Surface-mount electronic component and circuit board including the same

Abstract

The present application provides a surface mounting electronic component and a circuit substrate, which can inhibit the shift of mounting position in the short side direction of the electronic component. The surface mounting electronic component (1) comprises a main body (10) with a mounting surface (11) and terminal electrodes (20, 30) respectively arranged at both ends of the mounting surface (11) in the y direction. The terminal electrodes (20, 30) comprise a main area (21, 31) extending in the y direction and a protruding part (22, 32) arranged at the central part in the y direction and protruding from the main area (21, 31) to the end of the mounting surface (11) in the x direction. Thus, the protruding part (22, 32) arranged at the terminal electrode (20, 30) plays a role in positioning in the y direction during mounting, so that the shift of mounting position in the short side direction of the electronic component can be inhibited.

Description

Technical Field

[0001] The present invention relates to an electronic component ring including a circuit board of the electronic component, and particularly to a two-terminal surface-mount electronic component and a circuit board including the electronic component. Background Technology

[0002] Patent Document 1 discloses an electronic component with two terminals. The electronic component described in Patent Document 1 has terminal electrodes disposed at both ends in the long side direction.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2018-032812 Summary of the Invention

[0006] The technical problem that the invention aims to solve

[0007] However, when electronic components are miniaturized, the mounting position of the electronic component in the short side direction may shift due to misalignment of the solder resist layer on the substrate on which the electronic component is mounted. Such mounting position shifts are particularly noticeable in small two-terminal electronic components.

[0008] Therefore, the object of the present invention is to suppress the offset of the mounting position of the electronic component in the short side direction in a two-terminal surface-mount electronic component and a circuit board including the electronic component.

[0009] Technical solutions for solving technical problems

[0010] The surface-mount electronic component of the present invention includes: a main body having a mounting surface; a first terminal electrode disposed at one end of the mounting surface in the long side direction; and a second terminal electrode disposed at the other end of the mounting surface in the long side direction. The first terminal electrode and the second terminal electrode include: a main region extending in the short side direction of the mounting surface; and a protrusion disposed at the center of the short side direction and protruding from the main region to the end of the mounting surface in the long side direction.

[0011] According to the present invention, the protrusions provided on the first terminal electrode and the second terminal electrode serve to position the electronic component in the short side direction during installation, thereby suppressing the offset of the installation position of the electronic component in the short side direction.

[0012] In this invention, the length of the protrusion may be 30 μm or more, thereby forming a gap region of 30 μm or more between the main region and the end, where neither the first terminal electrode nor the second terminal electrode exists. This provides a sufficient positioning effect in the short-side direction.

[0013] In this invention, the main region can also be set across the entire width of the short side of the mounting surface. When the main region is set across the entire width of the short side of the mounting surface, it is easy for the mounting position to shift in the short side direction, but even in this case, the shift in the mounting position can be suppressed.

[0014] In this invention, the main body may also have a side surface located along its long side and orthogonal to the mounting surface, where neither the first terminal electrode nor the second terminal electrode is formed. This makes it easier to form the first and second terminal electrodes. Alternatively, the first and second terminal electrodes may further include a side portion disposed on the side surface and connected to a protrusion, the height of which in the direction perpendicular to the mounting surface is less than the height of the main body. This also helps to suppress offset of the mounting position of the electronic component along its long side.

[0015] The circuit board of the present invention includes: a substrate having a first pad pattern and a second pad pattern; the aforementioned surface-mount electronic component mounted on the substrate; and solder that connects the first pad pattern and the second pad pattern to a first terminal electrode and a second terminal electrode, respectively. The first pad pattern and the second pad pattern include: a main pattern portion that overlaps with a main region; and a sub-pattern portion that overlaps with a protrusion and has a smaller width in the short side direction compared to the main pattern portion.

[0016] According to the present invention, the protrusion on the terminal electrode side is positioned by using the sub-pattern portion on the substrate side, thereby suppressing the offset of the mounting position of the electronic component in the short side direction.

[0017] In this invention, the width of the main pattern portion in the short side direction may be smaller than the width of the main region in the short side direction. This suppresses solder exposure in the short side direction, thus enabling high-density mounting.

[0018] Invention Effects

[0019] Thus, according to the present invention, in a two-terminal surface-mount electronic component and a circuit board including it, it is possible to suppress the offset of the mounting position of the electronic component in the short side direction. Attached Figure Description

[0020] Figure 1 This is a general perspective view showing the appearance of the surface-mount electronic component 1 according to the first embodiment of the present invention.

[0021] Figure 2 This is a general top view showing the structure of mounting surface 11.

[0022] Figure 3 This is a general top view showing the structure of the main part of the substrate 3 on which the surface-mount electronic component 1 can be mounted.

[0023] Figure 4 This is a front view of a circuit board 4 consisting of a surface-mount electronic component 1 mounted on a substrate 3.

[0024] Figure 5 This is a side view of a circuit board 4 constructed by mounting surface-mount electronic components 1 on a substrate 3.

[0025] Figure 6 This is a schematic diagram illustrating the overlap between terminal electrodes 20 and 30 and pad patterns 40 and 50.

[0026] Figure 7 This is a schematic diagram showing the state in which the openings 61 and 62 of the solder mask layer 60 have shifted.

[0027] Figure 8 This is a general perspective view showing the appearance of the surface-mount electronic component 2 according to the second embodiment of the present invention.

[0028] Figure 9 This is a front view of a circuit board 5 constructed by mounting surface-mount electronic components 2 on a substrate 3. Detailed Implementation

[0029] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0030] Figure 1 This is a general perspective view showing the appearance of the surface-mount electronic component 1 according to the first embodiment of the present invention.

[0031] Figure 1 The surface-mount electronic component 1 shown is a two-terminal electronic component including a main body 10 with built-in functional components such as inductors, capacitors, and resistors, and terminal electrodes 20 and 30 disposed on the surface of the main body 10. The main body 10 has a generally cuboid shape with a mounting surface 11 and an upper surface 12 constituting the xy plane, side surfaces 13 and 14 constituting the yz plane, and side surfaces 15 and 16 constituting the xz plane. Terminal electrodes 20 and 30 are disposed on the mounting surface 11.

[0032] Figure 2 This is a general top view showing the structure of mounting surface 11.

[0033] like Figure 2As shown, in the mounting surface 11, the x-direction is defined as the long side direction. A terminal electrode 20 is provided at one end of the long side direction, and a terminal electrode 30 is provided at the other end of the long side direction. The terminal electrode 20 includes a main region 21 extending along the y-direction, which is the short side direction, and a protrusion 22 located at the center of the short side direction and protruding from the main region 21. Similarly, the terminal electrode 30 includes a main region 31 extending along the y-direction, which is the short side direction, and a protrusion 32 located at the center of the short side direction and protruding from the main region 31. Thus, both terminal electrodes 20 and 30 have a convex shape. In this embodiment, the terminal electrodes 20 and 30 are only provided on the mounting surface 11. Therefore, the terminal electrodes 20 and 30 are not formed on other surfaces such as the side surfaces 13 and 14.

[0034] The main regions 21 and 31 are provided across the entire width of the short side of the mounting surface 11. That is, the width of the main regions 21 and 31 in the y-direction is the same as the width of the mounting surface 11 in the y-direction. In contrast, the width of the protrusions 22 and 32 in the y-direction is narrower than the width of the mounting surface 11 in the y-direction. The protrusion 22 extends from the main region 21 to one end 17 of the mounting surface 11 in the x-direction. Similarly, the protrusion 32 extends from the main region 31 to the other end 18 of the mounting surface 11 in the x-direction. End 17 is the edge where the mounting surface 11 abuts against the side surface 13, and end 18 is the edge where the mounting surface 11 abuts against the side surface 14.

[0035] Using this structure, a gap region C is formed between the main regions 21, 31 and the ends 17, 18 where the terminal electrodes 20, 30 do not exist, and the protrusions 22, 32 are arranged such that the two gap regions C sandwich it from the y direction.

[0036] Figure 3 This is a general top view showing the structure of the main part of the substrate 3 on which the surface-mount electronic component 1 can be mounted.

[0037] The substrate 3, capable of mounting surface-mount electronic components 1, has pad patterns 40 and 50 and a solder resist layer 60. Openings 61 and 62 are provided in the solder resist layer 60, through which the pad patterns 40 and 50 are exposed. The exposed portion of the pad pattern 40 has a main pattern portion 41 and a sub-pattern portion 42. Similarly, the exposed portion of the pad pattern 50 has a main pattern portion 51 and a sub-pattern portion 52. The exposed portions of the pad patterns 40 and 50 have shapes corresponding to the terminal electrodes 20 and 30 of the surface-mount electronic components 1. That is, the sub-pattern portions 42 and 52 have a smaller width ratio in the y-direction compared to the main pattern portions 41 and 51, and are connected to the central portion in the y-direction of the main pattern portions 41 and 51.

[0038] Figure 4 and Figure 5These are the front view and side view of the circuit board 4, which is constructed by mounting surface-mount electronic components 1 on the substrate 3.

[0039] like Figure 4 and Figure 5 As shown, when the surface-mount electronic component 1 is mounted onto the substrate 3, the terminal electrodes 20 and 30 are connected to the pad patterns 40 and 50 respectively via solder 70. Figure 4 and Figure 5 In the example shown, the pad patterns 40 and 50 are slightly smaller in size compared to the terminal electrodes 20 and 30. Specifically, the width of the main pattern portions 41 and 51 in the x-direction is slightly smaller than the width of the main regions 21 and 31 in the x-direction, and the width of the main pattern portions 41 and 51 in the y-direction is also slightly smaller than the width of the main regions 21 and 31 in the y-direction. Similarly, the width of the sub-pattern portions 42 and 52 in the y-direction is also slightly smaller than that of the protrusions 22 and 32. Therefore, most of the solder 70 remains on the mounting surface 11, which serves as the bottom surface of the surface-mount electronic component 1, thus facilitating high-density mounting.

[0040] Figure 6 This is a schematic diagram illustrating the overlap between terminal electrodes 20 and 30 and pad patterns 40 and 50.

[0041] like Figure 6 As shown, when the surface-mount electronic component 1 is mounted on the substrate 3, the main region 21 and protrusion 22 of the terminal electrode 20 overlap with the main pattern portion 41 and sub-pattern portion 42 of the pad pattern 40, respectively, and the main region 31 and protrusion 32 of the terminal electrode 30 overlap with the main pattern portion 51 and sub-pattern portion 52 of the pad pattern 50, respectively.

[0042] Here, the protrusions 22 and 32 and the sub-patterned portions 42 and 52 serve to position the surface-mount electronic component 1 in the y-direction. This is because the solder 70 is not attached to the gap region C; therefore, the surface tension of the solder 70 located between the protrusions 22 and 32 and the sub-patterned portions 42 and 52 is used to center the surface-mount electronic component 1 in the y-direction. Thus, as... Figure 7As shown, even when the openings 61 and 62 of the solder mask layer 60 are offset in the y-direction, and thus a portion of the main pattern portions 41 and 51 are covered by the solder mask layer 60, the surface-mount electronic component 1 can be correctly positioned relative to the pad patterns 40 and 50 by utilizing the centering effect provided by the protrusions 22 and 32 and the sub-pattern portions 42 and 52. The problem of a portion of the main pattern portions 41 and 51 being covered by the solder mask layer 60 due to misalignment tends to occur when the difference between the width of the openings 61 and 62 in the y-direction and the width of the main pattern portions 41 and 51 in the y-direction is small. This situation is more likely to occur when the width of the terminal electrodes 20 and 30 of the surface-mount electronic component 1 mounted on the substrate 3 in the y-direction is larger, especially when the terminal electrodes 20 and 30 are provided across the entire width of the mounting surface 11 in the y-direction.

[0043] Here, to achieve a sufficient centering effect, it is necessary to ensure, to a certain extent, the length of the protrusions 22 and 32 in the x-direction, i.e., the width of the gap region C in the x-direction. Specifically, a sufficient centering effect can be obtained by making the length of the protrusions 22 and 32 in the x-direction 30 μm or more, and a higher centering effect can be obtained by making the length of the protrusions 22 and 32 in the x-direction to about 50 μm. There is no upper limit to the length of the protrusions 22 and 32 in the x-direction, but when the length of the protrusions 22 and 32 in the x-direction is too long, the area of ​​the main regions 21 and 31 is reduced, and as a result, the bonding strength of the solder 70 may be reduced. Therefore, it is preferable to be 100 μm or less.

[0044] Thus, in the surface-mount electronic component 1 of this embodiment, the terminal electrodes 20 and 30 have convex shapes. Therefore, even if the solder mask layer 60 of the substrate 3 is misaligned, no offset relative to the pad patterns 40 and 50 will occur when the surface-mount electronic component 1 is mounted to the substrate 3, and it can be correctly centered in the y-direction. This effect can be achieved even for electronic components other than those with two terminals. However, in electronic components with more than two terminals, such as four-terminal electronic components, the mounting position is less prone to misalignment due to the surface tension of the solder obtained in each terminal electrode. In contrast, two-terminal electronic components, such as the surface-mount electronic component 1 of this embodiment, are prone to mounting position misalignment caused by the misalignment of the solder mask layer 60. However, if the surface-mount electronic component 1 of this embodiment is used, such mounting position misalignment can be prevented.

[0045] Figure 8 This is a general perspective view showing the appearance of the surface-mount electronic component 2 according to the second embodiment of the present invention.

[0046] Figure 8The surface-mount electronic component 2 shown differs from the surface-mount electronic component 1 of the first embodiment in that it has side portions 23 and 33 of terminal electrodes 20 and 30 respectively provided on the side portions 13 and 14 of the main body 10. Other basic structures are the same as those of the surface-mount electronic component 1 of the first embodiment; therefore, the same reference numerals are used to label the same elements, and repeated descriptions are omitted.

[0047] The side portions 23 and 33 of the terminal electrodes 20 and 30 are connected to the protrusions 22 and 32, respectively, and their positions in the y-direction are consistent with those of the protrusions 22 and 32. The height of the side portions 23 and 33 in the z-direction is sufficiently smaller than the height of the main body 10 in the z-direction. Specifically, it is preferably less than half the height of the main body 10 in the z-direction, and more preferably the width of the protrusions 22 and 32 in the x-direction.

[0048] Figure 9 This is a front view of a circuit board 5 constructed by mounting surface-mount electronic components 2 on a substrate 3.

[0049] like Figure 9 As shown, when a surface-mount electronic component 2 is mounted on the substrate 3, solder fillets 70 are formed on the side portions 23 and 33 of the terminal electrodes 20 and 30. The expansion of the fillets is limited by the boundaries of the sub-pattern portions 42 and 52 and the solder resist layer 60, i.e., the edges of the openings 61 and 62. Therefore, the mounting position of the surface-mount electronic component 2 in the x-direction can also be centered. Furthermore, regarding the gap between the surface-mount electronic component 2 and other electronic components mounted adjacent to it, the gap in the x-direction where wiring extends on the substrate 3 is necessarily more extensive than the space in the y-direction where there is no wiring. Therefore, high-density mounting is not hindered by the fillets 70.

[0050] The preferred embodiments of the present invention have been described above, but the present invention is not limited to the above embodiments. Various modifications can be made without departing from the spirit of the present invention, and these modifications are of course included within the scope of the present invention.

[0051] Explanation of reference numerals in the attached figures

[0052] 1, 2 Surface Mount Electronic Components

[0053] 3 substrate

[0054] 4, 5 Circuit boards

[0055] 10 Main Body

[0056] 11 Mounting surface

[0057] 12. Upper surface

[0058] 13-16 Side View

[0059] 17, 18 end

[0060] 20 and 30 terminal electrodes

[0061] Main areas 21 and 31

[0062] 22, 32 protrusions

[0063] 23, 33 Side profile

[0064] 40, 50 pad patterns

[0065] 41, 51 Main Pattern Section

[0066] Pattern sections 42 and 52

[0067] 60 Solder mask layer

[0068] 61, 62 Openings

[0069] 70 Solder

[0070] C. Gap region.

Claims

1. A circuit substrate, characterized by, Comprising: a substrate having a first land pattern and a second land pattern; a surface-mount electronic component mounted to the substrate and having a first terminal electrode and a second terminal electrode; and solder connecting the first land pattern and the second land pattern to the first terminal electrode and the second terminal electrode, respectively, the surface-mount electronic component includes a main body portion having a mounting surface and a plurality of side surfaces orthogonal to the mounting surface, the first terminal electrode is disposed on one end side in a long side direction of the mounting surface, the second terminal electrode is disposed on the other end side in the long side direction of the mounting surface, the first terminal electrode and the second terminal electrode include a main region extending in a short side direction of the mounting surface, and a protruding portion disposed at a central portion in the short side direction and protruding from the main region to an end portion of the mounting surface in the long side direction, none of the plurality of side surfaces forms the first terminal electrode and the second terminal electrode, the first land pattern and the second land pattern include a main pattern portion overlapping the main region, and a sub pattern portion overlapping the protruding portion and having a width in the short side direction smaller than that of the main pattern portion, a width of the main pattern portion in the short side direction is smaller than a width of the main region in the short side direction, a width of the sub pattern portion in the short side direction is smaller than a width of the protruding portion in the short side direction.

2. The circuit substrate according to claim 1, wherein: a length of the protruding portion is 30 μm or more, thereby forming a gap region of 30 μm or more in which the first terminal electrode and the second terminal electrode are not present between the main region and the end portion.

3. The circuit substrate according to claim 1 or 2, wherein: the main region is disposed over the entire width in the short side direction of the mounting surface. ​

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