Circuit board and electronic control unit

Abstract

A circuit board comprises: a substrate body; a first electronic component; a contact-prevention component; and an electronic component with an attached cover. Regarding the contact-prevention component, the projection heights of the first electronic component and the contact-prevention component from a mounting surface are set to be greater than the projection height of the electronic component with the attached cover. A first upper end portion of the electronic component with the attached cover, on a side facing the first electronic component, is contained within a space formed by a line connecting a first upper end portion and a mounting end portion of the contact-prevention component on a side facing the mounting surface, and the mounting surface itself.A second upper end section of the electronic component with an attached cover on one side facing the contact prevention component is contained in a space formed by a line connecting an upper end section of the contact prevention component and a mounting end section of the first electronic component on one side with the mounting surface, and the mounting surface.

Description

Technical field

[0001] The present invention relates to a circuit board and an electronic control device. background

[0002] An electronic control unit (ECU) with an electronic component for controlling the vehicle is located in an automobile. In recent years, the ECU installed in a vehicle has been required to possess high computing power to implement high-performance driver assistance systems such as collision avoidance braking systems and automated driving. For this reason, the ECU incorporates numerous crystal resonators and crystal oscillators that enable stable signal synchronization at high speeds. These electronic components, exemplified by ceramic housings and crystal resonators, are covered with lids. Hereinafter, such an electronic component will be referred to as a lidded electronic component.To prevent a top-mounted cover from being detached due to contact during an inspection process, it is necessary to avoid external stress on the electronic component with the cover attached.

[0003] One technique for this purpose is described in PTL 1. PTL 1 describes a technique in which, on a circuit board with multiple electronic components mounted on it, the electronic components to be protected are positioned near an electronic component that is taller than the other electronic components. In this case, the protected electronic components are arranged so that they are completely contained within a space defined by a point on the electronic component on a side facing the electronic component, a mounting surface of the circuit board, and a plane passing through one end of the circuit board and tangent to the top of the electronic component. Citation list for patent literature

[0004] PTL 1: JP 2002-43715 A Overview of the invention Technical problem

[0005] The technique described in PTL 1 protects electronic components from loads applied from above perpendicular to a substrate plane; however, it does not protect them from loads applied from a side parallel to the substrate plane. Consequently, with the technique described in PTL 1, there is a possibility that a cover of an electronic component could be detached by stress during an inspection process or similar operation.

[0006] Taking into account the problem mentioned above, one objective of the present invention is to provide a circuit board and an electronic control device capable of protecting an electronic component with an attached cover from external stress. Solution to the problem

[0007] To solve the above problem and achieve the goal, a circuit board contains: a substrate body; a first electronic component mounted on a mounting surface of the substrate body; a contact-prevention component; and an electronic component with an attached cover. The contact-prevention component is mounted on the mounting surface of the substrate body and is positioned closer to an end section of the substrate body than the first electronic component. The electronic component with the attached cover is mounted on the mounting surface of the substrate body and is positioned between the first electronic component and the contact-prevention component. The overhang heights of the first electronic component and the contact-prevention component from the mounting surface are adjusted to be greater than the overhang height of the electronic component with the attached cover.

[0008] A first upper end section of the electronic component, with a cover attached on one side facing the first electronic component, is contained within a space formed by a line connecting an upper end section of the first electronic component and a mounting end section of the contact-prevention component on one side to the mounting surface, and the mounting surface itself. A second upper end section of the electronic component, with a cover attached on one side facing the contact-prevention component, is contained within a space formed by a line connecting an upper end section of the contact-prevention component and a mounting end section of the first electronic component on one side to the mounting surface, and the mounting surface itself.

[0009] An electronic control device contains a circuit board and a connector. The circuit board used is the one described above. Advantageous effects of the invention

[0010] According to the circuit board and the electronic control unit with the configurations described above, it is possible to protect the electronic components from external stress with the cover attached. Brief description of the drawings [ Fig. 1] Fig. Figure 1 is an external view showing a circuit board of an electronic control device according to a first embodiment. [ Fig. 2] Fig. Figure 2 is a cross-sectional view showing the circuit board according to the first embodiment. [ Fig. 3] Fig. Figure 3 is a cross-sectional view showing a conventional circuit board. [ Fig. 4] Fig. Figure 4 is a top view showing the circuit board according to the first embodiment. [ Fig. 5] Fig. Figure 5 shows a state in which a connector is mounted on the circuit board according to the first embodiment, wherein Fig. 5A is a front view and Fig. 5B is a rear view. [ Fig. 6] Fig. Figure 6 is a cross-sectional view showing a circuit board according to a second embodiment. Description of the embodiments

[0011] The following describes embodiments of an electronic control device and a circuit board with reference to the Fig. Sections 1 to 6 are described. In the drawings, the same elements are designated with the same reference symbols. 1. First embodiment

[0012] First, configurations of an electronic control device and a circuit board according to a first embodiment (hereinafter referred to as the "present example") are described with reference to the Fig. 1 to 5B described.

[0013] Fig. Figure 1 is a top view showing a circuit board of an electronic control device, and Fig. Figure 2 is a cross-sectional view showing the electronic control device.

[0014] The in the Fig. 1 and Fig. The device shown in Figure 2 is a circuit board of an electronic control unit that is mounted in an automobile and controls the automobile. As shown in the Fig. 1 and Fig. As shown in Figure 2, a circuit board 100 contains a plate-like substrate body 10, a first electronic component 1, a second electronic component 2 and a third electronic component 3.

[0015] The first electronic component 1, the second electronic component 2, and the third electronic component 3 are mounted on a mounting surface 10b of the substrate body 10. Electronic components with lower failure rates under external stress than those of the third electronic component 3, described later, are used for the first electronic component 1 and the second electronic component 2. For example, a capacitor, a system-on-a-chip (SoC), and the like are used as the first electronic component 1 and the second electronic component 2. In the present example, an SoC is used as the first electronic component 1, and a capacitor or a dummy capacitor is used as the second electronic component 2.

[0016] The second electronic component 2, which is a contact-prevention component, is located closer to an end section 10a of the substrate body 10 than the first electronic component 1 and the third electronic component 3. The third electronic component 3 is located closer to the end section 10a of the substrate body 10 than the first electronic component 1. The third electronic component 3 is located near the first electronic component 1 and the second electronic component 2. In particular, the third electronic component 3 is located between the first electronic component 1 and the second electronic component 2. That is, the third electronic component 3 is arranged in such a way that it is sandwiched between the first electronic component 1 and the second electronic component 2.

[0017] The third electronic component 3 is an electronic component with an attached cover; that is, an electronic component whose failure rate under external stresses is higher than that of the first electronic component 1 and the second electronic component 2. The third electronic component 3 is a ceramic housing product such as a gyroscope or a crystal resonator. In the present example, a crystal resonator is used as the third electronic component 3.

[0018] The overhang heights of the first electronic component 1 and the second electronic component 2 from the mounting surface 10b are set such that they are higher than that of the third electronic component 3. Thus, the third electronic component 3, as shown in Fig. 2 shown, contained in a space formed by an upper end line P1 connecting an upper end section 1a of the first electronic component 1 and an upper end section 2a of the second electronic component 2, and the mounting surface 10b.

[0019] Fig. Figure 3 is a cross-sectional view showing a conventional circuit board.

[0020] As in Fig. As shown in Figure 3, a conventional circuit board 200 has a substrate body 10 on which a first electronic component 1, a second electronic component 21, and a third electronic component 3, which is an electronic component with an attached cover, are mounted. The third electronic component 3 is located between the first electronic component 1 and the second electronic component 21. Note that the overhang height of the second electronic component 21, which is mounted on one side of an end section 10a of the substrate body 10, is less than that of the third electronic component 3. The third electronic component 3 projects beyond an upper end section 21a of the second electronic component 21 in the overhang direction from the mounting surface 10b.

[0021] This means that, on the conventional circuit board 200, a finger, a test device, or the like can come into contact with the third electronic component 3 from the side of the end section 10a of the substrate body 10 during a test procedure or the like. As a result, there is a risk of the cover detaching from the third electronic component 3 due to external stress, leading to a failure of the third electronic component 3.

[0022] On the other hand, in circuit board 100, the first electronic component 1 and the second electronic component 2 are higher than the third electronic component 3, and the third electronic component 3 is contained within a space formed by the upper end line P1, which connects the upper end section 1a of the first electronic component 1 and the upper end section 2a of the second electronic component 2, and the mounting surface 10b. This prevents a finger, a test device, or the like from coming into contact with the third electronic component from the side of the end section 10a of the substrate body 10. Therefore, it is possible to protect the third electronic component, which is an electronic component with an attached cover, from external stress.

[0023] A first upper end section 3a of the third electronic component 3 on one side of the first electronic component 1 is contained in a space formed by a line P2, which connects the upper end section 1a of the first electronic component 1 and a mounting end section 2b of the second electronic component 2 on one side of the mounting surface 10b, and the mounting surface 10b. This can prevent a finger, a test device, or the like from coming into contact with the first upper end section 3a of the third electronic component 3 from the side of the first electronic component 1.

[0024] Furthermore, a second upper end section 3b of the third electronic component 3 is contained on one side of the second electronic component 2 in a space formed by a line P3 connecting the upper end section 2a of the second electronic component 2 and a mounting end section 1b of the first electronic component 1 on one side of the mounting surface 10b, and the mounting surface 10b. This prevents a finger, a test device, or the like from coming into contact with the second upper end section 3b of the third electronic component 3 from the side of the second electronic component 2.

[0025] Fig. Figure 4 is a top view showing the circuit board 100 of the present example.

[0026] As in Fig. As shown in Figure 4, the circuit board 100 of the present example has several second electronic components 2, 2 mounted on the substrate body 10. A gap between the several second electronic components 2 is set to be narrow enough to prevent the ingress of a finger, a test device, or the like. The length of the first electronic component 1 in a width direction parallel to the mounting surface 10b of the substrate body 10 is set to be longer than the length of the third electronic component 3 in the width direction. The total length of the several second electronic components 2, 2 from a first end section 2c to a second end section 2d in the width direction is set to be longer than the length of the third electronic component 3 in the width direction.

[0027] Here, a line extending parallel to the mounting surface 10b from the first end section 2c of the multiple second electronic components 2, 2 towards the first electronic component 1 is designated as the first line Q1. A line extending parallel to the mounting surface 10b from the second end section 2d of the multiple second electronic components 2, 2 towards the first electronic component 1 is designated as the second line Q2. At this time, the third electronic component 3 is positioned between the first line Q1 and the second line Q2. That is, if the first electronic component 1, the second electronic components 2, and the third electronic component 3 are considered from the end section 10a of the substrate body 10 in the direction parallel to the mounting surface 10b, the third electronic component 3 is covered by the second electronic components 2.Thus, the third electronic component 3 is contained in a space defined by the in . Fig. 2 shown upper end line P1, the first line Q1 and the second line Q2 as well as the mounting surface 10b are formed.

[0028] In this way, the third electronic component 3 is arranged such that it is surrounded by the first electronic component 1 and the second electronic components 2. Therefore, according to the circuit board 100 of the present example, it is possible to prevent a finger, a test device, or the like from coming into contact with the third electronic component 3 and to protect the third electronic component, which is an electronic component with an attached cover, from external stress.

[0029] The present example describes an instance in which several second electronic components 2 are mounted side by side, but the present invention is not limited thereto. The number of second electronic components 2 as contact-prevention components can also be only one. In this case, the length of a second electronic component 2 from a first end section 2c to a second end section 2d in the lateral direction is set such that it is longer than the length of the third electronic component 3 in the lateral direction.

[0030] The Fig. 5A and Fig. Figure 5B illustrates a state in which a connector is mounted on the circuit board 100 of the present example. Fig. 5A is a front view and Fig. 5B is a rear view.

[0031] Here, the third electronic component 3, if a crystal resonator is used as the third electronic component 3 (which is an electronic component with an attached cover), tends to be a source of interference. Therefore, when a connector 4, which is an interference-prone analog component, is mounted on the substrate body 10, the connector 4 is mounted on a rear surface opposite the mounting surface 10b on which the third electronic component 3 is mounted. That is, the connector 4 and the third electronic component 3 are positioned perpendicular to each other with respect to the mounting surface 10b of the substrate body 10. This can suppress the influence of interference from the third electronic component 3 on the connector 4. Consequently, it is not necessary to provide a component for EMC measures, and the costs can be reduced.

[0032] Note that the electronic control device is formed by mounting connector 4 on circuit board 100. 2. Second embodiment

[0033] Next, a circuit board according to a second embodiment is described with reference to Fig. 6 described.

[0034] Fig. Figure 6 is a cross-sectional view illustrating a circuit board according to the second embodiment.

[0035] A circuit board 100B according to the second embodiment differs from the circuit board 100 according to the first embodiment in that a ground connection is mounted. Therefore, while a protective element is described here, parts common to the circuit board 100 according to the first embodiment are designated by the same reference numerals, and redundant descriptions are omitted.

[0036] As in Fig.As shown in Figure 6, the circuit board 100B comprises a plate-like substrate body 10, a first electronic component 1, a second electronic component 2, a third electronic component 3, a signal ground 5, and a frame ground 6. Similar to the first electronic component 1, the second electronic component 2, and the third electronic component 3, the signal ground 5 and the frame ground 6 are mounted on a mounting surface 10b of the substrate body 10. The signal ground 5 and the frame ground 6 are mounted closer to an end section 10a of the substrate body 10 than the second electronic component 2.

[0037] The second electronic component 2 is connected to the signal ground 5 and the frame ground 6. By connecting this second electronic component 2, which is a contact-prevention component, to the various grounds mounted on the substrate body 10, it is possible to improve resistance to electromagnetic interference and implement EMC measures. Furthermore, using this second electronic component 2, which is also a contact-prevention component, as an EMC component also prevents an increase in the number of components and reduces the manufacturing cost of the circuit board 100B.

[0038] The other configurations are similar to those of circuit board 100 according to the first embodiment, and therefore their description is omitted. Circuit board 100B according to the second embodiment can also achieve the same operational effects as circuit board 100 according to the first embodiment described above.

[0039] Note that the present invention is not limited to the embodiments described above and illustrated in the drawings, and various modifications can be made without departing from the core of the invention described in the claims. Part of the configuration of a particular embodiment can be replaced by the configuration of another embodiment, and the configuration of another embodiment can be added to the configuration of a particular embodiment. Furthermore, it is possible to add, delete, and replace other configurations for part of the configuration of another embodiment.

[0040] The present description uses terms such as "parallel" and "orthogonal". However, these terms do not strictly mean only "parallel" and "orthogonal", but can also include states of "essentially parallel" and "essentially orthogonal", including "parallel" and "orthogonal", within a range in which the function can be exercised. Reference symbol list 1 first electronic component 1a upper end section 1b Assembly end section 2. Second electronic component (contact prevention component) 2a upper end section 2b Assembly end section 2c first end section 2d second end section 3 third electronic component (electronic component with attached cover) 3a first upper end section 3b second upper end section 4 connectors 5 Signal earth 6 frame soil 10 substrate bodies 10a Final section 10b Mounting surface 100, 100B circuit board P1 upper end line P2, P3 line Q1 first line Q2 second line QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] JP 2002-43715 A

[0004]

Claims

[1] Circuit board comprising: a substrate body; a first electronic component that is mounted on a mounting surface of the substrate body; a contact prevention component that is mounted on the mounting surface of the substrate body and is located closer to an end section of the substrate body than the first electronic component; and an electronic component with an attached cover, which is mounted on the mounting surface of the substrate body and positioned between the first electronic component and the contact prevention component, wherein the overhang heights of the first electronic component and the contact prevention component from the mounting surface are set such that they are higher than the overhang height of the electronic component with the cover attached, a first upper end section of the electronic component with attached cover on one side facing the first electronic component is contained in a space formed by a line connecting an upper end section of the first electronic component and a mounting end section of the contact prevention component on one side with the mounting surface, and the mounting surface, and a second upper end section of the electronic component with attached cover on one side facing the contact prevention component is contained in a space formed by a line connecting an upper end section of the contact prevention component and a mounting end section of the first electronic component on one side with the mounting surface, and the mounting surface. [2] Circuit board according to claim 1, wherein the electronic component with attached cover is arranged between a first line extending from a first end section of the contact prevention component in a width direction in a direction parallel to the mounting surface in the direction of the first electronic component, and a second line extending from a second end section of the contact prevention component in a width direction in the direction of the first electronic component. [3] Circuit board according to claim 1, wherein an earth connected to the contact prevention component is mounted on the substrate body. [4] Circuit board according to claim 1, wherein a connector is mounted on the substrate body, and the connector is mounted on a rear surface opposite the mounting surface on which the electronic component with the attached cover is mounted. [5] Circuit board according to claim 1, wherein the contact prevention component is a dummy capacitor. [6] Electronic control device comprising: a circuit board; and a connector mounted on the circuit board, the circuit board contains: a substrate body; a first electronic component that is mounted on a mounting surface of the substrate body; a contact prevention component that is mounted on the mounting surface of the substrate body and is located closer to an end section of the substrate body than the first electronic component; and an electronic component with an attached cover, which is mounted on the mounting surface of the substrate body and positioned between the first electronic component and the contact prevention component, wherein the overhang heights of the first electronic component and the contact prevention component from the mounting surface are set such that they are higher than the overhang height of the electronic component with the cover attached, a first upper end section of the electronic component with attached cover on one side facing the first electronic component is contained in a space formed by a line connecting an upper end section of the first electronic component and a mounting end section of the contact prevention component on one side with the mounting surface, and the mounting surface, and a second upper end section of the electronic component with attached cover on one side facing the contact prevention component is contained in a space formed by a line connecting an upper end section of the contact prevention component and a mounting end section of the first electronic component on one side with the mounting surface, and the mounting surface.

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