JP4197353B2 - Circuit board and electronic equipment - Google Patents

Description

  The present invention relates to a circuit board and an electronic device in which an electronic component is mounted on a base material.

In the circuit board 200 shown in FIG. 10, a cylindrical frame 203 is connected to the connection terminals 204 of the base 201 via solder so as to surround a plurality of electronic components 202 mounted on the base 201.
After the filler 205 filled inside the frame body 203 is solidified, the frame body 203 is covered with a cover body 207 such as a metal shield cover, and then the display body 208 (the holder 208A and the liquid crystal main body) is covered with the cover body 207. 208B) is fixed.

In the circuit board 200, the filling amount of the filler 205 is determined in advance so that the top surface 205A of the filler 205 is positioned along the same surface of the top portion 203A of the frame 203.
Accordingly, after the filler 205 is solidified, the top surface 205A of the filler 205 supports the display device 208 via the cover body 207.

JP-A-10-115835

In recent years, there has been a demand for further thinning of circuit boards.
For such a problem, a circuit board in which the height of the frame body is set so that the top of the electronic component is in contact with the cover body can be considered, but it is not preferable because the electronic component may be short-circuited.

  SUMMARY An advantage of some aspects of the invention is to provide a circuit board and an electronic device that can prevent a short circuit of an electronic component and can be thinned.

The circuit board according to the present invention includes a base material, an electronic component mounted on the base material, a filler in contact with the base material and the component, a first region in contact with the filler, and the filler. A lid having a second region where the electronic component is exposed and a third region where the electronic component is exposed, and the second region is between the first region and the third region. The lid includes a first surface, a second surface opposite to the first surface, and a through-hole penetrating the first surface and the second surface. The second region and the third region are formed by the through hole, and the top of the electronic component is located between the first surface and the second surface in the through hole.

  Here, as the lid, for example, by providing a through hole at a predetermined position of the flat plate, a region in contact with the filler on the back surface of the flat plate is set as a first region, and a region surrounded by the inner surface of the through hole is formed. A flat plate that is in contact with the filler by adopting a structure in which the second region is a region where the electronic component is exposed in the second region and the flat region is smaller than the flat area of the filler. A structure in which the entire rear surface of the first region is a first region, a region where the flat plate does not reach the plane of the filler is a second region, and a region where the electronic component is exposed in the second region is a third region Etc. can be illustrated.

In addition, the flat plate having a plane area smaller than the plane area of the filler does not need to have a shape similar to the plane shape of the solidified filler. For example, when the plane shape of the solidified filler is a rectangular shape, A U-shaped, substantially L-shaped plane, substantially T-shaped plane, etc., a substantially cross-shaped plane, a substantially H-shaped plane, or a lattice-shaped lid may be employed.
And when a through-hole is employ | adopted as a 2nd area | region, in order that a filler and an electronic component may be exposed, a through-hole which is similar to the planar shape of an electronic component and larger than the planar outline dimension of an electronic component is used. It only has to be formed.
Further, the term “exposed” as used herein refers to a state of being exposed through the through hole, and it does not matter whether a part of the electronic component is located inside the through hole.

In the present invention, since the lid having the second region where the filler is exposed and the third region where the electronic component is exposed, the top of the electronic component is the same as the back surface of the lid. Even if the electronic parts are arranged along the plane, the electronic parts do not come into contact with the lid, so that the electronic parts are not short-circuited.
Moreover, in this invention, since the top part of an electronic component can be arrange | positioned to the position along the same plane with respect to the upper surface of a lid | cover, it can reduce in thickness compared with the past.

  Generally, a display device such as an LCD is disposed on the surface of an electronic device and may be strongly pressed by a user of the electronic device. Further, a display device such as an LCD including a glass plate or the like as a component may be broken by being strongly pressed and bent. Therefore, it is important to generate the stress for pressing evenly across the display surface that can be pressed so that a display device such as an LCD does not bend even if it is strongly pressed.

  In the present invention, when the display device is arranged over the top of the electronic component and the top surface of the lid, and the display device is in contact with the top and the lid of the electronic component, the lid is a base material via a filler. Therefore, it is possible to generate a large stress against a strong pressing. In addition, since the electronic component is mounted on the base material and is in contact with the base material via the filler, a large stress can be generated against a strong pressing on the top. Furthermore, the filler that contacts the lid is the same as the filler that contacts the electronic component, and since the filler links the stress generated by the lid with the stress generated by the electronic component, the two stresses are more evenly distributed. can do.

Further, in the present invention, since the second region and the third region are formed by the through-hole provided in the lid, it can be arbitrarily selected according to the planar shape, planar dimension, arrangement location, and number of the electronic component. The second region and the third region can be formed.
Furthermore, in the present invention, since the top of the electronic component is between the first surface and the second surface in the through hole, the top B of the electronic component is flush with the first surface of the lid. If it arrange | positions in the position along, a circuit board can be reduced in thickness.

Further, the circuit board according to the present invention comprises a substrate, an electronic component mounted on the substrate, a filler in contact with said and said substrate components, and a lid covering the filler, the The lid has a first surface, a second surface opposite to the first surface, and a through-hole penetrating the first surface and the second surface, and the filling The agent covers the top of the electronic component, and the filler covering the top of the electronic component is located between the first surface and the second surface in the through hole.

In the present invention, since the electronic component is covered with the filler, the electronic component is not in direct contact with the lid, thereby preventing a short circuit of the electronic component.
Then, in the present invention, the filler covering the top of the electronic component, as compared to more conventional to be located between the first surface and the second surface of the through hole thin It will be possible.

And the circuit board mentioned above is used for the electronic device of this invention.
Furthermore, the electronic device of the present invention further includes a display device, the filler is in contact with the first surface of the lid, and the display device is provided on the second surface of the lid.
In the present invention as described above, the display device is provided on the second surface of the lid, and the lid is in contact with the base material via the filler. Can be made.

According to the circuit board and the electronic device of the present invention, the filler is exposed in the second region of the lid, and the electronic component is exposed in the third region. As a result, the thickness can be reduced.
Further, according to the circuit board and the electronic device of the present invention, the filler covering the top of the electronic component protrudes in the fourth region of the lid, so that the electronic component is not short-circuited and is thinner than the conventional one. It has the effect of being able to.

(First embodiment)
DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments according to the present invention will be described in detail based on the drawings.
As shown in FIG. 1, the electronic device 10 according to the first embodiment includes a circuit board 12 accommodated in a housing 11.
The circuit board 12 according to the first embodiment includes a base material 13, a plurality of electronic components 14 and 14A mounted on the base material 13, and a frame 15 joined to the base material 13 so as to surround the electronic components 14 and 14A. A filler 16 in contact with the base material 13, the plurality of electronic components 14, and the frame body 15, a lid 18 covered on the frame body 15, and a display unit 19 such as an LCD or EL fixed to the lid 18. Have.

  The frame 15 includes a peripheral wall 15A formed in a substantially rectangular cylindrical shape, a first flange 15B protruding outward from the base of the peripheral wall 15A, and an inward extension at the top of the peripheral wall 15A. The second flange 15C is extended, and the cross-sectional shape is formed in a substantially crank shape by the peripheral wall 15A, the first flange 15B, and the second flange 15C.

As for such a frame 15, the 1st flange 15B is being fixed to the connection terminal 19 (refer FIG. 1) of the base material 13 via solder | pewter.
By providing the second flange 15 </ b> C at the top of the peripheral wall 15 </ b> A, the opening 21 is formed at the top of the frame 15.

A filler 16 is filled in the frame 15 surrounding the plurality of electronic components 14 and 14A. The filler 16 is in contact with the base material 13, the plurality of electronic components 14, 14 </ b> A, and the frame body 15.
The filling amount of the filler 16 is determined in advance so that the top surface 16A is substantially flush with the second flange 15C when the frame body 15 is filled.

The lid 18 is a shield cover including an outer wall portion 18A that is slightly larger than the peripheral wall 15A of the frame body 15 and a lid body 18B formed at the top of the outer wall portion 18A.
The lid 18 includes a first region 23 in contact with the top surface 16A of the filler 16, a second region 27 where the top surface 16A of the filler 16 is exposed, and a third region where the top portion 14B of the electronic component 14A is exposed. 26.
The lid 18 includes a first surface 22A in contact with the top surface 16A of the filler 16 in the first region 23, a second surface 22B opposite to the first surface 22A, and a first surface 22A. And a through hole 24 penetrating the second surface 22B.
A region surrounded by the inner surface of the through hole 24 and only the top surface 16 </ b> A of the filler 16 is exposed becomes the second region 26.

Returning to FIG. 1, the first electronic component 14 </ b> A is the electronic component having the largest height dimension among the plurality of electronic components 14.
The other electronic components 14 excluding the first electronic component 14A have a height dimension smaller than that of the second flange 15C of the frame body 15.

  Therefore, as shown in FIG. 3, the first electronic component 14 </ b> A has a top portion 14 </ b> B that protrudes upward from the top surface 16 </ b> A of the filler 16, and the first surface 22 </ b> A and the second surface 22 </ b> B in the through hole 24. Between. The other electronic components 14 are buried in the filler 16.

Thus, by using the through hole 24 as the second region 27, the filler 16 and the first electronic component 14 </ b> A are exposed in the through hole 24.
A region where the top portion 14 </ b> B of the first electronic component 14 </ b> A is exposed becomes the third region 26 inside the second region 27.

Specifically, the top portion 14B of the first electronic component 14A is disposed at a position along the same plane with respect to the upper surface 18D of the lid 18.
The through hole 24 has a shape similar to the planar shape of the first electronic component 14A and is larger than the planar contour dimension of the first electronic component 14A.

  In the first embodiment, as shown in FIG. 1, the top portion 14 </ b> B of the first electronic component 14 </ b> A is positioned inside the through hole 24 as one form in which the filler 16 and the top portion 14 </ b> B of the first electronic component 14 </ b> A are exposed. However, the form of exposure is not limited to this.

  That is, the exposure of the filler 16 and the top portion 14B of the first electronic component 14A refers to a state in which the top portion 14B of the first electronic component 14A and the filler 16 are exposed through the through hole 24. It does not matter whether the top portion 14B is located inside the through hole 24.

  A display device 20 is held on the upper surface of the lid 18. The display device 20 includes a holder 20A and a liquid crystal main body 20B.

According to the electronic device 10 and the circuit board 12 of the first embodiment, the lid 18 includes the second region 26 where the filler 16 is exposed and the third region 26 where the first electronic component 14A is exposed. ing.
Thereby, even if the top portion 14B of the first electronic component 14A is arranged along the same plane with respect to the back surface 18C of the lid body 18B, the first electronic component 14A is placed on the lid 18 (specifically, the lid body 18B). Since it does not contact, the 1st electronic component 14A does not short-circuit.

  Furthermore, according to the electronic device 10 and the circuit board 12 of the first embodiment, as shown in FIG. 1, the top portion 14B of the first electronic component 14A is disposed up to a position along the same plane with respect to the upper surface 18D of the lid 18. Therefore, the thickness can be reduced as compared with the conventional case.

  Furthermore, according to the electronic device 10 and the circuit board 12 of the first embodiment, since the second region 27 and the third region 26 are formed by the through hole 24 provided in the lid body 18B, the first electronic The second region 27 and the third region 26 can be arbitrarily formed according to the planar shape, planar dimension, arrangement location, and number of the component 14A.

  In addition, according to the electronic device 10 and the circuit board 12 of the first embodiment, the display device 20 is arranged over the top portion 14B of the electronic component 14A and the top surface of the lid portion 18, and the display device 20 is the top portion 14B of the electronic component 14A. Since the lid portion 18 is in contact with the base material 13 via the filler 16, a large stress can be generated against strong pressing.

  Furthermore, according to the electronic device 10 and the circuit board 12 of the first embodiment, since the electronic component 14A is mounted on the base material 13 and is in contact with the base material 13 via the filler 16, the top portion 14B. It is possible to generate a large stress against a strong pressing against the.

  And according to the electronic device 10 and the circuit board 12 of 1st Embodiment, the filler 16 which the cover part 18 contact | connects is the same as the filler 16 which the electronic component 14A contacts, and stress with which the cover part 18 is generate | occur | produced. Since the filler 16 cooperates with the stress generated by the electronic component 14A, the two stresses can be made more uniform.

(Second Embodiment)
Next, 2nd Embodiment-3rd Embodiment are described based on FIGS. 4-7. In addition, in 2nd Embodiment-3rd Embodiment, the same code | symbol is attached | subjected about the same similar member as the circuit board 12 of 1st Embodiment, and description is abbreviate | omitted.

  As shown in FIGS. 4 and 5, the electronic device 30 and the circuit board 32 of the second embodiment are obtained by removing the frame body 15 (see FIG. 1) from the electronic device 10 and the circuit board 12 of the first embodiment. Other configurations are the same as those of the first embodiment.

The example which fills the circuit board 32 of 2nd Embodiment with the filler 16 is demonstrated based on FIG. 6 (A)-(C).
As shown in FIG. 6A, after mounting a plurality of electronic components 14 on the base material 11, a frame portion 35 is disposed at a predetermined position of the base material 13 so as to surround these electronic components 14.
Next, the nozzle 37 is inserted into the opening 36 of the frame portion 35, and the liquid or viscous filler 16 is filled into the frame portion 35 from the nozzle 37.

The filler 16 is filled up to the top of the frame portion 35 by completing the filling of the filler 16 having a predetermined filling amount.
When the filling of the filler 16 is completed, the top portion 14B of the first electronic component 14A protrudes from the top surface 16A of the filler 16 as shown in FIG.
After the filler 16 is solidified, the frame portion 35 is removed from the base material 13. After the frame portion 35 is removed, the solidified filler 16 is covered with the lid 18 as shown in FIG.

According to the electronic device 30 and the circuit board 32 of the second embodiment, the same effects as those of the electronic device 10 and the circuit board 12 of the first embodiment can be obtained.
And according to the electronic device 30 and the circuit board 32 of 2nd Embodiment, since the frame 15 of 1st Embodiment is not provided, the area which mounts the frame 15 on the base material 13 becomes unnecessary, and mounting area The substrate 13 can be downsized. Further, since the frame body is eliminated, the height of the circuit board 32 can be determined by the height of the electronic component 14 regardless of the frame body. Further, it is not necessary to provide each circuit board 32 with a high-accuracy frame that prevents the filler 16 from leaking between the base material 13 and the cost of components can be reduced.

  Further, according to the electronic device 30 and the circuit board 32 of the second embodiment, the filler 16 in contact with the lid 18 is the same as the filler 16 in contact with the electronic component 14A, and the stress generated by the lid 18 is the same. Since the filler 16 cooperates with the stress generated by the electronic component 14A, the two stresses can be made more uniform.

(Third embodiment)
As shown in FIG. 7, in the electronic device 40 and the circuit board 42 of the third embodiment, the first region 23 where the first surface 22A is in contact with the filler 16 and the filler 16 are exposed, and the first electronic component is exposed. The top portion 14B of 14A and the top surface 16B of the filler 16 covering the top portion 14B are located between the same surface as the first surface 22A and the second surface 22B opposite to the first surface 22A. The fourth region 26 is provided with a lid 18 having the same structure as that of the first embodiment.

  Here, the top portion 14B of the first electronic component 14A in the fourth region 26 and the top surface 16B of the filler 16 are higher than the top surface 16A in contact with the first surface 22A of the lid 18 in the first region 23. It only needs to protrude upward on the second surface 22B side of the lid 18, and the amount of protrusion of the top portion 14B of the first electronic component 14A and the top surface 16B of the filler 16 is arbitrary.

  According to the electronic device 40 and the circuit board 42 of the third embodiment, since the top portion 14B of the first electronic component 14A is covered with the filler 16, the first electronic component 14A does not directly contact the lid 18, and this Therefore, the first electronic component 14 is not short-circuited.

  Further, according to the electronic device 40 and the circuit board 42 of the third embodiment, the filler 16 is exposed in the fourth region 26, and the top 14B of the first electronic component 14A and the filler 16 that covers the top 14B are formed. Since the top surface 16B is located between the same surface as the first surface 22A and the same surface as the second surface 22B, the top surface 16B can be reduced in thickness as compared with the prior art.

Here, the top portion 14B and the filler 16 of the first electronic component 14A shown in the first embodiment and the second embodiment are located between the same surface as the first surface 22A and the same surface as the second surface 22B. The contents to be described will be described in detail with reference to FIGS.
The through hole 24 formed as the second region 27 and the third region 26 has a shape similar to the planar shape of the first electronic component 14A and is formed larger than the planar contour size of the first electronic component 14A. .
Therefore, the filler 16 is exposed in the second region 27, and the first electronic component 14 </ b> A is exposed in the third region 26.

Here, “exposed” refers to a state in which the filler 16 is exposed in the second region 27 and the first electronic component 14 </ b> A is exposed in the third region 26.
That is, as the form of “exposure”, as shown in FIG. 8A, the top portion 14B of the first electronic component 14A is the same surface as the first surface 22A, in other words, the same as the top surface 16A of the filler 16. The form located along the plane and the form in which the top portion 14B of the first electronic component 14A protrudes from the top surface 16A of the filler 16 as shown in FIG. 8B are included.
The top portion 14B of the first electronic component 14A is disposed in the range of the height dimension H of the through hole 24.

(Modifications 1 to 3)
In the first to third embodiments, the through hole 24 is exemplified as the second region 27 and the third region 26. However, the second region and the third region can be obtained by other means. is there.
For example, by setting the shape of the lid to a flat plate having a flat area smaller than the flat area of the filler 16, the entire back surface of the flat plate in contact with the filler 16 is set as the first region, and the flat surface of the filler 16 is used. It is also possible to make the second region and the third region the regions that the flat plate does not reach.

Specifically, the second region 51 and the third region are obtained by adopting a substantially U-shaped lid 50 as in Modification 1 shown in FIG. 9A. The lid 50 is in contact with the top surface 16A of the filler 16 (first region).
The second region 51 is a region where the top surface 16A of the filler 16 is exposed, and the third region 52 is a region where the top portion 14B of the electronic component 14 is exposed.

As shown in FIG. 9A, the electronic component 14 has three top portions 14 </ b> B that protrude upward from the top surface 16 </ b> A of the filler 16 and are disposed below the surface 55 </ b> A of the lid 55. Yes.
On the other hand, in the remaining one electronic component 14, the top portion 14 </ b> B is arranged flush with the top surface 16 </ b> A of the filler 16.

Further, as in the second modification shown in FIG. 9B, the second region 56 and the third region 57 are obtained by adopting the substantially planar L-shaped lid 55. The lid 55 is in contact with the top surface 16A of the filler 16 (first region).
The second region 56 is a region where the top surface 16A of the filler 16 is exposed, and the third region 57 is a region where the top portion 14B of the electronic component 14 is exposed.

As shown in FIG. 9B, the electronic component 14 has three top portions 14 </ b> B that protrude above the top surface 16 </ b> A of the filler 16 and are disposed below the surface 55 </ b> A of the lid 55. Yes.
On the other hand, in the remaining one electronic component 14, the top portion 14 </ b> B is arranged flush with the top surface 16 </ b> A of the filler 16.

Furthermore, as in Modification 3 shown in FIG. 9C, the second region 61 and the third region 62 are adopted by adopting a lid 60 that covers substantially the right half of the top surface 16 </ b> A of the filler 16. Is obtained. The lid 60 is in contact with the top surface 16A of the filler 16 (first region).
The second region 61 is a region where the top surface 16A of the filler 16 is exposed, and the third region 62 is a region where the top portion 14B of the electronic component 14 is exposed.

As shown in FIG. 9C, the electronic component 14 has six top portions 14 </ b> B that protrude upward from the top surface 16 </ b> A of the filler 16 and are disposed below the surface 60 </ b> A of the lid 60. Yes.
On the other hand, in the remaining three electronic components 14, the top portion 14 </ b> B is arranged flush with the top surface 16 </ b> A of the filler 16.

  In addition, as other lid shapes, for example, those having a substantially plane T shape, such as a substantially cross shape in plane, a substantially H shape in plane, and a lattice shape are conceivable.

  In 1st Embodiment-3rd Embodiment, although the top surface 16A of the filler 16 showed the example which contact | connects the back surface 18C (1st surface 22A) of the lid | cover 18 which is the 1st area | region 23, When the filler 16 is solidified, there is a possibility that a slight gap is generated between the first region 23 and the top surface 16 </ b> A of the filler 16 due to the contraction called “shrink”.

However, such a gap is very small, and even if a gap is generated, the lid 18 bends and contacts the top surface 16A of the filler 16, so that the top surface 16A of the filler 16 is in the first region. 23 is substantially equivalent to the state of being in contact with 23.

  The present invention is suitable for application to a circuit board and an electronic device in which a filler is in contact with an electronic component mounted on a base material.

It is sectional drawing which shows the electronic device and circuit board of 1st Embodiment which concern on this invention. It is a perspective view which shows the circuit board of 1st Embodiment. It is a disassembled perspective view which shows the circuit board of 1st Embodiment. It is sectional drawing which shows the electronic device and circuit board of 2nd Embodiment which concern on this invention. It is a perspective view which shows the circuit board of 2nd Embodiment. It is sectional drawing explaining the example which fills the circuit board of 2nd Embodiment with a filler. It is sectional drawing which shows the electronic device and circuit board of 3rd Embodiment which concern on this invention. It is sectional drawing explaining the form which an electronic component exposes to the 2nd area | region which concerns on this invention. It is a perspective view which shows the modification of the lid | cover which concerns on this invention. It is sectional drawing which shows the conventional circuit board.

Explanation of symbols

10, 30, 40 Electronic device 12, 32, 42 Circuit board 13 Base material 14 Electronic component 14A First electronic component (electronic component)
14B Top portion 16 Filler 16A, 16B Top surface 18, 50, 55, 60 Lid 23 First region 24 Through hole 26, 52, 57, 62 Third region 27, 51, 56, 61 Second region

Claims (4)

A substrate;
An electronic component mounted on the substrate;
A filler in contact with the substrate and the component;
A lid comprising a first region in contact with the filler, a second region where the filler is exposed, and a third region where the electronic component is exposed ;
The second region is located between the first region and the third region;
The lid includes a first surface, a second surface opposite to the first surface, and a through-hole penetrating the first surface and the second surface;
The second region and the third region are formed by the through hole,
A circuit board in which a top portion of the electronic component is located between the first surface and the second surface in the through hole. A substrate;
An electronic component mounted on the substrate;
A filler in contact with the substrate and the component;
A lid covering the filler,
The lid has a first surface, a second surface opposite to the first surface, and a through-hole penetrating the first surface and the second surface;
The filler covers the top of the electronic component;
The circuit board in which the filler covering the top of the electronic component is located between the first surface and the second surface in the through hole.   An electronic device in which the circuit board according to claim 1 or 2 is used. The electronic device according to claim 3,
  A display device;
  The filler contacts the first surface of the lid;
  An electronic apparatus in which the display device is provided on the second surface of the lid.

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