1A
BACKGROUND OF THE INVENTION
Field of the Invention
The present invention relates to microphone modules for receiving and
detecting sounds. The present invention also relates to mounting structures for
installing microphone modules in portable electronic devices.
This application claims priority on Japanese Patent Application No.
2006-244268, the content of which is incorporated herein by reference.
Description of the Related Art
Conventionally-known portable electronic devices such as portable telephones
and cellular phones are equipped with microphone modules for receiving and detecting
sounds. For example, U.S. Patent Application Publication No. 2006/0116180 teaches
an acoustic transducer module, i.e., a miniature silicon condenser microphone module
adapted to micro-electromechanical systems (MEMS). This type of the microphone
module includes an external connection terminal and a sound hole to enter sound, both
of which are formed on the exterior surface of a housing having a hollow cavity. This
microphone module is mounted on a mount portion of a circuit board included in the
housing of a portable electronic device. The external connection terminal of the
microphone module is brought into contact with a connection pad formed on the
mount portion, thus establishing an electrical connection between the circuit board and
the microphone module.
When the conventionally-known microphone module is installed in the
portable electronic device, it is necessary to precisely mount the microphone module

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on the mount portion of the circuit board in such a way that a sound port of the
housing of the portable electronic device, which allows the entry of sound, is
positioned opposite to the sound hole of the housing of the microphone module. For
this reason, it is necessary to appropriately change the positions of the external
connection terminal and sound hole formed on the exterior surface of the housing of
the microphone module in consideration of the position of the mount portion of the
circuit board in relation to the sound port of the housing of the portable electronic
device.
When the mount portion of the circuit board is positioned opposite to the
sound port of the portable electronic device, it is necessary to form the sound hole and
the external connection terminal on the opposite surfaces positioned opposite to each
other within the exterior of the housing of the microphone module.
When the prescribed surface of the circuit board opposite to its mount portion
is positioned opposite to the sound port of the portable electronic device, it is
necessary to form both the sound hole and the external connection terminal on the
same surface within the exterior of the housing of the microphone module. In this
case, it is necessary to form a through-hole running through the circuit board in its
thickness direction, via which the sound hole of the microphone module directly faces
the sound port of the portable electronic device.
As described above, the conventionally-known microphone module is
troublesome because it is necessary to change the positions of the external connection
terminal and sound hole within the exterior in response to the position of the mount
portion of the circuit board, which is positioned relative to the sound port of the
portable electronic device. This reduces the degree of freedom in mounting the
microphone module on the mount portion of the circuit board.

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Since the conventionally-known microphone module is designed to suit the
mount portion of the circuit board, the height of the microphone module substantially
matches the projection height realized by the microphone module projecting from the
mount portion of the circuit board. This causes a limitation for reducing the size of
the housing in which the microphone module is mounted on the circuit board.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a microphone module and its
mounting structure, by which the degree of freedom is increased with respect to the
mounting operation of the microphone module installed in the portable electronic
device.
It is another object of the present invention to provide a portable electronic
device having a reduced thickness, which realizes stable installation of the microphone
module by use of the mounting structure.
In a first aspect of the present invention, a microphone module includes a
housing having a hollow cavity and a sound hole, via which the hollow cavity
communicates with the exterior, a microphone chip for detecting sound inside of the
hollow cavity, a plurality of external connection terminals that are electrically
connected to the microphone chip, and a plurality of extended portions that are
horizontally extended from both ends of the housing in the direction perpendicular to
the opening direction of the sound hole, wherein the external connection terminals are
each elongated onto one of surfaces and backsides of the extended portions, and
wherein the housing partially projects from the surfaces of the extended portions.
The housing of the microphone module is inserted into a recess or
through-hole of the circuit board and is then mounted on the mount portion of the

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circuit board, wherein the depth of the recess is larger than the projection height of the
housing that projects from the surfaces of the extended portions. Herein, the housing
is inserted into the through-hole in such a way that the surfaces of the extended
portions come in contact with the mount portion of the circuit board in the periphery of
the through-hole, whereby the external connection terminals formed on the surfaces of
the extended portions are brought into contact with connection pads that are formed in
the periphery of the through-hole on the mount portion of the circuit board, thus
reliably establishing an electrical connection between the microphone module and the
circuit board.
Since the housing is partially held inside the through-hole of the circuit board,
it is possible to reduce the projection height of the microphone module; it is possible to
avoid the positional deviation of the microphone module relative to the circuit board;
and it is possible to improve the mounting strength (or packaging strength) of the
microphone module mounted on the circuit board.
In the above, the external connection terminals are each elongated onto the
backside of the housing, which is positioned opposite to the surfaces of the extended
portions. Since the external connection terminals are exposed on both of the surfaces
and backsides of the extended portions, it is possible to reliably mount the microphone
module without changing the positions of the external connection terminals in such a
way that the surfaces of the extended portions are positioned opposite to the mount
portion of the circuit board, alternatively, in such a way that the backsides of the
extended portions are positioned opposite to the mount portion of the circuit board.
In addition, even when the sound hole is opened in either the surface or backside of the
housing, it is possible to reliably mount the microphone module on the circuit board in
such a way that the sound hole is opened above the mount portion, or the sound hole is

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opened above the opposite surface of the circuit board opposite to the mount portion.
When the sound hole is formed at a height above the surfaces of the extended
portions of the housing, a ring-shaped anti-sound-leak gasket is attached to the
microphone module before the microphone module is mounted on the circuit board in
such a way that the backsides of the extended portions are positioned opposite to the
mount portion of the circuit board. That is, when the housing, which partially
projects from the surfaces of the extended portions, is engaged inside of the
ring-shaped anti-sound-leak gasket, the terminal portion of the anti-sound-leak gasket
comes in contact with the surfaces of the extended portions; hence, it is possible to
easily establish positioning of the anti-sound-leak gasket relative to the microphone
module. This eliminates the necessity of attaching the anti-sound-leak gasket to the
microphone module after the microphone module is mounted on the circuit board;
hence, it is possible to reliably maintain an electrical connection between the
microphone module and the circuit board.
In addition, the housing is constituted of a substrate for fixedly mounting the
microphone chip on the surface thereof and a cover member that covers the surface of
the substrate so as to form the hollow cavity, wherein the extended portions are formed
using the substrate and are extended externally from the cover member. Furthermore,
the extended portions are formed using a plurality of leads, each having a conductivity,
which serve as the external connection terminals, wherein the housing is formed using
a resin mold for sealing the leads.
Alternatively, the microphone module is basically constituted of a main body
and a support for mounting and supporting the main body. The main body is
constituted of a housing having a hollow cavity, a microphone chip that is arranged
inside of the hollow cavity so as to detect sound, and a plurality of external connection

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terminals that are each electrically connected to the microphone chip. The housing
has a sound hole for communicating the hollow cavity to the exterior, and the external
connection terminals are each elongated onto the backside of the housing in the
direction perpendicular to the opening direction of the sound hole. The support is
constituted of a mount portion that is positioned opposite to the backside of the
housing so as to mount the main body, a plurality of extended portions that are
horizontally extended externally of the mount portion in the direction perpendicular to
the opening direction of the sound hole, and a plurality of intermediate connection
terminals that are elongated from the mount portion to the extended portions. The
intermediate connection terminals are elongated onto the surfaces of the extended
portions lying in parallel with the mount portion.
In the above, the main body of the microphone module is fixed to the support
such that the backside of the housing is directed to the mount portion of the support,
wherein the external connection terminals exposed on the backside of the housing are
electrically connected to the intermediate connection terminals formed on the mount
portion of the support. The intermediate connection terminals are each elongated
toward the surfaces of the extended portions; this makes is possible to reliably mount
the microphone module on the circuit board by simply directing the surface of the
housing to the mount portion. Even when the main body of the microphone module
is removed from the support, it is possible to reliably mount the main body on the
circuit board by simply directing the backside of the housing toward the mount portion
of the circuit board. This makes it possible to easily mount the microphone module
on the circuit board by changing the direction of the housing relative to the mount
portion of the circuit board without changing the positions of the external connection
terminals. Even when the sound hole is opened in either the surface or backside of

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the housing, it is possible to reliably mount the microphone module on the circuit
board such that the sound hole is opened above the mount portion of the circuit board
or above the opposite surface of the circuit board.
Moreover, the heights of the surfaces of the extended portions measured from
the mount portion are lower than the height of the main body mounted on the mount
portion of the support. Herein, the housing is inserted into the through-hole of the
circuit board such that the surfaces of the extended portions come in contact with the
mount portion of the circuit board in the periphery of the through-hole, wherein the
intermediate connection terminals formed on the surfaces of the extended portions are
brought into contact with the connection pads formed on the mount surface of the
circuit board in the periphery of the through-hole, thus electrically connecting the main
body of the microphone module to the circuit board.
In a second aspect of the present invention, the microphone module is
mounted on the mount portion of the circuit board by way of a mounting structure.
Herein, the microphone module includes a housing having a hollow cavity and a sound
hole for communicating the hollow cavity with the exterior, a microphone chip that is
arranged inside of the hollow cavity so as to detect sound, a plurality of extended
portions that are horizontally extended from the housing in the direction perpendicular
to the opening direction of the sound hole, and a plurality of connection terminals that
are formed in the extended portions and are electrically connected to the microphone
chip. When the housing is inserted into a hole running through the mount portion of
the circuit board, the extended portions come in contact with the mount portion so that
the connection terminals come in contact with the connection pads formed on the
mount portion of the circuit board, thus establishing an electrical connection between
the microphone module and the circuit board.

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In a third aspect of the present invention, the microphone module is mounted
on the mount portion of the circuit board incorporated in the housing of a portable
electronic device. When the housing is inserted into a hole running through the
mount portion of the circuit board, the extended portions come in contact with the
mount portion so that the connection terminals come in contact with the connection
pads formed on the mount portion of the circuit board, thus establishing an electrical
connection between the microphone module and the circuit board.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other objects, aspects, and embodiments of the present invention
will be described in more detail with reference to the following drawings, in which:
FIG. 1 is a cross-sectional view showing the constitution of a microphone
module in accordance with a first embodiment of the present invention;
FIG. 2 is a cross-sectional view showing a portable electronic device equipped
with the microphone module;
FIG. 3 is a cross-sectional view showing another portable electronic device
equipped with the microphone module;
FIG. 4 is a cross-sectional view showing a first variation of the portable
electronic device shown in FIG. 2;
FIG. 5 is a cross-sectional view showing a second variation of the portable
electronic device shown in FIG. 2;
FIG. 6 is a cross-sectional view showing the constitution of a microphone
module in accordance with a second embodiment of the present invention;
FIG. 7 is a perspective view showing the structure of a support for mounting
and supporting the microphone module shown in FIG. 6;

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FIG. 8 is a cross-sectional view showing the constitution of a portable
electronic device incorporating the microphone module of FIG. 6 by way of the
support shown in FIG. 7;
FIG. 9 is a cross-sectional view showing the constitution of another portable
electronic device incorporating the microphone module of FIG. 6;
FIG. 10 is a cross-sectional view showing a first variation of the portable
electronic device shown in FIG. 8; and
FIG. 11 is a cross-sectional view showing a second variation of the portable
electronic device shown in FIG. 8.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention will be described in further detail by way of examples
with reference to the accompanying drawings.
1. First Embodiment
A microphone module 1 according to a first embodiment of the present
invention will be described with reference to FIGS. 1 to 3.
As shown in FIGS. 2 and 3, the microphone module 1 is designed to suit
housings 5 and 6 of portable electronic devices (e.g., portable telephones) respectively.
Specifically, the microphone module 1 is designed in a shape, which can be mounted
on mount portions 9 and 10 of circuit boards 7 and 8 incorporated in the housings 5
and 6 of the portable electronic devices 3 and 4 respectively.
As shown in FIG. 1, the microphone module 1 includes a substrate 11 having
a rectangular shape in plan view, a microphone chip 15 and a control circuit chip 17
fixed onto a surface 13 of the substrate 11, and a cover member 19, which covers a
part of the surface 13 of the substrate 11 including the microphone chip 15 and the

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control circuit chip 17 so as to form a hollow cavity SI together with the substrate 11.
Herein, peripheral portions (or extended portions) of the substrate 11 are horizontally
extended in opposite directions externally from the side walls of the cover member 19.
The substrate 11 has a multilayered wiring substrate, in which a plurality of
external connection terminals 21 are formed on the substrate 11 so as to electrically
connect the microphone chip 15 and the control circuit chip 17 to the circuit board 7 or
8 (see FIGS. 2 and 3). Each of the external connection terminals 21 are exposed on
the surface 13 and a backside 14 of the substrate 11. Specifically, a first portion 21A
of the external connection terminal 21, which is exposed on the surface 13 of the
substrate 11, is elongated horizontally from the inside to the outside of the cavity SI.
A second portion 21B of the external connection terminal 21, which is exposed on the
backside 14 of the substrate 11, is positioned inward with respect to the extended
portions of the substrate 11 extended externally from the side walls of the cover
member 19.
A sound hole 25, which allows the cavity SI to communicate with the exterior,
is formed at a prescribed position of a top portion 23 of the cover member 19 that is
positioned opposite to the surface 13 of the substrate 11. The opening direction A of
the sound hole 25 lies vertical to the surface 13 of the substrate 11.
The microphone chip 15 is constituted such that a diaphragm 29 covers an
inner hole 27a of a ring-shaped support 27. The diaphragm 29 detects sound by way
of vibration; hence, the microphone chip 15 forms a sound pressure sensor that
converts vibration of the diaphragm 29 into electric signals.
The microphone chip 15 is fixed on the surface 13 of the substrate 11 by use
of a die bonding material (not shown) in such a way that the diaphragm 29 is
positioned opposite to the surface 13 of the substrate 11 via the inner hole 27a.

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The control circuit chip 17 drives and controls the microphone chip 15.
Specifically, the control circuit chip 17 includes an amplifier for amplifying electric
signals from the microphone chip 15, a digital signal processor (DSP) for processing
electric signals in form of digital signals, and an analog-to-digital (A/D) converter.
Similar to the microphone chip 15, the control circuit chip 17 is fixed on the surface 13
of the substrate 11 by use of the die bond material (not shown).
The control circuit chip 17 is electrically connected to the microphone chip 15
via a first wire 31, while it is also electrically connected to the first portion 21A of the
external connection terminal 21, which is exposed inside of the cavity SI, via a second
wire 33. This makes it possible to electrically connect the microphone chip 15 to the
external terminal 21.
In the microphone module 1 having the aforementioned constitution, a
housing 41 forming the cavity SI and the sound hole 25 is constituted of the cover
member 19 and the prescribed part of the substrate 11 covered with the cover member
19. The extended portions of the substrate 11, which are extended externally from
the side walls of the cover member 19, are defined as extended portions 43, which are
extended from the exterior of the housing 41 in horizontal directions perpendicular to
the opening direction A of the sound hole 25.
Therefore, the microphone module 1 has the extended portions 43, which are
reversely extended from both sides of the housing 41, whereby the housing 41
vertically projects from surfaces 13A of the extended portions 43, which correspond to
the surface 13 of the substrate 11. The external connection terminals 21 are vertically
elongated along the opening direction of the sound hole 25 from the surfaces 13A of
the extended portions 43 to the backside 14B of the housing 41, which is positioned
opposite to the surfaces 13A of the extended portions 43. In other words, the external

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connection terminal 21 does not exist in backsides 14A of the extended portions 43,
which correspond to the backside 14 of the substrate 11.
In the manufacturing of the microphone module 1, the microphone chip 15
and the control circuit chip 17 are fixed onto the surface 13 of the substrate 11 in
which the external connection terminals 21 are formed in advance; then, the
microphone chip 15 is electrically connected to the control circuit chip 17 via the first
wire 31, and the control circuit chip 17 is electrically connected to the external
connection terminal 21; thereafter, the cover member 19 having the sound hole 25 is
fixed onto the surface 13 of the substrate 11.
Next, the mounting structure of the microphone module 1, which is mounted
on the mount portion of the circuit board of the microphone module 1, as well as a
portable electronic device having the mounting structure will be described with
reference to FIGS. 2 and 3.
The housing 5 of the portable electronic device 3 shown in FIG. 2 has a sound
port 5a to allow the entry of sound, and the housing 6 of the portable electronic device
4 shown in FIG. 3 has a sound port 6a to allow the entry of sound. Herein, the
portable electronic device 3 has a mounting structure for mounting the microphone
module 1 on a mount portion 9 of a circuit board 7 at a prescribed position relative to
the sound port 5 a of the housing 5, and the portable electronic device 4 has a mounting
structure for mounting the microphone module 1 on a mount portion 10 of a circuit
board 8 at a prescribed position relative to the sound port 6a of the housing 6. These
mounting structures differ from each other depending upon the positioning of the
mount portions 9 and 10.
In the portable electronic device 3 shown in FIG. 2 in which a surface 45 of
the circuit board 7 positioned opposite to the mount portion 9 is directed to the sound

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port 5a of the housing 5, a through-hole 47 running through the circuit board 7 in its
thickness direction is formed in advance so as to allow the housing 41 to be inserted
therein. When the housing 41 is inserted into the through-hole 47 from the mount
portion 9, the surfaces 13A of the extended portions 43 come in contact with the mount
portion 9 in the periphery of the through-hole 47. Connection pads 49 are formed in
advance in connection with the mount portion 9 in the periphery of the through-hole
47; hence, the external connection terminals 21 exposed on the surfaces 13A of the
extended portions 43 come in contact with the connection pads 49 so as to establish an
electrical connection between the microphone module 1 and the circuit board 7. In
the above, the microphone module 1 is arranged in such a way that the sound hole 25
is opened upwardly relative to the surface 45 of the circuit board 7 and is directed to
the sound port 5 a of the housing 5 of the portable electronic device 3.
A ring-shaped anti-sound-leak gasket 51 is inserted between the sound hole
25 and the sound port 5a, whereby it prevents sound, which is introduced into the
housing 5 via the sound port 5a, from dispersing inside of the housing 5; thus, it is
possible to efficiently propagate sound into the cavity SI. The shape of the
anti-sound-leak gasket 51 is not necessarily limited to the ring shape but can be
arbitrarily designed in any shape suiting the shaping of the sound hole 25 and the
sound port 5 a.
In FIG. 2, the exterior of the top portion 23 of the microphone module 1
forming the sound hole 25 is placed substantially in the same plane as the surface 45 of
the circuit board 7; but this is not a restriction. For example, the top portion 43 of the
microphone module 1 can be placed at a position that is lower than the surface 45 of
the circuit board 7, or it can be placed at a position projecting from the surface 45 of
the circuit board 7.

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In the portable electronic device 4 shown in FIG. 3 in which the mount portion
10 of the circuit board 8 is positioned opposite to the sound port 6a of the housing 6, it
is unnecessary to form the through-hole 47, wherein the microphone module 1 is
mounted on the circuit board 8 under the condition in which the backside 14B of the
housing 41 is positioned opposite to the mount portion 10 of the circuit board 8 having
the connection pad 49. This makes it possible for the second portion 21B of the
external connection terminal 21, which is exposed on the backside 14B of the housing
41, to come in contact with the connection pad 49, thus establishing an electrical
connection between the microphone module 1 and the circuit board 8. The sound
hole 25 of the microphone module 1 is opened upwardly above the mount portion 10
of the circuit board 8 so as to directly face the sound port 6a of the housing 6.
In the above, a ring-shaped anti-sound-leak gasket 53 is not directly held
between the sound hole 25 of the microphone module 1 and the sound port 6a of the
housing 6 but is directly attached to the microphone module 1. That is, the housing
41 of the microphone module 1, which vertically projects from the surfaces 13A of the
extended portions 43 of the substrate 11, is inserted into the ring-shaped
anti-sound-leak gasket 53 so that the lower portion of the anti-sound-leak gasket 53 is
brought into contact with the surfaces 13 A of the extended portions 43 of the substrate
11. Herein, the interior of the anti-sound-leak gasket 53 is shaped to substantially
match the shape of the housing 41.
The aforementioned structure makes it easy to establish the prescribed
positioning between the microphone module 1 and the anti-sound-leak gasket 53.
Since the upper portion of the anti-sound-leak gasket 53 must be brought into contact
with an interior surface 6b of the housing 6, the upper portion of the anti-sound-leak
gasket 53 projects upwardly from the exterior of the top portion 23 of the housing 41

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when the microphone module 1 is fixed into the portable electronic device 4.
When the microphone module 1 is installed in the portable electronic device 3
by use of the aforementioned mounting structure shown in FIG. 2, the housing 41 is
inserted into and engaged with the through-hole 47 of the circuit board 7; hence, it is
possible to reduce the projection height of the microphone module 1 projecting from
the mount portion 9 of the circuit board 7. This prevents the microphone module 1
from disturbing parts of the portable electronic device 3 even when the circuit board 7
is arranged inside of the housing 5 of the portable electronic device 3; hence, it is
possible to easily increase the degree of freedom in designing the portable electronic
device 3. In addition, it is possible to easily reduce the thickness of the portable
electronic device 3 including the circuit board 7.
Due to the insertion of the housing 41 into the through-hole 47 of the circuit
board 7, it is possible to avoid the positional deviation of the microphone module 1
relative to the circuit board 7; hence, it is possible to improve the mounting strength
(or packaging strength) of the microphone module 1 mounted on the circuit board 7.
In the portable electronic device 4 shown in FIG. 3 in which the microphone
module 1 is mounted on the circuit board 8 in such a way that the backside 14B of the
housing 41 is positioned opposite to the mount portion 10 of the circuit board 8, it is
possible to attach the anti-sound-leak gasket 53 to the microphone module 1 in
advance before the microphone module 1 is mounted on the circuit board 8. In other
words, it is unnecessary to attach the anti-sound-leak gasket 53 to the microphone
module 1 after the microphone module 1 is mounted on the circuit board 8. Thus, it
is possible to maintain a reliable electrical connection between the microphone module
1 and the circuit board 8.
As described above, in the portable electronic device 3 shown in FIG. 2, the

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microphone module 1 is mounted on the circuit board 7 in such a way that surfaces
13A of the extended portions 43 are positioned opposite to the mount surface 9.
Alternatively, in the portable electronic device 4 shown in FIG. 3, the microphone
module 1 is mounted on the circuit board 8 in such a way that the backside 14B of the
housing 41 is positioned opposite to the mount portion 10. This improves the degree
of freedom in mounting the microphone module 1 on the circuit boards 7 and 8
respectively; hence, it is possible to further improve the degree of freedom in
designing the portable electronic devices 3 and 4.
The microphone module 1 is constituted of the substrate 11 and the cover
member 19, wherein the first portion 21A and the second portion 21B of the external
connection terminal 21, which is used to establish an electrical connection with the
circuit boards 7 and 8 respectively, are formed in connection with the substrate 11 only.
This makes it possible to produce the microphone module 1 with ease.
The first embodiment is designed such that the sound hole 25 is formed on the
top portion 23 of the cover member 19; but this is not a restriction. That is, it is
simply required that the housing 41 be constituted of at least a part of the substrate 11
and the cover member 19, and the opening direction of the sound hole 25 be
perpendicular to the extended portions 43 of the substrate 11. For this reason, the
portable electronic device 3 shown in FIG. 2 can be modified in a variety of ways.
FIG. 4 shows a first variation of the portable electronic device 3 incorporating
a microphone module 61, in which a sound hole 55 is formed to run through the
substrate 11 in its thickness direction so as to allow the cavity S1 to communicate the
exterior. In this case, the surfaces 13A of the extended portions 43 lie opposite to and
along the opening direction B of the sound hole 55.
In FIG. 4, the microphone module 61 having the sound hole 55, which is

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opened in the backside 14 of the substrate 11, is installed in the portable electronic
device 3 in such a way that the surfaces 13 A of the extended portions 43 are positioned
opposite to the mount portion 9 of the circuit board 7. Similar to the portable
electronic device 3 shown in FIG. 2, it is necessary to form the through-hole 47 for the
insertion of the housing 41 in the circuit board 7. When the microphone module 61 is
modified such that the backside 14 of the substrate 11 is positioned opposite to the
mount portion 9 of the circuit board 7, it is necessary to form another through-hole
(not shown) allowing the sound hole 55 to be opened with the exterior.
In the first embodiment, the external terminals 21 are formed on the backside
14B of the housing 41; but this is not a restriction. For example, the external
connection terminals 21 can be formed on the backside 14A of the extended portions
43; or they can be formed on the backsides 14A of the extended portions 43 as well as
the backside 14B of the substrate 11.
The external connection terminals 21, which are electrically connected to the
microphone chip 15, are not necessarily formed on the backsides 14A of the extended
portions 43 and the backside 14B of the substrate 11; that is, they can be formed on
only the surfaces 13A of the extended portions 43. This modification allows the
housing 41 to be reliably inserted into the through-hole 47 of the circuit board 17;
hence, it is possible to reduce the projection height of the microphone module 1 or 61,
which vertically projects from the mount portion 9 of the circuit board 7.
In the first embodiment, the microphone module 1 is constituted of the
substrate 11 and the cover member 9; but this is not a restriction. FIG. 5 shows a
second variation of the portable electronic device 3 incorporating a microphone
module 71, which is constituted of a resin mold 73, a cover board 75, and a plurality of
leads 77.

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The resin mold 73 is constituted of a bottom 79 having a rectangular shape in
plan view and a side wall 81 that projects vertically from the periphery of a surface
79a of the bottom 79. The microphone chip 15 and the control circuit chip 17 are
fixed onto the surface 79a of the bottom 79.
The cover board 75 is fixed to the upper end of the side wall 81 and is thus
positioned opposite to the surface 79a of the bottom 79. The cover board 75 joins the
resin mold 73 so as to form a hollow cavity S2. A sound hole 83 is formed to run
through the cover member 75 in its thickness direction so as to allow the cavity S2 to
communicate the exterior. The sound hole 83 has an opening direction C
perpendicular to the surface 79a of the bottom 79.
The leads 77 are each composed of a metal material having conductivity.
The leads 77 are sealed with the resin mold 73 in such a way that the first ends thereof
are exposed in the cavity S2, and the second ends thereof are extended from the side
portion of the mold resin 73.
The control circuit chip 17 is electrically connected to the first end of the lead
77 via the second wire 33, thus allowing the microphone chip 15 to be electrically
connected to the lead 77. In the microphone module 71, the prescribed portions of
the resin mold 73 project externally from surfaces 77A at the second ends of the leads
77, while backsides 77B of the second ends of the leads 77 are formed in substantially
the same plane as a backside 79b of the resin mold 73.
In the aforementioned constitution, a housing 85 including the cavity S2 and
the sound hole 83 is formed using the resin mold 73 and the cover board 75.
Extended portions 87, which are extended from the housing 85 in a horizontal
direction perpendicular to the opening direction C of the sound hole 83, are formed
using the extended portions of the leads 77, which are extended from the resin mold 73.

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The leads 77 serve as external connection terminals that are electrically connected to
the microphone chip 15.
Similar to the microphone module 1, the microphone module 71 having the
aforementioned constitution can be mounted on the mount portion 9 of the circuit
board 7 that is positioned relative to the sound port 5a of the housing 5.
For example, when the opposite surface 45 of the circuit board 7 is directed
toward the sound port 5 a of the housing 5, the housing 85 is inserted into the
through-hole 47 of the circuit board 7 from the mount portion 9, so that the surfaces
77 A of the leads 77, which are extended from the resin mold 73, come in contact with
the connection pads 49 formed on the periphery of the through-hole 47, thus
establishing electric connection with the circuit board 7. In this state, the microphone
module 71 is installed in the portable electronic device such that the sound hole 83 is
opened upwardly above the opposite surface 45 of the circuit board 7 so as to directly
face the sound port 5 a of the housing 5.
The microphone module 71 offers effects similar to those of the microphone
modules 41 and 61. In addition, it is possible to easily produce the microphone
module 71, which is formed by sealing the leads 77 (serving as the external connection
terminals and the extended portions 87) with the resin mold 73.
In the microphone modules 1, 61 and 71, the housings 41 and 85 project from
the surfaces 13 A and 77 A of the extended portions 43 and 87 respectively, whereas
they can project from the backsides 14A and 77B of the extended portions 43 and 87
respectively.
2. Second Embodiment
Next, a microphone module 101 according to a second embodiment of the
present invention will be described in detail with reference to FIGS. 6 to 9, wherein

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parts identical to those of the microphone module 1 as well as parts identical to those
of the portable electronic devices 3 and 4 are designated by the same reference
numerals; hence, the descriptions thereof will be omitted as necessary.
As shown in FIG. 6, the microphone module 101 is constituted of a main body
103 and a support 105 for mounting and supporting the main body 103.
The main body 103 of the microphone module 101 is constituted of a
substrate 107 having a rectangular shape in plan view, the microphone chip 15 and the
control circuit chip 17 both fixed onto a surface 107a of the substrate 107, and a cover
member 109 that entirely covers the surface 107a of the substrate 107 including the
microphone chip 15 and the control circuit chip 17 so as to form a hollow cavity S3
with the substrate 107.
The substrate 107 is a multilayered wiring substrate, in which a plurality of
external connection terminals 111 are formed to electrically connect the microphone
chip 15 and the control circuit chip 17, which are arranged inside of the cavity S3, to
the circuit boards 7 and 8 respectively (see FIGS. 8 and 9). The external connection
terminals 111 are each exposed on both of the surface 107a and a backside 107b of the
substrate 107, wherein the prescribed portions of the external connection terminals 111
exposed on the surface 107a of the substrate 107 are exposed inside of the cavity S3.
A sound hole 115 allowing the cavity S3 to communicate the exterior is
formed at a prescribed position of atop portion 113 of the cover member 109, which is
positioned opposite to the surface 107a of the substrate 107. The opening direction D
of the sound hole 115 is perpendicular to the surface 107a of the substrate 107.
A housing 117 having the cavity S3 and the sound hole 115 is formed using
the substrate 107 and the cover member 109. Herein, the backside 107b of the
substrate 107 forms the backside of the housing 117, and the exterior surface of the top

21
portion 113 having the sound hole 115 forms a surface 117a of the housing 117.
As shown in FIGS. 6 and 7, the support 105 is constituted of a mount portion
121 for mounting the main body 103 of the microphone module 101, a pair of
extended portions 123, which are extended horizontally from the mount portion 121 in
a direction perpendicular to the opening direction D of the sound hole 115, and a
plurality of intermediate connection terminals 125, which are elongated from the
mount portion 121 to the extended portions 123.
The mount portion 121 is constituted of a mount area 127a having a
rectangular shape in plan view, on which the main body 103 of the microphone module
101 is mounted opposite to the backside 107b of the substrate 107, and a pair of side
walls 129 that vertically project from both ends of the mount area 127a. Hence, the
main body 103 of the microphone module 101 is precisely mounted on the mount area
127a defined between the side walls 129. The extended portions 123 are extended
outwardly from the upper ends of the side walls 129; hence, they are positioned
externally of the mount area 127a in plan view.
The intermediate connection terminals 125 are formed at the prescribed
positions in contact with the external connection terminals 111 under the condition in
which the main body 103 of the microphone module 101 is mounted on the mount area
127a of the mount portion 121. The main body 103 of the microphone module 101 is
fixed to the support 105 in such a way that the backside 107b of the housing 117 is
positioned opposite to the mount area 127a of the mount portion 121, thus electrically
connecting the external connection terminals 111 to the intermediate connection
terminals 125. Incidentally, the intermediate connection terminals 125 are each
horizontally extended along the mount area 127a, vertically elongated along the side
walls 129, and horizontally elongated along surfaces 123a of the extended portions

22
123, which are vertically elevated from the mount area 127a and which are
horizontally extended externally of and in parallel with the mount area 127a.
Heights of the surfaces 123a of the extended portions 123 measured from the
mount area 127a are determined such that they are lower than the height of the main
body 103 of the microphone module 101 mounted on the mount area 127a.
Next, a mounting structure for mounting the microphone module 101 on the
circuit board 7 as well as a portable electronic device 102 incorporating the
microphone module 101 will be described with reference to FIG. 8.
In FIG. 8, the microphone module 101 is mounted on the mount portion 9 of
the circuit board 7 installed in the portable electronic device 102 in such a way that the
opposite surface 45 of the circuit board 7 opposite to the mount portion 9 is directed
toward the sound port 5a of the housing 5. That is, when the housing 117 of the
microphone module 101 is inserted into the through-hole 47 from the mount portion 9
of the circuit board 7, the surfaces 123a of the extended portions 123 come in contact
with the mount portion 9 in the periphery of the through-hole 47. Since the
connection pads 49 are formed on the mount portion 9 in the periphery of the
through-hole 47, the intermediate connection terminals 125 formed on the surfaces
123 a of the extended portions 123 are brought into contact with the connection pads 49,
thus establishing an electrical connection between the circuit board 7 and the external
connection terminals of the main body 103 of the microphone module 101.
In the above, the microphone module 101 is mounted on the circuit board 7 in
such a way that the surface 117a of the housing 117 is directed to the mount portion 9;
hence, the sound hole 115 of the microphone module 101 is opened vertically relative
to the opposite surface 45 of the circuit board 7 so as to directly face the sound port 5a
of the housing 5 of the portable electronic device 102.

23
A ring-shaped anti-sound-leak gasket 131 is held between the sound hole 115
and the sound port 5a, which are positioned opposite to each other. Thus, it is
possible to prevent sound, which is introduced into the housing 5 via the sound port 5 a,
from being dispersed inside of the housing 5; that is, the ring-shaped anti-sound-leak
gasket 131 makes it possible to efficiently propagate sound into the cavity S3.
In FIG. 8, the surface 117a of the housing 117 of the microphone module 101
is lower than the opposite surface 45 of the circuit board 7; but this is not a restriction.
That is, the surface 117a of the housing 117 can be placed substantially in the same
plane with the opposite surface 45 of the circuit board 7; alternatively, it can be placed
higher than the opposite surface 45 of the circuit board 7.
FIG. 9 shows a portable electronic device 104 in which the microphone
module 101 is mounted on the circuit board 8 whose mount portion 10 is directed to
the sound port 6a of the housing 6, wherein the main body 103 of the microphone
module 101 is removed from the support 105, which is not necessarily used, and is
thus reliably mounted on the circuit board 8.
In the above, the through-hole 47 is not necessary so that the main body 103
of the microphone module 101 is simply mounted on the circuit board 8 under the
condition in which the backside 107b of the housing 117 is positioned opposite to the
mount portion 10 having the connection pads 49. Herein, the external connection
terminals 111 exposed on the backside 107b of the housing 117 are brought into
contact with the connection pads 49, thus establishing an electrical connection between
the microphone module 101 and the circuit board 8. Herein, the microphone module
101 is installed in the portable electronic device 104 in such a way that the sound hole
115 is opened above the mount portion 10 of the circuit board 8 so as to directly face
the sound port 6a of the housing 6.

24
In FIG. 8, similar to the microphone module 1, the microphone module 101,
which is installed in the portable electronic device 102 by way of the aforementioned
mounting structure, is arranged in such a way that the housing 117, which vertically
projects above the surfaces 123a of the extended portions 123, is inserted into and
engaged with the through-hole 47 of the circuit board 7, wherein it is possible to
reduce the projection height of the microphone module 101, which vertically projects
from the mount portion 9 of the circuit board 7.
Due to the insertion of the housing 117 into the through-hole 47 of the circuit
board 7, it is possible to reliably avoid the positional deviation of the microphone
module 101 relative to the circuit board 7; hence, it is possible to improve the
mounting strength (or packaging strength) of the microphone module 101 mounted on
the circuit board 7.
As shown in FIGS. 8 and 9, the main body 103 of the microphone module 101,
which is detached from the support 105, can be reliably and easily mounted on the
circuit board 7 and 8 respectively by appropriately changing the direction of the
housing 117. Thus, it is possible to improve the degree of freedom in mounting the
microphone module 101 on the circuit boards 7 and 8; and it is therefore possible to
further improve the degree of freedom in designing the portable electronic devices 102
and 104.
In the second embodiment, the main body 103 of the microphone module 101,
which is mounted on the mount area 127a of the mount portion 121, vertically projects
above the surfaces 123 a of the extended portions 123; but this is not a restriction. For
example, as shown in FIG. 10, a support 141 is designed to completely incorporate the
main body 103 of the microphone module 101 within a mount portion 143. Herein,
the surfaces 123 a of the extended portions 123 can be adjusted in height in such a way

25
that they are substantially placed in the same plane as the surface 117a of the housing
117 having the sound hole 115. Alternatively, the heights of the surfaces 123a of the
extended portions 123 are higher than the height of the main body 103 of the
microphone module 101.
FIG. 10 shows a potable electronic device 155 incorporating a microphone
module 145, which is mounted on a circuit board 147 in such a way that the surface
117a of the housing 117 is directed to a mount portion 149 of the circuit board 147.
In this case, it is necessary to form a through-hole 151, which allows a sound hole 115
to communicate with the exterior, in the circuit board 147. Due to the
aforementioned constitution of the microphone module 145 mounted on the circuit
board 147, even when an opposite surface 153 of the circuit board 147 is positioned
opposite to the sound port 6a of the housing 6, the sound hole 115 can directly face the
sound port 6a via the through-hole 151 of the circuit board 147. In the portable
electronic device 155, it is preferable that an anti-sound-leak gasket 157 be arranged
between the sound port 6a of the housing 6 and the through-hole 151 of the circuit
board 147, which are positioned opposite to each other.
As shown in FIG. 7, the mount portion 121 for mounting the microphone
module 101 is constituted of the bottom 127 having a rectangular shape in plan view
and the side walls 129 that vertically project from both ends of the bottoml27; but this
is not a restriction. That is, the mount portion 121 can be simply formed using the
bottom 127 only. In this modification, the extended portions 123 are directly and
horizontally extended from the periphery of the bottom 127. In short, this
modification indicates that the support 105 is formed substantially in a rectangular
shape, wherein when the main body 103 of the microphone module 101 is fixed onto
the mount portion 121, the housing 117 entirely projects from the surfaces 123a of the

26
extended portions 123.
In the aforementioned modification, the microphone module 101 can be
mounted on the circuit board while the housing 117 is inserted into the through-hole of
the circuit board; hence, it is possible to further reduce the projection height of the
microphone module 101 vertically projecting from the mount portion of the circuit
board.
In the mount portion 121, the intermediate connection terminals 125 are
elongated onto the surfaces 123a of the extended portions 123; alternatively, they can
be elongated onto the backsides of the extended portions 123, or they can be elongated
onto the backside of the bottom 127 opposite to the mount area 127a. In this
modification, the main body 103 of the microphone module 101 is unnecessarily
removed from the support 105, wherein the surface 117a of the housing 117 having the
sound hole 115 can be easily arranged on both of the mount portion 9 and opposite
surface 45 of the circuit board 7.
The external connection terminals 111 of the main body 103 of the
microphone module 101 are exposed on the backside 107b of the housing 117 along
the opening direction of the sound hole 115; but this is not a restriction. FIG. 11
shows a portable electronic device 173 incorporating a microphone module 171 whose
main body 103-is mounted on the mount portion 9 of the circuit board 7 by way of a
support 163, wherein they are exposed on the backside 107b of the housing 117 having
a sound hole 161 lying along an opening direction E. That is, the sound hole 161 is
formed at a prescribed position of a substrate 107 having the backside 107b, on which
the external connection terminals 111 are exposed.
When the main body 103 of the microphone module 171, in which the sound
hole 161 is opened on the backside 107b of the substrate 107, is mounted on a mount

27
area 165a of the support 163, the sound hole 161 is exposed to communicate the
exterior via an interconnection hole 167 running through a bottom 165 in its thickness
direction.
When the microphone module 171 is installed in the portable electronic
device 173, it is necessary to insert a gasket 175 between the interconnection hole 167
of the support 163 and the sound port 5a of the housing 5.
When the heights of the surfaces 123a of the extended portions 123, which are
positioned opposite to a mount portion 165a of the support 163, is lower than the
height of the main body 103 of the microphone module 171, it is necessary to form the
through-hole 47 for use in the insertion of the housing 117 in the circuit board 7 on
which the microphone module 171 is mounted.
In the microphone modules 1 and 101 according to the first and second
embodiments, when the surfaces 13 A and 123 a of the extended portions 43 and 123
are brought into contact with the mount portion 9 of the circuit board 7, it is necessary
to form the through-hole 47 running through the circuit board 7 in its thickness
direction; but this is not a restriction. That is, the first and second embodiments
require that at least a recess be formed in the mount portion 9 of the circuit board 7 so
as to enable the insertion of the housings 41 and 117. Herein, it is necessary that the
depth of the recess be greater than the projection heights of the housings 41 and 117,
which vertically project from the surfaces 13A and 123a of the extended portions 43
and 123. When the sound holes 25 and 115 are positioned opposite to the bottom of
the recess, it is necessary to additionally form a through-hole at the bottom of the
recess so as to expose the sound holes 25 and 115 to the exterior.
Lastly, the present invention is not necessarily limited to the aforementioned
embodiments, which can be further modified within the scope of the invention defined

28
by the appended claims.

29
WE CLAIM
1. A microphone module comprising:
a housing having a hollow cavity and a sound hole, via which the hollow
cavity communicates an exterior;
a microphone chip for detecting sound, which is arranged inside of the hollow
cavity;
a plurality of external connection terminals that are electrically connected to
the microphone chip; and
a plurality of extended portions that are horizontally extended from both ends
of the housing in a direction perpendicular to an opening direction of the sound hole,
wherein the plurality of external connection terminals are each elongated onto
a surface or a backside of the extended portions, and
wherein the housing partially projects from the surfaces of the extended
portions.
2. A microphone module according to claim 1, wherein the plurality of external
connection terminals are each elongated onto a backside of the housing, which is
positioned opposite to the surfaces of the extended portions.
3. A microphone module according to claim 1, wherein the housing is
constituted of a substrate for fixedly mounting the microphone chip on a surface
thereof and a cover member that covers the surface of the substrate so as to form the
hollow cavity, and wherein the extended portions are formed using the substrate and
are extended externally of the cover member.

30
4. A microphone module according to claim 1, wherein the plurality of extended
portions are formed using a plurality of leads, each having a conductivity, which serve
as the plurality of external connection terminals, and wherein the housing is formed
using a resin mold for sealing the plurality of leads.
5. A microphone module comprising:
a main body, which is constituted of a housing having a hollow cavity, a
microphone chip that is arranged inside of the hollow cavity so as to detect sound, and
a plurality of external connection terminals that are each electrically connected to the
microphone chip, wherein the housing has a sound hole for communicating the hollow
cavity to an exterior, and wherein the plurality of external connection terminals are
each elongated onto a backside of the housing in a direction perpendicular to an
opening direction of the sound hole; and
a support for mounting and supporting the main body, wherein the support is
constituted of a mount portion that is positioned opposite to the backside of the
housing so as to mount the main body, a plurality of extended portions that are
horizontally extended externally from the mount portion in a direction perpendicular to
the opening direction of the sound hole, and a plurality of intermediate connection
terminals that are elongated from the mount portion to the extended portions, and
wherein the intermediate connection terminals are elongated onto surfaces of the
extended portions lying in parallel with the mount portion.
6. A microphone module according to claim 5, wherein heights of the surfaces of
the extended portions measured from the mount portion are lower than a height of the

31
main body mounted on the mount portion.
7. A mounting structure for mounting a microphone module on a mount portion
of a circuit board, wherein the microphone module includes a housing having a hollow
cavity and a sound hole for communicating the hollow cavity with an exterior, a
microphone chip that is arranged inside of the hollow cavity so as to detect sound, a
plurality of extended portions that are horizontally extended from the housing in a
direction perpendicular to an opening direction of the sound hole, and a plurality of
connection terminals that are formed in the extended portions and are electrically
connected to the microphone chip, and wherein when the housing is inserted into a
hole running through the mount portion of the circuit board, the extended portions
come in contact with the mount portion so that the plurality of connection terminals
come in contact with a plurality of connection pads formed on the mount portion of the
circuit board, thus establishing an electrical connection between the microphone
module and the circuit board.
8. A portable electronic device in which a microphone module is mounted on a
mount portion of a circuit board incorporated in a housing, wherein the microphone
module includes a housing having a hollow cavity and a sound hole for
communicating the hollow cavity with an exterior, a microphone chip that is arranged
inside of the hollow cavity so as to detect sound, a plurality of extended portions that
are horizontally extended from the housing in a direction perpendicular to an opening
direction of the sound hole, and a plurality of connection terminals that are formed in
the extended portions and are electrically connected to the microphone chip, and
wherein when the housing is inserted into a hole running through the mount portion of

32
the circuit board, the extended portions come in contact with the mount portion so that
the plurality of connection terminals come in contact with a plurality of connection
pads formed on the mount portion of the circuit board, thus establishing an electrical
connection between the microphone module and the circuit board.

A microphone module is mounted on a mount portion of a circuit board
incorporated in a portable electronic device, wherein it includes a housing having a
hollow cavity and a sound hole for communicating the hollow cavity with the exterior,
a microphone chip for detecting sound in the hollow cavity, a plurality of external
connection terminals electrically connected to the microphone chip, and a plurality of
extended portions that are horizontally extended from the housing in a direction
perpendicular to the opening direction of the sound hole. The external connection
terminals are formed on the surfaces of the extended portions; and the housing
partially projects from the surfaces of the extended portions.