JP2013105853A

JP2013105853A - Wiring board

Info

Publication number: JP2013105853A
Application number: JP2011247920A
Authority: JP
Inventors: Ryoichi Shiraishi; 亮一白石
Original assignee: Denso Corp
Current assignee: Denso Corp
Priority date: 2011-11-11
Filing date: 2011-11-11
Publication date: 2013-05-30
Anticipated expiration: 2031-11-11
Also published as: JP5664527B2

Abstract

PROBLEM TO BE SOLVED: To provide a wiring board in which heat dissipation is improved while suppressing increase in physical size.SOLUTION: A wiring board includes a substrate composed of an insulating material, external wiring formed on an electronic-component mounting surface of the substrate, internal wiring formed in the substrate, and vias formed between the mounting surface of the substrate and the internal wiring. The external wiring has current wiring through which a current flows and heat-receiving wiring receiving heat generated in the current wiring. The vias has a heat-receiving via that electrically connects the heat receiving wiring to the internal wiring. The current wiring has a bifurcated shape, and the heat-receiving wiring is formed in the region surrounded by the bifurcated portion of the current wiring with a predetermined distance from the current wiring.

Description

本発明は、絶縁材料から成る基板と、該基板における電子部品の実装面に形成された外部配線と、基板の内部に形成された内部配線と、基板における実装面と内部配線との間に形成されたビアと、を有する配線基板に関するものである。 The present invention includes a substrate made of an insulating material, external wiring formed on the mounting surface of the electronic component on the substrate, internal wiring formed inside the substrate, and formed between the mounting surface and the internal wiring on the substrate. The present invention relates to a wiring board having vias.

従来、例えば特許文献１に示されるように、プリント配線基板の一面に電流回路が形成され、フロー半田付け工法を用いてリード端子付き電子部品がプリント配線基板の一面に半田接合された電子制御装置が提案されている。電流回路における電子部品のリード端子が半田付けされる部位は、銅箔を剥きだしとした銅箔ベタパターンとなっており、プリント基板には、銅箔ベタパターンと電気的に接続されるスルーホールが形成されている。そして、上記したスルーホールにジャンパーリード線が半田付けされ、このジャンパーリード線によって、電流回路の放熱性の向上が図られている。 Conventionally, as shown in Patent Document 1, for example, an electronic control device in which a current circuit is formed on one surface of a printed wiring board, and electronic components with lead terminals are soldered to one surface of the printed wiring board using a flow soldering method Has been proposed. The part where the lead terminal of the electronic component in the current circuit is soldered is a copper foil solid pattern with the copper foil stripped, and the printed circuit board has a through hole that is electrically connected to the copper foil solid pattern. Is formed. A jumper lead wire is soldered to the above-described through hole, and the heat dissipation of the current circuit is improved by the jumper lead wire.

特開２０１０−１６５８０８号公報JP 2010-165808 A

ところで、上記したように、特許文献１に示される電子制御装置では、電流回路の放熱性を向上するために、ジャンパーリード線を用いている。これによれば、電子制御装置における、プリント基板の厚さ方向の体格が増大する、という不具合が生じる虞がある。 By the way, as described above, the electronic control device disclosed in Patent Document 1 uses jumper lead wires to improve the heat dissipation of the current circuit. According to this, there exists a possibility that the malfunction that the physique of the thickness direction of a printed circuit board increases in an electronic controller may arise.

そこで、本発明は上記問題点に鑑み、体格の増大が抑制されつつ、放熱性が向上された配線基板を提供することを目的とする。 In view of the above problems, an object of the present invention is to provide a wiring board with improved heat dissipation while suppressing an increase in physique.

上記した目的を達成するために、請求項１に記載の発明は、絶縁材料から成る基板と、該基板における電子部品の実装面に形成された外部配線と、基板の内部に形成された内部配線と、基板における実装面と内部配線との間に形成されたビアと、を有する配線基板であって、外部配線は、電流の流れる電流配線と、該電流配線にて発生した熱を受熱する受熱配線と、を有し、ビアは、受熱配線と内部配線とを電気的に接続する受熱ビアを有しており、電流配線は、２本に分岐した形状を成し、受熱配線は、所定の間隔を空けて、電流配線における２本に分岐した部位にて囲まれた領域内に形成されていることを特徴とする。 In order to achieve the above-described object, the invention described in claim 1 includes a substrate made of an insulating material, external wiring formed on a mounting surface of an electronic component on the substrate, and internal wiring formed inside the substrate. And a via formed between the mounting surface of the substrate and the internal wiring, wherein the external wiring receives current wiring through which current flows and heat received by the current wiring Wiring, the via has a heat receiving via that electrically connects the heat receiving wiring and the internal wiring, the current wiring has a bifurcated shape, and the heat receiving wiring has a predetermined shape. It is characterized in that it is formed in a region surrounded by a bifurcated portion of the current wiring with an interval.

このように本発明によれば、電流配線にて生じた熱を受熱する受熱配線が、搭載面に形成されている。これによれば、搭載面にジャンパーリード線が接続される構成とは異なり、配線基板の厚さ方向の体格の増大が抑制されつつ、配線基板の放熱性が向上される。 Thus, according to the present invention, the heat receiving wiring that receives the heat generated in the current wiring is formed on the mounting surface. According to this, unlike the configuration in which the jumper lead wire is connected to the mounting surface, the increase in the physique in the thickness direction of the wiring board is suppressed, and the heat dissipation of the wiring board is improved.

また、本発明では、電流配線における２本に分岐した部位にて囲まれた領域内に、所定の間隔を空けて受熱配線が形成されている。これによれば、１本の電流配線と受熱配線とが所定の間隔を空けて隣接配置された構成と比べて、電流配線と受熱配線との対向面積が大きくなるので、電流配線にて生じた熱が、受熱配線に多く伝導される。これにより、放熱性が向上される。 In the present invention, the heat receiving wiring is formed at a predetermined interval in a region surrounded by the two branches of the current wiring. According to this, since the facing area between the current wiring and the heat receiving wiring is larger than the configuration in which one current wiring and the heat receiving wiring are arranged adjacent to each other at a predetermined interval, the current wiring is generated in the current wiring. A lot of heat is conducted to the heat receiving wiring. Thereby, heat dissipation is improved.

請求項２に記載のように、受熱配線の平面形状と、電流配線における２本に分岐した部位にて囲まれた領域の平面形状とは、相似であり、両者の間の対向間隔が一定である構成が好適である。 As described in claim 2, the planar shape of the heat receiving wiring is similar to the planar shape of the region surrounded by the two branches in the current wiring, and the facing distance between the two is constant. Certain configurations are preferred.

これによれば、受熱配線の平面形状と、電流配線における２本に分岐した部位にて囲まれた領域の平面形状とが相似でない構成、若しくは、両者が相似であるが、両者の間の対向間隔が不定である構成と比べて、電流配線と受熱配線との対向面積が大きくなる。そのため、電流配線にて生じた熱が、受熱配線に多く伝導され、放熱性が向上される。 According to this, the configuration in which the planar shape of the heat receiving wiring and the planar shape of the region surrounded by the two branches in the current wiring are not similar, or both are similar, but the two are facing each other Compared with the configuration in which the interval is indefinite, the facing area between the current wiring and the heat receiving wiring is increased. Therefore, much heat generated in the current wiring is conducted to the heat receiving wiring, and heat dissipation is improved.

請求項３に記載のように、受熱配線と電流配線との間に、絶縁性及び熱伝導性を有する熱伝導媒体が設けられ、受熱配線と電流配線とは、熱伝導媒体を介して熱的に接続された構成が好ましい。 According to a third aspect of the present invention, a heat conducting medium having insulation and thermal conductivity is provided between the heat receiving wiring and the current wiring, and the heat receiving wiring and the current wiring are thermally connected via the heat conducting medium. A configuration connected to is preferable.

これによれば、受熱配線と電流配線との間に熱伝導媒体が設けられていない構成と比べて、電流配線にて生じた熱が、受熱配線に多く伝導される。これにより、放熱性が向上される。 According to this, as compared with a configuration in which no heat conduction medium is provided between the heat receiving wiring and the current wiring, much heat generated in the current wiring is conducted to the heat receiving wiring. Thereby, heat dissipation is improved.

請求項４に記載のように、受熱配線は一方向に延びた形状を成し、その横幅が、受熱ビアとの接続部位よりも、該接続部位から延びた部位の方が短い構成が良い。 According to a fourth aspect of the present invention, it is preferable that the heat receiving wiring has a shape extending in one direction, and the lateral width of the portion extending from the connection portion is shorter than that of the connection portion with the heat receiving via.

これによれば、電流配線と受熱配線との対向面積、及び、搭載面の面積を変えずに、電流配線の形成面積を大きくすることができる。そのため、受熱配線が電流配線から受け取る熱量の低減、及び、配線基板の体格の増大が抑制されつつ、電流配線にて生じる熱量を少なくすることができる。 According to this, the formation area of the current wiring can be increased without changing the facing area between the current wiring and the heat receiving wiring and the area of the mounting surface. Therefore, the amount of heat generated in the current wiring can be reduced while the reduction in the amount of heat received by the heat receiving wiring from the current wiring and the increase in the size of the wiring board are suppressed.

請求項５に記載のように、受熱配線は、搭載面における、電流配線の２本に分岐した部位にて囲まれた領域以外の領域にも、電流配線と所定の間隔を空けて、形成された構成が良い。これによれば、請求項１に記載の構成と比べて、更に放熱性が向上される。 As described in claim 5, the heat receiving wiring is formed on the mounting surface in a region other than the region surrounded by the two branches of the current wiring with a predetermined distance from the current wiring. The configuration is good. According to this, compared with the structure of Claim 1, heat dissipation is further improved.

請求項６に記載のように、複数の受熱配線は、異なる内部配線に接続された構成が良い。内部配線に、受熱配線に伝達された熱を外部に放出するのに適した大きな配線（グランドと接続される配線や電源と接続される配線）が含まれている場合、その大きな配線の１つに、各受熱配線を接続すれば良い。しかしながら、内部配線に、上記した大きな配線がない場合、内部配線の発熱を抑えるため、各受熱配線を異なる内部配線に接続するのが望ましい。これに対して、請求項６に記載の構成では、各受熱配線が、異なる内部配線に接続されている。これによれば、各受熱配線に伝達された熱を、異なる内部配線に伝導することができる。 According to a sixth aspect of the present invention, the plurality of heat receiving wirings are preferably connected to different internal wirings. If the internal wiring includes a large wiring suitable for releasing the heat transferred to the heat receiving wiring to the outside (a wiring connected to the ground or a wiring connected to the power supply), one of the large wirings In addition, each heat receiving wiring may be connected. However, when the internal wiring does not have the large wiring described above, it is desirable to connect each heat receiving wiring to a different internal wiring in order to suppress the heat generation of the internal wiring. On the other hand, in the structure of Claim 6, each heat receiving wiring is connected to a different internal wiring. According to this, the heat transmitted to each heat receiving wiring can be conducted to different internal wiring.

請求項７に記載のように、電流配線の２本に分岐した部位の間に、これら２本に分岐した部位を接続する接続配線が設けられており、該接続配線と２本に分岐した部位とによって囲まれた複数の領域それぞれに、受熱配線が形成された構成が良い。 As described in claim 7, a connecting wiring for connecting the two branched portions is provided between the two portions of the current wiring, and the connecting wiring and the two branched portions. A structure in which a heat receiving wiring is formed in each of a plurality of regions surrounded by the lines is good.

これによれば、接続配線と受熱配線とが対向するので、１つの領域内に複数の受熱配線が配置された構成と比べて、放熱性が向上される。 According to this, since the connection wiring and the heat receiving wiring face each other, the heat dissipation is improved as compared with the configuration in which a plurality of heat receiving wirings are arranged in one region.

請求項８に記載のように、外部配線は、電子部品を実装面に機械的及び電気的に接続するはんだを溶かすリフロー時の熱を確保する集熱配線を有し、電流配線と集熱配線とは電気的に接続されており、その接続部位に、電流配線と集熱配線双方への熱伝導を抑制する複数の空隙が形成された構成が良い。 The external wiring has a heat collecting wiring for securing heat during reflow for melting the solder for mechanically and electrically connecting the electronic component to the mounting surface, and the current wiring and the heat collecting wiring. And a plurality of voids that suppress heat conduction to both the current wiring and the heat collecting wiring are preferable.

これによれば、はんだを溶かす際の熱が、集熱配線を介して電流配線に伝導されることが抑制される。これにより、はんだを溶かす熱が失われることが抑制される。また、実使用時において、外部配線にて生じた熱が、集熱配線へ伝達されることが抑制される。これにより、実使用時にてはんだが溶融することが抑制される。 According to this, heat at the time of melting the solder is suppressed from being conducted to the current wiring via the heat collecting wiring. Thereby, it is suppressed that the heat which melts solder is lost. In addition, during actual use, heat generated in the external wiring is suppressed from being transmitted to the heat collecting wiring. Thereby, it is suppressed that a solder melts at the time of actual use.

請求項９に記載のように、電流配線と集熱配線との接続部位に形成された空隙の一部は、受熱配線と電流配線との間の空隙である構成が良い。 According to a ninth aspect of the present invention, it is preferable that a part of the gap formed in the connection portion between the current wiring and the heat collecting wiring is a gap between the heat receiving wiring and the current wiring.

これによれば、配線基板の体格の増大が抑制される。 According to this, an increase in the size of the wiring board is suppressed.

第１実施形態に係る配線基板の概略構成を示す上面図である。It is a top view which shows schematic structure of the wiring board which concerns on 1st Embodiment. 図１のＩＩ−ＩＩ線に沿う断面図である。It is sectional drawing which follows the II-II line | wire of FIG. 図１に示す電流配線と集熱配線との接続部位を説明するための拡大上面図。The enlarged top view for demonstrating the connection site | part of the current wiring and heat collection wiring shown in FIG. 図１に示す受熱配線を説明するための上面図である。It is a top view for demonstrating the heat receiving wiring shown in FIG. 図４のＡ−Ａ線の基板温度を示すグラフである。It is a graph which shows the substrate temperature of the AA line of FIG. 図４のＢ−Ｂ線の基板温度を示すグラフである。It is a graph which shows the substrate temperature of the BB line of FIG. 配線基板の変形例を示す上面図である。It is a top view which shows the modification of a wiring board. 配線基板の変形例を示す上面図である。It is a top view which shows the modification of a wiring board. 配線基板の変形例を示す上面図である。It is a top view which shows the modification of a wiring board.

以下、本発明の実施の形態を図に基づいて説明する。
（第１実施形態）
図１は、第１実施形態に係る配線基板の概略構成を示す上面図である。図２は、図１のＩＩ−ＩＩ線に沿う断面図である。図３は、図１に示す電流配線と集熱配線との接続部位を説明するための拡大上面図である。図４は、図１に示す受熱配線を説明するための上面図である。図５は、図４のＡ−Ａ線の基板温度を示すグラフである。図６は、図４のＢ−Ｂ線の基板温度を示すグラフである。なお、図１では、電流の流れを破線矢印で示し、図１及び図２では、熱の伝導を白抜き矢印で示している。 Hereinafter, embodiments of the present invention will be described with reference to the drawings.
(First embodiment)
FIG. 1 is a top view showing a schematic configuration of the wiring board according to the first embodiment. 2 is a cross-sectional view taken along line II-II in FIG. FIG. 3 is an enlarged top view for explaining a connection portion between the current wiring and the heat collecting wiring shown in FIG. FIG. 4 is a top view for explaining the heat receiving wiring shown in FIG. FIG. 5 is a graph showing the substrate temperature along the line AA in FIG. FIG. 6 is a graph showing the substrate temperature along the line BB in FIG. In FIG. 1, the current flow is indicated by broken-line arrows, and in FIGS. 1 and 2, heat conduction is indicated by white arrows.

図１及び図２に示すように、配線基板１００は、要部として、絶縁材料から成る基板１０と、該基板１０における電子部品９０の実装面１０ａに形成された外部配線２０と、基板１０の内部に形成された内部配線３０と、基板１０における実装面１０ａと内部配線３０との間に形成されたビア４０と、を有する。本実施形態では、電子部品９０として、アルミ電解コンデンサが実装面１０ａに実装されており、該コンデンサの接続端子は、はんだを介して、外部配線２０と電気的に接続されている。そして、図２に示すように、実装面１０ａ、及び、その裏面は、保護膜１１によって覆われている。 As shown in FIGS. 1 and 2, the wiring substrate 100 includes, as main parts, a substrate 10 made of an insulating material, external wiring 20 formed on the mounting surface 10 a of the electronic component 90 on the substrate 10, The internal wiring 30 is formed inside, and the via 40 is formed between the mounting surface 10 a of the substrate 10 and the internal wiring 30. In this embodiment, an aluminum electrolytic capacitor is mounted on the mounting surface 10a as the electronic component 90, and the connection terminal of the capacitor is electrically connected to the external wiring 20 via solder. As shown in FIG. 2, the mounting surface 10 a and the back surface thereof are covered with a protective film 11.

外部配線２０は、電流の流れる電流配線２１と、該電流配線２１にて発生した熱を受熱する受熱配線２２と、リフロー方式にて電子部品９０をはんだ付けする際の熱を確保する集熱配線２３と、を有する。本実施形態では、一つの電流配線２１に一つの集熱配線２３が接続されてなる集合配線が、実装面１０ａに２つ形成されており、各集合配線の集熱配線２３に、電子部品９０の接続端子がはんだ付けされている。また、２つの集合配線の内の一方に、一つの電流配線２１が電気的に接続されており、一方の集合配線から一つの電流配線２１に電流が流れるようになっている。 The external wiring 20 includes a current wiring 21 through which a current flows, a heat receiving wiring 22 that receives heat generated in the current wiring 21, and a heat collecting wiring that secures heat when soldering the electronic component 90 by the reflow method. 23. In the present embodiment, two collective wirings formed by connecting one heat collecting wiring 23 to one current wiring 21 are formed on the mounting surface 10a, and the electronic component 90 is provided on the heat collecting wiring 23 of each collective wiring. The connection terminals are soldered. In addition, one current wiring 21 is electrically connected to one of the two collective wirings, and a current flows from one collective wiring to one current wiring 21.

図３に示すように、電流配線２１と集熱配線２３との接続部位には、幾つかの空隙２４が形成され、その接続面積が低減されている。この隙間により、電流配線２１と集熱配線２３双方への熱伝導が抑制される。すなわち、リフロー時に集熱配線２３にて蓄えられた熱が、電流配線２１へ伝導することが抑制され、電流配線２１に電流が流れている時（実使用時）に電流配線２１にて生じた熱が、集熱配線２３に伝導されることが抑制される。ちなみに、図３に示すように、電流配線２１と受熱配線２２とは、所定の間隔を置いて形成されているが、その２つの配線２１，２２間の空隙が、上記した、電流配線２１と集熱配線２３との接続部位に形成された空隙２４の一部を担っている。なお、保護膜１１には、溶けたはんだの流出を防ぐ環状のレジスト１２が形成されており、このレジスト１２によって、はんだが囲まれている。 As shown in FIG. 3, several gaps 24 are formed in the connection portion between the current wiring 21 and the heat collecting wiring 23, and the connection area is reduced. Due to this gap, heat conduction to both the current wiring 21 and the heat collecting wiring 23 is suppressed. That is, the heat stored in the heat collection wiring 23 during reflow is suppressed from being conducted to the current wiring 21, and is generated in the current wiring 21 when a current flows through the current wiring 21 (in actual use). It is suppressed that heat is conducted to the heat collecting wiring 23. Incidentally, as shown in FIG. 3, the current wiring 21 and the heat receiving wiring 22 are formed at a predetermined interval, but the gap between the two wirings 21 and 22 is the same as that of the current wiring 21 described above. It bears a part of the gap 24 formed at the connection site with the heat collecting wiring 23. The protective film 11 is formed with an annular resist 12 that prevents the melted solder from flowing out. The resist 12 surrounds the solder.

内部配線３０は、外部電源に接続される電源配線（図示略）と、グランドに接続されるグランド配線３１と、電気信号が流れる信号配線（図示略）と、を有する。図２では、上記した各内部配線の内、グランド配線３１のみを明示している。グランド配線３１と電源配線は、信号配線よりも線幅が広く、抵抗が小さくなっている。 The internal wiring 30 has a power supply wiring (not shown) connected to an external power supply, a ground wiring 31 connected to the ground, and a signal wiring (not shown) through which an electric signal flows. FIG. 2 shows only the ground wiring 31 among the above-described internal wirings. The ground wiring 31 and the power supply wiring are wider than the signal wiring and have a smaller resistance.

ビア４０は、電源配線と電気的に接続された電源ビア４１と、グランド配線３１と電気的に接続されたグランドビア４２と、信号配線と電気的に接続された信号ビア（図示略）と、を有する。図１に示すように、電源ビア４１は、一方の集合配線の電流配線２１における、集熱配線２３との接続端とは反対の端部に形成され、グランドビア４２の一部は、他方の集合配線の電流配線２１における、集熱配線２３との接続端とは反対の端部に形成されている。そして、グランドビア４２の残りは、受熱配線２２の端部に形成されている。この構成により、電流配線２１にて生じた熱が、受熱配線２２に伝導されると、その熱は、グランドビア４２を介して、グランド配線３１に伝導される。受熱配線２２の端部に形成されたグランドビア４２が、特許請求の範囲に記載の受熱ビアに相当する。 The via 40 includes a power supply via 41 electrically connected to the power supply wiring, a ground via 42 electrically connected to the ground wiring 31, a signal via (not shown) electrically connected to the signal wiring, Have As shown in FIG. 1, the power supply via 41 is formed at the end of the current wiring 21 of one aggregate wiring opposite to the connection end with the heat collecting wiring 23, and a part of the ground via 42 is formed on the other wiring The current wiring 21 of the collective wiring is formed at the end opposite to the connection end with the heat collecting wiring 23. The remainder of the ground via 42 is formed at the end of the heat receiving wiring 22. With this configuration, when the heat generated in the current wiring 21 is conducted to the heat receiving wiring 22, the heat is conducted to the ground wiring 31 through the ground via 42. The ground via 42 formed at the end of the heat receiving wiring 22 corresponds to the heat receiving via described in the claims.

次に、本実施形態に係る配線基板１００の特徴点を説明する。図１及び図４に示すように、電源ビア４１が端部に形成された電流配線２１は、電源ビア４１の形成された端部から、集熱配線２３が接続された端部に向かう途中で、２本に分岐した形状を成している。この分岐形状により、電源ビア４１から供給された電流は、図１に示すように、２手に分かれて、２本に分岐した部位それぞれにて熱が発生する。受熱配線２２は、２本に分岐した部位にて囲まれた領域内に、所定の間隔を空けて形成されており、分岐した部位にて生じた熱が、受熱配線２２に伝導されるようになっている。受熱配線２２に伝導された熱は、グランドビア４２を介して、グランド配線３１へと伝導される。 Next, features of the wiring board 100 according to the present embodiment will be described. As shown in FIGS. 1 and 4, the current wiring 21 in which the power supply via 41 is formed at the end portion is on the way from the end portion in which the power supply via 41 is formed to the end portion to which the heat collecting wiring 23 is connected. It has a bifurcated shape. Due to this branching shape, the current supplied from the power supply via 41 is divided into two hands as shown in FIG. 1, and heat is generated at each of the two branches. The heat receiving wiring 22 is formed at a predetermined interval in a region surrounded by the two branched portions so that heat generated at the branched portions is conducted to the heat receiving wiring 22. It has become. The heat conducted to the heat receiving wiring 22 is conducted to the ground wiring 31 through the ground via 42.

図１に示すように、受熱配線２２は一方向（電流の流動方向）に延びた形状を成し、その横幅が、グランドビア４２との接続部位よりも、該接続部位から延びた部位の方が短くなっている。具体的に言えば、受熱配線２２の両端部は、円形を成し、その中央部が、円形の直径よりも横幅の短い矩形を成している。そして、受熱配線２２の平面形状と、電流配線２１における２本に分岐した部位にて囲まれた領域の平面形状とは、相似であり、両者の間の対向間隔が一定となっている。 As shown in FIG. 1, the heat receiving wiring 22 has a shape extending in one direction (current flow direction), and its lateral width is greater in the portion extending from the connection portion than in the connection portion with the ground via 42. Is shorter. Specifically, both end portions of the heat receiving wiring 22 form a circle, and the central portion thereof forms a rectangle whose lateral width is shorter than the diameter of the circle. The planar shape of the heat receiving wiring 22 and the planar shape of the region surrounded by the two branches in the current wiring 21 are similar, and the facing distance between them is constant.

次に、図５，６に基づいて、基板１０におけるＡ−Ａ線及びＢ−Ｂ線の熱分布を説明する。図５，６それぞれの縦軸は、基板温度［℃］を示し、横軸は、基板長さ（距離［ｍｍ］）を示している。図５，６には、本実施形態に記載の構成（本発明）の他、比較対象として、電流配線２１が分岐していなく、集熱配線２３が実装面１０ａに形成されていない場合（分岐なし）、及び、電流配線２１が分岐しているが、集熱配線２３が実装面１０ａに形成されていない場合（分岐あり）それぞれの基板温度が示されている。 Next, the heat distribution of the AA line and the BB line in the substrate 10 will be described with reference to FIGS. 5 and 6, the vertical axis represents the substrate temperature [° C.], and the horizontal axis represents the substrate length (distance [mm]). 5 and 6, in addition to the configuration described in the present embodiment (the present invention), as a comparison object, the current wiring 21 is not branched and the heat collecting wiring 23 is not formed on the mounting surface 10a (branching). None) and when the current wiring 21 is branched but the heat collecting wiring 23 is not formed on the mounting surface 10a (with branching), the respective substrate temperatures are shown.

図５における、距離−０．５〜０．５ｍｍは、集熱配線２３のおおよその横幅、距離０．５〜１ｍｍ、及び、距離−０．５〜−１ｍｍは、分岐した電流配線２１それぞれの横幅を示している。図５に示すように、分岐なしの構成では、分岐ありの構成、及び、本発明の構成それぞれよりも基板温度が全領域で高く、分岐ありの構成は、本発明の構成よりも基板温度が全領域で高くなっている。特に、温度分布の顕著な違いは、分岐なしの構成では、おおよそ距離−１．０〜１．０ｍｍの間で基板温度が一定となっているのに対して、分岐ありの構成、及び、本発明の構成の場合、おおよそ距離−０．５〜０．５ｍｍの間（電流配線２１の非形成領域）の基板温度が、おおよそ距離０．５〜１ｍｍ、及び、距離−０．５〜−１ｍｍの間（電流配線２１の形成領域）の基板温度よりも低くなっている。また、おおよそ距離−０．５〜０．５ｍｍの間では、本発明の構成の方が、分岐ありの構成よりも温度が低くなっている。これは、受熱配線２２に伝導された熱が、グランドビア４２を介してグランド配線３１に伝導されるためである。 In FIG. 5, the distance −0.5 to 0.5 mm is the approximate lateral width of the heat collecting wiring 23, the distance 0.5 to 1 mm, and the distance −0.5 to −1 mm are the respective current wirings 21 branched. The width is shown. As shown in FIG. 5, in the configuration without branching, the substrate temperature is higher in all regions than the configuration with branching and the configuration of the present invention, and the configuration with branching has a substrate temperature higher than that of the configuration of the present invention. High in all areas. In particular, the remarkable difference in temperature distribution is that the substrate temperature is approximately constant between the distances of -1.0 to 1.0 mm in the configuration without branching, whereas the configuration with branching and this In the case of the configuration of the invention, the substrate temperature at a distance of approximately -0.5 to 0.5 mm (the region where the current wiring 21 is not formed) is approximately a distance of 0.5 to 1 mm and a distance of -0.5 to -1 mm. The temperature is lower than the substrate temperature in the interval (formation region of the current wiring 21). Further, at a distance of approximately -0.5 to 0.5 mm, the temperature of the configuration of the present invention is lower than that of the configuration with branching. This is because the heat conducted to the heat receiving wiring 22 is conducted to the ground wiring 31 through the ground via 42.

図６における、距離−９．０〜９．０ｍｍは、受熱配線２２の長さを示している。図６に示すように、分岐なしの構成、分岐ありの構成、及び、本発明の構成それぞれは、全領域にて、ほぼ同等の温度分布を形成するが、基板温度の高さには差が生じている。本発明の構成では、おおよそ距離−９．０〜９．０ｍｍの間（受熱配線２２の形成領域）では、分岐なしの構成、及び、分岐ありの構成それぞれよりも基板温度が低くなっている。これは、受熱配線２２に伝導された熱が、グランドビア４２を介してグランド配線３１に伝導されるためである。 In FIG. 6, the distance −9.0 to 9.0 mm indicates the length of the heat receiving wiring 22. As shown in FIG. 6, the configuration without branching, the configuration with branching, and the configuration of the present invention each form substantially the same temperature distribution in the entire region, but there is a difference in the height of the substrate temperature. Has occurred. In the configuration of the present invention, the substrate temperature is lower than the configuration without branching and the configuration with branching in a distance of approximately -9.0 to 9.0 mm (formation region of the heat receiving wiring 22). This is because the heat conducted to the heat receiving wiring 22 is conducted to the ground wiring 31 through the ground via 42.

以上、示したように、本発明の構成の場合、上記した２つの比較構成と比べて、基板温度が低くなっている。 As described above, in the case of the configuration of the present invention, the substrate temperature is lower than that of the two comparative configurations described above.

次に、本実施形態に係る配線基板１００の作用効果を説明する。上記したように、電流配線２１にて生じた熱を受熱する受熱配線２２が、実装面１０ａに形成されている。これによれば、搭載面にジャンパーリード線が接続される構成とは異なり、配線基板１００の厚さ方向の体格の増大が抑制されつつ、配線基板１００の放熱性が向上される。 Next, the function and effect of the wiring board 100 according to the present embodiment will be described. As described above, the heat receiving wiring 22 that receives the heat generated in the current wiring 21 is formed on the mounting surface 10a. According to this, unlike the configuration in which the jumper lead wire is connected to the mounting surface, an increase in the physique in the thickness direction of the wiring board 100 is suppressed, and the heat dissipation of the wiring board 100 is improved.

また、電流配線２１における２本に分岐した部位にて囲まれた領域内に、所定の間隔を空けて受熱配線２２が形成されている。これによれば、１本の電流配線と受熱配線とが所定の間隔を空けて隣接配置された構成と比べて、電流配線２１と受熱配線２２との対向面積が大きくなるので、電流配線２１にて生じた熱が、受熱配線２２に多く伝導される。これにより、放熱性が向上される。 In addition, the heat receiving wiring 22 is formed at a predetermined interval in a region surrounded by the two branches in the current wiring 21. According to this, since the facing area between the current wiring 21 and the heat receiving wiring 22 is larger than the configuration in which one current wiring and the heat receiving wiring are arranged adjacent to each other with a predetermined space therebetween, A large amount of the generated heat is conducted to the heat receiving wiring 22. Thereby, heat dissipation is improved.

受熱配線２２の平面形状と、電流配線２１における２本に分岐した部位にて囲まれた領域の平面形状とは、相似であり、両者の間の対向間隔が一定となっている。これによれば、受熱配線の平面形状と、電流配線における２本に分岐した部位にて囲まれた領域の平面形状とが相似でない構成、若しくは、両者が相似であるが、両者の間の対向間隔が不定である構成と比べて、電流配線２１と受熱配線２２との対向面積が大きくなる。そのため、電流配線２１にて生じた熱が、受熱配線２２に多く伝導され、放熱性が向上される。 The planar shape of the heat receiving wiring 22 and the planar shape of the region surrounded by the two branches in the current wiring 21 are similar, and the facing distance between them is constant. According to this, the configuration in which the planar shape of the heat receiving wiring and the planar shape of the region surrounded by the two branches in the current wiring are not similar, or both are similar, but the two are facing each other Compared with the configuration in which the interval is indefinite, the facing area between the current wiring 21 and the heat receiving wiring 22 is increased. Therefore, much heat generated in the current wiring 21 is conducted to the heat receiving wiring 22 and heat dissipation is improved.

受熱配線２２は一方向（電流の流動方向）に延びた形状を成し、その横幅が、グランドビア４２との接続部位よりも、該接続部位から延びた部位の方が短くなっている。これによれば、電流配線２１と受熱配線２２との対向面積、及び、配線基板１００の面積を変えずに、電流配線２１の形成面積を大きくすることができる。そのため、受熱配線２２が電流配線２１から受け取る熱量の低減、及び、配線基板１００の体格の増大が抑制されつつ、電流配線２１にて生じる熱量を少なくすることができる。 The heat receiving wiring 22 has a shape extending in one direction (current flow direction), and the width of the heat receiving wiring 22 is shorter at the portion extending from the connection portion than at the connection portion with the ground via 42. According to this, the formation area of the current wiring 21 can be increased without changing the facing area between the current wiring 21 and the heat receiving wiring 22 and the area of the wiring substrate 100. Therefore, the amount of heat generated in the current wiring 21 can be reduced while the reduction in the amount of heat received by the heat receiving wiring 22 from the current wiring 21 and the increase in the size of the wiring board 100 are suppressed.

電流配線２１と集熱配線２３との接続部位には、幾つかの空隙２４が形成され、この隙間により、電流配線２１と集熱配線２３双方への熱の伝導が抑制される。すなわち、リフロー時に集熱配線２３にて蓄えられた熱が、電流配線２１へ伝導することが抑制され、電流配線２１に電流が流れている時（実使用時）に電流配線２１にて生じた熱が、集熱配線２３に伝導されることが抑制される。これにより、リフロー時に、はんだを溶かす熱が失われることが抑制され、実使用時に、はんだが溶融することが抑制される。 Several gaps 24 are formed at the connection portion between the current wiring 21 and the heat collecting wiring 23, and the conduction of heat to both the current wiring 21 and the heat collecting wiring 23 is suppressed by this gap. That is, the heat stored in the heat collection wiring 23 during reflow is suppressed from being conducted to the current wiring 21, and is generated in the current wiring 21 when a current flows through the current wiring 21 (in actual use). It is suppressed that heat is conducted to the heat collecting wiring 23. Thereby, it is suppressed that the heat which melts solder is lost at the time of reflow, and it is controlled that solder melts at the time of actual use.

電流配線２１と受熱配線２２とは、所定の間隔を置いて形成されているが、その２つの配線２１，２２間の空隙が、上記した、電流配線２１と集熱配線２３との接続部位に形成された空隙２４の一部を担っている。これによれば、配線基板１００の体格の増大が抑制される。 The current wiring 21 and the heat receiving wiring 22 are formed at a predetermined interval. The gap between the two wirings 21 and 22 is formed at the connection portion between the current wiring 21 and the heat collecting wiring 23 described above. It bears a part of the formed gap 24. According to this, an increase in the size of the wiring board 100 is suppressed.

以上、本発明の好ましい実施形態について説明したが、本発明は上記した実施形態になんら制限されることなく、本発明の主旨を逸脱しない範囲において、種々変形して実施することが可能である。 The preferred embodiments of the present invention have been described above. However, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention.

本実施形態では、受熱配線２２は、電流配線２１における２本に分岐した部位にて囲まれた領域内だけに形成された例を示した。しかしながら、受熱配線２２の形成としては、上記例に限定されず、例えば、図７に示すように、実装面１０ａにおける、電流配線２１の２本に分岐した部位にて囲まれた領域以外の領域にも、電流配線２１と所定の間隔を空けて、受熱配線２２が形成された構成を採用することもできる。これによれば、更に放熱性が向上される。図７は、配線基板の変形例を示す上面図である。 In the present embodiment, an example in which the heat receiving wiring 22 is formed only in the region surrounded by the two branches in the current wiring 21 is shown. However, the formation of the heat receiving wiring 22 is not limited to the above example. For example, as shown in FIG. 7, the area other than the area surrounded by the two branched portions of the current wiring 21 on the mounting surface 10a. In addition, a configuration in which the heat receiving wiring 22 is formed at a predetermined interval from the current wiring 21 may be employed. According to this, heat dissipation is further improved. FIG. 7 is a top view showing a modified example of the wiring board.

本実施形態では、電流配線２１における２本に分岐した部位にて囲まれた領域が１つである例を示した。しかしながら、例えば、図８に示すように、実装面１０ａにおける、電流配線２１の２本に分岐した部位の間に、これら２本の分岐した部位を接続する接続配線２５が設けられ、接続配線２５と２本に分岐した部位とによって囲まれた２つの領域それぞれに、受熱配線２２が形成された構成を採用することもできる。これによれば、接続配線２５と各受熱配線２２とが対向するため、１つの領域内に複数の受熱配線が配置された構成と比べて、放熱性が向上される。なお、接続配線２５の数としては、上記例に限定されず、２つ以上を採用することもできる。図８は、配線基板の変形例を示す上面図である。 In the present embodiment, an example in which there is one region surrounded by the two branches of the current wiring 21 is shown. However, for example, as illustrated in FIG. 8, a connection wiring 25 that connects the two branched portions is provided between the two branched portions of the current wiring 21 on the mounting surface 10 a. It is also possible to adopt a configuration in which the heat receiving wiring 22 is formed in each of the two regions surrounded by the two branches. According to this, since the connection wiring 25 and each heat receiving wiring 22 face each other, heat dissipation is improved as compared with a configuration in which a plurality of heat receiving wirings are arranged in one region. Note that the number of connection wirings 25 is not limited to the above example, and two or more connection wirings 25 may be employed. FIG. 8 is a top view showing a modification of the wiring board.

本実施形態では、受熱配線２２の両端部は、円形を成し、その中央部が、円形の直径よりも横幅の短い矩形を成した例を示した。しかしながら、受熱配線２２の平面形状としては、上記例に限定されず、例えば、図９に示すように、受熱配線２２の両端部、及び、中央部が正方形、両端部と中央部それぞれを連結する連結部が、横幅が正方形の一辺の長さよりも短い矩形である平面形状を採用することもできる。図９においても、受熱配線２２の平面形状と、電流配線２１における２本に分岐した部位にて囲まれた領域の平面形状とは相似であり、両者の間の対向間隔が一定となっているが、この構成であれば、本実施形態で示した構成と比べて、受熱配線２２と電流配線２１との対向面積が増大するので、放熱性がより向上される。なお、もちろんであるが、受熱配線２２の平面形状としては、上記例に限定されず、いかなる形状であっても良い。図９は、配線基板の変形例を示す上面図である。 In the present embodiment, an example is shown in which both end portions of the heat receiving wiring 22 have a circular shape, and a central portion thereof has a rectangular shape whose lateral width is shorter than the circular diameter. However, the planar shape of the heat receiving wiring 22 is not limited to the above example. For example, as shown in FIG. 9, both ends and the center of the heat receiving wiring 22 are square, and both ends and the center are connected. A planar shape in which the connecting portion is a rectangle whose lateral width is shorter than the length of one side of the square can also be adopted. Also in FIG. 9, the planar shape of the heat receiving wiring 22 is similar to the planar shape of the region surrounded by the two branches in the current wiring 21, and the facing distance between them is constant. However, with this configuration, since the facing area between the heat receiving wiring 22 and the current wiring 21 is increased as compared with the configuration shown in the present embodiment, heat dissipation is further improved. Needless to say, the planar shape of the heat receiving wiring 22 is not limited to the above example, and may be any shape. FIG. 9 is a top view showing a modification of the wiring board.

本実施形態では、受熱配線２２が、グランドビア４２を介して、グランド配線３１に接続された例を示した。しかしながら、受熱配線２２が、信号ビアを介して、信号配線に接続された構成を採用することもできる。しかしながら、通常、信号配線は、グランド配線３１や電源配線よりも横幅が短く、熱を他の部位に伝導するのに適していない。そのため、上記構成を採用する場合、実装面１０ａに、複数の受熱配線２２を形成し、それぞれが、異なる信号配線に接続された構成が好ましい。これによれば、各受熱配線２２に伝達された熱を、異なる信号配線に伝導することができる。 In the present embodiment, an example in which the heat receiving wiring 22 is connected to the ground wiring 31 through the ground via 42 is shown. However, a configuration in which the heat receiving wiring 22 is connected to the signal wiring through the signal via can also be adopted. However, the signal wiring usually has a shorter width than the ground wiring 31 and the power supply wiring, and is not suitable for conducting heat to other parts. Therefore, when adopting the above configuration, a configuration in which a plurality of heat receiving wirings 22 are formed on the mounting surface 10a and each is connected to a different signal wiring is preferable. According to this, the heat transmitted to each heat receiving wiring 22 can be conducted to different signal wiring.

本実施形態では、電流配線２１と受熱配線２２との間の隙間について、特に言及しなかった。しかしながら、電流配線２１と受熱配線２２との間に、絶縁性及び熱伝導性を有する熱伝導媒体（図示略）が設けられた構成を採用することもできる。これによれば、熱伝導媒体を介して、電流配線２１と受熱配線２２とが熱的に接続されるので、電流配線と受熱配線との間に熱伝導媒体が設けられていない構成と比べて、電流配線２１にて生じた熱が、受熱配線２２に多く伝導される。これにより、放熱性が向上される。 In the present embodiment, the gap between the current wiring 21 and the heat receiving wiring 22 is not particularly mentioned. However, a configuration in which a heat conductive medium (not shown) having insulating properties and heat conductivity is provided between the current wiring 21 and the heat receiving wiring 22 may be employed. According to this, since the current wiring 21 and the heat receiving wiring 22 are thermally connected via the heat conducting medium, compared to a configuration in which no heat conducting medium is provided between the current wiring and the heat receiving wiring. A large amount of heat generated in the current wiring 21 is conducted to the heat receiving wiring 22. Thereby, heat dissipation is improved.

１０・・・基板
２０・・・外部配線
２１・・・電流配線
２２・・・受熱配線
２３・・・集熱配線
４０・・・ビア
４１・・・電源ビア
４２・・・グランドビア
９０・・・電子部品
１００・・・配線基板 DESCRIPTION OF SYMBOLS 10 ... Board | substrate 20 ... External wiring 21 ... Current wiring 22 ... Heat receiving wiring 23 ... Heat collection wiring 40 ... Via 41 ... Power supply via 42 ... Ground via 90 ...・ Electronic component 100: wiring board

Claims

A substrate made of an insulating material;
External wiring formed on the mounting surface of the electronic component on the substrate;
Internal wiring formed inside the substrate;
A wiring board having a via formed between the mounting surface of the board and the internal wiring,
The external wiring has a current wiring through which a current flows, and a heat receiving wiring that receives heat generated in the current wiring,
The via has a heat receiving via that electrically connects the heat receiving wiring and the internal wiring;
The current wiring has a shape branched into two,
The wiring board, wherein the heat receiving wiring is formed in a region surrounded by a bifurcated portion of the current wiring at a predetermined interval.

The planar shape of the heat receiving wiring is similar to the planar shape of the region surrounded by the two branches in the current wiring, and the facing distance between the two is constant. Item 4. The wiring board according to Item 1.

A heat conduction medium having insulation and thermal conductivity is provided between the heat receiving wiring and the current wiring, and the heat receiving wiring and the current wiring are thermally connected via the heat conduction medium. The wiring board according to claim 1, wherein the wiring board is provided.

The heat receiving wiring has a shape extending in one direction, and a lateral width of the heat receiving wiring is shorter in a portion extending from the connection portion than in a connection portion with the heat receiving via. The wiring board according to claim 1.

The heat receiving wiring is formed in a region other than the region surrounded by the two branches of the current wiring on the mounting surface with a predetermined interval from the current wiring. The wiring board according to any one of claims 1 to 4.

The wiring board according to claim 1, wherein the plurality of heat receiving wirings are connected to different internal wirings.

Between the two branched portions of the current wiring, a connection wiring for connecting the two branched portions is provided,
The wiring board according to claim 1, wherein the heat receiving wiring is formed in each of a plurality of regions surrounded by the connection wiring and the two branched portions.

The external wiring has a heat collecting wiring that secures heat during reflow for melting the solder that mechanically and electrically connects the electronic component to the mounting surface,
The current wiring and the heat collection wiring are electrically connected, and a plurality of gaps that suppress heat conduction to both the current wiring and the heat collection wiring are formed at the connection portion. The wiring board according to any one of claims 1 to 7.

The wiring board according to claim 8, wherein a part of a gap formed at a connection portion between the current wiring and the heat collection wiring is a gap between the heat receiving wiring and the current wiring.