JP2000165014A - Surface mounting electronic component - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a surface mounting electronic component having connection terminals wherein a sufficient solder fillet can be formed without lowering the mounting density, and a sufficient connection strength can be obtained. SOLUTION: Connection terminals 3 having recesses 3a in a plane shape are disposed as connection terminals. Connection terminals 3 having a U-shaped plane shape are disposed as connection terminals. This patent applies to a hybrid IC having elements 1 mounted on a board 2. Recesses 2a are formed at the periphery of the board 2 of the hybrid IC 10 having elements 1 mounted on the board 2, and the connection terminals 3 having recesses 3a in a plane shape are disposed on the back surface of the board 2 so as to follow the recesses 2a of the board 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surface-mounted electronic component, such as a surface-mounted hybrid IC, which is mounted on a surface of an object to be connected such as a printed circuit board via connection terminals.

[0002]

2. Description of the Related Art As a conventional surface mount type hybrid IC, for example, FIG.
As shown in the main part of FIG.
9A. A hybrid IC 60 (60a) having a prismatic connection terminal (chip terminal) 53 on the lower surface side of the device, or a columnar shape on the lower surface side of a substrate 52 on which the element 51 is mounted as shown in FIG. IC 60 provided with connection terminals 53
(60b). And such a hybrid I
C60a and 60b usually connect the connection terminal 53 to the solder fillet 54 (FIG. 9A,
Via (b)), it is surface-mounted by electrically and mechanically connecting to a land 56 formed on the surface of the printed circuit board 55 to be connected.

[0003] A solder fillet 54 formed by reflow soldering is formed around the connection terminal 53. The size of the solder fillet 54 is as follows.
It is almost determined by the area of the bottom of the connection terminal 53 and the area of the land 56 formed on the printed circuit board 55, and usually, a desired connection strength is obtained (that is, a desired solder fillet 54 is formed). The area of the land 56 is designed to be larger than the bottom area of the connection terminal 53.

However, in recent years, as the demand for high-density mounting has increased, the area of the land 56 has become smaller, and has a size slightly larger than the bottom area of the connection terminal 53. As a result, the solder fillet 54 formed in the reflow soldering process becomes small, and the connection strength between the connection terminal 53 and the land 56, that is, the hybrid IC 60 and the printed circuit board 55 is insufficient. There is such a problem that it falls off from the substrate 55.

[0005] In some applications, it is necessary to mount the hybrid IC by manual soldering using a soldering iron instead of the reflow soldering method. When soldering is performed using a soldering iron, as the mounting density increases, the distance L2 between the hybrid IC 60 and other elements (parts) 57 on the printed circuit board 55 decreases as shown in FIG. However, there is a problem that the tip of the soldering iron 58 cannot be brought into contact with the solder 59 due to contact with another element (component) 57 on the printed circuit board 55. This tendency increases as the height of the other element (component) 57 increases.

[0006] The tip of the soldering iron 58 is solder 5
When the distance L2 between the hybrid IC 60 and the other element (component) 57 is increased so as to reach No. 9, there is a problem that the mounting density is reduced.

The present invention solves the above-mentioned problems, and a surface-mount electronic component capable of obtaining a sufficient connection strength (mounting reliability) without lowering the mounting density. It is an object of the present invention to provide a surface-mount type electronic component capable of coping with high-density mounting without interference between the soldering iron and other elements even when soldering using a soldering iron. .

[0008]

In order to achieve the above object, a surface-mount type electronic component according to the present invention (claim 1) is provided on a surface of a mounting object such as a printed circuit board via a connection terminal. A mechanically connected surface mount electronic component,
It is characterized by comprising an electronic component main body and a connection terminal having a concave portion in a planar shape, disposed on the electronic component main body, and electrically and mechanically connected to a mounting object.

By providing connection terminals having concave portions in a planar shape as connection terminals to be electrically and mechanically connected to a mounting object, when soldering is performed using a method such as reflow soldering, molten solder is used. Accumulates in the concave portion of the connection terminal, it is possible to form a sufficient solder fillet at the connection portion between the connection terminal and the land without increasing the area of the land of the mounting object, thereby lowering the mounting density. Without this, sufficient connection strength can be ensured, and the reliability of mounting can be improved. In addition, the present invention can be applied not only to the case of mounting using a solder but also to the case of mounting using a conductive resin. In the present invention, there is no particular restriction on the specific shape of the concave portion of the connection terminal, and it is possible to adopt various shapes in which molten solder, conductive resin, and the like are easily accumulated.

According to a second aspect of the present invention, the connection terminal has a substantially U-shaped planar shape.

By using a connection terminal having a substantially U-shape in plan view, it is possible to obtain a connection terminal having a structure in which the outer peripheral distance is efficiently increased without increasing the plane area, and solder fillets are easily accumulated. Becomes possible,
The present invention can be made more effective.

Further, the surface-mounted electronic component according to a third aspect is characterized in that the electronic component body is a hybrid IC in which elements are mounted on a substrate.

By applying the present invention to a hybrid IC in which elements are mounted on a substrate, it is possible to mount the hybrid IC at high density while securing the mounting reliability.

According to a fourth aspect of the present invention, the electronic component body is a hybrid IC in which an element is mounted on a substrate, and the peripheral portion of the substrate has a recess in a planar shape. A connection terminal is provided, and a concave notch is formed in a portion corresponding to a concave portion of the connection terminal in a peripheral portion of the substrate.

By providing a connection terminal having a concave portion on the peripheral portion of the substrate constituting the hybrid IC, and forming a concave cutout in a portion of the peripheral portion of the substrate corresponding to the concave portion of the connection terminal. Also, when soldering using a soldering iron, insert the soldering iron from the recesses of the board and the connection terminal to the vicinity of the joint between the land of the connection target such as a printed board and the connection terminal, Soldering can be performed reliably. Therefore, it is not necessary to increase the distance from other elements as in the related art, and even when the height of surrounding elements is high,
Since the soldering iron can be inserted into the vicinity of the joint between the land and the connection terminal, it is possible to cope with high-density mounting. There is no particular restriction on the specific shape of the concave cutout, and it is possible to adopt various shapes into which a soldering iron can be inserted.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described, and features thereof will be described in more detail. Here, a surface-mounted hybrid IC will be described as an example of the surface-mounted electronic component.

FIG. 1 is a perspective view showing a main part of a surface mount type hybrid IC according to an embodiment of the present invention.
FIG. 3 is a perspective view showing a structure of a connection terminal provided on a substrate constituting the hybrid IC.

The hybrid IC 10 is formed by mounting various elements 1 on a substrate 2.
Are formed with a plurality of concave portions (notched portions) 2a in the peripheral portion thereof. Then, a concave portion (notch portion) 2 in the peripheral portion of the substrate 2
As shown in FIG. 2, on the lower surface side of the portion where a is formed,
A connection terminal (length L, width W) 3 having a concave portion 3a having a width M and a depth N and a U-shape in plan view is provided.

In this embodiment, a connection terminal 3 formed by bending a metal plate having a thickness T and a width H and having good solder wettability is used. Further, as a method of attaching the connection terminal 3 to the substrate 2, various methods such as a method of mounting it on the substrate simultaneously with other elements by an automatic mounting machine and performing reflow soldering, a method of attaching using a conductive resin, and the like are used. be able to.

As the substrate 2, a substrate made of a copper-clad laminate made of resin and glass fiber as a base material, or an aluminum thick film printed substrate made of ceramic as a base material is used. The width M1 and the depth N1 of the concave portion 2a formed in the peripheral portion of the substrate 2 are formed to be substantially the same as the width M and the depth N of the concave portion 3a of the connection terminal 3.

FIG. 3 shows lands 21 on a printed circuit board 20 to which the connection terminals 3 of the hybrid IC 10 of this embodiment are connected. FIG. 4 shows the lands 21 on the connection terminals 3 and the solder fillets 22.
(See FIG. 5), a printed circuit board (mounting object) 2
FIG. 2 shows a state where the device is mounted by being connected to a land 21 formed at zero.

In this embodiment, the land 21 formed on the printed board 20 has a length L1 and a width W1 slightly smaller than the length L and the width W of the connection terminal 3, as shown in FIG. It is formed large.

In this hybrid IC 10, since the U-shaped connection terminal 3 having the concave portion 3a is provided, for example, when mounted by reflow soldering, as shown in FIG. Since the solder accumulates in the concave portion 3a, it is possible to form a sufficient solder fillet 22 by making the area of the land 21 of the printed circuit board 20 approximately the same or slightly larger than that of the connection terminal 3, A sufficient connection strength can be ensured without lowering the mounting density, and mounting reliability can be improved.

Also, when the length L1 and the width W1 of the land 21 formed on the printed circuit board 20 are the same as or smaller than the length L and the width W of the connection terminal 3, a U-shape is obtained. Since the solder accumulates in the concave portions 3a of the connection terminals 3, necessary connection strength can be secured.

In the hybrid IC 10, a concave portion 2 a is formed in the peripheral portion of the substrate 2, and the U-shaped connection terminal 3 is located at the position of the concave portion 2 a formed on the substrate 2. As shown in FIG. 6, even when soldering is performed using the soldering iron 31, the soldering iron 31 is placed almost directly above Through the concave portion 2a of the substrate 2 and the concave portion 3a of the connection terminal 3 to the junction between the connection terminal 3 and the land 21.
The soldering can be reliably performed using the soldering iron 31 without increasing the distance L2 (FIG. 6) between the C10 and the other elements 7. Therefore, it is possible to cope with high-density mounting. In this case, the dimensions of the concave portion 2a of the substrate 2 and the concave portion 3a of the connection terminal 3 need to be large enough to insert the tip of the soldering iron 31.

FIGS. 7 (a), 7 (b), 7 (c) and 7 (d)
In the hybrid IC according to the embodiment of the present invention,
FIG. 4 is a perspective view showing a mode of disposing connection terminals 3 on a substrate 2.
In the present invention, as shown in FIGS. 7A, 7B, 7C and 7D, connection terminals can be arranged in various modes. However, as described above, when soldering is performed using a soldering iron, as shown in FIG. 7A, the peripheral edge of the substrate 2 is arranged such that the opening of the concave portion 3a of the connection terminal 3 faces outward. It is necessary to arrange in the department.

In the above-described embodiment, an example was described in which the connection terminal 3 was formed by bending a metal plate having a thickness T and a width H and having good solder wettability. The shape of the connection terminal is not limited to this, and as shown in FIG.
It is also possible to use a thin metal plate that is bent to form a hollow columnar structure. Also in this case, a solder fillet is formed around after mounting (after soldering), so that it can sufficiently function as a connection terminal. Further, the shape of the connection terminal is not limited to the U-shape, and can be variously changed according to the land shape, such as a V-shape or a U-shape.

Further, as the connection terminal, a material in which the surface of a non-conductive material such as ceramic or resin is coated with a metal or other conductive material can be used.
In addition, the present invention can be widely applied when various solders such as eutectic solder and high-temperature solder are used at the time of mounting, and can also be applied when mounting using a conductive resin. It is.

In the above embodiment, the hybrid I
C has been described as an example.
The present invention is not limited to C, and can be applied to various other surface mount electronic components.

The present invention is not limited to the above embodiment in other respects, and various applications and modifications can be made within the scope of the present invention.

[0031]

As described above, the surface mount type electronic component of the present invention (claim 1) has a connection terminal having a concave portion in a planar shape as a connection terminal electrically and mechanically connected to a mounting object. When mounting using a method such as reflow soldering, the molten solder accumulates in the recess of the connection terminal, so the connection between the connection terminal and the land can be performed without increasing the land area of the mounting object. A sufficient solder fillet can be formed in the portion, and a sufficient connection strength can be secured without lowering the mounting density, and the reliability of mounting can be improved.

In the case where the connection terminal is formed in a substantially U-shape as the connection terminal as in the surface mount electronic component of the second aspect, the outer peripheral distance can be efficiently extended without increasing the plane area. As a result, it is possible to obtain a connection terminal having a structure in which a solder fillet easily accumulates, so that the present invention can be made more effective.

Further, when the present invention is applied to a hybrid IC having an element mounted on a substrate as in the case of the surface mount electronic component of the third aspect, the hybrid IC can be made high while ensuring sufficient connection strength. It becomes possible to implement density mounting.

According to a fourth aspect of the present invention, a connection terminal having a concave portion is provided on a peripheral portion of a substrate constituting a hybrid IC, and a connection terminal having a concave portion is provided.
When a concave notch is formed in the portion corresponding to the concave portion of the connection terminal, even when soldering using a soldering iron, the soldering iron is printed from the substrate and the concave portion of the connection terminal. The soldering can be reliably performed by inserting even the vicinity of the joint between the connection terminal and the land of the connection target such as the substrate. Therefore, it is not necessary to increase the distance between other elements as in the past, and even when the height of the surrounding elements is high, the soldering iron is joined almost directly from above to the connection between the land and the connection terminal. Since it can be inserted into the vicinity of the part, it is possible to cope with high-density mounting.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a main part of a surface mount type hybrid IC according to an embodiment of the present invention.

FIG. 2 is a hybrid IC according to an embodiment of the present invention.
FIG. 4 is a perspective view showing a structure of a connection terminal constituting the device.

FIG. 3 is a hybrid IC according to an embodiment of the present invention.
FIG. 4 is a perspective view showing the shape of a land on a printed circuit board on which the terminals are mounted together with connection terminals.

FIG. 4 is a hybrid IC according to an embodiment of the present invention.
FIG. 3 is a perspective view showing a state where is mounted on a printed circuit board.

FIG. 5 is a hybrid IC according to an embodiment of the present invention.
FIG. 4 is a perspective view showing a state where solder fillets are accumulated in concave portions of the connection terminals of FIG.

FIG. 6 is a hybrid IC according to an embodiment of the present invention.
FIG. 5 is a perspective view showing a state in which the connection terminals constituting the above are soldered to the lands of the printed circuit board using a soldering iron.

FIGS. 7 (a), (b), (c) and (d) are perspective views showing the arrangement of connection terminals of the hybrid IC according to the embodiment of the present invention.

FIG. 8 is a hybrid IC according to an embodiment of the present invention.
FIG. 6 is a perspective view showing another example of the connection terminal used for the first embodiment.

FIGS. 9A and 9B are perspective views showing a main part of a conventional surface-mount type hybrid IC.

FIG. 10 shows a conventional hybrid IC mounted.
FIG. 3 is a diagram illustrating a positional relationship between a hybrid IC and other elements (parts).

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Element 2 Substrate 2a Depression formed in substrate 3 Connection terminal 3a Depression of connection terminal 10 Hybrid IC 20 Printed circuit board 21 Land 22 Solder fillet L Connection terminal length L1 Land length L2 Hybrid IC and other elements Spacing W Width of connection terminal W1 Width of land M Width of recess of connection terminal M1 Width of recess of substrate N Depth of recess of connection terminal N1 Depth of recess of substrate

Claims (4)

[Claims] 1. A surface of a mounting object such as a printed circuit board,
A surface-mounted electronic component that is electrically and mechanically connected via a connection terminal, comprising: an electronic component main body; a recess having a planar shape, disposed in the electronic component main body, and mounted on a mounting object. A surface-mounted electronic component comprising: a connection terminal that is electrically and mechanically connected. 2. The surface-mounted electronic component according to claim 1, wherein said connection terminal has a substantially U-shaped planar shape. 3. The surface-mounted electronic component according to claim 1, wherein the electronic component body is a hybrid IC having an element mounted on a substrate. 4. A hybrid IC in which the electronic component main body has an element mounted on a substrate, wherein a connection terminal having a concave portion in a planar shape is provided on a peripheral portion of the substrate. 4. The surface-mounted electronic component according to claim 3, wherein a concave notch is formed in a portion of the peripheral edge of the substrate corresponding to the concave portion of the connection terminal.