JPH06169189A - Chip type heat generating component and packaging thereof - Google Patents

Abstract

PURPOSE:To provide a packaging method, which forms a high-heat generating component into a chip and at the same time, dissipates efficiently heat generated in the component to the outside. CONSTITUTION:A chip type heat generating component 1 is provided with an electrode 3 for heat dissipation and heat generated in the component is dissipated from the electrode to a ground layer 7, which is an internal layer of a printed board 6, via a pad 5 for heat dissipation electrode on the board 6. Moreover, the layer 7 is taken out from the end face of the board 6 to the outside, is connected to a heat sink 9 and finally, the heat is dissipated from the sink 9 into the air.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a chip-type heat-generating component provided with an efficient heat-dissipating means for mounting a high-heat-generating component typified by a resistor on the surface of a chip and a mounting method thereof.

[0002]

2. Description of the Related Art A typical example of mounting a conventional high heat generating electronic component is shown in FIG. High heat electronic components 1
0 is connected to the conductor layer circuit 11, and the heat generated in the high heat generating electronic component 10 is transferred to the high heat conductive metal base substrate 13 and radiated. However, the metal base substrate used in this method is expensive and has a problem that the component mounting and wiring areas are limited, and thus there is a problem that it cannot be applied to a general multi-layer substrate that houses a logic unit. As a related publicly known example, for example, JP-A-60-167399 (60.8.3).
0) can be mentioned.

[0003]

Since the electric power that can be applied to the chip component is determined by the material used and the temperature rise value of the self, the smaller the external shape of the component is, the more the temperature rise due to heat generation. The characteristics are greatly deteriorated.
Further, when the high heat-generating component is made into a chip and surface-mounted, expansion / contraction due to heat generation significantly reduces the reliability of the solder connection portion. Therefore, by improving the heat dissipation efficiency from the chip component body and suppressing the temperature rise, it is possible to make the high power component into a chip and downsize it.

[0004]

A heat-dissipating electrode is provided separately from a functional electrode for solder connection, which is required as an original function, in a chip-type heat-generating component. The heat dissipation electrode is provided close to the heat generating element of the chip component so as to efficiently transfer heat from the heat generating element. In addition to the solder connection pads required for the original function on the printed circuit board side, a heat dissipation pad directly connected to the ground layer or power supply layer as a common inner layer of the printed circuit board is provided at a position corresponding to the heat dissipation electrode of the component. . Further, this inner layer surface is extended to the outside of the printed board by a direct or indirect means and is connected to a heat sink for heat radiation.

[0005]

The heat generated by the chip-type heat-generating component is radiated by radiation from a part of the surface and conduction from the functional electrode to the wiring pattern, but is transferred to the inner layer of the printed board through the heat-radiating electrode. The inner layer is usually a solid conductor as a common inner layer and has a large area so that it has a large heat capacity, and most of the heat from the components is transferred to this inner layer unless forced cooling from the outside. This may be sufficient when the heat generation amount of the entire printed circuit board is small, but when it is necessary to handle a larger amount of electric power, the heat amount of the inner layer is further extended to the outside through a heat sink or other structure.

[0006]

1 is a perspective view showing the structure of a chip-type heat-generating component according to an embodiment of the present invention. Chip type heat generating component 1
In addition to the functional electrodes 2 for electrical connection at both ends, the electrodes 3 for heat dissipation are provided on the side surface and the lower surface.

FIG. 2 is a sectional view showing the structure of a printed circuit board on which a chip-type heat-generating component according to an embodiment of the present invention is mounted. The printed circuit board 6 is provided with functional electrode pads 4, a ground layer 7 provided as an inner layer of the printed circuit board 6, and through holes 14 in consideration of thermal conductivity, at positions corresponding to the electrodes of the chip-type heat-generating component shown in FIG. The heat dissipation electrode pads 5 are connected to each other.

FIG. 3 is a sectional view showing a state in which a chip-type heat-generating component, which is an embodiment of the present invention, is mounted on a printed board. The functional electrode 2 and the heat-radiating electrode 3 of the chip-type heat-generating component 1 are soldered to the functional electrode pad 4 and the heat-radiating electrode pad 5 on the printed circuit board 6, respectively. Part of the heat generated in the chip-type heat-generating component 1 radiates from the surface and is also conducted from the functional electrode to the printed board through the pad,
Most of the heat is transmitted from the heat dissipation electrode 3 to the heat dissipation electrode pad 5 on the printed circuit board 6. Since the radiating electrode pad 5 is connected to the ground layer 7 which is the inner layer of the printed circuit board 6 through the through hole 14, the heat of the radiating electrode 5 is transferred to the ground layer 7. The ground layer 7 has an external connection portion 8 connected to the inner layer portion from the end face of the printed board 6, and a heat sink 9 is attached to the connection portion. As a result, the heat of the ground layer 7 is further transferred to the heat sink 9 through the external connection portion and radiated into the air. Here, the means for extending the ground layer 7 to the outside can be achieved, for example, by using a method of connecting the ground layer 7 and the conductor of the flexible printed circuit (FPC) at the inner end surface of the printed board 6. Here, it goes without saying that the heat sink may use a metal frame or the like inside the device as long as it has no electrical influence. Further, when the heat generation amount of the entire printed circuit board is small and the heat capacity of the ground layer has a margin, it is not necessary to take out the ground layer to radiate heat, or a small heat sink 9a is attached to a part of the printed circuit board 6 to ground. It is also possible to release the heat of the layer.

As described above, in this embodiment, the heat generated from the chip-type heat-generating component first escapes to the ground layer, which is the inner layer of the printed circuit board, through the heat-radiating electrode, so that even if there is a high-heat-generating component locally. Since the heat is evenly distributed over the entire substrate, it is not necessary to perform local cooling. Further, when the amount of heat generation is large, the temperature rise of the entire substrate can be suppressed by radiating heat from an external heat sink connected to the ground layer. Therefore, the thermal design of the printed circuit board is facilitated, and there is an effect that the reliability is improved and the circuit board is reduced in size / light weight / cost.

[0010]

The present invention has the following effects.

(1) Even for a component that generates a large amount of heat (for example, a resistor that consumes a large amount of power), it is possible to realize a chip that is optimal for downsizing the device.

(2) Since the local cooling of the high heat-generating components is not required in the entire apparatus, the forced cooling means such as a fan can be downsized or eliminated, and the apparatus can be made small and low in cost. There is also the effect of noise prevention by the fan.

[Brief description of drawings]

FIG. 1 is a perspective view of a chip-type heat-generating component showing an embodiment of the present invention.

FIG. 2 is a sectional view of a printed circuit board showing an embodiment of the present invention.

FIG. 3 is a cross-sectional view showing a mounted state showing an embodiment of the present invention.

FIG. 4 is a cross-sectional view showing a conventional technique.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Chip-type heat generating component, 2 ... Functional electrode, 3 ... Heat dissipation electrode, 4 ... Functional electrode pad, 5 ... Heat dissipation electrode pad, 6 ... Printed circuit board, 7 ... Ground layer, 8 ... External connection part, 9 ... Heat sink, 10 ... High heat generating electronic component, 11 ... Conductor layer circuit, 12 ... Insulating layer, 13 ... High heat conductive metal base, 14 ... Through hole.

Claims (3)

[Claims] 1. A chip component for surface mounting, comprising a main body portion having a function as a circuit element and an electrode having both electrical and mechanical connection, for heat dissipation provided for releasing heat generated in the main body portion. A chip-type heat-generating component characterized by having electrodes. 2. The chip-type heat-generating component mounting method according to claim 1, wherein the generated heat is transferred to a common inner layer of the multilayer printed circuit board through the heat-radiating electrodes. 3. A mounting method for a chip-type heat-generating component according to claim 2, wherein the common inner layer portion of the printed circuit board is extended to the outside, and heat is radiated through a heat sink provided at the extension destination.