Electronic devices

Abstract

To provide an electronic device with improved heat dissipation.SOLUTION: An electronic device having signal wiring 100 comprises a substrate 1 which has one surface 1a and another surface 1b on the opposite side to the surface 1a, and is provided with the signal wiring formed on an insulating layer 101. On the same surface, on the insulating layer 101, where the signal wiring 100 is located, the substrate 1 is provided with heat dissipation wiring 150 to be thermally connected to the signal wiring 100. With the heat dissipation wiring disposed on the same surface where the signal wiring is located, the signal wiring and the heat dissipation wiring can be easily arranged close to each other. As a result, it becomes easier to dissipate heat from the signal wiring via the heat dissipation wiring, thus resulting in improvement in heat dissipation.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an electronic device having signal wiring. [Background technology]

[0002] Conventionally, electronic devices having signal wiring have been proposed. For example, Patent Document 1 proposes a power conversion device as an electronic device. Specifically, this power conversion device has a primary winding and a secondary winding as signal wiring, and an insulating plate is disposed between the primary winding and the secondary winding. In addition, this power conversion device has a heat dissipation plate disposed on the primary winding. And, this power conversion device is configured by stacking the secondary winding, the insulating plate, the primary winding, and the heat dissipation plate, and integrating them with a molding resin. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2019-165148 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, in such electronic devices, it is desirable to further improve the heat dissipation properties.

[0005] In view of the above, an object of the present invention is to provide an electronic device that can improve heat dissipation. [Means for solving the problem]

[0006] Claim 1 to achieve the above object, 2 , 8The electronic device has a signal wiring (100), and is provided with a substrate (1) having one surface (1a) and another surface (1b) opposite the first surface, on which the signal wiring is formed on an insulating layer (101). The substrate has a heat dissipation wiring (150) formed on the insulating layer and on the same plane as the signal wiring, and which is thermally connected to the signal wiring. In claim 1, the substrate is formed with through holes (101a, 101b) penetrating in the thickness direction, and a core (20) constituting a closed magnetic circuit is disposed at a position including the through holes, the substrate is a multilayer substrate in which a plurality of constituent layers (110, 120, 130, 140) are laminated, and the signal wiring has a winding (111, 121, 131, 141) wound around the through holes and a lead-out wiring (112, 122, 123, 132, 133, 142) connected to the winding in two or more constituent layers, and the winding is disposed in the surface direction of the substrate. In the present invention, the core is sandwiched between two portions of the heat dissipation wiring, the heat dissipation wiring is formed in a location including the periphery of the windings on both sides of the core in the surface direction, and is divided into an area on one side of the core and an area on the other side of the core based on a virtual line (K) that passes through the winding and extends along one direction in the surface direction of the substrate, and the heat dissipation wiring is divided into an area on one side of the core and an area on the other side of the core at a portion that overlaps with the core in a normal direction to the surface direction of the substrate. In at least one of the two or more constituent layers, one end of the winding is connected to a first end lead wiring (122, 132) and the other end is connected to a second end lead wiring (123, 133), and the second end lead wiring is electrically connected to a housing (2) made of a conductive material via a fastening member (60) and is connected to a heat dissipation wiring. . Claim 2In the embodiment, through holes (101a, 101b) are formed in the substrate in the thickness direction, and a core (20) constituting a closed magnetic circuit is disposed at a position including the through holes. The substrate is a multilayer substrate in which a plurality of constituent layers (110, 120, 130, 140) are laminated. The signal wiring is formed in two or more constituent layers, and includes windings (111, 121, 131, 141) wound around the through holes and lead-out wiring (112, 122, In at least one of the two or more constituent layers, the winding has one end connected to a first end lead wiring (122, 132) and the other end connected to a second end lead wiring (123, 133), which is electrically connected to a housing (2) made of a conductive material via a fastening member (60) and is connected to a heat dissipation wiring. Claim 8 In the substrate, the other side is arranged facing a housing (2) made of a conductive material, a heat dissipation member (81, 82) thermally connected to the signal wiring is arranged on at least one of the one side and the other side of the substrate, a heat dissipation member is arranged on one side of the substrate, and a pressing member (90) is arranged on the heat dissipation member, through holes (101a, 101b) are formed in the substrate to penetrate in the thickness direction, a core (20) that forms a closed magnetic circuit is arranged at a position including the through holes, and the pressing member has a support portion (90b) arranged on the heat dissipation member and a pressing portion (90c) integrated with the support portion to press the core.

[0007] According to this, the heat dissipation wiring is arranged on the same plane as the signal wiring, which makes it easy to arrange the signal wiring and the heat dissipation wiring in close proximity to each other, making it easier to dissipate heat from the signal wiring via the heat dissipation wiring, thereby improving heat dissipation.

[0008] The reference symbols in parentheses attached to each component indicate an example of the correspondence between the component and specific components described in the embodiments described below. [Brief description of the drawings]

[0009] [Figure 1] 1 is a perspective view of a power conversion device according to a first embodiment. [Diagram 2] FIG. 1 is a circuit diagram of a transformer. [Diagram 3] FIG. [Figure 4A] FIG. 2 is a plan view of a first component layer. [Figure 4B] FIG. 4 is a plan view of a second component layer. [Figure 4C] FIG. 4 is a plan view of a third component layer. [Figure 5A] FIG. 2 is a cross-sectional view taken along the line VA-VA in FIG. [Figure 5B] 2 is a cross-sectional view taken along line VB-VB in FIG. [Figure 6] 11A and 11B are diagrams for explaining problems that may occur when heat dissipation wiring is not divided. [Figure 7] FIG. 11 is an exploded perspective view of a transformer forming region in a modified example of the first embodiment. [Figure 8A] FIG. 11 is a plan view of a second component layer in the second embodiment. [Figure 8B] FIG. 11 is a plan view of a third component layer in the second embodiment. [Figure 9A] FIG. 13 is a plan view of a second component layer in the third embodiment. [Figure 9B] FIG. 13 is a plan view of a third component layer in the third embodiment. [Figure 10] FIG. 13 is a perspective view of a power conversion device according to a fourth embodiment. [Figure 11] 2 is an exploded perspective view of a pressing member, a one-side heat dissipation member, a transformer assembly area, and an other-side heat dissipation member. FIG. [Figure 12] FIG. 12 is a cross-sectional view taken along line XII-XII in FIG. [Figure 13] FIG. 13 is a perspective view of a power conversion device according to a fifth embodiment. [Figure 14] FIG. 13 is a perspective view of a power conversion device according to a modified example of the fifth embodiment. [Figure 15] 1A and 1B are diagrams for explaining problems that may occur when fixing a printed circuit board to a housing. [Figure 16]FIG. 13 is a schematic cross-sectional view of a power conversion device according to a sixth embodiment. [Figure 17] FIG. 13 is a schematic cross-sectional view of a power conversion device according to a modified example of the sixth embodiment. [Figure 18] FIG. 23 is a plan view of a first component layer in the seventh embodiment. [Figure 19] FIG. 23 is an exploded perspective view of a transformer forming region in the eighth embodiment. [Figure 20] FIG. 13 is a circuit diagram of a transformer according to another embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following embodiments, parts that are the same or equivalent to each other will be denoted by the same reference numerals.

[0011] (First embodiment) A first embodiment will be described with reference to the drawings. In this embodiment, a power conversion device having a transformer T will be described as an electronic device.

[0012] 1, the power conversion device of this embodiment includes a printed circuit board 1 and a housing 2. The printed circuit board 1 of this embodiment is a multi-layer board in which signal wiring 100 made of copper or the like and insulating layers 101 made of epoxy resin or the like are alternately laminated, and has one surface 1a and another surface 1b.

[0013] A predetermined portion of the printed circuit board 1 is defined as a transformer configuration area 10 that configures the coil of the transformer T, and a core 20 is provided in this transformer configuration area 10 to configure the transformer. Although omitted in Fig. 1, electronic components such as capacitors are appropriately mounted on the printed circuit board 1 in an area different from the transformer configuration area 10.

[0014] The transformer T of this embodiment has a configuration including first to third coils 31 to 33 as shown in FIG. 2. The first coil 31 has one end connected to a first connection line 41 and the other end connected to a second connection line 42, and is connected to an AC circuit (not shown) via the first connection line 41 and the second connection line 42. The second coil 32 and the third coil 33 are connected in series, and the third connection line 43 is connected to the end of the second coil 32 opposite to the third coil 33, and the fourth connection line 44 is connected to the end of the third coil 33 opposite to the second coil 32. The second coil 32 and the third coil 33 are connected to a rectifier circuit (not shown) via the third connection line 43 and the fourth connection line 44. In this embodiment, a fifth connection line 45 is connected between the second coil 32 and the third coil 33. The fifth connection line 45 is connected to the housing 2 and maintained at ground potential, as described later.

[0015] In the transformer forming region 10 of the printed circuit board 1, signal wiring 100 is formed so as to form the first to third coils 31 to 33 and the first to fifth connecting lines 41 to 45. Hereinafter, the transformer forming region 10 of this embodiment will be specifically described.

[0016] The transformer construction region 10 of this embodiment is configured by laminating first to fourth constituent layers 110, 120, 130, and 140 as shown in FIG. 3, FIG. 4A to FIG. 4C, FIG. 5A, and FIG. 5B. The transformer construction region 10 is configured as a part of the printed circuit board 1, and although an exploded perspective view is shown in FIG. 3, it is actually integrated. And, like the transformer construction region 10, the printed circuit board 1 is configured by laminating first to fourth constituent layers 140. However, hereinafter, when the first to fourth constituent layers 110, 120, 130, and 140 are simply described, it means the first to fourth constituent layers 110, 120, 130, and 140 in the transformer construction region 10.

[0017] The first to third constituent layers 110, 120, and 130 are configured to have a signal wiring 100 and an insulating layer 101. The fourth constituent layer 140 is configured to have a signal wiring 100. The signal wiring 100 in the first to fourth constituent layers 110, 120, 130, and 140 is appropriately electrically connected through connection vias 102 formed in the first to third constituent layers 110, 120, and 130. The fourth constituent layer 140 is configured by the signal wiring 100 formed on the insulating layer 101 in the third constituent layer 130 on the side opposite to the second constituent layer 120 side. Therefore, it can be said that the insulating layer 101 in the third constituent layer 130 is shared by the third constituent layer 130 and the fourth constituent layer 140.

[0018] In each of the first to third constituent layers 110, 120, and 130, one central through-hole 101a and two outer edge through-holes 101b are formed in the insulating layer 101, penetrating in the thickness direction. Specifically, the central through-hole 101a is formed in the approximate center of the first to third constituent layers 110, 120, and 130. The two outer edge through-holes 101b are arranged in the first to third constituent layers 110, 120, and 130 so as to sandwich the central through-hole 101a. More specifically, the central through-hole 101a and the outer edge through-hole 101b are formed in positions and sizes that allow the respective legs 21b, 21c, 22b, and 22c of the first core 21 or the second core 22, which will be described later, to be inserted therein.

[0019] In the first component layer 110, an upper primary winding 111 is formed on the insulating layer 101 as a signal wiring 100 that is wound around the central through-hole 101a and constitutes a part of the first coil 31 in the above-mentioned transformer T. The upper primary winding 111 of this embodiment has four turns and a line width that allows four turns, and is wound so as to include a space between the central through-hole 101a and the outer edge through-hole 101b.

[0020] In addition, in the first component layer 110, a first lead-out wiring 112 is formed as the signal wiring 100, which is led out from one end of the upper primary winding 111 on the side opposite to the central through hole 101a and constitutes the first connection line 41. In the first component layer 110, a third connection line wiring 113 and a fourth connection line wiring 114 are formed as the signal wiring 100 on the side opposite to the side on which the first lead-out wiring 112 is formed, sandwiching the central through hole 101a therebetween. The third connection line wiring 113 is connected to a third lead-out wiring 122 formed in the second component layer 120 described later through a connection via 102. The fourth connection line wiring 114 is connected to a fourth connection line wiring 124 formed in the second component layer 120 described later through a connection via 102.

[0021] The second component layer 120 is wound on the insulating layer 101 with the central through-hole 101a as a reference, and a secondary winding 121 is formed as the signal wiring 100 that constitutes the second coil 32 in the above-mentioned transformer T. The secondary winding 121 of this embodiment has one turn and a line width corresponding to one turn, and is wound so as to include a space between the central through-hole 101a and the outer edge through-hole 101b.

[0022] In addition, in the second component layer 120, a third outgoing wiring 122 is formed as the signal wiring 100, which is drawn from one end of the secondary winding 121 and constitutes the third connection line 43. In the second component layer 120, a fifth outgoing wiring 123 is formed as the signal wiring 100, which is drawn from the other end of the secondary winding 121 and constitutes the fifth connection line 45. A fastening hole 123a is formed in the fifth outgoing wiring 123, through which a fastening member 60 described later is inserted. The fastening hole 123a is formed so as to penetrate the fifth outgoing wiring 123 and the insulating layer 101. In this embodiment, the third outgoing wiring 122 corresponds to the first end portion outgoing wiring, and the fifth outgoing wiring 123 corresponds to the second end portion outgoing wiring. In the second component layer 120, a fourth connection line wiring 124 is formed, which is connected through a connection via 102 to a fourth escape wiring 132 formed in a third component layer 130 described later.

[0023] In this embodiment, the third escape wiring 122 and the fifth escape wiring 123 are formed on the same side as the third connection line wiring 113 and the fourth connection line wiring 114 in the first component layer 110. In other words, the third escape wiring 122 and the fifth escape wiring 123 are formed on a portion of the second component layer 120 that faces the first escape wiring 112 in the first component layer 110 and is located on the opposite side of the central through hole 101a.

[0024] The third component layer 130 is wound on the insulating layer 101 with the central through-hole 101a as a reference, and a tertiary winding 131 is formed as the signal wiring 100 that constitutes the third coil 33 in the above-mentioned transformer T. The tertiary winding 131 of this embodiment has one turn and a line width corresponding to one turn, and is wound so as to include a space between the central through-hole 101a and the outer edge through-hole 101b.

[0025] In addition, in the third component layer 130, a fourth outgoing wiring 132 is formed as the signal wiring 100, which is drawn from one end of the tertiary winding 131 and constitutes the fourth connection line 44. In the third component layer 130, a fifth outgoing wiring 133 is formed as the signal wiring 100, which is drawn from the other end of the tertiary winding 131 and constitutes the fifth connection line 45. In the fifth outgoing wiring 133, a fastening hole 133a is formed through which a fastening member 60 described later is inserted. The fastening hole 133a is formed so as to penetrate the fifth outgoing wiring 133 and the insulating layer 101. In this embodiment, the fourth outgoing wiring 132 corresponds to the first end portion outgoing wiring, and the fifth outgoing wiring 133 corresponds to the second end portion outgoing wiring. In the third component layer 130, a third connection line wiring 134 is formed, which is connected through a connection via 102 to a third connection line wiring 143 included in a fourth component layer 140 described later.

[0026] In this embodiment, the fourth escape wiring 132 and the fifth escape wiring 133 are formed on the same side as the third connection line wiring 113 and the fourth connection line wiring 114 in the first component layer 110. In other words, the fourth escape wiring 132 and the fifth escape wiring 133 are formed on a portion of the third component layer 120 that faces the first escape wiring 112 in the first component layer 110 and is located on the opposite side of the central through hole 101a.

[0027] As described above, the fourth component layer 140 is disposed on the opposite side of the insulating layer 101 of the third component layer 130 from the side on which the tertiary winding 131 and the like are formed. The fourth component layer 140 has a lower primary winding 141 as the signal wiring 100 wound around the central through hole 101a formed in the insulating layer 101 of the third component layer 130. The lower primary winding 141 of this embodiment has four turns and a line width that allows four turns, and is wound around to include a space between the central through hole 101a and the outer edge through hole 101b formed in the third component layer 130. The other end of the lower primary winding 141 on the central through hole 101a side is electrically connected to the other end of the upper primary winding 111 on the central through hole 101a side through the connection vias 102 formed in the first to third component layers 110, 120, and 130. For this reason, the first coil 31 in this embodiment is composed of an upper primary winding 111 and a lower primary winding 141.

[0028] The fourth component layer 140 also has, as the signal wiring 100, a second lead-out wiring 142 that is led out from one end of the lower primary winding 141 opposite the central through-hole 101a and constitutes the second connection line 42. The fourth component layer 140 also has, as the signal wiring 100, a third connection line wiring 143 that is connected to the third connection line wiring 134 of the third component layer 130 via the connection via 102, and a fourth connection line wiring 144 that is connected to the fourth lead-out wiring 132 via the connection via 102.

[0029] The second escape wiring 142 is formed on the same side as the first escape wiring 112 in the first component layer 110. The third connection line wiring 143 and the fourth connection line wiring 144 are formed on the opposite side of the central through hole 101a to the side on which the second escape wiring 142 is formed.

[0030] In this embodiment, as described above, the first coil 31 is formed by the primary windings 111 and 141 formed on the first and fourth constituent layers 110 and 140. The second coil 32 is formed by the secondary winding 121 formed on the second constituent layer 120. The third coil 33 is formed by the tertiary winding 131 formed on the third constituent layer 130. The first connection line 41 is formed by the first escape wiring 112 formed on the first constituent layer 110. The second connection line 42 is formed by the second escape wiring 142 formed on the fourth constituent layer 140. The third connection line 43 is formed by the third escape wiring 122 formed on the second constituent layer 120, and the fifth connection line 45 is formed by the fifth escape wiring 123. The fourth connection line 44 is formed by the fourth escape wiring 132 formed on the third constituent layer 130, and the fifth connection line 45 is formed by the fifth escape wiring 133.

[0031] Moreover, the first to fourth constituent layers 140 have heat dissipation wiring 150. Specifically, the first constituent layer 110 has the heat dissipation wiring 150 arranged around the upper primary winding 111 on the insulating layer 101 and thermally connected to the upper primary winding 111. The second constituent layer 120 has the heat dissipation wiring 150 around the secondary winding 121 and thermally connected to the secondary winding 121. The third constituent layer 130 has the heat dissipation wiring 150 around the tertiary winding 131 and thermally connected to the tertiary winding 131. The fourth constituent layer 140 has the heat dissipation wiring 150 around the lower primary winding 141 and thermally connected to the lower primary winding 141. That is, the first to fourth constituent layers 140 each have the heat dissipation wiring 150 on the same plane as each of the windings 111, 121, 131, and 141. The heat dissipation wiring 150 is made of copper or the like, similarly to the signal wiring 100, for example.

[0032] Each heat dissipation wiring 150 is formed with a fastening hole 151 for inserting a fastening member 60 described later. Specifically, each heat dissipation wiring 150 is divided as described later, and a fastening hole 151 is formed in each divided region. The fastening hole 151 is formed so as to penetrate the heat dissipation wiring 150 and the insulating layer 101. The fastening holes 151 in each heat dissipation wiring 150 of the first to fourth constituent layers 110, 120, 130, and 140 are formed at the same position in the normal direction to one surface 1a of the printed circuit board 1. Each heat dissipation wiring 150 formed in the first to fourth constituent layers 110, 120, 130, and 140 is divided as described later, but is thermally connected to each other via a connection via 102. That is, each heat dissipation wiring 150 formed in the second to fourth constituent layers 120, 130, and 140 is thermally connected to the heat dissipation wiring 150 formed in the first constituent layer 110. In other words, each of the heat dissipation wirings 150 formed in the first to third constituent layers 110 to 130 is thermally connected to the heat dissipation wiring 150 formed in the fourth constituent layer 140.

[0033] The core 20 provided on the printed circuit board 1 is made of a magnetic material such as ferrite, and is configured by combining a pair of a first core 21 and a second core 22. In this embodiment, the first core 21 and the second core 22 are configured to have bases 21a, 22a, and inner legs 21b, 22b and a pair of outer legs 21c, 22c extending from the bases 21a, 22a.

[0034] Each of the bases 21a, 22a is a flat plate with one direction as the longitudinal direction. The inner legs 21b, 22b are formed at the center of the bases 21a, 22a in the longitudinal direction, protruding in the normal direction to the surface direction of the bases 21a, 22a. The pair of outer legs 21c, 22c are formed at both ends of the bases 21a, 22a in the longitudinal direction, protruding in the normal direction to the surface direction of the bases 21a, 22a. In other words, the first core 21 and the second core 22 of this embodiment are each a so-called E-shaped core.

[0035] The first core 21 is arranged such that the inner leg 21b is inserted into the central through hole 101a from the one surface 1a side of the printed circuit board 1, and the outer leg 21c is inserted into each of the outer edge through holes 101b. The second core 22 is arranged such that the inner leg 22b is inserted into the central through hole 101a from the other surface 1b side of the printed circuit board 1, and the outer leg 22c is inserted into each of the outer edge through holes 101b. That is, the first core 21 and the second core 22 are arranged facing each other. This forms a closed magnetic circuit in the transformer construction area 10. The protruding heights of the inner leg 21b, 22b and the outer leg 21c, 22c of the first core 21 and the second core 22 are adjusted so that the inner leg 21b, 22b and the outer leg 21c, 22c of each core abut against each other when the first core 21 and the second core 22 are arranged on the printed circuit board 1.

[0036] In this embodiment, a heat dissipation member 50 made of an insulating material with high thermal conductivity is disposed between the core 20 and the printed circuit board 1. Such a heat dissipation member 50 is made of heat dissipation grease, heat dissipation gaffier, heat dissipation putty sheet, heat dissipation gel sheet, or the like.

[0037] Here, the heat dissipation wiring 150 of this embodiment is formed in each of the windings 111, 121, 131, and 141, and is divided at the portions where the lead-out wirings 112, 122, 123, 132, 133, 142, etc. are formed. In addition, the heat dissipation wiring 150 of this embodiment is further divided into a plurality of regions in the normal direction to the surface direction of the printed circuit board 1. Specifically, as shown in FIG. 4A, the heat dissipation wiring 150 of the first component layer 110 is divided into a region located on one side of the core 20 and a region located on the other side of the core 20, based on a virtual line K that passes through the upper primary winding 111 and extends along one direction in the surface direction of the printed circuit board 1. In other words, the heat dissipation wiring 150 is divided around the upper primary winding 111 so as not to form a winding, and is arranged so as not to function as a coil. In this embodiment, the heat dissipation wiring 150 is divided at the portion overlapping the core 20 into a region located on one side of the core 20 and a region located on the other side of the core 20 .

[0038] Similarly, the heat dissipation wiring 150 of the second and third constituent layers 120 and 130 is divided in the same manner as the heat dissipation wiring 150 of the first constituent layer 110. That is, the heat dissipation wiring 150 of the second and third constituent layers 120 and 130 is divided into an area located on one side of the core 20 and an area located on the other side of the core 20 with respect to a virtual line K extending along one direction in the surface direction of the printed circuit board 1 as shown in FIG. 4B or 4C. Also, the heat dissipation wiring 150 of the fourth constituent layer 140 is divided into an area located on one side of the core 20 and an area located on the other side of the core 20 with respect to a virtual line extending along one direction in the surface direction of the printed circuit board 1 as shown in FIG. 3, although details are not shown.

[0039] The housing 2 is made of a conductive material and has a predetermined shape. The printed circuit board 1 is fixed to the housing 2 via fastening members 60 such as screws so that the other surface 1b faces the housing 2. The housing 2 of this embodiment also dissipates heat from the printed circuit board 1, and functions as a heat sink.

[0040] The printed circuit board 1 is fixed to the housing 2 at a predetermined location on the outer edge via a fastening member 60. The printed circuit board 1 is also fixed to the housing 2 in the transformer forming region 10 via a fastening member 60 arranged by inserting through a fastening hole 123a formed in the fifth outgoing wiring 123 of the second component layer 120 and a fastening hole 133a formed in the fifth outgoing wiring 133 of the third component layer 130. As a result, the fifth outgoing wirings 123 and 133 are thermally and electrically connected to the housing 2. The printed circuit board 1 is also fixed to the housing 2 in the transformer forming region 10 via a fastening member 60 arranged by inserting through a fastening hole 151 formed in the heat dissipation wiring 150. As a result, the heat dissipation wiring 150 formed in the first component layer 110 is thermally connected to the housing 2 via the fastening member 60. Moreover, each of the heat dissipation wirings 150 formed on the second to fourth constituent layers 120, 130, and 140 is thermally connected to the heat dissipation wiring 150 formed on the first constituent layer 110, and is therefore thermally connected to the housing 2 via the heat dissipation wiring 150 formed on the first constituent layer 110 and the fastening member 60. That is, all of the heat dissipation wirings 150 formed on the first to fourth constituent layers 110, 120, 130, and 140 are thermally connected to the housing 2 via the fastening member 60. Moreover, the fourth constituent layer 140 is disposed so that the heat dissipation wiring 150 of the fourth constituent layer 140 is in direct contact with the housing 2, as shown in FIG. 5B in particular. And each of the heat dissipation wirings 150 formed on the first to third constituent layers 110, 120, and 130 is thermally connected to the heat dissipation wiring 150 formed on the fourth constituent layer 110. Therefore, the heat dissipation wiring 150 formed on the first to third component layers 110, 120, and 130 is thermally connected to the housing 2 via the heat dissipation wiring 150 formed on the fourth component layer 140.

[0041] As described above, the heat dissipation wiring 150 is divided into a plurality of regions. The heat dissipation wiring 150 is also divided according to the shape of the signal wiring 100 in each of the component layers 110, 120, 130, and 140. However, the heat dissipation wiring 150 in each of the component layers 110, 120, 130, and 140 is appropriately connected through the connection vias 102. The locations of the fastening members 60 and the locations of the connection vias 102 that connect the heat dissipation wiring 150 in each of the component layers 110, 120, 130, and 140 are adjusted so that all the heat dissipation wiring 150 are thermally connected to the housing 2.

[0042] The housing 2 of this embodiment is provided with a metal holder 70, one end of which is fixed so that the other end is located on the printed circuit board 1. The core 20 arranged on the printed circuit board 1 is arranged so as to be pressed by one end of the holder 70.

[0043] According to the present embodiment described above, in the printed circuit board 1, the heat dissipation wiring 150 is arranged on the same plane as the windings 111, 121, 131, and 141. This makes it easier to arrange the heat dissipation wiring 150 in close proximity to the windings 111, 121, 131, and 141, thereby improving heat dissipation.

[0044] (1) In this embodiment, the transformer T is configured using a printed circuit board 1 as a multilayer board. Therefore, it is possible to achieve a smaller size compared to a case where members corresponding to the signal wiring 100, the insulating layer 101, the heat dissipation wiring 150, etc. in this embodiment are prepared separately and stacked.

[0045] (2) In this embodiment, the heat dissipation member 50 is disposed between the printed circuit board 1 and the core 20. Therefore, heat from the printed circuit board 1 can be dissipated from the core 20 via the heat dissipation member 50. In particular, in this embodiment, the core 20 is pressed against the holder 70. Therefore, heat can also be dissipated from the printed circuit board 1 to the housing 2 via the core 20 and the holder 70.

[0046] (3) In this embodiment, the heat dissipation wiring 150 is divided into an area located on one side of the core 20 and an area located on the other side of the core 20, with respect to a virtual line K extending in one direction in the surface direction of the printed circuit board 1. That is, the heat dissipation wiring 150 is arranged so as not to function as a coil. Therefore, compared with the case where the heat dissipation wiring 150 is not divided in this manner, the loss of the transformer T can be reduced. That is, when the heat dissipation wiring 150 is not divided, the heat dissipation wiring 150 is formed around the windings 111, 121, 131, and 141, and there is a possibility that the heat dissipation wiring 150 functions as a coil. In this case, as shown in FIG. 6, the heat dissipation wiring 150 functions as a coil, and a short-circuit current flows through the heat dissipation wiring 150, causing a loss in the transformer T. In contrast, the heat dissipation wiring 150 of this embodiment is arranged so as not to function as a coil. Therefore, it is possible to suppress the occurrence of a loss in the transformer T caused by a short-circuit current flowing through the heat dissipation wiring 150.

[0047] (Modification of the first embodiment) A modified example of the first embodiment will be described. In the first embodiment, the configuration of the transformer configuration region 10 can be appropriately changed. For example, as shown in FIG. 7, the transformer configuration region 10 may be configured by stacking a first configuration layer 110 in which a primary winding 111 is formed and a second configuration layer 120 in which a secondary winding 121 is formed. Note that FIG. 7 shows an example in which the primary winding 111 and the secondary winding 121 are each a single turn. Although not shown in particular, the second coil 32 may be configured by connecting windings formed in different configuration layers, similar to the first coil 31. Similarly, the third coil 33 may be configured by connecting windings formed in different configuration layers, similar to the first coil 31.

[0048] Second embodiment The second embodiment will be described. In this embodiment, the configurations of the second component layer 120 and the third component layer 130 are changed from those of the first embodiment. As the rest is the same as the first embodiment, the description will be omitted here.

[0049] In the power conversion device of the present embodiment, as shown in Fig. 8A, the second component layer 120 is configured such that the fifth escape wiring 123 and the heat dissipation wiring 150 are connected to each other. Also, as shown in Fig. 8B, the third component layer 130 is configured such that the fifth escape wiring 133 and the heat dissipation wiring 150 are connected to each other. That is, a part of the heat dissipation wiring 150 of the present embodiment also functions as the signal wiring 100.

[0050] According to the present embodiment described above, since the heat dissipation wiring 150 is arranged on the same plane as the windings 111, 121, 131, and 141, it is possible to obtain the same effects as in the first embodiment.

[0051] (1) In this embodiment, the fifth escape wiring 123 and the heat dissipation wiring 150 are connected in the second component layer 120. The fifth escape wiring 133 and the heat dissipation wiring 150 are connected in the third component layer 130. Therefore, compared to the above-described first embodiment, the areas of the fifth escape wiring 123, 133 in the second and third component layers 120, 130 are increased. Therefore, the wiring resistance of the fifth escape wiring 123, 133 can be reduced, and heat generation in the fifth escape wiring 123, 133 can be suppressed.

[0052] (Modification of the second embodiment) A modification of the second embodiment will be described below. In the second embodiment, only one of the fifth escape wiring 123 of the second component layer 120 and the fifth escape wiring 133 of the third component layer 130 may be connected to the heat dissipation wiring 150.

[0053] Third embodiment A third embodiment will be described. This embodiment is different from the second embodiment in that the configurations of the second component layer 120 and the third component layer 130 are changed. As the rest is the same as the second embodiment, a description thereof will be omitted here.

[0054] 9A, in the power conversion device of the present embodiment, in the second component layer 120, a connection region R1 between the secondary winding 121 and the fifth escape wiring 123 is larger than a connection region R2 between the secondary winding 121 and the third escape wiring 122. Also, in the third component layer 130, a connection region R3 between the tertiary winding 131 and the fifth escape wiring 133 is larger than a connection region R4 between the tertiary winding 131 and the fourth escape wiring 132, as shown in FIG.

[0055] According to the present embodiment described above, since the heat dissipation wiring 150 is arranged on the same plane as the windings 111, 121, 131, and 141, it is possible to obtain the same effects as in the first embodiment.

[0056] (1) In this embodiment, a connection area R1 between the secondary winding 121 and the fifth escape wiring 123 is larger than a connection area R2 between the secondary winding 121 and the third escape wiring 122. For this reason, compared to a case in which the connection area R1 between the secondary winding 121 and the fifth escape wiring 123 is equal to the connection area R2 between the secondary winding 121 and the third escape wiring 122, the wiring resistance of the fifth escape wiring 123 can be further reduced and heat generation in the fifth escape wiring 123 can be suppressed.

[0057] Similarly, a connection area R3 between the tertiary winding 131 and the fifth escape wiring 133 is larger than a connection area R4 between the tertiary winding 131 and the fourth escape wiring 132. Therefore, compared to a case in which the connection area R3 between the tertiary winding 131 and the fifth escape wiring 133 is equal to the connection area R4 between the tertiary winding 131 and the fourth escape wiring 132, the wiring resistance of the fifth escape wiring 133 can be further reduced, and heat generation in the fifth escape wiring 133 can be suppressed.

[0058] (Modification of the third embodiment) A modification of the third embodiment will now be described. In the third embodiment, the size of the connection region in only one of the second component layer 120 and the third component layer 130 may be different.

[0059] (Fourth embodiment) A fourth embodiment will be described. In this embodiment, a one-surface heat dissipation member and an other-surface heat dissipation member are arranged in comparison with the first embodiment. As the rest is the same as the first embodiment, a description thereof will be omitted here.

[0060] In the power conversion device of this embodiment, as shown in Figures 10 to 12, in the transformer construction area 10 of the printed circuit board 1, a one-side heat dissipation member 81 is arranged on one surface 1a, and an other-side heat dissipation member 82 is arranged on the other surface 1b.

[0061] The one-side heat dissipation member 81 and the other-side heat dissipation member 82 have a predetermined thickness and thermal conductivity, and are made of heat dissipation grease, heat dissipation gaffier, heat dissipation putty sheet, heat dissipation gel sheet, or the like made of insulating material. Note that in FIG. 11, the one-side heat dissipation member 81 and the other-side heat dissipation member 82 are illustrated as sheet-shaped members. The one-side heat dissipation member 81 and the other-side heat dissipation member 82 are formed with insertion holes 81a, 82a through which the fastening member 60 is inserted. The one-side heat dissipation member 81 is formed with a recessed portion 81b corresponding to the signal wiring 100 in the first component layer 110. The other-side heat dissipation member 82 is formed with a recessed portion 82b corresponding to the signal wiring 100 in the fourth component layer 140. Note that in FIG. 11, the recessed portion 82b formed in the other-side heat dissipation member 82 is omitted.

[0062] A pressing member 90 is disposed on one surface 1a of the printed circuit board 1 via a one-surface heat dissipation member 81. In this embodiment, two pressing members 90 are disposed so as to sandwich the core 20 and press both sides of the one-surface heat dissipation member 81 exposed from the core 20 in the normal direction to the surface direction of the printed circuit board 1. An insertion hole 90a through which the fastening member 60 is inserted is formed in the pressing member 90. The pressing member 90 in this embodiment is made of copper or the like.

[0063] The printed circuit board 1 is disposed in the housing 2 such that the other-side heat dissipation member 82 is located between the other side 1b and the housing 2 and is in contact with the housing 2. The printed circuit board 1 is fixed to the housing 2 via the fastening member 60 in a state in which the one-side heat dissipation member 81 and the pressing member 90 are disposed on the one side 1a and the fastening member 60 is thermally connected to the pressing member 90.

[0064] According to the present embodiment described above, since the heat dissipation wiring 150 is arranged on the same plane as the windings 111, 121, 131, and 141, it is possible to obtain the same effects as in the first embodiment.

[0065] (1) In this embodiment, another-side heat dissipation member 82 is disposed between the housing 2 and the printed circuit board 1. As a result, heat can be dissipated from the windings 111, 121, 131, 141 that constitute the first to third coils 31 to 33 to the housing 2 via the another-side heat dissipation member 82, thereby further improving heat dissipation.

[0066] (2) In this embodiment, one-surface heat dissipation member 81 is disposed on one surface 1a of printed circuit board 1. For this reason, heat from windings 111, 121, 131, 141 constituting first to third coils 31 to 33 is also transferred to pressing member 90 via one-surface heat dissipation member 81, and pressing member 90 is thermally connected to fastening member 60, thereby further improving heat dissipation to housing 2.

[0067] Fifth embodiment A fifth embodiment will be described. In this embodiment, the pressing member 90 and the holder 70 are integrated together, as opposed to the fourth embodiment. As the rest of the configuration is the same as the fourth embodiment, a description thereof will be omitted here.

[0068] In the power converter of this embodiment, as shown in FIG. 13, the pressing member 90 has two support parts 90b located on one surface 1a of the printed circuit board 1 and fastened by the fastening member 60, and one pressing part 90c located on the core 20. The shape of the pressing part 90c is adjusted so that it can press the core 20. The pressing member 90 of this embodiment is configured so that the two support parts 90b are connected by one pressing part 90c. In other words, the pressing member 90 of this embodiment is configured from one member. Moreover, the power converter of this embodiment does not include the holder 70 described in the first embodiment.

[0069] According to the present embodiment described above, since the heat dissipation wiring 150 is arranged on the same plane as the windings 111, 121, 131, and 141, it is possible to obtain the same effects as in the first embodiment.

[0070] (1) According to this embodiment, since the core 20 is pressed by the pressing member 90, there is no need to provide the holder 70. Therefore, compared to the above-described fourth embodiment, the number of parts can be reduced. In addition, since the core 20 is pressed by the pressing member 90, heat from the core 20 can be dissipated to the housing 2 via the pressing member 90 and the fastening member 60.

[0071] (Modification of the fifth embodiment) A modified example of the fifth embodiment will be described. In the fifth embodiment, as shown in FIG. 14, the pressing member 90 may be provided with a pressing portion 90c on each of the two support portions 90b. In other words, compared to the fifth embodiment, the pressing member 90 may be separated into a pressing portion 90c provided on one support portion 90b and a pressing portion 90c provided on the other support portion 90b at a predetermined location on the core 20, and may be composed of two members. According to this, compared to the fourth embodiment, it becomes easier to adjust the pressing force of the pressing portion 20b against the core 20, and the manufacturing process can be simplified.

[0072] Sixth embodiment A sixth embodiment will be described. In this embodiment, the configuration of the portion of the printed circuit board 1 where the fastening member 60 is arranged is adjusted in comparison with the first embodiment. As the rest is similar to the first embodiment, the description will be omitted here.

[0073] First, in the first embodiment, the outer edge of the printed circuit board 1 is fixed to the housing 2 via the fastening member 60, and the transformer configuration area 10 is fixed to the housing 2 via the fastening member 60. That is, the printed circuit board 1 is fixed to the housing 2 at a plurality of points via the fastening member 60. In this case, as shown in FIG. 15, if the total thickness of the wiring 200 in the portion where the fastening member 60 is arranged is different, the printed circuit board 1 cannot be uniformly fastened to the housing 2, and the printed circuit board 1 may be tilted relative to the surface direction of the housing 2. If the printed circuit board 1 is tilted relative to the surface direction of the housing 2, the heat dissipation from the printed circuit board 1 to the housing 2 may be reduced. In this embodiment, the wiring 200 is a general term for various wirings including the signal wiring 100 and the heat dissipation wiring 150.

[0074] For this reason, in this embodiment, as shown in Fig. 16, the total thickness of the wiring 200 in the portion where the fastening member 60 is arranged is set to be the same. As a result, in this embodiment, the printed circuit board 1 can be uniformly fastened to the housing 2, and the printed circuit board 1 can be prevented from tilting with respect to the surface direction of the housing 2. Note that the wiring 200 in the portion where the fastening member 60 is arranged may be only the signal wiring 100, only the heat dissipation wiring 150, or a combination of the signal wiring 100 and the heat dissipation wiring 150. Furthermore, the wiring 200 may be a dummy wiring for ensuring a certain thickness, and its use is not particularly limited.

[0075] According to the present embodiment described above, since the heat dissipation wiring 150 is arranged on the same plane as the windings 111, 121, 131, and 141, it is possible to obtain the same effects as in the first embodiment.

[0076] (1) In this embodiment, the total thickness of the wiring 200 in the portion where the fastening member 60 is arranged is the same. This allows the printed circuit board 1 to be uniformly fastened to the housing 2, and prevents the printed circuit board 1 from tilting relative to the surface direction of the housing 2. This prevents a decrease in the heat dissipation from the printed circuit board 1 to the housing 2.

[0077] (Modification of the sixth embodiment) A modified example of the sixth embodiment will be described. In the sixth embodiment, as long as the thicknesses of the wirings 200 in the portions where the fastening members 60 are arranged are the same, the wirings 200 may be formed in different layers as shown in Fig. 17. That is, as long as the total thicknesses of the wirings 200 in the portions where the fastening members 60 are arranged are the same, the layer in which the wirings 200 are formed can be changed as appropriate.

[0078] Seventh embodiment A seventh embodiment will be described. This embodiment is different from the first embodiment in that the configuration of the first component layer 110 is changed. As the rest is similar to the first embodiment, a description thereof will be omitted here.

[0079] In the power conversion device of this embodiment, as shown in Fig. 18, a portion of the heat dissipation wiring 150 in the first component layer 110 is drawn out to the outside of the transformer assembly region 10. In Fig. 18, the heat dissipation wiring 150 in the upper right corner of the page is drawn out to the outside of the transformer assembly region 10. This heat dissipation wiring 150 is used as a ground wiring for other electronic components and the like arranged on the printed circuit board 1. In other words, this heat dissipation wiring 150 is connected to the signal wiring 100 outside the transformer assembly region 10.

[0080] According to the present embodiment described above, since the heat dissipation wiring 150 is arranged on the same plane as the windings 111, 121, 131, and 141, it is possible to obtain the same effects as in the first embodiment.

[0081] (1) In this embodiment, the heat dissipation wiring 150 connected to the housing 2 is connected to the signal wiring 100 outside the transformer assembly area 10. In other words, the heat dissipation wiring 150 connected to the housing 2 is used to maintain the signal wiring 100 outside the transformer assembly area 10 at ground potential. This allows the heat dissipation wiring 150 to be used more effectively.

[0082] (Modification of the seventh embodiment) A modification of the seventh embodiment will be described below. In the seventh embodiment, the heat dissipation wiring 150 in the second to fourth component layers 120, 130, and 140 may be connected to the signal wiring 100 outside the transformer component region .

[0083] Eighth embodiment An eighth embodiment will be described. This embodiment is different from the first embodiment in that the configuration of the transformer forming region 10 is changed. As the rest is similar to the first embodiment, a description thereof will be omitted here.

[0084] In the power converter of this embodiment, as shown in Fig. 19, the transformer construction region 10 has a construction layer 160 in which a signal wiring 100 functioning as a coil wiring is formed on an insulating layer 101. Specifically, the construction layer 160 of this embodiment has a rectangular shape with one direction as the longitudinal direction. The signal wiring 100 passes through approximately the center of the construction layer 160 and is formed linearly along the longitudinal direction.

[0085] Furthermore, two through holes 101c are formed in the insulating layer 101 so as to sandwich the signal wiring 100. The through holes 101c are formed at positions and with sizes such that the legs 21c, 22c of the first core 21 or the second core 22 can be inserted therein.

[0086] The first core 21 and the second core 22 of this embodiment are configured to have bases 21a, 22a and a pair of outer legs 21c, 22c extending from the bases 21a, 22a. The bases 21a, 22a are flat plates with one direction as the longitudinal direction. The pair of outer legs 21c, 22c are formed to protrude in the normal direction to the surface direction of the bases 21a, 22a at both ends in the short direction perpendicular to the longitudinal direction of the bases 21a, 22a. In other words, the first core 21 and the second core 22 of this embodiment are each a so-called U-shaped core.

[0087] The first and second cores 21, 22 are arranged facing each other with their outer legs 21c, 22c inserted into the through holes 101c, respectively. That is, the power conversion device of this embodiment is configured to have a choke coil.

[0088] Moreover, on the insulating layer 101, a heat dissipation wiring 150 that is thermally connected to the signal wiring 100 is formed around the signal wiring 100. A fastening hole 151 is formed in the heat dissipation wiring 150 in a portion exposed from the core 20. Although not particularly shown, the heat dissipation wiring 150 is fixed to the housing 2 via a fastening member 60.

[0089] According to the present embodiment described above, since the heat dissipation wiring 150 and the signal wiring 100 are arranged on the same plane, it is possible to obtain the same effects as those of the first embodiment.

[0090] (Other embodiments) Although the present disclosure has been described based on the embodiment, it is understood that the present disclosure is not limited to the embodiment or structure. The present disclosure also encompasses various modifications and modifications within the equivalent range. In addition, various combinations and forms, as well as other combinations and forms including only one element, more than one element, or less than one element, are also within the scope and concept of the present disclosure.

[0091] For example, in each of the above embodiments, it is possible to appropriately change the number of constituent layers constituting the printed circuit board 1. In this case, the transformer construction region 10 may be formed to include a constituent layer in which no winding is formed.

[0092] In each of the above embodiments, the heat dissipation member 50 does not necessarily have to be disposed between the core 20 and the printed circuit board 1.

[0093] In the first to seventh embodiments, the transformer T may not have the second coil 32 and the third coil 33 connected in series as shown in FIG. 20. That is, the sixth connection wire 46 may be connected to the end of the second coil 32 opposite to the third connection wire 43, and the seventh connection wire 47 may be connected to the end of the third coil 33 opposite to the fourth connection wire 44. In this case, the fifth outgoing wiring 123 in the second component layer 120 constitutes the sixth connection wire 46, and the fifth outgoing wiring 133 in the third component layer 130 constitutes the seventh connection wire 47. Although not particularly shown, the location where the fastening member 60 is disposed is changed so that the fifth outgoing wiring 123 in the second component layer 120 and the fifth outgoing wiring 133 in the second component layer 130 are not electrically connected to each other, thereby forming the transformer T in FIG. 20.

[0094] Furthermore, in the first to seventh embodiments, the heat dissipation wiring 150 may be divided in the normal direction not at a portion overlapping the core 20 but at a portion exposed from the core 20. The heat dissipation wiring 150 may be further divided by a plurality of imaginary lines K. In other words, as long as the heat dissipation wiring 150 does not function as a coil, the position at which it is divided and the manner of division can be changed as appropriate.

[0095] In each of the above embodiments, the electronic device may not include the core 20. Even in such an electronic device, the heat dissipation performance can be improved by arranging the heat dissipation wiring 150, which is thermally connected to the signal wiring 100, on the same plane as the signal wiring 100.

[0096] In the fourth embodiment, the electronic device may be configured to include only one of the one-side heat dissipation member 81 and the other-side heat dissipation member 82. When only the other-side heat dissipation member 82 is included, the pressing member 90 does not need to be disposed.

[0097] The above-mentioned embodiments may be appropriately combined. For example, the above-mentioned fourth embodiment may be combined with each embodiment to provide a one-side heat dissipation member 81 and an other-side heat dissipation member 82. In this case, as in the above-mentioned fifth embodiment, the pressing member 90 may be provided with a pressing portion 90c. The above-mentioned sixth embodiment may be combined with each embodiment to provide the same total thickness of the wiring 200 in the portion where the fastening member 60 is arranged. The above-mentioned seventh embodiment may be combined with each embodiment to connect the heat dissipation wiring 150 to the signal wiring 100 outside the transformer configuration region 10. [Explanation of symbols]

[0098] 1 Printed circuit board 1a one side 1b Other side 100 Signal Wiring 150 Heat dissipation wiring

Claims

1. An electronic device having a signal wiring (100), The substrate (1) has one surface (1a) and another surface (1b) opposite to the one surface, and the signal wiring is formed on an insulating layer (101); The substrate has a heat dissipation wiring (150) formed on the insulating layer and on the same plane as the signal wiring, the heat dissipation wiring being thermally connected to the signal wiring; The substrate has through holes (101a, 101b) formed therethrough in the thickness direction, A core (20) that forms a closed magnetic circuit is disposed at a position including the through hole, The substrate is a multilayer substrate in which a plurality of constituent layers (110, 120, 130, 140) are laminated, The signal wiring includes a winding (111, 121, 131, 141) wound around the through hole in two or more of the component layers, and a lead-out wiring (112, 122, 123, 132, 133, 142) connected to the winding, the winding has portions located on both sides of the core in a surface direction of the substrate, the heat dissipation wiring is formed in a location including the periphery of the winding located on both sides of the core in the surface direction, and is divided into an area located on one side of the core and an area located on the other side of the core based on a virtual line (K) that passes through the winding and extends along one direction in the surface direction of the substrate, the heat dissipation wiring is divided into a region located on one side of the core and a region located on the other side of the core at a portion overlapping the core in a normal direction to a surface direction of the substrate, In at least one of the two or more component layers, one end of the winding is connected to a first end lead (122, 132) and the other end is connected to a second end lead (123, 133), The electronic device includes a second end portion lead wiring electrically connected to a housing (2) made of a conductive material via a fastening member (60) and connected to the heat dissipation wiring.

2. An electronic device having a signal wiring (100), The substrate (1) has one surface (1a) and another surface (1b) opposite to the one surface, and the signal wiring is formed on an insulating layer (101); The substrate has a heat dissipation wiring (150) formed on the insulating layer and on the same plane as the signal wiring, the heat dissipation wiring being thermally connected to the signal wiring; The substrate has through holes (101a, 101b) formed therethrough in the thickness direction, A core (20) that forms a closed magnetic circuit is disposed at a position including the through hole, The substrate is a multilayer substrate in which a plurality of constituent layers (110, 120, 130, 140) are laminated, The signal wiring includes a winding (111, 121, 131, 141) wound around the through hole in two or more of the component layers, and a lead-out wiring (112, 122, 123, 132, 133, 142) connected to the winding, In at least one of the two or more component layers, one end of the winding is connected to a first end lead (122, 132) and the other end is connected to a second end lead (123, 133), The electronic device includes a second end portion lead wiring electrically connected to a housing (2) made of a conductive material via a fastening member (60) and connected to the heat dissipation wiring.

3. the winding has portions located on both sides of the core in a surface direction of the substrate, 3. The electronic device of claim 2, wherein the heat dissipation wiring is formed in a location including the periphery of the windings located on both sides of the core in the planar direction, and is divided into an area located on one side of the core and an area located on the other side of the core based on a virtual line (K) that passes through the winding and extends along one direction in the planar direction of the substrate.

4. 4. The electronic device according to claim 1, wherein a connection area (R1, R3) between the winding and the second end lead wiring is larger than a connection area (R2, R4) between the winding and the first end lead wiring.

5. The substrate is disposed so as to face a housing (2) whose other surface is made of a conductive material; 5. The electronic device according to claim 1, further comprising a heat sink (81, 82) thermally connected to the signal wiring and disposed on at least one of the first and second surfaces of the substrate.

6. The heat dissipation member is disposed on one surface of the substrate, A pressing member (90) is disposed on the heat dissipation member, The substrate has through holes (101a, 101b) formed therethrough in the thickness direction, A core (20) that forms a closed magnetic circuit is disposed at a position including the through hole, 6. The electronic device according to claim 5, wherein the pressing member has a support portion (90b) arranged on the heat dissipation member, and a pressing portion (90c) integrated with the support portion for pressing the core.

7. 7. The electronic device according to claim 1, further comprising a heat dissipation member (50) disposed between the substrate and the core.

8. An electronic device having a signal wiring (100), The substrate (1) has one surface (1a) and another surface (1b) opposite to the one surface, and the signal wiring is formed on an insulating layer (101); The substrate has a heat dissipation wiring (150) formed on the insulating layer and on the same plane as the signal wiring, the heat dissipation wiring being thermally connected to the signal wiring; The substrate is disposed so as to face a housing (2) whose other surface is made of a conductive material; a heat dissipation member (81, 82) thermally connected to the signal wiring is disposed on at least one of the one surface and the other surface of the substrate; The heat dissipation member is disposed on one surface of the substrate, A pressing member (90) is disposed on the heat dissipation member, The substrate has through holes (101a, 101b) formed therethrough in the thickness direction, A core (20) that forms a closed magnetic circuit is disposed at a position including the through hole, The pressing member has a support portion (90b) arranged on the heat dissipation member, and a pressing portion (90c) integrated with the support portion for pressing the core.

9. 9. The electronic device according to claim 1, wherein the substrate is fixed to a housing (2) made of a conductive material via a fastening member (60) that is thermally connected to the heat dissipation wiring.

10. The substrate is fixed to the housing (2) at a plurality of points via fastening members (60), 10. The electronic device according to claim 1, wherein the portions of the substrate pressed by the fastening member have the same total thickness of wiring (200) including the signal wiring and the heat dissipation wiring.

11. The substrate has a transformer forming region (10) in which the signal wiring and the heat dissipation wiring are formed, 11. The electronic device according to claim 1, wherein the heat dissipation wiring is electrically connected to a housing (2) made of a conductive material and is connected to wiring outside the transformer configuration area.

Images