KR102401456B1 - High density mounting module - Google Patents

Abstract

While an electronic component has sufficient mechanical strength and is fixed to a printed circuit board, the position shift at the time of solder reflow is suppressed, and a mounting position precision is improved.
A high-density mounting module comprising: a printed circuit board having a plurality of lands; and an electronic component mounted on the printed board and including a plurality of connection terminals connected to the plurality of lands, wherein the plurality of lands are disposed on each other in a first direction a plurality of connections of the electronic component, comprising first cutouts and second cutouts extending in opposite orientations, and third cutouts and fourth cutouts extending in orientations opposite to each other in a second direction orthogonal to the first direction; A solder fillet is formed extending from each side of the terminal over the surface of each land to which the connecting terminal is connected.

Description

High-density mounting module {HIGH DENSITY MOUNTING MODULE}

The present invention relates to a high-density mounting module, and more particularly, to a module for surface-mounting electronic components at high density on a printed circuit board.

BACKGROUND ART With progress in miniaturization and weight reduction of electronic device modules, miniaturization of individual electronic components such as semiconductor elements and electronic components to be mounted is promoted. In this type of module, in order to realize high-density mounting suitable for miniaturization of mounted components, a technique for surface-mounting electronic components on a printed circuit board is employed.

As described above, in the module employing the high-density surface mount technology, individual electronic components are mounted on a printed circuit board by solder reflow technology, and the mechanical strength of fixing the electronic components to the printed board is ensured; Reducing the electrical resistance between each connection terminal and the conductive layer of a printed circuit board is compatible.

Japanese Patent Laid-Open No. 10-335795

In the solder reflow technique, an appropriate amount of cream solder is attached to the mounting land of the printed circuit board by a printing method, the electronic components are aligned and mounted on the mounting land, and then heated to melt the solder, and then cooled By doing so, solder is solidified, and electrical connection is obtained, fixing an electronic component on a printed circuit board.

In this surface mount technology, when the solder is melted, since the electronic component is in a suspended state on the molten solder, the electronic component moves on the solder until it cools and solidifies, and the original component is aligned and mounted. may deviate from the position of As a technique for suppressing such positional shift, the technique described in Cited Document 1, for example, is proposed.

On the other hand, in order to secure the mechanical strength for fixing the electronic component to the printed circuit board, it is necessary to sufficiently form a solder fillet surrounding the connection terminal of the electronic component on the mounting land. To this end, it is necessary to supply a sufficient volume of solder to surround the connection terminals of the electronic component on the mounting land, which results in a situation in which the electronic component is more likely to move when the solder is melted.

The present invention has been made in view of such a situation, and its object is that the solder fillets surrounding the connection terminals of the electronic components are sufficiently formed on the mounting land so that the electronic components and the printed circuit board have sufficient mechanical strength. It is intended to provide a high-density mounting module having good mounting position accuracy by suppressing the movement of electronic components on the solder and shifting from the original position where they are aligned and mounted at the time of solder reflow.

The high-density mounting module of the first aspect of the present invention is a high-density mounting module comprising a printed circuit board having a plurality of lands, and an electronic component mounted on the printed board and including a plurality of connection terminals connected to the plurality of lands, The plurality of lands have first and second cutouts extending in orientations opposite to each other in a first direction, and third cutouts and fourth cutouts extending in orientations opposed to each other in a second direction orthogonal to the first direction. A solder fillet including a cutout extending from each side surface of the plurality of connection terminals of the electronic component to the surface of each land to which the connection terminals are connected is formed.

According to a second aspect of the present invention, in the first aspect, the plurality of lands have lands in which no cutouts are disposed.

According to a third aspect of the present invention, in the first aspect, the plurality of lands has a land having only one cutout disposed thereon.

According to a fourth aspect of the present invention, in the first aspect, the plurality of lands has at least four lands, and has four lands in which only one notch is disposed.

According to a fifth aspect of the present invention, in any one of the first to fourth aspects, each of the first cutout and the second cutout is disposed on a separate land, and the separate land comprises a second are spaced apart from each other in the direction

According to a sixth aspect of the present invention, in the fifth aspect, each of the third cutout and the fourth cutout is disposed on a separate land, and the separate land is spaced apart from each other in the first direction.

According to a seventh aspect of the present invention, in the sixth aspect, the plurality of lands further include a fifth cutout extending in the first direction and a sixth cutout extending in the second direction.

A high-density mounting module according to an eighth aspect of the present invention includes a printed circuit board having a plurality of lands and a solder resist covering respective perimeters of the plurality of lands and having a plurality of openings included in respective regions of the plurality of lands; A high-density mounting module mounted on a printed circuit board and including an electronic component including a plurality of connection terminals connected to a plurality of lands, wherein a plurality of openings included in the plurality of lands are opposite to each other in a first direction, and each A plurality of connection of electronic components, comprising: first and second protrusions protruding inward; A solder fillet is formed extending from each side of the terminal over the surface of each land to which the connecting terminal is connected.

According to the present invention, the solder fillet surrounding the connection terminal of the electronic component is sufficiently formed on the mounting land, so that the electronic component is fixed to the printed board with sufficient mechanical strength, and the position at which the electronic component is fixed is made of solder It is possible to provide a high-density mounting module having good mounting position accuracy by moving over the molten solder during reflow to suppress deviation from the original position mounted by alignment.

1 is a plan view of a first embodiment of a high-density mounting module of the present invention.
Fig. 2 is a plan view of a modified example of the first embodiment of the high-density mounting module of the present invention.
3 is a plan view of a further modified example of the first embodiment of the high-density mounting module of the present invention.
Fig. 4 is a cross-sectional view taken along line A-A' in Fig. 3 .
Fig. 5 is a cross-sectional view taken along the line segment B-B' in Fig. 3 .
FIG. 6 is a cross-sectional view taken along line C-C' in FIG. 3 .
7 is a plan view of another modified example of the first embodiment of the high-density mounting module of the present invention.
8 is a plan view of a second embodiment of the high-density mounting module of the present invention.

EMBODIMENT OF THE INVENTION Hereinafter, based on drawing, various embodiment of this invention is described.

<First embodiment>

Fig. 1 shows a module 101 as a first embodiment of the high-density mounting module of the present invention. The module 101 includes a printed circuit board 105 having a first land 111 , a second land 112 and a third land 113 . In the printed circuit board 105 , a first connection terminal 151 , a second connection terminal 152 connected to the corresponding respective of the first land 111 , the second land 112 , and the third land 113 , respectively. and an electronic component 150 including a third connection terminal 153 is mounted thereon.

A first cutout 121 extending in a first direction (X direction) is disposed on the first land 111 , and a second direction orthogonal to the first direction (X direction) is disposed on the second land 112 . A third notch 123 extending in the (Y direction) is disposed. Further, in the third land 113, there is a second cutout 122 extending in an orientation opposite to the first cutout 121 in the first direction (X direction), and a third cutout in the second direction (Y direction). A fourth cutout 124 extending in an orientation opposite to 123 is disposed.

In this first embodiment, during solder reflow, when a force to move the electronic component suspended in the molten solder in the negative direction of the first direction (X direction) is generated, the first notch 121 is formed in the second part of the electronic component. 1 The movement of the connection terminal 151 is suppressed. And when the force to move in a positive direction arises, the 2nd notch 122 suppresses the movement of the 3rd connection terminal 153 of an electronic component.

Similarly, when a force to move in the negative direction of the second direction (Y direction) is generated, the third notch 123 suppresses the movement of the connection terminal 151 of the electronic component, and when a force to move in the positive direction is generated , the second cutout 122 suppresses movement of the third connection terminal 153 of the electronic component.

In this way, in order to suppress the parallel movement of the electronic component floating in the molten solder in the first direction (X direction) and the parallel movement in the second direction (Y direction), at least at any position among the plurality of lands. In the first direction (X-direction), two cuts are drawn in opposite orientations, and in the second direction (Y-direction) orthogonal to the first direction (X-direction), the two cuts are drawn in opposite orientations. It is necessary to place two cutouts.

However, the movement of the electronic component suspended in the molten solder is not limited to parallel movement. For example, when a force is generated to move in the negative direction of the first direction (X direction), the first cutout 121 is Although it suppresses movement of the first connection terminal 151 of the electronic component in the negative direction of the first direction (X direction), the movement of the entire electronic component toward rotation with the first cutout 121 as the center is suppressed can't

Similarly, with respect to the second cutout 122 , the third cutout 123 , and the fourth cutout 124 , similarly to the first cutout 121 , each cutout is parallel to the connecting terminal of the electronic component in the corresponding direction. The movement can be suppressed, but the movement of the entire electronic component around each cutout cannot be suppressed.

With respect to the movement to be rotated, it is possible to suppress the positional shift by combining a plurality of cutouts. For example, the movement of the third connection terminal 153 is suppressed by the second cut-out 122 and the fourth cut-out 124 with respect to the movement to rotate clockwise around the first cutout 121 . to be prevented With respect to the movement to rotate in the counterclockwise direction, the respective movements of the first connection terminal 151 and the third connection terminal 153 are suppressed and prevented by the third cutout 123 and the fourth cutout 124 . do.

In the movement centered on the second cutout 122, clockwise rotation is the movement of the first connection terminal 151 by the first cutout 121, and counterclockwise rotation is the third cutout ( 123 ) and the fourth cutout 124 , each movement of the first connection terminal 151 and the third connection terminal 153 is suppressed.

In FIG. 1 , in the first land 111 in which the first cutouts 121 extending in the first direction (X direction) are disposed, the second cutouts 122 in the orientation opposite to the first cutouts 121 are disposed. The third land 113 and the first notch 121 and the second notch 122 are spaced apart from each other in a second direction (Y direction) orthogonal to the extending first direction (X direction).

In addition, the second land 112 on which the third cutout 123 extending in the second direction (Y direction) is disposed is the third cutout 124 disposed opposite to the third cutout 123 . The three land 113 and the third notch 123 and the fourth notch 124 are spaced apart from each other in a first direction (Y direction) orthogonal to the extending second direction (X direction).

Considering not only the direction in which the electronic component moves in parallel, but also suppression of positional shift in the rotational direction, it is more preferable that at least two cutouts extending in mutually opposing orientations are dispersed in lands spaced apart from each other.

Fig. 2 shows a modified example of the module 101 of the first embodiment of the present invention. In this modification, in the module 101 illustrated in FIG. 1 , the third cutout 123 disposed on the second land 112 is disposed on the first land 111 . The direction and orientation in which the third notches 123 are stretched are the same as the directions and orientations in which the third notches 123 described in FIG. 1 are stretched. In this modification, no cutouts are arranged on the second land 112 .

Also in this modified example, the first land 111 on which the third cutout 123 extending in the second direction (X direction) is disposed is a fourth cutout 124 oriented opposite to the third cutout 123 . The arranged third land 113 is spaced apart from each other in the first direction (Y direction) orthogonal to the second direction (X direction) in which the third and fourth cutouts 123 and 124 extend.

Fig. 3 shows another modified example of the module 101 of the first embodiment of the present invention. In this another modification, in addition to the module 101 described in FIG. 1 , the fifth cutout 125 and the third land 113 extending in the first direction (X direction) of the second land 112 are A sixth notch 126 extending in the first direction (X direction) and a seventh notch 127 extending in the second direction (Y direction) of the first land 111 are added.

The fifth cutout 125 and the sixth cutout 126 extend in an orientation opposite to each other in the first direction (X direction), and the seventh cutout 127 extends in the fourth cutout 124 and the second direction ( Y direction) in opposite orientations.

In this still another modified example, the negative direction of the first direction (X direction) suppresses movement of the first connection terminal 151 by the first cutout 121 , and suppresses the movement of the first connection terminal 151 by the sixth cutout 126 . Movement of the third connection terminal 153 is also suppressed. And with respect to the positive direction of the 1st direction (X direction), the 2nd notch 122 and the 5th notch 125 suppress each movement of the 3rd connection terminal 153 and the 2nd connection terminal 152. do.

With respect to the negative direction of the second direction (Y direction), the third notch 123 and the seventh notch 127 suppress the respective movement of the second connection terminal 152 and the first connection terminal 151 . About the positive direction of the 2nd direction (Y direction), the movement of the electronic component is suppressed by the 4th cutout 124, Here, it is the same as the module 101 described in FIG.

Moreover, in this still another modified example, it is a structure which suppresses the movement which the whole electronic component is going to move in the inclined direction similarly. For example, the movement in the oblique direction (positive/positive direction) in which the first direction (X direction) is positive and the second direction (Y direction) is also positive, the second cutout 122 and the fourth cutout 124 are positive. 3 It is prevented by suppressing the movement of the connection terminal 153 .

Similarly, as for the movement in the positive/negative direction, the third cutout 123 and the fifth cutout 125 suppress the movement of the second connection terminal 152 , and the movement in the negative/positive direction is the fourth cutout 124 . and the sixth cut-out 126 suppresses the movement of the third connection terminal 153 , and the movement in the negative/negative direction is the first cut-out 121 and the seventh cut-out 127 of the first connection terminal 151 . By suppressing the movement, it is possible to prevent the movement of the electronic component.

In this way, if parallel movement in the first direction (X direction) and the second direction (Y direction) can be suppressed and positional shifts in the four oblique directions can be suppressed, the electronic component can be formed centering on an arbitrary point All rotational movements can also be suppressed. In this still another modified example, there is an effect of suppressing the positional shift equally in all directions.

4, 5, and 6 are a cross-sectional view of a line segment A-A' and a line segment B-B' of the third land 113 described in FIG. 3, and a line segment C-C' of the second land 112, respectively. It is a cross-sectional view of a part. 4 and 5 , the third land 113 is disposed on the printed circuit board 105 , and the third connection terminal 153 of the electronic component 150 is soldered on the third land 113 .

Here, since the line segment A-A' is a portion where the second cutout 122 and the sixth cutout 126 are disposed, the third land 113 protrudes laterally from the end of the third connection terminal 153 . quantity is small In addition, since it is limited on the third land 113 which is a conductive layer that can hold the solder at the time of melting, the molten solder in the transverse direction of the end of the third connection terminal 153 returns. The amount is very small, no solder fillet is formed, and a thin solder layer 160 is formed on the surface of the third land 113 .

On the other hand, the phenomenon in which the electronic component 150 causes positional displacement in the solder reflow process is caused by floating and moving on the molten solder. Therefore, unless the molten solder is turned around in the transverse direction of the end of the third connecting terminal 153, the third connecting terminal 153 cannot move in the transverse direction, that is, in the A direction and A' direction in FIG. . Therefore, in the portion where the cutout is arranged, the movement of the electronic component in the direction close to the cutout during solder reflow is suppressed.

FIG. 5 is a cross-sectional view of the third land 113 in a portion where the cutout is not formed, and both ends of the third land 113 largely protrude from the third connection terminal 153 in the lateral direction. Therefore, the winding of the molten solder in the transverse direction of the end of the third connecting terminal 153 is sufficient, and from the both end side surfaces of the third connecting terminal 153 to the surface of the third land 113, the solder A fillet 165 is formed.

In this way, by sufficiently securing the amount of protrusion in the lateral direction of the third land 113 from both ends of the third connecting terminal 153, the solder fillet 165 is formed, and the third connecting terminal 153 and the third Mechanical strength for fixing the land 113 , that is, mechanical strength for fixing the electronic component 150 to the printed circuit board 105 may be secured.

Fig. 6 shows a cross-sectional view of a line segment C-C' in which a second connection terminal 152 is arranged in a second land 112 in which a fifth cut-out 125 is arranged on one side. Similarly to the third land 113 , a solder fillet is not formed in the vicinity of the fifth notch 125 , and extends from the side surface of the second connection terminal 152 to the second land 112 in the portion without the notch. Sufficient solder fillets 165 are formed.

As described above, in the portion where the notch is arranged in the land, the movement of the electronic component 150 during solder reflow can be suppressed. Further, even in the land where the cutouts are arranged, it is possible to form a solder fillet for holding the electronic component with sufficient strength except in the vicinity of the cutout.

As described above, according to the first embodiment of the present invention, the solder fillets surrounding the connection terminals of the electronic components are sufficiently formed on the mounting land, so that the electronic components are fixed to the printed board with sufficient mechanical strength, A high-density mounting module having good mounting position accuracy can be provided by suppressing the position at which the electronic component is fixed shifts over the molten solder during solder reflow and shifts away from the original position where it is aligned and mounted.

7 is a plan view showing another modified example of the first embodiment. In this further variant, at least four lands (211, 212, 213, 214) are included, with at least four required cut-outs (221, 222, 223, 224) and lands (211, 212, 213, 214). Each of them is distributed and arranged one by one. In the case of an electronic component having four or more connection terminals, it is more preferable that the cutouts are dispersedly arranged at positions spaced apart from each other.

<Second embodiment>

Fig. 8 is a plan view showing a second embodiment of the high-density mounting module of the present invention. Another modified example of this is to realize the solder structure of the first embodiment shown in Fig. 1 by an over-resist structure.

The module 101 includes a printed circuit board 105 having a first land 341 , a second land 342 , and a third land 343 . The printed circuit board 105 has a first connection terminal 151 and a second connection terminal 152 that are connected to the corresponding respective of the first land 341 , the second land 342 , and the third land 343 . and an electronic component 150 including a third connection terminal 153 is mounted thereon.

The surface of the printed circuit board 105 is covered with soldering resist. In this solder resist, a first opening 311 covering the periphery of the first land 341 and included in the region where the first land 341 is arranged is arranged, and in this first opening 311, the first opening 311 is provided. A first protrusion 321 protruding inward in the direction (X direction) is disposed. In addition, a second opening 312 covering the periphery of the second land 342 and included in the region where the second land 342 is disposed is also disposed, and the second opening 312 has a first direction (X direction). ) and a third protrusion 323 protruding inward in a second direction (Y direction) orthogonal to each other is disposed.

Further, in this solder resist, a third opening 313 covering the periphery of the third land 343 and included in the region where the third land 343 is arranged is arranged, and in this third opening 313, The second protrusion 322 protrudes in an orientation opposite to the first protrusion 321 in the first direction (X direction), and the third protrusion 323 protrudes in an orientation opposite to the third protrusion 323 in the second direction (Y direction) A fourth projection 324 is disposed.

In this second embodiment, the first lands 341 , the second lands 342 and By selectively printing cream solder on each surface of the third lands 343, solder reflow can be performed. At this time, no cream solder is formed on each of the protrusions 321 to 324 protruding inward of each of the openings 311 to 313 .

Further, while the solder is melted in the reflow process, the solder melted on each of the lands 341 to 343 flows only into the opening of the solder resist, so the planar shape of the solder after reflow is, to 313) in the same planar shape. Therefore, in 2nd Embodiment, it is possible to design the planar shape of the solder after reflow by making the shape of the opening part of a soldering resist a desired thing.

Also in the second embodiment, when the solder has the same planar shape as in the first embodiment shown in Fig. 1, the movement of electronic components suspended in the molten solder can be regulated during solder reflow. For example, when a force for moving in the negative direction of the first direction (X direction) is generated, the first protrusion 321 suppresses the movement of the first connection terminal 151 of the electronic component. And when the force to move in a positive direction arises, the 2nd protrusion part 322 suppresses the movement of the 3rd connection terminal 153 of an electronic component.

In addition, when a force to move in the negative direction of the second direction (Y direction) is generated, the third protrusion 323 suppresses the movement of the connection terminal 151 of the electronic component, and when a force to move in the positive direction is generated , that the second projection 322 suppresses the movement of the third connection terminal 153 of the electronic component can also be realized in the same manner as in the first embodiment shown in FIG. 1 .

Therefore, also in an overresist structure, by providing an inward projection part in the opening part of a soldering resist, the effect similar to the case of arranging the land which provided the cutout can be exhibited by designing the planar shape of solder.

As described above, according to the second embodiment, the solder fillets surrounding the connection terminals of the electronic components are sufficiently formed on the mounting land so that the electronic components are fixed to the printed board with sufficient mechanical strength and the electronic components are It is possible to provide a high-density mounting module having good mounting position accuracy by suppressing the fixed position from shifting from the original position mounted in alignment by moving over the molten solder during solder reflow.

101: module
105: printed board
111 to 113: first to third land
121-126: first to sixth cut-outs
150: electronic component
151 to 153: first to third connection terminals
165: solder fillet
301: module
305: printed board
311 to 313: first to third openings
321 to 324: first to fourth protrusions
341 to 343: first to third lands
351 to 353: first to third connection terminals
350: electronic component
X: first direction
Y: second direction

Claims (8)

a printed circuit board having a plurality of lands;
A high-density mounting module mounted on the printed circuit board and including an electronic component including a plurality of connection terminals connected to the plurality of lands,
The plurality of lands includes at least a first land and a second land, and the first land has a first notch extending in a first direction and a third notch extending in a second direction orthogonal to the first direction. is disposed, in the second land, the first notch extending in the first direction includes a second notch extending in the opposite direction from the first direction and the third notch extending in the second direction A fourth cutout extending in the opposite direction from the second direction is disposed,
and a solder fillet extending from each side surface of the plurality of connection terminals of the electronic component to a surface of each land to which the connection terminals are connected is formed. The method of claim 1,
The plurality of lands have lands in which cutouts are not disposed, the high-density mounting module. The method of claim 1,
In the plurality of lands, the first notch extending in the first direction is a fifth notch extending in the opposite direction from the first direction, and the third notch extending in the second direction is the second direction. A high-density mounting module, further comprising a third land on which a sixth cut-out extending in the same direction is disposed. 4. The method according to any one of claims 1 to 3,
The second land, the first cut-out extending in the first direction further includes a seventh cut-out extending in the same direction in the first direction, the high-density mounting module. a printed circuit board having a plurality of lands and a solder resist covering respective peripheral portions of the plurality of lands and having a plurality of openings included in respective regions of the plurality of lands;
A high-density mounting module mounted on the printed circuit board and including an electronic component including a plurality of connection terminals connected to the plurality of lands,
The plurality of openings included in the plurality of lands are opposite to each other in a first direction, a first protrusion and a second protrusion each protruding inward, and a second direction orthogonal to the first direction are opposite to each other, , each comprising a third protrusion and a fourth protrusion protruding inward,
and a solder fillet extending from each side surface of the plurality of connection terminals of the electronic component to a surface of each land to which the connection terminals are connected is formed. delete delete delete

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