WO2018179853A1

WO2018179853A1 - Vehicle-mounted control device

Info

Publication number: WO2018179853A1
Application number: PCT/JP2018/003903
Authority: WO
Inventors: 真紀伊藤; 利昭石井; 河合　義夫; 房郎北條; 尭之福沢; 正人齋藤; 剛資近藤
Original assignee: 日立オートモティブシステムズ株式会社
Priority date: 2017-03-30
Filing date: 2018-02-06
Publication date: 2018-10-04
Also published as: JP2018170401A; JP6735248B2

Abstract

The purpose of the present invention is to provide a vehicle-mounted control device which is excellent in heat dissipation and capable of effectively increasing the amount of heat transfer from an electronic component and a circuit board to a case (a base and a cover). An electronic control device according to the present invention has: a circuit board; an electronic component mounted on the circuit board; a connecting member for connecting a terminal of an electronic component and the circuit board; and a heat radiation coating film that covers the circuit board and the terminal, wherein the thickness of the heat radiation coating film covering the terminal is set to 30 μm or greater.

Description

In-vehicle control device

The present invention relates to an in-vehicle control device such as an ECU (Electronic Control Unit) mounted on an automobile, and more particularly to a heat dissipation structure of an electronic control device having a thermal radiation coating film on a circuit board on which electronic components are mounted.

2. Description of the Related Art Conventionally, an in-vehicle control device (ECU) mounted on an automobile is usually configured to include a circuit board on which electronic components including heat-generating parts such as semiconductor elements are mounted, and a housing that accommodates the circuit board. . In the electronic component, for example, the terminal of the electronic component is fixed by attaching a joining member such as solder to the wiring circuit pattern of the circuit board. The casing is generally composed of a base that fixes the circuit board and a cover that is assembled to the base so as to cover the circuit board.

In such in-vehicle control devices, in recent years, the amount of heat generation tends to increase with downsizing due to space constraints and multi-functionality. Patent Document 1 proposes a heat dissipation technique in which heat treatment generated by an electronic component (heat generating element) is moved to a housing and heat-treated from the outer surface of the housing to the atmosphere to perform surface treatment on the housing. .

Further, as disclosed in Patent Document 2, a heat dissipation method is known in which a coating film is formed on the surface of a heat-generating component with a paint containing ceramic particles.

JP 2004-304200 A JP 2013-144746 A

In recent years, there has been a social demand to reduce the size of the engine room by increasing the density from the viewpoint of resource saving. In-vehicle control devices are also being reduced in size, and accordingly, the heat generation density is increased due to the reduction in the board area and the concentration of electronic components, and thus further improvement in heat dissipation is desired.

In the conventional proposed technology, the surface treatment applied to the surface of the housing absorbs heat from the heating element. However, the amount of heat transferred from the circuit board and the heating element to the housing is small and not sufficiently performed. There was a fear.

The present invention has been made in view of the above circumstances, and an object of the present invention is to dissipate heat that can effectively increase the amount of heat transfer from the electronic component and the circuit board to the housing (base and cover). An object of the present invention is to provide a vehicle-mounted control device that is excellent in performance.

In order to achieve the above object, an in-vehicle control device according to the present invention basically covers a circuit board on which electronic components are mounted by a joining member such as solder, a base to which the circuit board is fixed, and the circuit board. And a cover assembled to the base.
A heat radiation coating film is formed in a thick film on and around the terminal portion of the electronic component (heat generating element). In addition, the thermal radiation coating film formed on the terminal portion of the electronic component is characterized in that a concavo-convex shape is formed by the terminal of the electronic component.

According to the present invention, since the emissivity of the member that joins the terminal of the electronic component such as the terminal of the electronic component or solder and the circuit board, which has a low emissivity, and the surface area of the high emissivity is increased, the electronic component In addition, the amount of heat transfer from the circuit board to the housing can be increased. Therefore, the heat dissipation of the in-vehicle control device can be improved, and as a result, the temperature in the housing of the in-vehicle control device including the electronic component (heating element) can be kept low, and the reliability of the device is increased.

Problems, configurations, and effects other than those described above will be clarified by the following actual forms.
It is possible to provide an in-vehicle control device provided with a thermal radiation coating film that can efficiently dissipate heat generated from electronic components.

The disassembled perspective view which shows the basic composition of the actual condition form of the vehicle-mounted control apparatus which concerns on this invention. Sectional drawing of the vehicle-mounted control apparatus with which description of Example 1 is provided. Sectional drawing of the terminal part of an electronic component. Sectional drawing of the terminal part of the electronic component of Example 1. FIG. Sectional drawing of the terminal part of the electronic component of Example 2. FIG. Sectional drawing of the terminal part of the electronic component of Example 3. FIG. Sectional drawing of the terminal part of the electronic component of Example 4. FIG.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 to FIG. 7 are diagrams for explaining embodiments (Examples 1 to 4) of the in-vehicle control device 1 according to the present invention. In each figure, the same configuration part, the same function part, or the correspondence relationship The common symbols or related symbols are given to the portions in the. In order to facilitate understanding of the present invention, the thickness of each part (particularly the film thickness of the heat-radiating coating material) is exaggerated in FIGS.

FIG. 1 is an example of an exploded perspective view showing a main configuration of an in-vehicle control device 1 (ECU; Electronic Control Unit). FIG. 2 is a cross-sectional view of the in-vehicle control device 1 in FIG. As shown in FIGS. 1 and 2, the in-vehicle control device 1 includes a circuit board 12 on which electronic parts 11 such as ICs and semiconductor elements are mounted on both upper and lower (back and front) surfaces by solder, and a housing in which the circuit board 12 is accommodated. It is configured to include the body. The housing is composed of a base 13 to which the circuit board 12 is fixed and a box-like or lid-like cover 14 having an open lower surface that is assembled to the base 13 so as to cover the circuit board 12.

A connector 15 for electrically connecting the circuit board 12 and the outside is attached to one end of the circuit board 12 in the hand direction. The connector 15 includes a required number of pin terminals () and a housing provided with through holes into which the pin terminals are inserted by press fitting or the like. In this connector 15, after the pin terminals are inserted into the through holes of the housing, the lower ends (connection joints) of the pin terminals are connected and connected to the circuit board 12 by solder in a spot flow process.

The base 13 has a generally short flat plate shape as a whole so as to close the lower surface opening of the cover 14. Specifically, the base 13 includes a short plate-shaped portion, a short frame-shaped portion protruding from the short-shaped plate-shaped portion, and a seat of the circuit board 12 provided at the four corners of the short frame-shaped portion. The base part 16 used as a surface and the vehicle assembly fixing part extended in the outer periphery of the short plate-shaped part are provided. The vehicle assembly fixing unit is for assembling the in-vehicle control device 1 to the vehicle body, and is fixed by, for example, screwing bolts into a predetermined part of the vehicle body.

The base 13 and the cover 14 constituting the casing of the in-vehicle control device 1 are assembled by sandwiching the circuit board 12 to which the connector 15 is attached. More specifically, the circuit board 12 is fixed by a set screw 17 as an example of a fastening member while being sandwiched between a pedestal portion 16 provided at four corners of the base 13 and the cover 14.

The base 13 and the cover 14 are manufactured by casting, pressing or cutting using a metal material or a resin material. More specifically, it is produced by casting, pressing or cutting using a resin material such as an alloy mainly composed of aluminum, magnesium, iron, or polybutylene terephthalate.

Note that a window for the connector 15 is formed in the cover 14 so that the circuit board 12 can supply power from the outside via the connector 15, input / output to / from an external device, and transmission / reception of output signals.

For example, four electronic components 11 (three on the upper surface side and one on the lower surface side) are mounted on the circuit board 12, and the circuit wiring provided on the circuit board 12 is connected to each electronic component 11. In addition, it is also connected to the pin terminal of the connector 15.

Further, a thermal via 19 (through hole) is provided in a portion of the circuit board 12 where the electronic component 11 is mounted.

A thermal via 19 is provided below the electronic component 11 located at the center of the three electronic components 11 mounted on the upper surface side of the circuit board 12, and at the base 13 just below the thermal via 19. A short convex protrudes from the position, and a high thermal conductive layer is interposed between the lower surface of the circuit board 12 and the upper surface of the short convex portion of the base 13 so as to be in contact with both. . Here, an adhesive, grease, a heat dissipation sheet, or the like is used as the high thermal conductive layer.

The electronic component 11 (the main body portion) located on the right side of the three electronic components mounted on the upper surface side of the circuit board 12 is floated and attached from the upper surface of the circuit board 12 by the terminals of the electronic component 11. A gap is formed between the electronic component 11 and the circuit board 12.

In the vehicle-mounted control device 1 of the present embodiment, the thermal

radiation coating films

30, 31, and 32 are formed on specific parts such as the inside of the circuit board 12 and the connector 15 pins.

In this case, after the electronic component 11 and the connector 15 are mounted on the circuit board 12, the thermal

radiation coating films

30, 31, 32 are formed (applied) on the surface on which the electronic component 11 is mounted, and the base 13 and the cover After the connector 14 is formed in a predetermined size and shape, a protective coating film is formed (applied) on the pin terminal of the connector 15 in a portion between the connection joint portion on the circuit board 12 side and the connector 15 housing.

As the coating method, brush coating, spray coating, dip coating or the like is preferable, but electrostatic coating, curtain coating, electrodeposition coating, powder coating or the like may be used depending on the object to be coated. In the method of drying and forming a coating film after applying the material, a method such as natural drying, baking, or ultraviolet curing is preferably used. At this time, it is preferable that the thermal

radiation coating films

30, 31, and 32 are directly coated on the respective substrates. For example, when the thermal

radiation coating films

30, 31, 32 are formed on the circuit board 12 after the surface of the moisture-proof coating material or the like, the space between the surface of the circuit board 12 and the thermal

radiation coating films

30, 31, 32 becomes a film thickness. The moisture-proof coating film becomes a thermal resistance, the amount of heat transfer is reduced, and the heat dissipation is reduced.

FIG. 2 shows an example in which all of the thermal

radiation coating films

30, 31, 32 are formed. From the viewpoint of improving heat dissipation, it is preferable to provide a thermal radiation coating material on the plurality of surfaces described above. However, not only the entire surface of each base material but also a part of the electronic component 11, particularly an electron having a low emissivity. You may make it the structure which comprises a coating material only around the joining member for joining with the circuit boards 12, such as the terminal 13 part of the components 1, and solder. Thereby, reduction of the usage-amount of the coating material for coating can be aimed at.

Next, a specific configuration of the thermal

radiation coating films

30, 31, and 32 of this embodiment will be described. FIG. 3 is a conceptual diagram showing the structure of the terminal 13 of the electronic component provided with the thermal radiation coating film 30. A thermal radiation coating film 30 is formed on a connection material such as the circuit board 12, the terminal 13 of the electronic component, and solder. Between the two terminals 13 of an electronic component, it has the concave shape which becomes lower than the vertex part of the thermal radiation coating film 30 provided on the terminal 13. By making the thermal radiation coating film 30 into such a shape, the surface area with high emissivity can be increased, and the amount of heat transfer from the heat generating portion to the housing can be increased.

The material for forming the thermal radiation coating film 30 is not particularly limited as long as it is a material having thermal radiation, but a composite material composed of an organic resin and inorganic particles is most preferable. In this case, as the inorganic particles, conventionally known particles can be used, and are not particularly limited. However, boron nitride, aluminum nitride, aluminum oxide, magnesium oxide, titanium oxide, zirconia, iron oxide, copper oxide, nickel oxide, cobalt oxide, Preferred examples include ceramic powders such as lithium oxide, zinc oxide, magnesium hydroxide, and silicon dioxide, metal powders such as copper, nickel, iron, and silver, carbon materials, and the like. Is desirable.
In particular, since the circuit board 12 on which the electronic component 11 is mounted needs insulation, the thermal radiation coating film 30 is required to have insulation. Therefore, it is preferable to mix an insulating material such as ceramic powder in the heat radiating coating forming the heat radiating coating film 30. A conventionally known particle shape of the inorganic material can be used, and is not particularly limited, but is different from spherical shape, flake shape, needle shape, rectangular parallelepiped shape, cube shape, tetrahedron shape, hexahedron shape, polyhedron shape, cylindrical shape, tube shape, and core portion. Examples thereof include a three-dimensional needle-like structure extending in the axial direction. When two or more kinds of particles having high thermal radiation are blended, a combination that has an absorbance of 0.5 or more and does not overlap in the infrared absorption region of 1200 to 500 cm ⁻¹ is preferable. Electromagnetic waves can be emitted at a wide range of wavelengths, improving thermal radiation performance. When the inorganic particles are blended, the average particle diameter is not particularly limited, but is 0.001 to 200 μm. If the average particle diameter is too large (exceeding 200 μm), the thickness of the coating film is increased and the thermal radiation is reduced, and the strength of the coating film and the adhesion strength and adhesion of the coated body may be reduced. Moreover, when an average particle diameter is too small (less than 0.001 micrometer), there exists a dislike that the interface of particle | grains and a binder will increase and heat radiation performance will fall.

A conventionally well-known thing can be used as said organic resin, Although it does not specifically limit, A synthetic resin and water-system emulsion resin are mentioned as an example. Synthetic resins include phenolic resins, alkyd resins, melamine urea resins, epoxy resins, polyurethane resins, vinyl acetate resins, acrylic resins, chlorinated rubber resins, vinyl chloride resins, fluororesins, etc. An acrylic resin. Examples of the water-based emulsion include silicon acrylic emulsion, urethane emulsion, and acrylic emulsion. Also, the organic resin is preferably not less than 1.1 × ¹⁰ 6 Pa loss modulus at 125 ℃ 1.0 × ¹⁰ 5 Pa or more, or storage modulus. This is because if the circuit board 12 on which the electronic component 11 is mounted is subjected to the same thermal shock as when the automobile is operated, for example, −40 ° C. and 125 ° C., cracks occur in the fillet portion of the connecting material such as solder. In the high temperature region 125 ° C., the thermal radiation coating material is melted and prevented from entering the cracked portion of the connecting material, and the reliability is improved.

Examples of the solvent include water and organic solvents, and are not particularly limited. The selection of the solvent is optimally determined depending on the combination of the solvent and other materials such as a filler and a dispersing material, and it is desirable to select a suitable solvent. Examples of the organic solvent include ketone-based, alcohol-based and aromatic-based organic solvents. Specific examples include acetone, methyl ethyl ketone, cyclohexene, ethylene glycol, propylene glycol, methyl alcohol, isopropyl alcohol, butanol, benzene, toluene, xylene, ethyl acetate, and butyl acetate. These may be used alone or in combination.

In addition to the above components, the thermal radiation coating material may further contain components as necessary. Examples of the component include a solvent, a film forming aid, a plasticizer, a pigment, a silane coupling agent, and a viscosity modifier. As said component, a conventional thing can be used and it does not specifically limit.

The application method of the thermal radiation coating material is not particularly limited, and can be selected from commonly used application methods according to the purpose. Specific examples include brush coating, spray coating, roll coater coating, and immersion coating. In the method of drying and forming a coating film after applying the heat radiation material, methods such as natural drying, baking, and ultraviolet curing can be used, which are selected depending on the properties of the paint.

Further, the average film thickness of the flat portion of the thermal radiation coating film 30 on which the electronic component 11 is not mounted can be selected according to the purpose, but is preferably 200 μm or less, and preferably 1 μm to 200 μm. Is more preferable. When a coating film is 200 micrometers or more, a coating film becomes a heat insulation layer and there exists a possibility that heat dissipation may fall. On the other hand, when the thickness is 1 μm or less, the heat dissipation effect may not be sufficiently exhibited. Further, from the viewpoint of thermal radiation, the thermal radiation coating film 30 preferably has a thermal emissivity with respect to each wavelength in the wavelength region of 2.5 μm to 20 μm of 0.8 or more, and more preferably closer to 1.

For thermal radiation, a binder resin is specified by an analysis method such as IR (infrared spectroscopy) or GCMS (gas chromatographic analysis), and the cross section of the thermal radiation coating film 30 is SEM-EDX (scanning electron microscope-energy dispersion type). Particles are identified by elemental analysis such as X-ray analysis), and each is blended, and the emissivity of the formed film is measured.

The emissivity measurement method is as follows. The prepared material was applied to an aluminum plate having a size of 100 mm × 100 mm and a thickness of 1 mm by changing the film thickness using an applicator, and the cured sample was subjected to Kyoto Electronics D and S AERD. The emissivity was measured at room temperature.

The hardness of the thermal radiation coating film 30 is measured by applying the prepared material to an aluminum plate having a size of 100 mm × 100 mm and a thickness of 1 mm using an applicator at a film thickness of 30 μm, and then thinning the cured sample at 27 ° C. The indentation hardness was measured using a hardness meter (nanoindenter).

The viscosity measurement method of the thermal radiation coating material was measured at room temperature using a rotary viscometer.

Next, an example of an assembly process of the in-vehicle control device 1 will be described.
The electronic component 11 is mounted on the circuit board 12 by a joining member such as solder. After the process of assembling the connector 15 pins to the connector 15 housing, the connector 15 pins and the circuit board 12 are joined by solder in a spot flow process. After the electronic component 11 and the connector 15 are mounted on the circuit board 12, a thermal radiation coating material is applied, and the thermal radiation coating film 30 is provided. As an application method, application by brush coating, spray coating, dip coating or the like is preferable, but electrostatic coating, curtain coating, electrodeposition coating, powder coating, or the like may be used depending on the object to be applied. As a method for drying and forming a coating film after applying the thermal radiation coating material, a method such as natural drying or baking is preferably used.

The cover 14 is manufactured by casting, pressing or cutting using a resin material such as an alloy mainly composed of aluminum, magnesium, iron, or polybutylene terephthalate. The shape of the cover 14 is open at the bottom and is provided with a connector 15 window.

The base 13 is manufactured by casting, pressing or cutting using an alloy mainly composed of aluminum, magnesium, iron, or a resin such as polybutylene terephthalate. The shape of the base 13 is formed on a substantially flat plate so as to close the bottom opening of the cover 14.

The film thickness of the thermal radiation coating film 30 is about 1 μm to 200 μm, preferably 10 μm to 150 μm, in a flat portion of the circuit board 12 where the electronic component 11 is not mounted. When the film thickness is too thicker than 200 μm, the absorbed heat is cut off, and when it is thinner than 1 μm, the heat radiation performance is lowered.

The film thickness of the thermal radiation coating film 30 covering the terminals 13 of the electronic component is 10 μm to 200 μm, preferably 30 μm to 150 μm. When the film thickness is more than 150 μm, the absorbed heat is blocked, and when it is less than 10 μm, the heat radiation performance is deteriorated. Therefore, the amount of heat transfer from the high temperature part such as a heating element to the outside of the housing is reduced. The film thickness of the thermal radiation coating film 30 covering the central part between the two terminals 13 of the electronic component is about 1 μm to 200 μm, and preferably the film thickness is 70 μm to 150 μm. In particular, the circuit board 12 impregnated with a resin material such as a glass epoxy substrate has an emissivity of 0.6 or more, and thus the emissivity is improved by setting the thickness of the thermal radiation coating film 30 to 70 μm or more. The amount of heat transfer from the high temperature part such as a heating element to the outside of the housing increases.

Also, in the terminal 13 portion of the electronic component, it is preferable to form a concave shape between the two terminals 13 that is lower than the apex portion of the thermal radiation coating film 30 provided on the terminal 13. As a result, the surface area of the thermal radiation coating film 30 having a high emissivity is increased, so that the amount of heat transfer from a high temperature part such as a heating element to the outside of the housing is increased.

Hereinafter, a detailed description will be given using examples. However, the present invention is not limited to the contents described in the following examples.

In Example 1, as shown in FIG. 2, a radioactive coating film is formed on the front and back surfaces of the circuit board 12 on which the electronic component 11 is mounted.

As shown in FIG. 4, the thermal radiation coating film 30 on the terminal 13 of the electronic component is formed with a film thickness of 10 μm, and the film thickness in the center between the two terminals 13 is 70 μm or less. In addition, a concave shape is formed between the two terminals 13 that is lower than the apex portion of the thermal radiation coating film 30 provided on the terminals 13. Thereby, the emissivity is increased on the terminal 13 of the electronic component 11 and the surface area is increased, so that the heat dissipation is improved.

In Example 2, as shown in FIG. 5, the thermal radiation coating film 30 on the terminal 13 of the electronic component is formed with a film thickness of 10 μm, and the film thickness of the central part between the two terminals 13 is 70 μm or more. In addition, a concave shape is formed between the two terminals 13 that is lower than the apex portion of the thermal radiation coating film 30 provided on the terminals 13. As a result, the emissivity is increased between the terminals 13 and the terminals 13 of the electronic component and the surface area is increased, so that heat dissipation is improved.

In Example 3, as shown in FIG. 6, the thermal radiation coating film 30 on the terminal 13 of the electronic component is formed with a film thickness of 10 μm to 150 μm, and the film thickness of the central part between the two terminals 13 is 70 μm or less. . In addition, a concave shape is formed between the two terminals 13 that is lower than the apex portion of the thermal radiation coating film 30 provided on the terminals 13. As a result, the emissivity is increased on the terminal 13 of the electronic component and the surface area is increased, so that heat dissipation is improved.

In Example 4, as shown in FIG. 7, the thermal radiation coating film 30 on the terminal 13 of the electronic component is formed with a film thickness of 10 μm to 150 μm, and the film thickness of the central part between the two terminals 13 is 70 μm or more. . In addition, a concave shape is formed between the two terminals 13 that is lower than the apex portion of the thermal radiation coating film 30 provided on the terminals 13. As a result, the emissivity is increased between the terminals 13 and the terminals 13 of the electronic component and the surface area is increased, so that heat dissipation is improved.

(Evaluation materials)
(Comparative material)
Resin A: Viscosity 60 mPa · s

(Implementation material)
-Thermosetting resin + nanosilica (particle size 12 nm) 5 W% content: viscosity 90 mPa · s

(Evaluation methods)
The heat dissipation evaluation method is as follows.

Surface heating element polyimide heater FL-HEATNo. 6 (Shinwa Measurement Co., Ltd.) is sandwiched between aluminum plates (50 mm × 80 mm, t: 2 mm). A thermocouple is bonded to the surface of the aluminum plate with aluminum plate solder. The prepared sample was applied to the surface of the aluminum plate, dried by heating at 60 ° C. for 30 minutes, and applied with changing the film thickness. The sample was placed in the center of a thermostat set at 25 ° C., 6 W was applied to the heater, and the temperature change on the aluminum plate surface was measured. Since the heater generates a certain amount of heat, the higher the heat radiation effect of the heat radiation material, the lower the heater temperature or the aluminum plate surface temperature. That is, it can be said that the heat dissipation effect is higher as the heater temperature or the aluminum plate surface temperature is lower.

Table 1 shows the film thickness and emissivity of the comparative material and the implementation material. The emissivity with a thickness of 0 μm indicates the emissivity of the aluminum plate. From the results shown in Table 1, the emissivity can be further increased by increasing the thickness of the material of this embodiment.

Table 2 shows the film thickness and heat dissipation effect of the comparative material and the implementation material. “-” Indicates that measurement cannot be performed because the coating film cannot be thickened on the terminal 13 of the electronic component. From the results in Table 2, heat dissipation is improved by forming the material of this embodiment into a pressure film.

Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above-described embodiments, and various designs can be made without departing from the spirit of the present invention described in the claims. It can be changed. For example, the above-described embodiment has been described in detail for easy understanding of the present invention, and is not necessarily limited to one having all the configurations described. Further, a part of the configuration of an embodiment can be replaced with the configuration of another embodiment, and the configuration of another embodiment can be added to the configuration of an embodiment. Furthermore, it is possible to add, delete, and replace other configurations for a part of the configuration of each embodiment.

DESCRIPTION OF SYMBOLS 1 In-vehicle control apparatus 11 Electronic component 12 Circuit board 13 Base 14 Cover 15 Connector 16 Base part 17 Screw 18 Vehicle mounting fixing part 19 Thermal via 22 Connection member 23

Terminal

30, 31, 32 of electronic parts Thermal radiation coating film

Claims

A circuit board;
Electronic components mounted on the circuit board;
A connection member for connecting the terminal of the electronic component and the circuit board;
In an electronic control device having a thermal radiation coating film covering the circuit board and the terminal,
An electronic control device characterized in that the thermal radiation coating film covering the terminals has a thickness of 10 μm or more.
A circuit board;
Electronic components mounted on the circuit board;
A connection member for connecting the terminal of the electronic component and the circuit board;
In an electronic control device having a thermal radiation coating film covering the circuit board and the terminal,
An electronic control device characterized in that the thermal radiation coating film covering the terminals has a thickness of 30 μm or more.
The electronic control device according to claim 1 or 2,
The electronic control apparatus according to claim 1, wherein the thermal radiation coating film has a concave shape between the two terminals, which is lower than an apex of the thermal radiation coating film provided on the terminal.
In the vehicle-mounted control apparatus as described in any one of Claim 1 to 3,
The thermal radiation coating film has a central portion between the two terminals.
A vehicle-mounted control device, wherein the thickness of the thermal radiation coating film is 70 μm or more.
In the vehicle-mounted control apparatus as described in any one of Claim 1 to 4,
The electronic control device according to claim 1, wherein the thermal radiation coating film has a thickness of 150 μm or less.
In the vehicle-mounted control apparatus as described in any one of Claim 1 to 5,
An electronic control device, wherein the thermal radiation coating film has a hardness of 5.5 N / mm 2 or more.
The thermal radiation coating material for forming the thermal radiation coating film according to any one of claims 1 to 6,
A vehicle-mounted control device characterized in that the viscosity upon application to a circuit board is 90 mPa · s.