Assembly for a computing unit

Abstract

The invention relates to an assembly (110, 110') for a computing unit (100), in particular for a computing unit for a vehicle, wherein the computing unit (100) comprises a circuit carrier (120) and an electrical component (121, 121'), wherein the electrical component (121, 121') is connected to the circuit carrier (120) at a predetermined component position, wherein the assembly (110, 110') comprises a housing element (111, 111') and a cooling element (112, 112'), wherein the cooling element (112, 112') is attached to the housing element (111, 111') at a predetermined position depending on the predetermined component position, and wherein the cooling element (111, 111') is configured to be thermally coupled to the electrical component (121, 121'), so that a heat path is generated from the electrical component (121, 121') via the cooling element (112, 112') to the housing element (111, 111').

Description

The present invention relates to a module for a computing unit and a computing unit having such a module, and to a method for producing a module and to a method for producing a computing unit.BACKGROUND OF THE INVENTIONIn computing units which have electrical or electronic components with high power losses, it may be important to be able to dissipate waste heat from such components. For this purpose, the electrical components can be thermally connected to a housing of the computing unit, for example by connecting the components to the housing via a layer of a heat-conducting material or a thermal interface material (TIM). Such electrical components can be designed, for example, as semiconductor switching elements, for example as transistors such as FETs, MOSFET, IGBT, etc., which are often used in the (motor) vehicle sector. A corresponding computing unit can be, for example, a control unit of a (motor) vehicle.Disclosure of the InventionAccording to the invention, a module for a computing unit and a computing unit having such a module, and a method for producing a module, and a method for producing a computing unit, a method having the features of the independent patent claims, are proposed.Advantageous embodiments are the subject matter of the dependent claims and of the following description.The assembly is provided for mounting in a computing unit, in particular in a computing unit for a (motor) vehicle, e.g. in a control unit. This computing unit has a circuit carrier, in particular a printed circuit board (PCB), and an electrical or electronic component, wherein this electrical component is connected to the circuit carrier or fastened to the circuit carrier at a predefined component position. The component is, for example, a power semiconductor or an integrated circuit (IC).The assembly includes a housing member and a cooling member. The cooling element is fastened to the housing element at a predefined position depending on the predefined component position, in particular by means of a materially bonded connection, e.g. a soldered connection, in particular a reflow soldered connection. The cooling element is in particular a metallic cooling element, which can comprise, for example, aluminum and / or iron and / or copper.The housing element can serve, for example, as a housing cover or as a housing base of a housing of the computing unit. This is in particular a metallic housing element, which may have, for example, aluminum and / or iron and / or copper. The cooling element is configured to be thermally coupled or brought into thermal connection with the electrical component, such that a heat path or a heat conducting path or a thermal path is generated from the electrical component via the cooling element to the housing element.The position of the cooling element is predefined in particular as a function of the component position in such a way that, in an assembled state of the computing unit, when the housing element is connected to the circuit carrier, the cooling element is thermally coupled to the electrical component. During operation of the computing unit, waste heat can be dissipated from the electrical component to the housing element via the cooling element.The computing unit can also have a plurality of electrical components, each of these electrical components being connected to the circuit carrier in each case at a predefined component position. The assembly has in particular a cooling element for each of these electrical components, wherein each of these cooling elements is configured to be thermally coupled to the respective electrical component.The invention further relates to a method for producing the assembly. In the course of the method, the housing element and the cooling element are provided. The cooling element is fastened to the housing element at the predetermined position depending on the predetermined component position, expediently by means of a materially bonded connection such as a (reflow) soldered connection.For this purpose, a solder paste can be applied to the provided housing element at the corresponding position. The cooling element (or a plurality of cooling element parts) can then be arranged on the solder paste. The housing element and the cooling element can now be connected by means of the solder paste in a materially integral manner, for example by heating the housing element in a furnace, for example in a so-called reflow furnace.The invention further relates to a method for producing the computing unit. In the course of the method, the assembly with the housing element and the cooling element is produced. Furthermore, the electrical component is connected to the circuit carrier at the predetermined component position, for example by a soldered connection. The assembly is then connected to the circuit carrier.The invention provides with the assembly a modular component or a modular housing component and a separate structural unit for the computing unit. In particular, the housing element with the cooling element fastened thereon can be provided as a completely manufactured component for an assembly process of the computing unit and can be assembled with the further components of the computing unit in a structurally simple and low-complexity manner. Expediently, the electrical component can be thermally connected to the housing element automatically in a simple manner during such an assembly, so that waste heat can be effectively dissipated via the housing element during operation of the electrical component. In particular, the assembly can be adapted flexibly and individually to conditions and dimensions of the computing unit, in particular to the position and size of the electrical component. For this purpose, the position and / or dimensions of the cooling element can be adapted to the circumstances of the computing unit.If individual components of a computing unit are to be newly developed or newly designed, for example if a new layout of a circuit carrier is to be developed, this can often result in other components also having to be changed and often having to be completely newly designed. For example, a new layout of the circuit carrier can result in electrical components to be arranged thereon no longer being able to be thermally connected to an existing housing for the purpose of removing waste heat, so that a completely new design of the housing is required. Such a new development of a housing can, however, be associated with high outlay and high costs and with long development and production times.In contrast, the assembly can be adapted in a cost-effective and simple manner to newly developed or newly designed components of the computing unit. Particularly expediently, no complicated changes to the housing element itself are required for this purpose and it is in particular not necessary to develop a new housing or a new housing element. In particular, the assembly can be adapted to modified components of the computing unit only by low-complexity changes of the cooling element, in particular by adapting the predefined position of the cooling element and / or by adapting the specific dimensions of the cooling element.If, for example, the position or orientation of the electrical component within the computing unit changes as a result of a new development of individual components of the computing unit, for example as a result of a new layout of the circuit carrier, the assembly can be adapted to these new conditions in the computing unit particularly expediently by low-complexity adaptation of the predefined position of the cooling element, and furthermore, if appropriate, of the shape or dimensions of the cooling element, with the result that the electrical component can continue to be thermally connected to the housing element in a simple manner for cooling purposes.In particular, this also results in the advantage of forming a housing family comprising at least two housing variants. The individual housing variants correspond in each case to a previously described assembly comprising a housing element and a cooling element, wherein the cooling element is fastened to the housing element at a predefined position depending on the predefined component position. Both housing variants further comprise an identical housing element in the form of a basic housing. The at least two housing variants differ in a variant-specific manner in that a position and / or a size and / or shape of at least one cooling element connected to the basic housing is different. The distinction takes into account the need to adapt a heat path of a populated circuit carrier to be accommodated in the basic housing in such a way that the at least one cooling element is fastened to the basic housing at a predefined position depending on the predefined component position of a component that emits heat assigned to the cooling element on the accommodated circuit carrier, in particular by means of a material bond, for example a solder connection. It is thus also possible in the simplest way to configure a family of computing units comprising at least two variants of computing units. The at least two variants of computing units differ at least in that they have at least one previously described other housing variant. This can be due, for example, to the fact that the at least two variants of computing units also have different populated circuit carriers and there is therefore the need for at least one cooling element to be adapted in terms of its size and / or its shape and / or to be fastened at another point of the otherwise same basic housing. The adaptation and / or fastening position therefore takes place depending on the type of a heat-emitting component and / or its position on the variant-specific circuit carrier which is assigned to the corresponding variant of a computing unit. In this way, cost-effective scaling effects and / or customer-specific designs of computing units result, utilizing the basic housing as a common component.According to one configuration, dimensions of the cooling element, in particular a length and / or a width and / or a height, are or are predefined as a function of corresponding dimensions of the electrical component. The cooling element can thus be individually adapted to the position and the size of the respective electrical component, so that the heat path from the electrical component via the cooling element to the housing element can be effectively generated.According to one embodiment, the cooling element has a number of identical cooling element parts. For example, a plurality of different basic shapes of cooling element parts can be stored and the respectively planned cooling element is assembled from these cooling element parts in modular fashion. For example, (small) cuboids with different dimensions can be stored as cooling element parts. To minimize the diversity of components, it is possible, for example, to store cuboids having the same base area but different heights as cooling element parts, wherein then usually a specific height also fits particularly well for a specific electrical component.According to one configuration, the cooling element is fastened to the housing element at the predefined position in such a way that, viewed in a direction or projection perpendicular to the circuit carrier, it is at least partially congruent, in particular arranged completely congruent or aligned with respect to one another. The predefined position of the cooling element is thus predefined in particular such that the cooling element is arranged as close as possible relative to the electrical component in the mounted state of the computing unit. The length and width of the cooling element can in this case correspond in particular to the respective length or width of the electrical component or even exceed it.According to one configuration, the electrical component is arranged in the computing unit on a side of the circuit carrier facing the cooling element. A layer of a thermal interface material (TIM) is expediently arranged between the electrical component and the cooling element in order to thermally couple the cooling element to the electrical component. In particular, the electrical component is thus arranged directly adjacent to the cooling element and is connected directly to the cooling element via the TIM layer.Alternatively, according to one configuration, the electrical component is arranged on a side of the circuit carrier facing away from the cooling element. The circuit carrier is arranged in this case between the electrical component and the cooling element. In this case, a layer of a heat-conducting material is arranged between the circuit carrier and the cooling body in order to thermally couple the cooling element to the electrical component. In this case, the heat path is generated, in particular starting from the electrical component, via the circuit carrier, via the TIM layer and via the cooling element to the housing element.According to one configuration, the computing unit furthermore has a second housing element, wherein the housing element of the assembly is connected to the second housing element, for example by means of screw connections. In particular, the housing element of the assembly and the second housing element together can form a complete housing of the computing unit.According to one configuration, alternatively to a mere second housing element, a second assembly of a second housing element and a second cooling element can also be used. In this case, for example, an electrical component can be heat-removed from two sides, or the computing unit can have a second electrical component, wherein this second electrical component is connected to the circuit carrier at a second predefined component position, for example via a cohesive connection. The second assembly is manufactured as explained above according to an embodiment of the invention. The second cooling element is connected to the second housing element at a second predefined position depending on the first or second predefined component position, in particular via a cohesive connection such as a (reflow) soldered connection. The second cooling element is configured to be thermally coupled to the first or second electrical component, such that a heat path is generated from the first or second electrical component via the second cooling element to the second housing element. The housing element of the assembly and the second housing element of the second assembly are connected to one another and together form, in particular, a complete housing of the computing unit.The second cooling element is also connected to the second housing element in particular in such a way that, in the assembled state of the computing unit, the second cooling element and the first or second electrical component are arranged at least partially congruently, in particular completely congruently, as viewed in a direction perpendicular to the circuit carrier. The second electrical component can also be arranged on a side of the circuit carrier facing or facing away from the second cooling element. Depending on this arrangement, a corresponding TIM layer is expediently provided between the second electrical component and the second cooling element or between the circuit carrier and the second cooling element, in order to generate the respective heat path.The invention is particularly suitable for use in the (motor) vehicle sector. The computing unit can be designed in particular as a control unit in a (motor) vehicle. Such a control device can have a large number of electrical components, for example semiconductor switching elements, for example transistors such as FETs, MOSFET, IGBT, etc. The control device can be used in particular for safe operation and for controlling the vehicle, for example in the course of engine control or in the course of driving assistance functions, etc.Further advantages and embodiments of the invention will become apparent from the description and the accompanying drawing.The invention is schematically illustrated in the drawing on the basis of exemplary embodiments and is described below with reference to the drawing.Brief Description of the DrawingsFIG. 1 shows an embodiment of a computing unit according to the invention with an embodiment of an assembly according to the invention in a schematic sectional view. FIG. 2 shows elements of an embodiment of an assembly according to the invention in different views a) to f) in the course of an embodiment of a method according to the invention.Embodiment(s) of the InventionFIG. 1 shows an embodiment of a computing unit according to the invention in a schematic sectional view and is denoted by 100. The arithmetic unit 100 is provided, for example, as a control unit for a (motor) vehicle.This control device 100 has a circuit carrier, for example a printed circuit board 120, and a multiplicity of electrical or electronic components 121, 121', for example semiconductor switching elements, for example MOSFETs, integrated circuits (ICs), etc. Each of these components 121, 121' is in each case connected to the printed circuit board 120 at respective component positions, for example by means of a soldered connection 122, 122'.Since the components 121, 121' can have a high power loss during operation, the components 121, 121' are intended to be thermally connected to a housing of the control unit 100 for dissipation of heat or for heat dissipation.For this purpose, the control device 100 has a housing with two housing components 110, 110', wherein each of these housing components 110, 110' can be provided in each case as an embodiment of a subassembly according to the invention.For example, a first assembly 110 forms a housing base. This assembly 110 comprises a housing element 111 and a cooling element 112. The cooling element 112 is fastened to the housing element 111 at a predetermined position depending on the component position of the component 121, e.g. by a soldered connection 113, so that the cooling element 111 is thermally coupled to the component 121 and a heat path is generated from the component 121 via the cooling element 112 to the housing element 111.The dimensions of the cooling element 111 are predetermined depending on corresponding dimensions of the MOST 121. In particular, for this purpose, the cooling element 111 can be composed of a multiplicity of cooling element parts, in particular identical cooling element parts, small cuboid cooling element parts being shown, for example, in the figure. Thus, different sizes and shapes of cooling elements can be realized in a simple manner. The cooling element 112 is fastened to the housing element 111 at the predetermined position in such a way that the cooling element 112 and the component 121 are arranged congruently, as viewed in a direction perpendicular to the printed circuit board 120.The component 121 is arranged, for example, on a side of the printed circuit board 120 facing away from the cooling element 112. A layer 123 of a thermal interface material (TIM) is disposed between the circuit board 120 and the cooling element 112 to thermally couple the cooling element 112 to the device 121. In this case, the heat path is generated from the component 121, via the printed circuit board 120, via the TIM layer 123 and via the cooling element 112 to the housing element 111.A second assembly 110' forms, for example, a housing cover. This second assembly 110' also has a housing element 111' and a cooling element 112', wherein this cooling element 112' is fastened to the housing element 111' at a predetermined position depending on the component position of the component 121', e.g. by a soldered connection 113', so that the cooling element 111' is thermally coupled to the component 121' and a heat path is generated from the component 121' via the cooling element 112' to the housing element 111'.The dimensions of the cooling element 111' are predefined as a function of corresponding dimensions of the component 121', and the cooling element 111' is fastened to the housing element 111' in such a way that this cooling element 111' and the MOSFET 121' are arranged congruently, as viewed in a direction perpendicular to the printed circuit board 120.The component 121' is arranged on a side of the circuit board 120 facing the cooling element 112', and a layer 123' of a heat conducting material is arranged between the component 121' and the cooling element 112' in order to thermally couple the cooling element 112' to the component 121'. In this case, the heat path is generated from the component 121' via the TIM layer 123' and via the cooling element 112' to the housing element 111'.The invention provides with the assembly 110, 110' a modular component or a separate structural unit for the control unit 100, which can be mounted with the further components of the control unit 100 in a structurally simple and low-complexity manner. The assembly 110, 110' can be adapted flexibly and individually to conditions and dimensions of the control unit 100, in particular by adapting the position and / or the dimensions of the cooling element 112, 112' to the circumstances within the control unit 100. Particularly expediently, no complicated changes are required for this purpose on the housing element 111, 111' itself and it is in particular not necessary to develop a new housing or a new housing element. Furthermore, the assembly can be produced cost-effectively and in a low-complexity manner, as will be explained below with reference to FIGS. 2 ato 2 f.FIGS. 2 ato 2 feach show elements of an embodiment of an assembly 210 according to the invention during different steps of a production process in the course of an embodiment of a method according to the invention.As shown in FIGS. 2 aand 2 b, a housing element 211 is first provided. This is in particular a metallic housing element, which may have, for example, aluminum and / or iron and / or copper. FIG. 2 ashows the housing element 211 in a schematic sectional view. FIG. 2 bshows the housing element 211 in a schematic, perspective view.As shown in FIGS. 2 cand 2 d, a solder paste 213 is applied to the housing element 211 at different predetermined positions, respectively. The housing element 211 with the applied solder paste 213 is illustrated in FIG. 2 cin a schematic view and in FIG. 2 din a schematic, perspective sectional view. These positions are respectively predefined as a function of a component position of a respective MOSFET which is intended to be thermally connected to the housing element 211.As shown in FIGS. 2 eand 2 f, a cooling element 212 or cooling element parts are applied to this solder paste 213 in each case at the various predefined positions. The cooling element or elements 212 are also in particular metallic cooling elements which comprise, for example, aluminum and / or iron and / or copper.The housing element 211 with the cooling element 212 applied is shown in FIG. 2 ein a schematic sectional view and in FIG. 2 fin a schematic perspective view. The housing element 211 with the cooling elements 212 can now be heated in a furnace, for example in a reflow furnace, so that the cooling elements 212 are fastened to the housing element 211 in a materially bonded manner via a soldered connection. The assembly 210 can now be used for connection to further components of the respective control unit.

Claims

Assembly (110, 110', 210) for a computing unit (100), in particular for a computing unit for a vehicle, wherein the computing unit (100) has a circuit carrier (120) and an electrical component (121, 121'), wherein the electrical component (121, 121') is connected to the circuit carrier (120) at a predetermined component position, wherein the assembly (110, 110', 210) has a housing element (111, 111', 211) and a cooling element (112, 112', 212), wherein the cooling element (112, 112', 212) is fastened to the housing element (111, 111', 211) at a predetermined position depending on the predetermined component position and wherein the cooling element (111, 111', 211) is configured to be thermally coupled to the electrical component (121, 121'), such that a heat path from the electrical component (121, 121') via the cooling element (112, 112, 112', 212) to the housing member (111, 111', 211).Assembly (110, 110', 210) according to claim 1, wherein dimensions of the cooling element (112, 112', 212), in particular a length and / or a width and / or a height, are predefined depending on dimensions of the electrical component (121, 121').The assembly (110, 110', 210) of claim 1 or 2, wherein the cooling element (111, 111', 211) comprises a number of equal cooling element parts.Assembly according to one of the preceding claims, wherein the cooling element (111, 111', 211) is fastened to the housing element (111, 111', 211) in a materially integral manner.Computing unit (100), in particular computing unit for a vehicle, having a circuit carrier (120) and an electrical component (121, 121'), wherein the electrical component (121, 121') is connected to the circuit carrier (120) at a predefined component position, and a subassembly (110, 110', 210) having a housing element (111, 111', 211) and a cooling element (112, 112', 212) according to one of the preceding claims.Computing unit (100) according to Claim 5, wherein the electrical component (121') is arranged on a side of the circuit carrier (120) facing the cooling element (111'), and wherein a layer (123') made of a heat-conducting material is arranged between the electrical component (121') and the cooling element (112') in order to thermally couple the cooling element (112') to the electrical component (121'), or wherein the electrical component (121) is arranged on a side of the circuit carrier (120) facing away from the cooling element (112), wherein a layer (123) made of a heat-conducting material is arranged between the circuit carrier (120) and the cooling element (112) in order to thermally couple the cooling element (112) to the electrical component (121).The computing unit (100) of claim 5 or 6, further comprising a second housing element, wherein the housing element (111, 111', 211) of the assembly (110, 110', 210) is connected to the second housing element.The computing unit (110, 110', 210) according to claim 5 or 6, further comprising a second assembly (110, 110', 210) comprising a second housing element (111, 111', 211) and a second cooling element (110, 110', 210) according to any one of claims 1 to 4, wherein the second cooling element (112, 112', 212) is attached to the second housing element (111, 111', 211) at a second predetermined position depending on the first predetermined component position, wherein the second cooling element (112, 112', 212) is configured to be thermally coupled to the electrical component (121, 121') such that a heat path is generated from the electrical component (121, 121') via the second cooling element (112, 112', 212) to the second housing element (111, 111', 211), wherein the housing element (111, 111', 211) of the assembly (110, 110', 210) and the second housing element (111, 111', 211) of the second assembly (110, 110', 210) are connected to one another.The computing unit (110, 110', 210) according to claim 5 or 6, further comprising a second electrical component (121, 121'), wherein the second electrical component (121, 121') is connected to the circuit carrier (120) at a second predetermined component position, and a second assembly (110, 110', 210) comprising a second housing element (111, 111', 211) and a second cooling element (110, 110', 210) according to any one of claims 1 to 4, wherein the second cooling element (112, 112', 212) is fastened to the second housing element (111, 111', 211) at a second predetermined position depending on the second predetermined component position, wherein the second cooling element (112, 112', 212) is configured to be thermally coupled to the second electrical component (121, 121') such that a heat path from the second electrical component (121, 121') via the second cooling element (112, 112', 112', 212) to the second housing element (111, 111', 211), wherein the housing element (111, 111', 211) of the assembly (110, 110', 210) and the second housing element (111, 111', 211) of the second assembly (110, 110', 210) are connected to each other.Method for producing a module (110, 110', 210) for a computing unit (100), wherein the computing unit (100) has a circuit carrier (120) and an electrical component (121, 121') arranged on the circuit carrier (120), wherein the electrical component (121, 121') is connected to the circuit carrier (120) at a predetermined component position, comprising the steps: providing a housing element (111, 111', 211); providing a cooling element (112, 112', 212); and fixing the cooling element (112, 112', 212) to the housing element (111, 111', 211) at a predetermined position depending on the predetermined component position, wherein the cooling element (112, 112', 212) is configured to be thermally coupled to the electrical component (121, 121'), such that a heat path is generated from the electrical component (121, 121') via the cooling element (112, 112', 212) to the housing element (111, 111', 211).Method according to claim 10, further comprising: presetting dimensions of the cooling element (112, 112', 212), in particular a length and / or a width and / or a height, depending on dimensions of the electrical component (121, 121').The method of claim 10 or 11, further comprising: providing the cooling element (112, 112', 212) by assembling a plurality of cooling element parts.Method for producing a computing unit, comprising the steps of: producing a module (110, 110', 210) having a housing element (111, 111', 211) and a cooling element (112, 112', 212) by a method according to one of Claims 10 to 12; connecting an electrical component (121, 121') to a circuit carrier (120) at a predetermined component position; connecting the module (110, 110', 210) to the circuit carrier (120).The method of claim 13, further comprising: thermally coupling the cooling element (112, 112', 212) to the electrical device (121, 121') such that a thermal path is generated from the electrical device (121, 121') via the cooling element (112, 112', 212) to the housing element (111, 111', 211).The method of claim 13 or 14, further comprising: arranging the electrical component (121') on a side of the circuit carrier (120) facing the cooling element (112') and arranging a layer (123') of a heat conducting material between the electrical component (121') and the cooling element (112') to thermally couple the cooling element (112') to the electrical component (121'); or arranging the electrical component (121) on a side of the circuit carrier (120) facing away from the cooling element (112) and arranging a layer (123) of a heat conducting material between the circuit carrier (120) and the cooling element (112) to thermally couple the cooling element (112) to the electrical component (121).The method of any one of claims 13 to 15, further comprising: providing a second housing element or providing a second assembly (110, 110', 210) having a second housing element (111, 111', 211) and a second cooling element (112, 112', 212) by a method according to any one of claims 10 to 12; and connecting the housing element (111, 111', 211) to the second housing element.

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