JP2018014461A - Electronic circuit equipment - Google Patents

Abstract

To provide an electronic circuit device capable of easily releasing heat from a highly heat-generating component to a casing when the substrates arranged in an overlapping manner are connected with flexible terminals. A first substrate, a second substrate disposed so as to overlap the first substrate with a gap, and a flexible substrate provided on the second substrate and connected to the first substrate. A terminal portion; a high heat-generating component mounted on the second substrate and including a power semiconductor or a coil; a housing that houses the first substrate and the second substrate and to which the first substrate is fixed; and high heat generation A heat dissipating material provided between the component and the inner surface of the housing so as to be in contact with the highly heat-generating component and the housing, and provided between the first substrate and the second substrate. And a support column that maintains the distance between the two substrates at a predetermined distance or more. [Selection] Figure 2

Description

  The present invention relates to an electronic circuit device on which an electronic circuit including a component that generates a relatively large amount of heat, such as a power semiconductor, is mounted.

  There has been disclosed an integrated circuit package structure including a terminal portion that is connected to an end portion of a rigid substrate and is configured around a flexible substrate having flexibility (see Patent Document 1).

  According to such a configuration, by bending the terminal portion (flexible substrate), it is possible to connect the substrates that are arranged to be overlapped with each other at the terminal portion.

JP-A-6-338585

  In order to cool components with relatively large calorific value (hereinafter referred to as “high heat generation components”) such as power semiconductors and coils mounted on the substrate, a heat dissipation material is provided between the housing housing the substrate and the high heat generation components. In some cases, a structure in which heat is released from a highly heat-generating component to the housing may be employed. In this case, in order to accommodate the substrate in the housing so that a certain amount of pressing force acts on the heat radiating material from the high heat generating component and the housing, the heat radiating material depends on the pressing force acting on the high heat generating component and the housing. By being crushed, the thermal resistance is reduced, and heat is easily released from the highly heat-generating component to the housing.

  However, in the case of the configuration in which the substrates are connected using the flexible terminal portion, the flexible portion of the terminal portion bends. There is a possibility of lowering. Then, as the pressing force acting from the high heat generating component and the casing decreases, the heat resistance of the heat dissipating material increases. As a result, it becomes difficult for heat to escape from the high heat generating component to the casing, and the device falls into an overheated state. there is a possibility.

  Accordingly, in view of the above problems, an electronic circuit device capable of easily releasing heat from a highly heat-generating component to the housing when the substrates arranged to be overlapped with a gap are connected by a flexible terminal portion. The purpose is to provide.

In order to achieve the above object, in one embodiment of the present invention,
A first substrate;
A second substrate disposed so as to overlap with the first substrate;
A flexible terminal provided on the second substrate and connected to the first substrate;
A high heat-generating component mounted on the second substrate and including a power semiconductor or a coil;
A housing that houses the first substrate and the second substrate, and to which the first substrate is fixed;
A heat dissipating material provided between the high heat generating component and the inner surface of the housing so as to contact the high heat generating component and the housing;
A support column provided between the first substrate and the second substrate, and maintaining a distance between the first substrate and the second substrate at a predetermined distance or more.
An electronic circuit device is provided.

  According to one embodiment of the present invention, even when the flexible terminal portion is bent, the support post maintains the distance between the first substrate and the second substrate at a predetermined distance or more. A reduction in the pressing force acting on the heat radiating material from the high heat generating component and the housing is suppressed. Therefore, heat can be easily released from the highly heat-generating component to the housing.

  According to the present embodiment, an electronic circuit device capable of easily releasing heat from a highly heat-generating component to the housing when the substrates arranged to be overlapped with a gap are connected by a flexible terminal. Can be provided.

It is sectional drawing which shows an example of a structure of an electronic circuit apparatus roughly. It is a figure explaining the effect | action of an electronic circuit apparatus. It is a figure which shows an example of a structure of the electronic circuit apparatus which concerns on a comparative example.

  Hereinafter, embodiments for carrying out the invention will be described with reference to the drawings.

  First, the configuration of the electronic circuit device 1 according to the present embodiment will be described with reference to FIG.

  FIG. 1 is a cross-sectional view schematically showing an example of the configuration of an electronic circuit device 1 according to the present embodiment.

  The electronic circuit device 1 includes electronic circuit boards (hereinafter simply referred to as “substrates”) 10 and 20 on which electronic circuits for realizing predetermined functions are mounted, and a housing 50 that houses the boards 10 and 20. . The housing 50 includes a lower housing 51 that covers the substrates 10 and 20 from below and an upper housing 52 that covers the substrates 10 and 20 from above, and the lower housing 51 and the upper housing 52 are, for example, fitted. By being attached, a sealed internal space can be formed. The housing 50 is made of, for example, aluminum die casting and has a relatively high thermal conductivity. The electronic circuit device 1 may be a multi-phase DC-DC converter, for example. In this case, DC-DC converter circuits for the respective phases connected in parallel are mounted on the boards 10 and 20. Hereinafter, the electronic circuit device 1 will be described on the premise that it is a multi-phase DC-DC converter.

  The substrate 10 (an example of a first substrate) has a substantially flat plate shape and has a property of being hard and difficult to bend. The substrate 10 is, for example, a rigid glass epoxy substrate. The substrate 10 is fixed to the casing 50 by supporting the lower surfaces of the end portions thereof with the two support columns 30 standing on the bottom surface inside the casing 50 (lower casing 51). The support column 30 is made of, for example, aluminum and has a substantially cylindrical shape.

  The electronic circuit mounted on the substrate 10 includes, for example, a high heat generating component 15 having a relatively large heat generation amount such as a power semiconductor or a coil of a DC-DC converter circuit. The high heat generating component 15 is mounted on the lower surface of the substrate 10.

  A heat dissipating material 16 is disposed between the high heat generating component 15 and the bottom surface inside the housing 50 (lower housing 51) so as to contact the high heat generating component 15 and the lower housing 51. The heat dissipation material 16 is, for example, a heat dissipation sheet using an acrylic or silicon-based member. The heat dissipation material 16 is crushed according to the pressing force acting from the high heat-generating component 15 and the housing 50 (lower housing 51), so that the thermal resistance is lowered. For this reason, considering the thermal deformation (thermal expansion and contraction) and the like, the length of the support column 30 is appropriately set, so that the heat radiation member 16 is appropriately pressed from the high heat generating component 15 and the casing 50 (lower casing 51). The pressure acts and heat can be released from the highly heat-generating component 15 to the housing 50.

  Similar to the substrate 10, the substrate 20 (an example of a second substrate) has a substantially flat plate shape and has a property of being hard to bend. The substrate 20 is, for example, a rigid glass epoxy substrate. The substrate 20 is fixed to the substrate 10 by supporting the lower surface of the end portions thereof with two support columns 40 standing on the upper surface of the substrate 10. As a result, the substrate 20 is disposed so as to overlap the substrate 10 with a gap. The support column 40 is made of, for example, aluminum, like the support column 30, and has a substantially cylindrical shape.

  Moreover, the board | substrate 20 is provided with the two terminal parts 21 which have flexibility in the both ends. When the electronic circuits mounted on the boards 10 and 20 are connected in parallel as in the DC-DC converter circuit of each phase of the multi-phase DC-DC converter, it is necessary to electrically connect the boards 10 and 20 at two locations. Because there is. Each of the two terminal portions 21 includes a flexible substrate 22 having one end connected to the end of the substrate 20 and having flexibility, and a terminal 23 connected to the other end of the flexible substrate 22. By flexing the flexible substrate 22, the substrate 20 and the substrate 10 disposed under the substrate 20 can be electrically connected. Specifically, by bending the flexible substrate 22 connected to the end portion of the substrate 20, the terminal 23 provided on the other end portion of the flexible substrate 22 is inserted into the through hole of the substrate 10, and soldered or the like. The substrate 20 and the substrate 10 can be electrically connected.

  As in the case of the substrate 10, the electronic circuit mounted on the substrate 20 includes, for example, a high heat generating component 25 having a relatively large heat generation amount such as a power semiconductor or a coil of a DC-DC converter circuit. The high heat generating component 25 is mounted on the upper surface of the substrate 20.

  A heat dissipating material 26 is disposed between the high heat generating component 25 and the upper surface inside the housing 50 (upper housing 52) so as to be in contact with the high heat generating component 25 and the upper housing 52. The heat radiating material 26 is a heat radiating sheet using, for example, an acrylic or silicon-based member, like the heat radiating material 16. The heat dissipation material 26 is crushed according to the pressing force acting from the high heat-generating component 25 and the housing 50 (upper housing 52), so that the thermal resistance is lowered. For this reason, by taking into account thermal deformation (thermal expansion and contraction) and the like, the length of the support column 40 is appropriately set, so that the heat radiation member 26 is appropriately pressed from the high heat generating component 25 and the housing 50 (upper housing 52). The pressure acts and heat can be released from the highly heat-generating component 25 to the housing 50.

  Next, the operation of the electronic circuit device 1 according to the present embodiment will be described with reference to FIGS.

  First, FIG. 2 is a diagram for explaining the operation of the electronic circuit device 1 according to the present embodiment, that is, the operation by providing the column 40. Specifically, FIG. 2A is a diagram illustrating the action of force when assembled when the support column 40 is removed from the electronic circuit device 1, and FIG. 2B is a diagram illustrating when the electronic circuit device 1 is assembled. It is a figure which shows the effect | action of this force.

  2A and 2B, when the upper housing 52 is assembled to the lower housing 51 in a state where the substrate 10 connected to the substrate 20 and the terminal portion 21 is fixed to the lower housing 51, A pressing force acting on the heat radiating material 26 from the housing 50 (upper housing 52) is applied to the substrate 20.

  Here, as shown in FIG. 2A, when the support column 40 is not provided, there is a possibility that the flexible substrate 22 of the terminal portion 21 is further bent by the downward force applied to the substrate 20. Then, the substrate 20 on which the high heat generating component 25 is mounted moves downward, and the pressing force acting on the heat radiating material 26 from the high heat generating component 25 and the housing 50 (upper housing 52) decreases. As a result, the heat resistance increases, and as a result, it is difficult for heat to escape from the highly heat-generating component 25 to the housing 50, and the electronic circuit device 1 may fall into an overheated state.

  On the other hand, as shown in FIG. 2B, when the support column 40 is provided, since the support column 40 can receive a downward force applied to the substrate 20, the downward movement of the substrate 20 is suppressed. The That is, the column 40 has a predetermined distance (specifically, the thermal resistance of the heat dissipating material 26 is relatively low) even if the thermal deformation (thermal expansion and contraction) is taken into account. It can be maintained in a range that is equal to or greater than the minimum distance required for the predetermined reference. Therefore, the pressing force acting on the heat dissipation material 26 from the high heat generating component 25 and the housing 50 (upper housing 52) is appropriately maintained, and heat can easily escape from the high heat generating component 25 to the housing 50.

  In the present embodiment, the support column 40 is fixed to both the substrates 10 and 20, but either one of them can be used as long as the distance from the substrates 10 and 20 can be maintained above the predetermined distance. It may be a mode fixed only to the above. For example, the support column 40 may be fixed to the substrate 10 and there may be a gap between the lower surface of the substrate 20. Also in this case, by setting the length of the support column 40 as appropriate, the downward movement of the substrate 20 can be suppressed, and the same actions and effects as in the present embodiment can be obtained.

  Further, in the electronic circuit device 1 according to this embodiment, two support columns 40 are provided, but three or more support columns 40 may be provided. There may be. Also in this case, the downward movement of the substrate 20 can be suppressed, and the same actions and effects as in the present embodiment can be obtained.

  Further, in the electronic circuit device 1 according to the present embodiment, the substrates 10 and 20 are connected by the two terminal portions 21, but even when the substrates 10 and 20 are connected by the one terminal portion 21. By providing the support column 40, the same operation and effect as the present embodiment can be obtained.

  Next, FIG. 3 is a diagram illustrating an example of the configuration of the electronic circuit device 1c according to the comparative example.

  In addition, in the figure, the same code | symbol is attached | subjected to the structure similar to the electronic circuit device 1 which concerns on this embodiment.

  As shown in FIG. 3, in the electronic circuit device 1c according to the comparative example, the substrates 10 and 20 are stacked one above the other, and the substrates 10 and 20 are electrically connected. Is used.

  The pin header 60c includes a metal terminal 62c and a resin base 61c that covers an intermediate portion of the terminal 62c. The pin header 60c includes a stress relaxation portion 63c that is provided on the terminal 62c and suppresses a decrease in the life of the soldered portion due to stress generated at high and low temperatures. One end of each terminal 62c of the two pin headers 60c is inserted into the through hole of the substrate 10 and joined by soldering or the like, and the other end is inserted into the through hole of the substrate 20 and joined by soldering or the like. As a result, the substrates 10 and 20 are electrically connected.

  Thus, in the electronic circuit device 1c according to the comparative example, in order to electrically connect the substrates 10 and 20, it is necessary to use the two pin headers 60c which are connection parts. Further, in the electronic circuit device 1c according to the comparative example, two joining operations, that is, a total of four joining operations are required for each of the two pin headers 60c. In addition, since the electronic circuit device 1c according to the comparative example uses the pin header 60c that is hard and difficult to deform, it is necessary to provide the stress relaxation portion 63c on the terminal 62c, and the vertical dimension of the electronic circuit device 1c may be increased. There is.

  On the other hand, in the electronic circuit device 1 according to the present embodiment, as described above, the terminal portion 21 attached integrally to the end portion of the substrate 20 is provided. Therefore, since it is not necessary to use connection parts separately, the parts cost can be reduced, and each of the two terminal portions 21 is joined once, that is, a total of two joining operations, The substrates 10 and 20 can be electrically connected, and processing costs can be reduced. In the electronic circuit device 1 according to the present embodiment, the terminal portion 21 has flexibility as described above. Therefore, since the terminal portion 21 (flexible substrate 22) is bent, the stress of the soldering portion generated at a high temperature and a low temperature can be suppressed, and there is no need to separately provide a mechanism for relaxing the stress. The enlargement of the device 1 can be suppressed.

  In addition, when the substrates 10 and 20 are electrically connected at two locations as in the present embodiment, the relative misalignment (for example, the substrate 10 of the substrate 10) due to the manufacturing error of each component or the like. It is necessary to adopt a structure that can absorb the relative displacement of the through holes. As an example, a floating connector or the like can be used. However, since the structure is complicated, it is very expensive.

  On the other hand, in the electronic circuit device 1 according to the present embodiment, since the terminal portion 21 has flexibility as described above, it is relative to the two joint portions (two through holes in the substrate 10). Even if the position shift occurs, the terminal portion 21 (flexible substrate 22) can be flexed as appropriate. That is, it is possible to absorb the relative displacement between the two joint portions without adopting a special structure or component.

  As mentioned above, although the form for implementing this invention was explained in full detail, this invention is not limited to this specific embodiment, In the range of the summary of this invention described in the claim, various Can be modified or changed.

1 Electronic Circuit Device 10 Electronic Circuit Board (First Board)
15 High heat generation component 16 Heat dissipation material 20 Electronic circuit board (second board)
DESCRIPTION OF SYMBOLS 21 Terminal part 22 Flexible board 23 Terminal 25 High heat-generating component 26 Heat radiation material 30 Prop 40 Prop 50 Case 51 Lower case 52 Upper case

Claims (1)

A first substrate;
A second substrate disposed so as to overlap with the first substrate;
A flexible terminal provided on the second substrate and connected to the first substrate;
A high heat-generating component mounted on the second substrate and including a power semiconductor or a coil;
A housing that houses the first substrate and the second substrate, and to which the first substrate is fixed;
A heat dissipating material provided between the high heat generating component and the inner surface of the housing so as to contact the high heat generating component and the housing;
A support column provided between the first substrate and the second substrate, and maintaining a distance between the first substrate and the second substrate at a predetermined distance or more.
Electronic circuit device.

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