JPH04131024U - surface mount electronic components - Google Patents

Abstract

(57) [Summary] [Purpose] The purpose is to provide a thin surface-mounted electronic component that can relax and absorb thermal or mechanical strain. [Structure] This is a structure in which highly elastic lead terminals are bonded to the lead electrodes of a thin chip-type electronic component with lead electrodes provided on the surface. In addition, the extraction electrodes 11 to 11 are provided on the top surface.
The lead terminals 21 to 24 are electrically and mechanically connected to the lead-out electrodes of the thin chip-type crystal resonator 1 provided with the lead terminal 14, and the lead terminals are bent approximately 90 degrees downward.
Further, it is bent outward at approximately 90 degrees at a position substantially flush with the bottom surface of the chip-type crystal resonator 1.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

This invention relates to thin surface-mounted electronic components, especially for mounting on printed wiring boards. It is related to the electronic components considered.

0002

[Conventional technology]

As electronic devices become smaller, electronic components have a lower overall height and are mounted on printed wiring boards. high-density mounting is required, and the mounting can be done by automatic machines. is required. To meet this demand, we have made electronic components thinner and leadless. There was a sudden movement towards chip type. Chip-type electricity as shown in Figure 7 The child component 7 is a hermetic crystal oscillator 9 typified by a popular type crystal oscillator 9 as shown in FIG. Compared to electronic components that use sealed containers, the overall height and volume are smaller. be able to. Note that 8 is a printed wiring board. Chip formation as shown in Figure 7 The extracted electronic components have an extraction electrode on the bottom surface, and this extraction electrode It was connected to external electrodes such as printed wiring boards. This connection is In the trend of assembly automation, electrical and mechanical attachment of electronic components to printed wiring boards Bonding is increasingly performed by reflow soldering. reflow Soldering is a process in which an appropriate amount of solder is supplied to the joint in advance, and then solder is applied from the outside. This method uses a heat source to melt the solder and perform soldering.

0003

[Problem that the idea aims to solve]

Chip-type electronic components can generally be made thinner and lower in profile, and as mentioned above, It is firmly electrically and mechanically bonded to the printed wiring board by soldering or the like. However, Lee Because it is a dress, there is no risk of shrinkage distortion during solder curing or deformation of the board. It does not have a part where the strain caused by the strain is alleviated. For example, some electronic devices have electronic components. After mounting on a printed wiring board, deformation of this board may be corrected. Also, electric Most subcomponents are equipped with a heat support to ensure or verify reliability. Cycle tests and aging tests are being conducted. What is heat cycle test?Electronic section Change the ambient temperature of the product, for example -40℃ → 25℃ for 3 minutes → 100℃ for 30 minutes → 25℃ A cycle of 3 minutes at Celsius and 30 minutes at -40C is repeated several hundred times. However By repeating such a cycle, the bonding material such as solder expands and contracts. blood In cases like these, top-type electronic components do not have parts that alleviate strain. . As a result, the package on the electronic component side may be cracked, or the contact with each component may be damaged. The conductive state could become unstable due to peeling of the mating surface.

0004 This invention was devised to solve the above problems, and is designed to prevent thermal or mechanical strain. The purpose is to provide a thin surface-mounted electronic component that can absorb and absorb be.

[0005]

[Means to solve the problem]

In order to solve the above problems, the surface-mounted electronic component according to the present invention is A highly elastic material is used as the lead-out electrode of a thin chip-type electronic component equipped with a lead-out electrode. It is characterized in that lead terminals are joined.

[0006] As an example of a surface-mounted electronic component that has a crystal resonator mounted on it, an extraction electrode is installed on the top surface. A lead terminal is joined to the extraction electrode of the thin chip-type crystal resonator that has been cut, This lead terminal is bent down about 90 degrees, and then bent again about 90 degrees. I can list some configurations.

[0007]

[Effect]

Highly elastic lead terminals are bonded to the lead electrodes of thin chip-type electronic components. , since the tip of this lead terminal connects to the electrode of the printed wiring board, chip-type electronic Lead terminals interposed between the component and the printed wiring board alleviate thermal and mechanical strain. As long as the lead terminals do not protrude significantly above the chip-type electronic components, low-profile The condition will not be affected.

[0008]

【Example】 Next, the present invention will be explained using a crystal resonator as an example with reference to the drawings. FIG. 1 is a perspective view showing a first embodiment of the present invention, and FIG. 2 is a front view of FIG. 1. . In the chip-type crystal resonator 1, a crystal resonator piece with electrodes formed therein is housed in the internal space. The electrodes drawn out from there are electrically connected to the lead-out electrodes 11, 12, 13, and 14. are connected to each other. These extraction electrodes 11, 12, 13, 14 are chip-type crystal It is provided on the top surface of the actuator 1 (generally chip-type crystal units have a drawer on the bottom surface). However, when such a chip-type crystal resonator is used upside down, Good too. ). The lead terminals 21, 22, 23, and 24 each have a plate-shaped metal plate approximately It is bent 90 degrees downward and is flush with the bottom of the chip type crystal resonator. It has a configuration in which it is bent approximately 90 degrees in a direction different from the bending direction. These lead terminals are joined to the extraction electrodes by brazing or the like. Furthermore, this The direction in which the lead terminals are bent is determined depending on the mounting form or space available for electronic components. All you need to do is to set the area and finally create a part that is parallel to the printed wiring board.

[0009] The second embodiment will be explained by taking a chip type crystal oscillator as an example. Figure 3 shows another embodiment. FIG. 4 is a front view of FIG. 3. The chip type crystal oscillator 3 has a voltage inside it. Contains a pole-formed crystal vibrating piece and necessary circuit components. And this example In this case, extraction electrodes 31 and 32 (partially omitted) are provided on the side surface of a chip-type crystal oscillator. ing. The lead terminals 41, 42, 43, and 44 have hook-shaped connecting parts with the extraction electrodes. The printed wiring board connection part is bent outward. These lead terminals are joined to the extraction electrodes by brazing or the like.

0010 A third embodiment will be described with reference to FIGS. 5 and 6. Figure 5 is a perspective view, Figure 6 is a normal view of Figure 5. It is a front view. The chip type crystal oscillator 5 has electrodes formed inside it as in the second embodiment. Contains a crystal vibrating piece and necessary circuit parts. And in this example, Output electrodes 51, 52, 53, and 54 are provided on the top surface of the chip type crystal oscillator. . The lead terminals 61, 62, 63, and 64 are U-shaped, and are connected to the lead electrodes. Joined by welding etc. When the lead terminal is attached, the lead end The tip of the crystal oscillator extends below the chip-type crystal oscillator.

[0011] Note that the present invention is not limited to the above embodiments, but can be applied to chip-type electronic components. It is widely applicable. Also, the direction in which the lead terminals extend is also above the chip-type electronic component. As long as it does not protrude too much towards the side, the low profile will not be compromised, so it can be used in a variety of configurations. can be achieved.

0012

[Effect of the idea]

Highly elastic lead terminals are bonded to the lead electrodes of thin chip-type electronic components. , since the tip of this lead terminal connects to the electrode of the printed wiring board, chip-type electronic Lead terminals interposed between the component and the printed wiring board alleviate thermal and mechanical strain. Therefore, the connection between the electronic components and the printed wiring board may become unstable, or Large strains on electronic components can cause damage such as cracking of the components. That's no longer the case. In addition, since thin chip-type electronic components are used, the lead end Even if a child is attached, the thickness will not increase significantly, and it can be mounted on a printed wiring board. It is possible to ensure the low profile required for the electronic components mounted thereon.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing a first embodiment of a chip-type electronic component according to the present invention.

FIG. 2 is a front view of FIG. 2.

FIG. 3 is a perspective view showing a second embodiment of the chip-type electronic component according to the present invention.

FIG. 4 is a front view of FIG. 3.

FIG. 5 is a perspective view showing a third embodiment of the chip-type electronic component according to the present invention.

FIG. 6 is a front view of FIG. 5.

FIG. 7 is a perspective view showing a conventional example.

FIG. 8 is a perspective view showing another conventional example.

[Explanation of symbols]

1 Chip type crystal oscillator 11, 12, 13, 14, 31, 32 Extraction electrode 21, 22, 23, 24, 41, 42, 43, 44, 6
1, 62, 63, 64 lead terminals 3, 5 Chip-type crystal oscillator 7 Chip-type electronic component 8 Printed wiring board 9 Crystal resonator

Claims (2)

[Scope of utility model registration request] 1. A surface-mounted electronic component characterized in that a lead terminal with high elasticity is bonded to a lead-out electrode of a thin chip-type electronic component having a lead-out electrode on its surface. 2. A lead terminal is bonded to the lead-out electrode of a thin chip-type crystal resonator having lead-out electrodes provided on the upper surface, and the lead terminal is bent downward by about 90 degrees,
A surface-mounted electronic component characterized by being bent by about 90 degrees.