JP3543320B2 - Mounting structure of electric circuit device - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a mounting structure of an electric circuit device, and more particularly to a mounting structure of an electric circuit device suitable for efficiently dissipating heat of a heat-generating component of a high-frequency power amplifier.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, in a device such as a high-frequency power amplifier for a micro radio or a mobile radio base station, a structure for dissipating heat generated from a mounted heat-generating component and shielding a high-frequency signal has been used. FIG. 2 is an exploded perspective view showing a mounting structure of a conventional high-frequency power amplifier. In a conventional high-frequency power amplifier, a high-frequency board 29, a high-frequency signal input connector (hereinafter, RF IN) 25, a high-frequency signal output connector (hereinafter, RF OUT) 26, A structure in which a heat-generating component 27 and a feedthrough capacitor 30 are mounted, a lid 21 is mounted on an upper part of a case 22 having a bottom, a radiator 24 is mounted on a lower part of the case 22 having a bottom, and a substrate 23 is further mounted on a terminal of the feedthrough capacitor 30. It has become.
[0003]
In the mounting structure of the conventional high-frequency power amplifier shown in FIG. 2, since the high-frequency portion and the non-high-frequency portion are separated by the bottomed case 2, the substrate 23 and the high-frequency In order to connect the use substrate 29, it is necessary to attach the feedthrough capacitor 30 to the bottomed case 22.
[0004]
On the other hand, as a mounting structure of a high-frequency power amplifier which does not require a feedthrough capacitor and integrates a high-frequency portion and a non-high-frequency portion, there has conventionally been one shown in FIG. FIG. 3 is an exploded perspective view showing a mounting structure of another conventional high-frequency power amplifier. In another conventional high-frequency power amplifier, a heat-generating component 37 is mounted in a component mounting hole 41 of a substrate 33, RF IN 35 and RF OUT 36 are mounted on a high-frequency line 39 of the substrate 33, and a case in which there is no bottom above the substrate 33 ( Hereinafter, a bottomless case 38 is attached, a lid 31 is attached to an upper portion of the bottomless case 38, and a radiator 34 is attached to a lower portion of the substrate 33.
[0005]
On the other hand, even in the mounting structure of a CPU and peripheral components mounted on a device such as a personal computer or a workstation, signal processing exceeding 1 GHz is executed without using a feedthrough capacitor. Such a mounting structure was used.
[0006]
[Problems to be solved by the invention]
However, the conventional example described above has the following problems.
[0007]
In the mounting structure of the conventional high-frequency power amplifier as shown in FIG. 2, since the high-frequency portion and the non-high-frequency portion are separated by the bottomed case 22, the shielding effect of the high-frequency signal can be ensured as described above. On the other hand, in order to connect the substrate 23 and the high-frequency substrate 29, it is necessary to attach the feedthrough capacitor 30 to the bottomed case 22. For this reason, the number of assembling steps and parts costs have been increased. In addition, since the bottomed case 22 is provided between the heat-generating component 27 and the radiator 24, the thermal resistance in heat conduction is increased, and the radiation efficiency is deteriorated.
[0008]
On the other hand, in the mounting structure of another conventional high-frequency power amplifier as shown in FIG. 3, the substrate 33 is not divided into a high-frequency part and a non-high-frequency part. It was necessary to use an expensive high-frequency substrate material up to the high-frequency portion. Alternatively, in order to reduce the cost, it is necessary to use a substrate material having a large loss at high frequencies up to the high-frequency portion, and it has been difficult to compensate for the conflicting advantages of the two.
[0009]
In addition, in the mounting structure of the high frequency power amplifier of the conventional example shown in FIG. 3, when attaching the high frequency signal connectors (RF IN 35, RF OUT 36), it means that the ground of the high frequency line 39 is surely converted. In order to prevent the leakage of the high frequency signal, the respective end faces of the bottomless case 38, the board 33, and the radiator 34 are aligned so as to be located on the same plane, and are brought into contact with the outer conductor on the normal ground side of the RF OUT 36. There is a need. In order to further secure the contact, the ground is accurately placed between the respective end faces of the bottomless case 38, the substrate 33, and the radiator 34, and the outer conductor of the RF OUT 36 with a metal fitting having a spring property interposed therebetween. I sometimes take it. For this reason, the number of assembling man-hours and parts costs have increased.
[0010]
When the RF IN 35 and the RF OUT 36 are mounted on the surfaces facing each other, the bottomless case 38, the substrate 33, and the radiator 34 are made to have the same size in order to align the end faces, and the processing accuracy is increased so that there is no displacement. There is a need. For this reason, the mounting positions of the RF IN 35 and the RF OUT 36 have been limited, and the processing cost has been high.
[0011]
On the other hand, the mounting structure of a microprocessor mounted on a computer device such as a personal computer also has disadvantages such as poor heat dissipation efficiency and large assembly man-hours and parts cost, as described above.
[0012]
The object of the present invention is to efficiently dissipate heat, reduce assembly man-hours, reduce parts costs, improve high-frequency characteristics, reduce board costs, and eliminate the need to increase the processing accuracy of bottomless cases and radiators. It is intended to provide a mounting structure of the electric circuit device according to the present invention.
[0013]
[Means for Solving the Problems]
The present invention relates to a mounting structure of an electric circuit device including a substrate, a high-frequency substrate, a circuit element, and a radiator, wherein the substrate is sandwiched between the radiator and a case, and a heat-generating component as the circuit element is mounted on the substrate. Directly attached to the radiator through the component mounting hole provided in the above, the high-frequency board is mounted in the component mounting hole of the substrate, and a high-frequency connector as the circuit element is provided through the cable mounting hole provided in the case. It is characterized in that it is connected to the high-frequency board by a coaxial SJ cable.
[0014]
In addition, the mounting structure of the electric circuit device of the present invention will be described with reference to FIG. 1. The mounting structure of the electric circuit device including the substrate (3), the high-frequency substrate (9), the circuit element, and the radiator (4) In the structure, the substrate is sandwiched between the radiator and the case (8), and the heat-generating component (7) as the circuit element is connected to the radiator through a component mounting hole (11) provided in the substrate. Direct mounting, mounting the high-frequency board in the component mounting hole of the board, and connecting the high-frequency connector (6) as the circuit element with the SJ cable (12) through a cable mounting hole (14) provided in the case. Connect to high frequency board.
[0015]
[Action]
In the mounting structure of the electric circuit device according to the present invention, the heat-generating component is directly attached to the radiator. Therefore, heat can be efficiently dissipated. Further, unlike the related art, it is not necessary to provide a feedthrough capacitor for connecting the substrate and the high-frequency substrate, so that the substrate material can be selectively used for the high-frequency portion and the non-high-frequency portion. For this reason, it is possible to reduce the number of assembling steps, the cost of parts, the improvement of high-frequency characteristics, and the cost of boards. Further, since the high-frequency line ground conversion between the high-frequency board and the high-frequency connector is performed via the SJ cable, it is not necessary to perform the ground conversion by aligning the respective end surfaces of the case, the board, and the radiator, and the spring property is improved. It is no longer necessary to sandwich the bracket with For this reason, the number of assembly steps and the cost of parts can be reduced. Furthermore, as described above, since the high-frequency line ground conversion between the high-frequency board and the high-frequency connector is performed via the SJ cable, it is not necessary to align the respective end faces of the case, the board, and the radiator. This eliminates the need to adjust the size of the radiator to the case as in the related art. Therefore, the degree of freedom of the mounting position of the high-frequency connector is increased, and it is not necessary to increase the processing accuracy of the case and the radiator.
[0016]
BEST MODE FOR CARRYING OUT THE INVENTION
[This embodiment]
Next, embodiments of the present invention will be described in detail with reference to the drawings.
[0017]
(1) Description of Configuration The mounting structure of the high-frequency power amplifier according to the embodiment of the present invention is particularly applied to a high-frequency (several 100 MHz to several tens GHz) high-output (several W to several tens W or more) power amplifier. It is preferable that a heat-generating component such as a high-frequency transistor of a power amplifying element, a power-amplifying field-effect transistor (hereinafter, PWR FET) or an absorption resistor of an isolator is directly attached to a radiator, and an SJ cable is used to connect a high-frequency signal connector to a board. The feature is that it is used.
[0018]
FIG. 1 is an exploded perspective view showing a mounting structure of a high-frequency power amplifier according to an embodiment of the present invention. The high-frequency power amplifier according to the embodiment of the present invention is mounted on an electronic device, and includes a lid 1, a board 3, a radiator 4, a coaxial connector RF IN5, RF OUT6, a heat-generating component 7, a bottomless case 8, a high-frequency board. 9, an SJ cable 12 and a cable holder 13 are provided. In the figure, reference numeral 11 denotes a component mounting hole of the substrate 3, 14 denotes a cable mounting hole of the bottomless case 8, 15 denotes a high-frequency line of the substrate 3, and 16 denotes a high-frequency line of the high-frequency substrate 9. Reference numeral 17 denotes a notch for holding down the RF IN5.
[0019]
More specifically, the component mounting hole 11 is formed in the substrate 3. The high-frequency substrate 9 is mounted in the component mounting hole 11 of the substrate 3, and the RF IN 5 is mounted on the longitudinal end of the substrate 3. Can be The board 3 is mounted on the radiator 4, and the heat generating component 7 of the power amplifying element is directly mounted through the component mounting hole 11 of the board 3. The bottomless case 8 is mounted on the upper part of the substrate 3, and a cable mounting hole 14 through which the SJ cable 12 connected to the end of the RF OUT 6 can penetrate is formed in the longitudinal end face of the bottomless case 8. I have.
[0020]
The RF OUT 6 is attached to the outside of the bottomless case 8, and the SJ cable 12 passes through the cable attachment hole 14 and is attached to the radiator 4 by the cable retainer 13 and is attached to the high-frequency board 9. The SJ cable 12 is formed by forming the inner conductor and the outer conductor of a core wire with a coaxial tube using a copper material or plating the same with a 50Ω impedance, and filling a coaxial cable with Teflon or the like as a coaxial cable between the core wire and the outer conductor. Alternatively, the core wire and the outer conductor are fixed by arranging Teflon spacers at a predetermined interval as a semi-credit, and have flexibility such as bending. Since the outer conductor can be soldered and can be grounded as a ground potential, it also has a heat radiation effect and can also diffuse heat to the outside through the RF OUT 6 of the coaxial connector.
[0021]
The lid 1 is attached to the upper part of the bottomless case 8. More specifically, the substrate 3 is attached in a state sandwiched between the bottomless case 8 and the radiator 4. The substrate 3 is provided with a large number of conduction holes, and the side surface of the substrate 3 is configured by metal plating or the like so that high-frequency leakage does not occur. The lid 1 is mounted on the upper part of the bottomless case 8 and shields the bottomless case 8 in high frequency. Here, by forming the component mounting holes 11 in the substrate 3, the heat generating components 7 can be directly mounted on the radiator 4 as described above. The heat generating component 7 includes an isolator, a power absorption resistor, and the like in addition to the PWR FET.
[0022]
The RF IN 5 serving as an input-side connector is attached from the side surface of the board 3, is provided with a notch 17 so that the core of the signal line does not contact the bottomless case 8, and is connected to the high-frequency line 15 of the board 3. You. RF OUT 6, which is an output-side connector, is connected to high-frequency substrate 9 by SJ cable 12. Here, the inner conductor that is the core wire of the SJ cable 12 is connected to the high-frequency line 16 of the high-frequency board 9, and the outer conductor of the SJ cable 12 is attached to the radiator 4 by the cable holding bracket 13 and dropped to the ground. Have been.
[0023]
(2) Description of Operation Next, the operation of the embodiment of the present invention will be described in detail with reference to FIG.
[0024]
In the mounting structure of the high-frequency power amplifier according to the embodiment of the present invention, since the component mounting hole 11 is formed in the substrate 3 as shown in FIG. 1, the heat generating component 7 can be directly mounted on the radiator 4. it can. In addition, since the SJ cable 12 is used to connect the RF OUT 6 and the high-frequency board 9, the outer conductor of the RF OUT 6 only needs to be brought into contact with the bottomless case 8 only. Thereby, efficient heat radiation of the heat-generating component 7 becomes possible. Further, it is not necessary to align the respective end faces of the bottomless case 8, the substrate 3, and the radiator 4 so as to be located on the same plane as in the related art.
[0025]
That is, according to the embodiment of the present invention, by forming the component mounting holes 11 in the substrate 3, the heat generating component 7 can be directly mounted on the radiator 4, whereby the heat can be efficiently radiated. Is obtained.
[0026]
Further, unlike the related art, there is no need to provide a feedthrough capacitor for connecting the substrate 3 and the high-frequency substrate 9, so that the substrate material can be selectively used in the high-frequency portion and the non-high-frequency portion, thereby reducing the number of assembly steps. It also has the effect of reducing parts costs, improving high-frequency characteristics, and reducing board costs.
[0027]
Furthermore, since the high-frequency line ground conversion between the high-frequency board 9 and the RF OUT 6 is performed via the SJ cable 12, it is necessary to perform the ground conversion by aligning the respective end faces of the bottomless case 8, the board 3, and the radiator 4. This eliminates the need to interpose a metal fitting having spring properties, thereby reducing the number of assembly steps and the cost of parts.
[0028]
Furthermore, as described above, the high-frequency line ground conversion between the high-frequency substrate 9 and the RF OUT 6 means that the ground potential is accurately secured at a high frequency, and the grounding is performed via the SJ cable 12. Since there is no need to align the respective end surfaces of the case 8, the substrate 3, and the radiator 4, it is not necessary to adjust the size of the radiator 4 to the bottomless case 8 as in the related art. There is also an effect that the degree of freedom is increased, and it is not necessary to increase the processing accuracy of the bottomless case 8 and the radiator 4.
[0029]
[Other embodiments]
The present invention may be embodied in the following other embodiments in addition to the above embodiment.
[0030]
In another embodiment of the present invention, the basic configuration is as shown in FIG. 1. In the embodiment of FIG. 1, only the high-frequency signal output connector (RF OUT) 6 is connected by the SJ cable 12. Although the present invention has been applied, the present invention is not limited to this, and as another embodiment, a high-frequency signal input connector (RF IN) 5 or another high-frequency connector (for example, a high-frequency signal monitoring using a directional coupler) Connector).
[0031]
In the embodiment of FIG. 1 described above, the outer conductor of the SJ cable 12 is attached to the radiator 4 by the cable retainer 13, but the present invention is not limited to this. Twelve outer conductors may be attached to the substrate 3 by soldering. In this case, the component mounting hole 11 is not opened at the position where the SJ cable 12 is mounted. This eliminates the necessity of attaching the cable retainer 13, thereby achieving an effect of further reducing the number of assembling steps and parts cost. Alternatively, the outer conductor of the SJ cable 12 can be attached to the radiator 4 with a conductive adhesive.
[0032]
Further, in the embodiment shown in FIG. 1, the high-frequency substrate 9 is used only for the output portion. However, the present invention is not limited to this, and in another embodiment, particularly, only the output portion is required. However, it can be used in places where it is desired to reduce the loss of other high-frequency signals.
[0033]
Furthermore, in the embodiment of FIG. 1, the mounting structure of the high-frequency power amplifier mounted on the electronic device has been described as an example. However, the present invention is not limited to this. The present invention is also applicable to a mounting structure of a CPU or a drive IC mounted on a workstation or the like.
[0034]
【The invention's effect】
As described above, according to the present invention, in a mounting structure of an electric circuit device including a substrate, a high-frequency substrate, a circuit element, and a radiator, the substrate is sandwiched between the radiator and a case, and the circuit element A heat-generating component is directly mounted on the radiator through a component mounting hole provided on the substrate, the high-frequency substrate is mounted on the component mounting hole of the substrate, and a high-frequency connector as the circuit element is provided on the case. Since the structure is such that the SJ cable is connected to the high-frequency board via the cable mounting hole, the following effects can be obtained.
[0035]
The heat-generating component can be directly attached to the radiator, thereby providing an effect of efficiently dissipating heat.
[0036]
Further, unlike the conventional case, there is no need to provide a feedthrough capacitor for connecting the substrate and the high-frequency substrate, and the substrate material can be selectively used for the high-frequency portion and the non-high-frequency portion, thereby reducing the number of assembling steps and the component cost. This also has the effect of reducing the cost, improving the high frequency characteristics, and reducing the cost of the substrate.
[0037]
Further, since the high-frequency line ground conversion between the high-frequency board and the high-frequency connector is performed via the SJ cable, it is not necessary to perform ground conversion by aligning the respective end faces of the case, the board, and the radiator. Therefore, it is not necessary to sandwich the metal fitting having the shape, and as a result, the effects of reducing the number of assembly steps and the cost of parts can be obtained.
[0038]
Furthermore, as described above, since the high-frequency line ground conversion between the high-frequency board and the high-frequency connector is performed via the SJ cable, there is no need to align the respective end faces of the case, the board, and the radiator. This eliminates the need to adjust the size of the radiator to the case as in the related art, thereby increasing the degree of freedom in the mounting position of the high-frequency connector and eliminating the need to increase the processing accuracy of the case and the radiator.
[Brief description of the drawings]
FIG. 1 is an exploded perspective view showing a mounting structure of a high-frequency power amplifier according to an embodiment of the present invention.
FIG. 2 is an exploded perspective view showing a mounting structure of a conventional high frequency power amplifier.
FIG. 3 is an exploded perspective view showing a mounting structure of another conventional high-frequency power amplifier.
[Explanation of symbols]
1 Lid 3 Substrate 4 Heatsink 5 RF IN
6 RF OUT
Reference Signs List 7 Heating component 8 Bottomless case 9 High frequency board 11 Component mounting hole 12 SJ cable 13 Cable holding bracket 14 Cable mounting hole 15, 16 High frequency line

Claims (7)

In a mounting structure of an electric circuit device including a substrate, a high-frequency substrate, a circuit element, and a radiator,
The substrate is sandwiched between the radiator and the case, and a heat-generating component as the circuit element is directly mounted on the radiator through a component mounting hole provided in the substrate, and the high-frequency substrate is mounted on the component of the substrate. A mounting structure for an electric circuit device, wherein the mounting device is mounted in a mounting hole, and a high-frequency connector as the circuit element is connected to the high-frequency board by an SJ cable of a coaxial tube through a cable mounting hole provided in the case. The inner conductor of the SJ cable is connected to a high-frequency line of the high-frequency board, and the outer conductor of the SJ cable is attached to the radiator by metal fittings through the component mounting hole of the board. The mounting structure of the electric circuit device according to 1. 2. The mounting structure according to claim 1, wherein an inner conductor of the SJ cable is connected to a high-frequency line of the high-frequency board, and an outer conductor of the SJ cable is attached to the board by soldering. The electric circuit device according to claim 1, wherein an inner conductor of the SJ cable is connected to a high-frequency line of the high-frequency board, and an outer conductor of the SJ cable is attached to the radiator with a conductive adhesive. Mounting structure. 4. The method according to claim 1, wherein the side surface of the substrate is formed by metal plating or the like so as not to leak at a high frequency, and a lid for shielding the case at a high frequency is attached to an upper portion of the case. A mounting structure of the electric circuit device according to any one of the above. The mounting structure of an electric circuit device according to any one of claims 1 to 5, wherein the mounting structure is applicable to a high-frequency power amplifier mounted on an electronic device. The mounting structure of the electric circuit device according to claim 1, wherein the mounting structure is applicable to a power amplifier mounted on an audio device.

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