phone and the main circuit board 100 only ensures the passage of the acoustic input signal Ps. It is sufficient if there is a gap, and the distance between the case of the mobile phone and the main circuit board 100 can be remarkably narrowed compared to the ECM 80 shown in FIG. 11, which is effective for reducing the size and thickness of the mobile phone or the like. .

JP 2003-78997 A JP-A-2005-192180

  In the conventional ECM described above, in the case of the ECM 80 shown in FIG. 11, a large volume space between the back electrode substrate 3 and the circuit board 2 can be used as the rear chamber S2, and therefore the acoustic characteristics are good. However, when it is mounted on the main circuit board 100 of a mobile phone or the like, the distance between the case of the mobile phone or the like and the main circuit board 100 needs to be wider than the height of the ECM 80. There are problems that hinder.

  Further, in the case of the ECM 90 shown in FIG. 12, the distance between the case of the mobile phone and the main circuit board 100 can be remarkably reduced, which is effective for reducing the size and thickness of the mobile phone or the like. As a result, the space between the circuit board 2 and the circuit board 2 having a large volume is used as the front air chamber S1, and the space having a small volume formed by providing the third spacer 13 becomes the rear air chamber S2. There is a problem that the rear air chamber S2 having a size for sufficiently securing the vibration operation cannot be obtained, resulting in insufficient acoustic characteristics. In addition, it is conceivable to increase the height of the third spacer 13 to secure the volume of the rear air chamber S2, but in this case, there is a problem that the shape of the ECM becomes large.

  The object of the present invention has been made in view of the above circumstances, and the basic configuration of the ECM is the same as that of the ECM 80, and further, an ECM 90 is provided by providing a connection board for attachment to the main circuit board on the upper surface side with the acoustic holes. It is possible to provide an ECM that can achieve the same mounting structure as the above, and can simultaneously achieve the acoustic characteristics and the small and thin mounting.

  The configuration of the ECM in the present invention for solving the above-described problem is a capacitor microphone in which a circuit board on which electronic components are mounted, a back electrode board in which an electret layer is formed on a back electrode, and a diaphragm unit are stacked. A connection board having an acoustic hole and an output electrode for electrical connection to the outside is provided above the diaphragm unit.

  According to the above configuration, by connecting the upper surface side of the ECM to the main circuit board using the connection board, it is possible to simultaneously achieve the acoustic characteristics and the small and thin mounting.

  The connection wiring to the outside including the power supply wiring is the output of the connection board through the input / output electrodes provided on the circuit board and the through holes or metal members provided in the back electrode board, the spacer, the vibration membrane unit, etc. It is connected to an electrode.

  The vibrating membrane unit is formed by attaching a vibrating membrane to a ring-shaped electrode formed on a printed circuit board.

  The printed circuit board constituting the vibration membrane unit is a connection board.

  The printed circuit board constituting the diaphragm unit is a gap spacer that regulates a gap between the back electrode substrate and the diaphragm.

  As described above, according to the present invention, by connecting the upper surface side of the ECM to the main circuit board using the connection board, it is possible to simultaneously achieve the acoustic characteristics and the small and thin mounting.

  The configuration of the ECM according to the first embodiment of the present invention will be described below with reference to FIGS. 1 is a cross-sectional view of the completed ECM, FIG. 2 is a cross-sectional view showing a state in which the ECM shown in FIG. 1 is attached to the main circuit board, and FIG. 3 is a perspective view of a collective board of each element constituting the ECM shown in FIG. 4 is a perspective view of a set ECM obtained by stacking and integrating each set substrate shown in FIG. 3, FIG. 5A is a perspective view of an ECM capsule obtained by dividing the set ECM, and FIG. 5B is a shield to the ECM capsule. It is a perspective view of completed ECM which attached the case.

Next, a specific configuration of the ECM according to the first embodiment of the present invention will be described with reference to FIGS. In FIG. 1 and FIG. 2, the same elements as those of the conventional ECM 80 and ECM 90 shown in FIG. 11 and FIG.
In FIG. 1, 10 is an ECM, and the basic configuration is the same as the ECM 80 of FIG. That is, the circuit board 2 is formed of an insulating substrate, and the connection wiring 2a and the input / output electrode 2c are formed on the upper surface side. The connection wiring 2a and the input / output electrode 2c pass through the through hole 2d and the routing wiring 2e. Connected.

  An integrated circuit 11 and an electronic element 12, which are electronic components, are mounted on the connection wiring 2 a, and an input / output electrode 2 c includes an input electrode for inputting a vibration detection signal from the power supply terminal and the vibration film 7, and the integrated circuit 11. An output electrode for outputting the processed acoustic signal is disposed on a part of the circuit board 2 and is a land-shaped electrode.

  The first spacer 8 and the back electrode substrate 3 disposed on the upper surface of the circuit board 2 are provided with a through hole 8 d and a through hole 3 d at the position of the input / output electrode 2 c of the circuit board 2. The second spacer 9, which is a gap spacer disposed on the upper surface of the back electrode substrate 3, is composed of an FPC (flexible printed circuit). Similarly, a through hole is formed at the position of the input / output electrode 2 c of the circuit substrate 2. 9d is provided. Further, a back electrode 4 made of an electrode film is formed on the top surface side of the back electrode substrate 3, and an electret layer 5 is formed on the top surface of the back electrode 4, and penetrates outside the back electrode 4 and the electret layer 5. A hole 3b is formed.

  The connection board 1 is composed of a double-sided printed board, and an output electrode 1b, a ground electrode 1gd, and an acoustic hole 1a are provided on the upper surface side. On the lower surface side, a connection electrode 1e is provided at a position corresponding to the input / output electrode 2c of the circuit board 2. The connection electrode 1e is connected to the output electrode 1b through the through hole 1d, and the second spacer 9, The back electrode substrate 3 and the first spacer 8 are connected to the input / output electrodes 2c of the circuit board 2 through through holes 9d, 3d, and 8d, respectively.

Further, a ring-shaped electrode 1g is formed in a range surrounding the back electrode 4 of the back electrode substrate 3 on the lower surface side of the connection substrate 1, and the conductive vibration film 7 is fixed to the ring-shaped electrode 1g to be integrated. Has been.
The ring-shaped electrode 1g is connected to the ground electrode 1gd through the through hole 1d, and through the through holes 9d, 3d, and 8d provided in the second spacer 9, the back electrode substrate 3, and the first spacer 8, respectively. The input / output electrode 2c of the circuit board 2 is connected.

  That is, in this embodiment, the connection substrate 1 is used as a diaphragm support frame, and the diaphragm 7 is fixed and integrated with the ring-shaped electrode 1g to constitute a diaphragm unit. The circuit board 2 and the connection board 1 are electrically connected to the first spacer 8, the back electrode board 3, the second spacer 9, and the through holes 8d, 3d, 9d and 1d provided in the connection board 1, respectively. They are connected via a connection electrode 1e and a ring-shaped electrode 1g provided on the substrate 1.

  FIG. 2 is a cross-sectional view showing a state in which the ECM 10 shown in FIG. 1 is attached to the main circuit board 100, and the ECM 10 is provided on the lower surface side of the main circuit board 100 having the acoustic holes 100a as in the mounting structure of the ECM 90 shown in FIG. In a state where the acoustic hole 1a of the connection board 1 provided in the ECM 10 is aligned with the acoustic hole 100a of the main circuit board 100, the output electrode 1b and the wiring pattern 110 provided on the lower surface side of the main circuit board 100 are provided. The ground electrode 1gd is attached by soldering.

Next, the operation of the ECM 10 will be described.
The acoustic input signal Ps input from the upper surface side of the main circuit board 100 through the acoustic hole 100a of the main circuit board 100 and the acoustic hole 1a of the ECM 10 is a connection board formed by the ring-shaped electrode 1g of the connection board 1. 1 and the diaphragm 7 are guided to the front air chamber S1. When the vibration film 7 is displaced by the air vibration of the acoustic input signal Ps, the capacitor converts the displacement into an electric signal. The electric signal is transmitted from the conductive vibration film 7 and the ring electrode 1g to the second spacer. 9, the back electrode substrate 3 and the first spacer 8 are led to the input / output electrodes 2c of the circuit board 2 through through holes 9d, 3d and 8d.

  Then, this electric signal is processed by the integrated circuit 11 and then the input / output electrode 2c of the circuit board 2 through the first spacer 8, the back electrode substrate 3, the second spacer 9, and the through holes 8d, 3d provided in the connection substrate 1, respectively. , 9d, 1d and the connection electrode 1e, the signal is output from the output electrode 1b of the connection board 1 to the main circuit board 100. The presence of the large volume rear air chamber S2 penetrated by the through-hole 3b formed in the back electrode substrate 3 makes the operation of the vibrating membrane 7 smooth and ensures acoustic characteristics.

  As described above, the ECM 10 of the present invention enables the input of the acoustic input signal Ps from the main circuit board side as in the conventional ECM 90 by providing the connection substrate 1 on the vibration film 7, so that the ECM 10 of the present invention is small-sized such as a cellular phone. Since the rear air chamber S2 having a large volume can be obtained by making the arrangement of each element the same as that of the conventional ECM80, it is possible to reduce the thickness of the mounting structure. The efficiency of the characteristics can be achieved at the same time.

  Next, a manufacturing method of the ECM 10 according to the present invention using a collective substrate will be described with reference to FIGS. FIG. 3 is an exploded perspective view of each collective substrate showing a manufacturing method of the ECM 10 using the collective substrate. In FIG. 3, the collective circuit substrate 2 </ b> L that is the collective substrate of the circuit substrate 2 and the collective substrate that is the collective substrate of the first spacer 8. 1 spacer 8L, collective back electrode substrate 3L that is a collective substrate of back electrode substrate 3, collective second spacer 9L that is a collective substrate of second spacer 9, and collective connection substrate 1L that is a collective substrate of connection substrate 1 are sequentially laminated. Each of the collective substrates has the same size.

Next, the configuration of each collective substrate will be described.
That is, the circuit board 2 is formed on the collective circuit board 2L, and the integrated circuit 11 and the electronic element 12 are mounted on the circuit board 2 and a plurality of input / output electrodes 2c are formed. A plurality of circuit boards 2 are provided on the collective circuit board 2L as shown in FIG. A plurality of first spacers 8 are formed in the aggregate first spacer 8L, and each first spacer 8 is formed with an opening 8a and a plurality of through holes 8d that constitute the rear air chamber S2. A plurality of back electrode substrates 3 are formed on the collective back electrode substrate 3L. Each back electrode substrate 3 is provided with a back electrode 4 and an electret layer 5, and further includes a through hole 3b and a plurality of through holes 3d. Is formed.

Similarly, a plurality of second spacers 9 are formed in the aggregated second spacer 9L, and each second spacer 9 is formed with an opening 9a and a plurality of through holes 9d constituting the rear air chamber S2. A plurality of connection substrates 1 are formed on the collective connection substrate 1L, and an acoustic hole 1a, a plurality of output electrodes 1b, and a ground electrode 1gd are formed on each connection substrate 1. Although not visible in the drawings, the diaphragm 7 is fixed to the ring electrode 1g provided on the lower surface side of each connection substrate 1 to constitute a diaphragm unit. The above is the process of forming each element as a collective substrate.
A frame shape indicated by a dotted line on each collective substrate indicates an outer shape when a single ECM capsule 10b is formed by cutting in a cutting process described later.

  FIG. 3 shows an example in which nine circuit boards 2 are formed on the collective circuit board 2L as an example in order to show that a plurality of elements are formed on each collective board. More elements are formed simultaneously.

  FIG. 4 is a perspective view of the collective ECM 10L, and shows a state in which the collective substrates shown in FIG. 4 are stacked and integrated. In other words, the collective circuit board 2L, the collective first spacer 8L, the collective back electrode substrate 3L, the collective second spacer 9L, and the collective connection board 1L are laminated and bonded together to form the collective ECM 10L. Further, when stacking and integrating the respective aggregate substrates, the positions of the through holes of the respective aggregate substrates are made to coincide with each other and are electrically connected to each other by a conductive paste.

  FIG. 5A shows a state in which the set ECM 10L is divided by a cutting method such as dicing to create a single ECM capsule 10b. Further, FIG. 5B shows a state in which the ECM 10 is completed by storing the ECM capsule 10 b in the shield case 15.

  Next, the configuration of the ECM according to the second embodiment of the present invention will be described with reference to FIGS. 6 is a cross-sectional view of the completed ECM. The same elements as those of the ECM 10 shown in FIG.

  The ECM 20 in FIG. 6 has the same basic configuration as the ECM 10 shown in FIG. 1, and the difference from the ECM 1 is the configuration of a gap spacer. That is, the ECM 10 uses the second spacer 9 made of FPC as the gap spacer, whereas the ECM 20 uses the second spacer 19 made of a metal plate as the gap spacer. That is, the second spacer 19 in the ECM 20 is provided with the metal electrode 19 d at a position corresponding to the through hole 9 d of the second spacer 9 in the ECM 10, and the back electrode substrate 3 and the connection substrate 1 are electrically connected. It is.

  FIG. 7 is a partially enlarged view of the aggregate second spacer 19L and corresponds to the aggregate second spacer 9L shown in FIG. FIG. 8 is a perspective view of the second spacer 19 cut and separated from the aggregate second spacer 19L. FIG. 7 shows one of a plurality of second spacers 19 formed on a second assembled spacer 19L made of a large metal plate. The second spacer 19 indicated by a dotted line includes a rear air chamber. Openings 19e and 19f for forming the opening 19a constituting the S2 and the metal electrode 19d are provided. The openings 19e and 19f are provided across the cutting region indicated by the dotted line, and the metal electrode 19d is separated from the main body of the second spacer 19 as shown in FIG. 8 by cutting the laminate shown in FIG. It will function as an independent connection electrode.

  The ECM 20 having the above configuration is advantageous in reducing the cost of the ECM because an inexpensive metal plate is used instead of an expensive FPC as a gap spacer. The operation of the ECM 20 is the same as that of the ECM 10.

  Next, the configuration of the ECM according to the third embodiment of the present invention will be described with reference to FIG. FIG. 9 is a sectional view of the completed ECM. The same elements as those of the ECM 10 shown in FIG. The ECM 30 in FIG. 9 has the same basic configuration as the ECM 10 shown in FIG. 1, and the difference is that a multilayer substrate is used as the connection substrate 1 to increase the degree of freedom of electrode wiring.

  In the ECM 30, a laminated substrate is used as the connection substrate 1, and the arrangement position of the output electrode 1b can be arranged at an arbitrary position by the internal wiring 1f of the laminated substrate. Further, a shield electrode 1h connected to the ground electrode 1gd is provided on the lower surface side of the connection substrate 1 to prevent electromagnetic noise from the outside to the ECM.

Next, the configuration of the ECM according to the fourth embodiment of the present invention will be described with reference to FIG.
FIG. 10 is a cross-sectional view of the ECM according to the fourth embodiment of the present invention. The same elements as those of the ECM 10 shown in FIG. The ECM 40 in FIG. 10 is different from the ECM 10 shown in FIG. 1 in that the circuit board 2 is omitted, and instead, a part of the FPC constituting the second spacer 9 is bent through the through-hole 13b provided in the back electrode substrate 13, The circuit board portion 9 f extends into the space formed by the one spacer 18.

  The integrated circuit 11 is mounted on the extended circuit board portion 9f. Accordingly, since the electrical connection between the integrated circuit 11 and the vibration film 7 or the connection substrate 1 is directly performed by FPC, the back electrode substrate 13 and the first spacer 18 are not provided with through holes.

  Since the circuit board 2 is omitted in the configuration of the ECM 40, it is possible to reduce the thickness of the ECM, and at the same time, it is not necessary to provide a through hole in the back electrode substrate 13 and the first spacer 18. The substrate 13 can be a single-sided printed circuit board, and the first spacer 18 can be a simple frame member, which can significantly reduce the cost.

  As described above, the ECM according to the present invention can be attached to the lower surface side of a main circuit board such as a mobile phone by providing a connection board above the diaphragm, and has a conventional acoustic hole provided above the diaphragm. Similar to the ECM, an ECM having good acoustic characteristics can be provided by a large volume rear air chamber.

In each of the above embodiments, the example in which the diaphragm unit is configured by adhering and fixing the diaphragm to the ring-shaped electrode provided on the connection board is not limited thereto, but the second spacer is configured. A vibrating membrane unit may be configured by forming a ring-shaped electrode on the FPC and bonding and fixing a diaphragm to the ring-shaped electrode.
In each embodiment, the example of the diaphragm having a rectangular shape is mainly shown. However, the present invention is not limited to this example, and can naturally be applied to a diaphragm having a circular shape or an elliptical shape. is there.

It is sectional drawing of ECM10 in 1st Embodiment of this invention. It is sectional drawing which shows the state which attached ECM10 shown in FIG. 1 to the main circuit board. FIG. 2 is a developed perspective view of each collective substrate showing a manufacturing method of the ECM 10 shown in FIG. 1 using the collective substrate. FIG. 4 is a perspective view of an aggregate ECM 10L in which the aggregate substrates shown in FIG. 3 are stacked and integrated. 5A is a perspective view of a single ECM capsule 10b created by dividing the set ECM 10L, and FIG. 5B is a perspective view of a completed ECM 10 in which the ECM capsule 10b is housed in a shield case 15. FIG. is there. It is sectional drawing of ECM20 in 2nd Embodiment of this invention. FIG. 4 is a partially enlarged view of an aggregate second spacer 19L in the ECM 20, corresponding to the aggregate second spacer 9L shown in FIG. FIG. 8 is a perspective view of the second spacer 19 cut and separated from the assembled second spacer 19L of FIG. It is sectional drawing of ECM30 in 3rd Embodiment of this invention. It is sectional drawing of ECM40 in 4th Embodiment of this invention. It is sectional drawing of ECM80 in a prior art example. It is sectional drawing of ECM90 in a prior art example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Connection board | substrate 1a Acoustic hole 1b Output electrode 2 Circuit board 3, 13 Back electrode board 4 Back electrode 5 Electret layer 7 Vibrating membrane 8, 18 1st spacer 9 2nd spacer 10, 20, 30, 40, 80, 90 ECM
10b ECM capsule 10L Collective ECM
DESCRIPTION OF SYMBOLS 11 Integrated circuit 12 Electronic element 15 Shield case 100 Main circuit board S1 Front air chamber S2 Rear air chamber

Claims (5)

  In a condenser microphone in which a circuit board on which electronic components are mounted, a back electrode board in which an electret layer is formed on the back electrode, and a diaphragm unit are laminated, an electrical connection between the acoustic hole and the outside is provided above the diaphragm unit. A capacitor microphone, characterized in that a connection substrate having an output electrode for performing the operation is provided.   The connection wiring to the outside including the power supply wiring is the output of the connection board through the input / output electrodes provided on the circuit board and the through holes or metal members provided in the back electrode board, the spacer, the vibration membrane unit, etc. The condenser microphone according to claim 1 connected to an electrode.   The condenser microphone according to claim 1, wherein the vibration film unit is formed by fixing a vibration film to a ring-shaped electrode formed on a printed circuit board.   4. The condenser microphone according to claim 3, wherein the printed circuit board constituting the vibration membrane unit is a connection substrate. 4. The condenser microphone according to claim 3, wherein the printed circuit board constituting the diaphragm unit is a gap spacer that regulates a gap between the back electrode substrate and the diaphragm.

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