JPH04111780U - electronic parts equipment - Google Patents

Abstract

(57) [Summary] [Purpose] In the mounting structure of heat-generating electronic components mounted on a printed circuit board that has wiring layers on two sides, surface mounting The present invention provides an electronic component device whose purpose is to reduce the temperature rise of heat-generating electronic components. [Structure] A soldering land is provided on the part of the printed circuit board where heat generating electronic components are mounted, and a through hole is provided from this part to the conductor wiring part on the bottom surface.Furthermore, the through hole is filled with solder and mounted on the top surface of the printed circuit board. The heat generated by the heat-generating components is transferred to the conductor wiring section on the lower surface, thereby reducing the temperature rise of the heat-generating components.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

This invention applies to heat-generating electronic components, such as active components such as transistors, diodes, and FETs. Related to the mounting structure of passive components such as resistors, inductors, etc. on printed wiring boards. It is.

0002

[Conventional technology]

Conventionally, when mounting the electronic components exemplified above on a printed wiring board, the electronic components shown in FIG. A similar structure was used. In Figure 1, 1 is a heat-generating electronic component, and 2 is a heat-generating electronic component. electrode, 3 printed wiring board, 4 soldering land for surface mounting, 5 conductor wiring, 6 is solder. As shown in Fig. 1(a), a heat generating electronic component 1 is mounted on a soldering land 4 for surface mounting and is half-mounted. It is fixed by the field 6. In the mounting structure configured in this way, the main component of the heat-generating electronic component is The important heat dissipation path is as indicated by the arrow in Figure 1(b) (1) The surface of the heat generating electronic component 1 and the (2) dissipates into the atmosphere from the component mounting surface of the printed wiring board 3; This can be divided into two types: radiation from the lower surface of the printed wiring board 3 into the atmosphere; this In (2) heat dissipation from the bottom of the board, its effectiveness depends on the thermal conductivity of the printed wiring. When using a printed wiring board with low thermal conductivity, heat-generating parts temperature rise has become large, and the upper operating temperature limit of the product must be lowered. Ta.

0003

[Purpose of invention]

This invention eliminates the drawbacks of the conventional structure mentioned above and allows heat to flow from the top surface to the bottom surface of the printed wiring board. The aim is to reduce the temperature rise of heat-generating electronic components by improving conduction. Ru.

0004

[Explanation of the structure and function of the device]

FIG. 2 is a structural diagram showing an embodiment of the present invention, in which 1 is a heat-generating electronic component, and 2 is a heat-generating electronic component. electrode, 3 printed wiring board, 4 soldering land for surface mounting, 5 conductor wiring, 6 7 is a through hole whose conductive layer is filled with solder. In FIG. 2, the solder land is formed by the solder 6 located on the top surface of the printed wiring board 3. The heat generated by the heat-generating electronic component 1 fixed to the printed wiring board 3 is The lower surface of the printed wiring board and the lower It is transmitted to the conductor wiring 5 provided on the surface and can be efficiently dissipated. That is, the heat transfer of the solder filled inside the through hole 7 provided in the printed wiring board 3 is Because the conductivity is sufficiently high compared to the thermal conductivity of the printed wiring board itself, this solder is Used as a means of transmitting heat generated in child parts to reduce the temperature rise of heat-generating electronic parts. can be done. In order to obtain a sufficient effect with this mounting structure, the shape of the heat-generating electronic component 1 must be It can be applied not only to parts for insertion mounting, but at least heat-generating parts. must be in contact with the printed wiring board surface. In addition, the position where the through hole 7 is placed is inside the soldering land 4 for surface mounting, or The area where the parts shown in the plan view of FIG. 3 come into contact with the printed wiring board 3 is It is necessary to make the area within the area 8 widened by the distance equal to the plate thickness. In addition, the external shape of the through hole is not limited to a circular shape, and can be arbitrarily selected such as a polygon or an ellipse, but a circular In some cases, if the diameter of the hole exceeds 1.5 times the thickness of the printed wiring board, it may be difficult to fill it with solder. Otherwise, the purpose of the present invention cannot be achieved. For non-circular holes, plot the shortest hole distance. By setting the thickness to 1.5 times or less than the thickness of the lint wiring board, almost equivalent effects can be obtained. subordinate Therefore, when mounting electronic components with a large contact area, increasing the number of through holes Provides effective heat dissipation. In addition, various modifications and additions may be made within the scope of the gist of the present invention. Any changes made to this invention shall be included in the rights to this invention.

[0005]

[Effect of the idea]

As described above, the mounting structure of the present invention can reduce the temperature rise of heat-generating electronic components. Therefore, it is possible to improve the quality and reliability of products, and it can be used in electronic circuit devices for industrial use. The above effect is great.

[Brief explanation of drawings]

[Figure 1(a)] Conventional mounting structure of heat-generating electronic components

[Figure 1(b)] Diagram explaining the heat dissipation path in the conventional structure

[Figure 2(a)] Plan view of the mounting structure of the heat-generating electronic component of the present invention

[Figure 2(b)] Side view of the mounting structure of the heat-generating electronic component devised by Wood

[FIG. 3(a)] Side view of another embodiment of the present invention

[FIG. 3(b)] Plan view of another embodiment of the present invention

[Explanation of symbols]

1 Heat-generating electronic component 2 Electrode of heat-generating electronic component 3 Printed wiring board 4 Soldering land for surface mounting 5 Conductor wiring 6 Solder 7 Through-hole 8 whose internal conductor layer is filled with solder 8 Arrangement area of through-hole

Claims (3)

[Scope of utility model registration request] Claim 1: In a printed wiring board having at least two wiring layers, a through hole having a conductive layer inside is provided in a soldering land for surface mounting of an electronic component to be mounted, and the through hole A heat generating electronic component device characterized in that the inside is filled with solder. 2. In a printed wiring board having at least two wiring layers, the area where the mounted electronic components come into contact with the printed wiring board is within an area expanded in four directions by the thickness of the printed wiring board, 1. A heat generating electronic component device, characterized in that a through hole having a conductive layer therein is arranged and the through hole is filled with solder. 3. The heat generating electronic component device according to claims 1 and 2, wherein the diameter of the through hole having a conductive layer therein is 1.5 times or less the thickness of the plate.