Cooling device for cooling elements of a circuit board

Abstract

A cooling device for cooling electronic components is provided, the electronic components including a primary electronic component of a circuit board and one or more secondary electronic components. The cooling device includes a first cooling component. The first cooling component includes a first cooling member configured to contact a surface of the primary electronic component. The first cooling member is configured to be in fluid communication to enable effective convective cooling of the surface of the primary electronic component. The cooling device further includes a second cooling component. The second cooling component includes a second cooling member configured to contact a respective hot surface of the one or more secondary electronic components to enable effective conductive cooling of the one or more secondary electronic components. The second cooling member is thermally coupled to the first cooling member.

Description

Technical Field

[0001] This invention relates to cooling of electronic components on a shared circuit board. More specifically, this invention relates to a cooling device for cooling a multi-chip module comprising primary electronic components and one or more secondary electronic components. Background Technology

[0002] Electronic components generate heat when performing electrical services. Many computing systems integrate numerous discrete electronic components on a substrate of shared circuitry (often called cards or boards). Each discrete component performs a specific task with varying complexity. Some of these computing components, especially those that are relatively high-powered and computationally expensive, such as the central processing unit (CPU) and graphics processing unit (GPU), are capable of generating significant amounts of heat during operation. Therefore, providing effective cooling to remove the generated waste heat and ensure that the electronic components remain within their permissible operating temperature range is crucial.

[0003] Various types of computer coolers have been developed based on different cooling mechanisms. Generally, existing coolers are either air-based or liquid-based. Of the two, liquid-based cooling has advantages over air-based cooling due to its superior thermophysical properties; for example, liquid-based cooling has higher thermal conductivity, density, and specific heat capacity compared to air-based cooling. Therefore, liquid-based cooling offers higher cooling efficiency, consumes less power, and thus has a smaller environmental coverage area, making it a more sustainable cooling solution.

[0004] While processing electronics such as CPUs and GPUs are typically the primary sources of waste heat, secondary electronics still generate significant amounts of heat during operation. If not cooled, this heat from these auxiliary electronics not only affects the operation of the auxiliary electronics themselves but also adversely impacts the performance of the primary processing electronics, the long-term reliability of integrated circuit boards, and increases in ambient temperature.

[0005] Therefore, it is necessary not only to cool the main electronic components, but also to cool the auxiliary electronic components to ensure the correct and reliable operation of the electronic device.

[0006] For example, a graphics card is a standalone plug-in board that contains a high-power main processing unit, the GPU, and a series of low-power secondary electronic components to support the GPU and graphics card functionality. These secondary electronic components may include one or more voltage regulator module (VRM) chips, random access memory (RAM) chips, and various other smaller components. Figure 1A schematic diagram of a typical graphics card with various electronic components integrated onto the motherboard is shown. A known example of this type of graphics card is the Nvidia GEForce 2080 Ti. While the GPU is the primary source of waste heat, the VRM and RAM chips also generate significant amounts of heat during operation, which requires cooling.

[0007] Because graphics cards are multi-chip modules (MCMs), thermal design presents significant challenges. This multi-chip configuration presents challenges for thermal design. A major challenge is that multiple components need to be cooled (e.g., GPU, VRM, and RAM), and these components are distributed over a relatively large area.

[0008] Another challenge is that the power load and maximum allowable operating temperature of various components differ. For example, a GPU is a high-performance device that must operate as close to its optimal operating temperature as possible, thus requiring enhanced cooling. On the other hand, a VRM chip is a low-power component with a wider operating temperature range, so it does not require the same level of cooling as the GPU.

[0009] Liquid cooling is highly favored compared to air cooling due to its enhanced cooling performance and compactness. In this case, the aforementioned graphics card cooling challenges become more severe due to hydraulic limitations. The volumetric flow rate of water available for cooling is limited. Since the volumetric flow rate of the coolant at the chip level determines its efficiency in cooling the chip, distributing or spreading that flow across a large area and / or multiple chips can reduce overall cooling efficiency. This is not ideal because the GPU is the core component of the graphics card and requires the highest level of cooling.

[0010] Existing liquid-cooled graphics card thermal management technologies employ a "collateral damage" approach. This means that the limited supply of liquid coolant is diverted from cooling the GPU to cooling auxiliary components. Figure 2 A known liquid-based cooling device is shown that employs this "collateral damage" method to cool a graphics card. Figure 2 The cooling device shown has a metal plate pressed onto a circuit board, which contacts the GPU, RAM, and VRM chips via a thermal interface material (TIM). A metal or plastic cover is sealed to the top side of the plate, and coolant flows throughout the plate via conduits and possibly machined fins to improve localized heat transfer.

[0011] This approach has several problems: (i) it suffers from ineffective cooling of the GPU due to the scarcity of coolant resources and the associated overall cooling potential bypassing the GPU, which requires the highest level of cooling; (ii) it suffers from power concentration because a large amount of power is required to ensure hydraulic performance across the entire area of ​​the graphics card; and (iii) it is also incompatible with various graphics card designs because each graphics card architecture and each subsequent new version requires a completely new thermo-hydraulic design.

[0012] Therefore, a cooling solution for cooling MCMs is needed that at least partially overcomes the aforementioned drawbacks. Summary of the Invention

[0013] According to the present invention, these and other problems are solved by a cooling device for cooling multiple electronic components on a shared circuit board.

[0014] Therefore, the present invention provides an apparatus as described in detail in the independent claims, and advantageous embodiments are provided in the dependent claims.

[0015] One object of the present invention is to provide a cooling device suitable for cooling MCMs, such as graphics cards with high performance, improved efficiency, and versatility in configuration.

[0016] According to one aspect of the present invention, a thermal cooling device is provided for cooling electronic components of a circuit board. The electronic components may include primary electronic components and one or more secondary electronic components. The thermal cooling device may include a first cooling component, which may include a first cooling member configured to contact the surface of the primary electronic component. The first cooling member may be configured to be in fluid communication to achieve effective cooling of the hot surfaces of the primary electronic components. The thermal cooling device may include a second cooling component, which may include a second cooling member configured to contact the respective hot surfaces of one or more secondary electronic components to achieve effective conductive cooling of the one or more secondary electronic components. The second cooling member may be thermally coupled to the first cooling member.

[0017] According to some embodiments of the present invention, the second cooling component may extend around the outer periphery of the first cooling component.

[0018] According to some embodiments of the present invention, a thermally bonded region is operatively defined between the first cooling component and the second cooling component, the thermally bonded region extending around the outer periphery of the first cooling component to form a temperature drop around the outer periphery of the first cooling component.

[0019] According to some embodiments of the present invention, the first cooling component and the second cooling component can be independent and different components, and the second cooling component can be physically adjacent to the first cooling component.

[0020] According to some embodiments of the present invention, the first cooling member and the second cooling member are both formed from a common substrate or integrally formed with each other.

[0021] According to some embodiments of the present invention, the second cooling member may have a near-end cooling region and a far-end cooling region. The second cooling member may be thermally coupled to one or more secondary electronic components in the far-end cooling region.

[0022] According to some embodiments of the invention, a thermal gradient is operably established between a cooling proximal region and a cooling distal region, such that heat generated by one or more secondary components transfers heat to the first cooling component.

[0023] According to some embodiments of the present invention, a first cooling member has a first covering area, a second cooling member has a second covering area, and the first covering area is smaller than the second covering area.

[0024] According to some embodiments of the present invention, the first cooling component may be configured to achieve effective convection cooling of a first surface region of the first cooling member. The first surface region may at least overlap with the coverage area of ​​the main electronic component.

[0025] According to some embodiments of the present invention, the first surface area may be larger than the coverage area of ​​the main electronic components.

[0026] According to some embodiments of the present invention, the second cooling component may be a conductive plate, the conductive plate including a first region having a first thickness and a second region having a second thickness, the first thickness being greater than the second thickness.

[0027] According to some embodiments of the present invention, the first region may overlap with one or more secondary electronic components in a first group, and the second region may overlap with one or more secondary electronic components in a second group.

[0028] According to some embodiments of the present invention, the device may further include a third cooling component, the third cooling component including a third cooling member configured to achieve effective conductive cooling of one or more electronic components at the third level, the third cooling member being thermally coupled to the second cooling member.

[0029] According to some embodiments of the present invention, when the first cooling component and the second cooling component are independent and different components, the first cooling component is formed of a first conductive material, the second cooling surface is formed of a second conductive material, and the first conductive material is different from the second conductive material.

[0030] According to some embodiments of the present invention, the first cooling member and the second cooling member are formed of the same conductive material.

[0031] According to some embodiments of the present invention, the thickness of the first cooling member is different from the thickness of the second cooling member.

[0032] According to some embodiments of the present invention, the first cooling member may be formed of copper and the second cooling member may be formed of aluminum.

[0033] According to some embodiments of the present invention, the second cooling member may define one or more heat conduction channels. The one or more heat conduction channels define a heat conduction path along which heat will preferentially be transferred.

[0034] According to some embodiments of the invention, the first cooling component may include a housing defining a chamber configured to facilitate fluid circulation. The first cooling component may also include a conductive plate extending laterally from the housing. Thermal suppression is operatively formed in the conductive plate.

[0035] According to some embodiments of the present invention, the chamber may be encapsulated with a jet orifice plate through which fluid impacts the first cooling member to achieve effective convective cooling of the first cooling member. This effective convective cooling enables corresponding effective cooling of the main electronic components.

[0036] According to some embodiments of the present invention, convection cooling operably implemented by a first cooling component has a first cooling efficiency, and conduction cooling operably implemented by a second cooling component has a second cooling efficiency lower than the first cooling efficiency, so as to operably form a temperature drop at the outer periphery of the first cooling component.

[0037] In summary, the apparatus according to the various embodiments described herein provides targeted liquid-based cooling of primary electronic components to maximize cooling in the thermally critical region. Cooling of secondary components on the same shared board is achieved by conducting heat away from these components. This heat is then transferred to the same liquid coolant used for the primary electronic components. The present invention provides effective and efficient cooling for multi-chip modules, or virtually any circuit board with multiple electrical or electronic components that may require varying degrees or targeted cooling. The apparatus according to various embodiments of the invention can also be readily adapted to cool various configurations of MCMs (including more than one primary electronic component and corresponding secondary or tertiary electronic components).

[0038] Compared to conventional "collateral damage" methods, this invention provides improved thermal management for MCM cooling because the device is designed to concentrate high levels of cooling on the core components on the board. An innovative implementation of the thermal interface between the convection cooling components and the heat manifold (providing conductive cooling) and the resulting cold zones triggers thermal diffusion from the heated peripheral secondary electronics to the cold zones generated around the primary electronics, ultimately transferred to the convection cooling components. By concentrating all available coolant at the center of the high-power primary electronics, cooling of the core components, as well as the conductive plates, can be concentrated, thereby cooling one or more peripheral secondary electronics. The result is targeted, high-performance convection cooling at critical locations and conductive cooling on less critical electronics on the board. Therefore, the cooling potential of a compact convection-based cooler with a limited cooling dose is optimally utilized to achieve efficient, targeted, and general cooling of multiple components of the MCM. Attached Figure Description

[0039] This application will now be described with reference to the accompanying drawings, in which:

[0040] Figure 1 This is a schematic diagram of a typical graphics card as an example of an MCM, which can be properly cooled using a cooling device according to the invention.

[0041] Figure 2 A schematic diagram of a known liquid-based cooler for cooling graphics cards is shown.

[0042] Figure 3 A cross-sectional view of a cooling device for cooling a multi-chip circuit board according to the present invention is shown schematically.

[0043] Figure 4a It is based on the present invention Figure 3 A schematic exploded view of the device.

[0044] Figure 4b It is based on the present invention Figure 3 A schematic top view of the device.

[0045] Figure 5 This is a schematic exploded view of the cooling device according to the present invention.

[0046] Figure 6 Simulation results of the heat distribution pattern of a circuit board operably cooled by the cooling device according to the invention are shown. Detailed Implementation

[0047] The present invention will now be described by way of example with reference to the accompanying drawings.

[0048] Many terms used in describing the various embodiments of the invention are synonymous or interchangeable. For example, the term “auxiliary” can be used synonymously with “secondary” or “tertiary.” The term “circuit board” can be used synonymously with “printed circuit board,” “board,” or “motherboard.” The term “electronic component” can be used synonymously with “electronic device,” referring to various types of “integrated circuits,” “chips,” or any other type of electronic component. The term “liquid-based cooler” can be used synonymously with “liquid cooler” or “water block.” As used herein, unless the context otherwise requires, the terms “coupled to” or “connected to” are intended to include direct coupling or connection (where two elements coupled or connected to each other are in contact with each other) and indirect coupling or connection (where at least one additional element is located between the two elements). Therefore, the terms “coupled to,” “coupled,” “connected to,” and “connected” are used synonymously.

[0049] The following discussion provides many exemplary embodiments of the subject matter of this invention. Although each embodiment represents a single combination of inventive elements, the subject matter of this invention is considered to include all possible combinations of the disclosed elements. Thus, if one embodiment includes elements A, B, and C, and a second embodiment includes elements B and D, the subject matter of this invention is also considered to include other remaining combinations of A, B, C, or D, even if not explicitly disclosed.

[0050] For simplicity and clarity, reference numerals may be repeated in the figures to indicate corresponding or similar elements. Numerous details set forth provide an understanding of the examples described herein. These examples can be implemented without these details. In other instances, well-known methods, procedures, and components have not been described in detail to avoid obscuring the examples described. This description should not be construed as limiting the scope to the examples described herein.

[0051] According to embodiments of the present invention, an apparatus for cooling electronic components on a circuit board is provided. The circuit board can be any type of circuit board on which multiple electronic components are integrated. For example, such a circuit board can be a printed circuit board (PCB) comprising multiple integrated circuits or chips forming a multi-chip module (MCM). Examples of such circuit boards include, but are not limited to, CPU cards or graphics cards. The electronic components can include at least one primary electronic component, or simply “primary component”. At least one primary electronic component 110 can be a processing unit. The electronic components also include one or more secondary electronic components. Secondary electronic components can be peripheral auxiliary components configured to support the function of the primary component. However, it should be noted that, in the context of the present invention, primary and secondary electronic components are distinguished primarily based on their power load and maximum permissible operating temperature rather than their function. Primary electronic components, such as processing units, are typically high-power and therefore generate a significant amount of heat during operation, requiring a high level of intensive cooling to keep the component within its permissible operating temperature range. On the other hand, secondary electronic components are typically low-power and require a relatively low level of cooling compared to primary electronic components. Primary electronic components are typically located in the central region of the circuit board, with secondary and tertiary electronic components arranged around or around the primary electronic components. However, it should be understood that the relative positioning and arrangement of the primary, secondary, and tertiary electronic components can vary depending on the design of the MCM. Therefore, the cooling device according to the invention can employ various configurations compatible with different MCMs and can be installed into different MCMs.

[0052] An exemplary MCM that can be properly cooled using the apparatus of the present invention is a graphics card, such as... Figure 1 As shown. Figure 1 The graphics card 100 shown includes a GPU 110, which can be considered a primary electronic component. The graphics card also includes multiple RAM chips 120a and VRM chips 120b, which can be considered secondary electronic components. The graphics card may also have other secondary or tertiary electronic components. Primary and auxiliary (secondary and tertiary) electronic components are integrated onto the motherboard to form the graphics card 100.

[0053] Cooling structure

[0054] Combination Figure 3 A schematic diagram of the cooling structure according to the present invention is shown. Figure 3 A schematic cross-sectional view of a cooling device for cooling electronic components on a circuit board 1 according to an embodiment of the present invention is shown. Figure 3As can be seen, the device includes a first cooling component and a second cooling component. The first cooling component defines a main cooling zone or area and is configured to cool the main electronic component 10. The second cooling component is configured to cool one or more secondary electronic components 20. The first cooling component is implemented based on convective heat transfer technology or convection cooling. The first cooling component acts as a heat sink. The second cooling component is implemented based on conductive heat transfer technology or conductive cooling.

[0055] The second cooling component is thermally coupled to the first cooling component. When both the first and second cooling components are formed as discrete elements, this thermal coupling can be achieved by thermally coupling the first cooling member 310 of the first cooling component to the second cooling member 320 of the second cooling component. Operablely, a thermally bonded area is defined between the first and second cooling components. The thermally bonded area can extend around the outer periphery of the main electronic component 10, creating a temperature drop around the outer periphery of the main electronic component 10.

[0056] This cooling structure concentrates high-level convection cooling on the core electronic component 10 of the MCM. The innovative implementation of the thermal bonding between the convection cooling component and the conduction cooling component, and the resulting cold zone, triggers thermal diffusion from the hot peripheral secondary electronic component 20 to the cold zone generated around the main electronic component 10. This thermal diffusion is ultimately transferred to and removed by the convection cooling component.

[0057] According to some embodiments, convection cooling operably implemented by the first cooling component has a first cooling efficiency. Conductive cooling operably implemented by the second cooling component has a second cooling efficiency lower than the first cooling efficiency, thereby operably creating a temperature drop around the outer periphery of the first cooling component.

[0058] The first and second cooling components 310 and 320 can be made of any suitable thermally conductive material. Metallic thermally conductive materials (such as copper and aluminum) are particularly advantageous due to their desirable thermal properties. For example, the first cooling component 310 can preferably be made of a metal such as copper to take advantage of its excellent thermal conductivity. The second cooling component 320 can be made of a conductive material such as aluminum, which has sufficient thermal conductivity and also has advantages such as light weight, high rigidity, and low cost. It should be understood that other types of metallic or non-metallic thermally conductive materials can be used in the first or second cooling components to achieve the desired thermal properties.

[0059] First cooling component

[0060] As previously described, the first cooling component for cooling the main electronic component 10 is achieved using convection cooling, preferably liquid-based convection cooling, which is configured to provide high-intensity, high-efficiency cooling. In this invention, liquid and fluid are interchangeable.

[0061] The first cooling component may include a first cooling member. The first cooling member is configured to contact the surface of a primary electronic component to be cooled. In particular, the first cooling member defines a hot surface. The hot surface is configured to make thermal contact with the surface of the primary electronic component to conduct heat from the primary electronic component. The thermal contact may be enhanced or aided by using thermal adhesives, heat-sensitive adhesives, and / or heat-sensitive greases.

[0062] The first cooling component can be in the form of a thermal substrate, with one side in contact with the main electronic components. The other side of the substrate can be configured to be in fluid communication to achieve effective convection cooling.

[0063] According to one embodiment, the first cooling component can be implemented based on the principle of convective heat transfer. Convective heat transfer relates to the heat transfer between an object and a fluid flowing on or within it, a result of the interaction between the two objects. More specifically, conjugate heat transfer refers to the situation where non-uniform convective cooling of the fluid phase on a solid substrate creates a thermal gradient within the solid, allowing heat to flow from hot to cold areas within the solid via conduction. This is the mechanism by which the first cooling component establishes a heat transfer path from the peripheral electronics through the conductive plate to the coolant fluid within the first cooling component.

[0064] According to one embodiment, the conjugate convective heat transfer utilized by the first cooling component employs a liquid-based convection cooling component, such as... Figure 4a and 4b The components are shown. However, those skilled in the art will understand that other fluid-based convection cooling mechanisms can be utilized, provided they provide enhanced cooling of the main electronic components 110 with high cooling efficiency. However, in general, liquid-based cooling is preferred because it enhances heat transfer efficiency compared to air-based convection cooling.

[0065] According to some embodiments, the first cooling component includes a housing defining a chamber configured to facilitate fluid circulation. The first cooling component includes a conductive plate extending laterally from the housing. Thermal suppression can be operatively formed in the conductive plate. The chamber may encapsulate a jet orifice plate through which fluid impinges on the first cooling component to achieve effective convective cooling of the first cooling component, thereby achieving corresponding effective cooling of key electronic components.

[0066] The following will combine Figure 4a and 4b The advantageous convection cooling according to the invention is described in detail.

[0067] According to some embodiments, high-level convection cooling can utilize thermal hydraulics to achieve efficient jet array impingement heat transfer directly on the surface of key electronic components, such as processing units like CPUs or GPUs. This can be achieved through a hermetically sealed water-cooled impingement jet assembly (or simply a "water head") mounted on the main processing unit. Jet array impingement heat transfer involves forcing high-speed water jets from a patterned jet array onto a heated metal substrate (referred to as a hot plate).

[0068] Figure 4a and 4b An exemplary embodiment of such a first cooling component is shown. The impingement jet assembly may include a housing 451 having a fluid inlet 452 and a fluid outlet 453. The fluid inlet 452 may be in fluid communication with a pressurization chamber 454. The pressurization chamber 454 may be entirely defined within the housing and includes a jet orifice plate 456 defining a plurality of jet holes. The jet holes may be distributed on the surface of the jet orifice plate to form an impingement microjet array plate 456. The impingement microjet array provides a fluid outlet through which pressurized fluid can be operatively exited from the pressurization chamber. Upon exiting the impingement microjet array, the pressurized fluid may contact a hot surface and operatively dissipate heat from the hot surface. The impingement jet assembly 450 is configured to operatively direct heated fluid away from the first cooling member 410 (e.g., a heated base) to exit the assembly via the fluid outlet 453. The first cooling member 410 is arranged to conduct heat away from the main electronic component 110. The first cooling member 410 may include a flat upper surface such that pressurized fluid contacts and dissipates heat from the flat surface. In another configuration, the upper surface of the first cooling member 410 may not be planar. For example, it may include one or more raised surfaces or ruggednesses that operatively increase the contact surface area of ​​the pressurized fluid. These raised surfaces or ruggednesses may take one or more different geometries, such as recesses or fins projecting upward toward the jet orifice plate 456.

[0069] In order to effectively guide the heated fluid away from the first cooling member 410, the housing may define at least one outlet channel configured to deliver the fluid leaving the impact microjet array to the fluid outlet 453.

[0070] The housing 451 is configured to be top-mounted onto a major electronic component, such as a CPU or GPU. The housing can be secured relative to the major electronic component 110 by any suitable means of fixing, such as mechanically securing the housing with threaded screws relative to the substrate on which the major electronic component resides.

[0071] By mounting a housing relative to the top of the main electronic component to be cooled, the liquid passing through the jet orifice is effectively guided downwards under pressure in the direction toward the main electronic component.

[0072] The impact microjets array plate 456 can define the bottom of the pressurization chamber. The pressurization chamber also includes sidewalls extending upward from the bottom. In this arrangement, the outlet channel ideally shares the sidewall with the pressurization chamber, which is located on a first side of the sidewall, and the outlet channel is located on a second side of the sidewall.

[0073] In the first structure of the water cooling head, such as Figure 4b As shown, the outlet channels are completely confined within the housing, such that the housing includes different pressurization chambers and different outlet channels, each in fluid communication with a fluid inlet and a fluid outlet 453, respectively. Figure 4a In the exemplary configuration shown, both the fluid inlet and the fluid outlet are vertically offset from the jet orifice. In some configurations, at least one of the inlet and outlet is vertically offset (not shown).

[0074] In this configuration, a pressurization chamber 454 is disposed on a first side of an impact microjets array plate 456, and an outlet channel is disposed on a second side of the impact microjets array plate 456. The impact microjets array plate 456 defines at least a portion of the upper surface of the outlet channel, and a hot surface defines at least a portion of the lower surface of the outlet channel. Figure 4a and 4b In this example, the first cooling component 410 is formed of a thermally conductive material such as copper and is mechanically fixed to the remainder of the housing 451. In this exemplary arrangement, a flange formed by an O-ring can be disposed within an O-ring channel 266 formed in the housing, and when the heated substrate 410 is mechanically fixed to the housing 451, the flange forms a fluid tight seal, preventing water entering the outlet channel from leaking out before exiting through the fluid outlet 453. It should be understood that the first cooling component 410 can also be formed as an integral part of the entire housing.

[0075] The high velocity of the jet enables an exceptionally high convective heat transfer coefficient, allowing for efficient cooling of high-power primary electronic components (such as GPUs) without wasting any coolant volumetric flow on less critical and significantly lower-power auxiliary (secondary / tertiary) electronic components (such as RAM and VRMs). The pressure drop is likely almost entirely related to the contraction of the fluid entering the nozzle, making it moderate at the target volumetric flow rate.

[0076] In addition to the features and constructions that will be understood from the discussion herein, the first cooling component may include those features and components described in the published international patent application PCT / EP2019 / 070713.

[0077] Second cooling component

[0078] The device according to the invention further includes a second cooling member configured for cooling one or more secondary electronic components. The second cooling member is thermally coupled to the first cooling member. According to some embodiments, the second cooling member may extend around the outer periphery of the first cooling member. For example, the second cooling member may form a skirt region extending laterally from the first cooling member.

[0079] according to Figure 4a and 4b In the illustrated embodiment, the second cooling component includes a second cooling member 420. It should be understood that the second cooling component itself can be equivalent to the second cooling member 420, and therefore the two terms can be used interchangeably in some embodiments. Thermal coupling is achieved by thermally coupling the first cooling member 410 of the first cooling component to the second cooling member 420 of the second cooling component.

[0080] The second cooling member 420 includes a cooling proximal region adjacent to the outer periphery of the first cooling member. The cooling proximal region is configured to be thermally coupled to the first cooling member 410 of the first cooling member. It operatively creates a thermal bond between the first and second cooling members. The thermal bond region extends around the outer periphery of the primary electronic component. During the formation of this thermal bond, a temperature drop or cold zone is formed around the outer periphery of the first cooling member surrounding the primary electronic component. This effectively establishes a conjugate heat transfer mechanism due to strong convective cooling in the primary cooling region and weak convective cooling in the adjacent cooling region, such that the path of least thermal resistance lies within the second cooling member 420 via conductive heat transfer between the heat source (auxiliary electronic device) and the heat sink (first cooling member). The cold zone is the lowest temperature region of the first and second cooling members 410, 420.

[0081] The second cooling member 420 also includes a cooling distal region. The cooling distal region corresponds to a region of the second cooling member 420 that is configured to be in thermal contact with one or more secondary electronic components to facilitate heat conduction.

[0082] During operation, the temperature of the cooling distal region is raised by heat generated by one or more secondary electronic components. A thermal gradient is operably established between the cooling proximal region and the cooling distal region. The resulting thermal gradient ensures that heat generated by the secondary electronic components is transferred to the first cooling member 410 cooled by the first cooling component. Thus, the cooling distal region operably absorbs heat from the secondary electronic components via conductive heat transfer. The area in the second cooling member 420 where conductive heat transfer occurs effectively forms one or more conductive cooling regions.

[0083] According to some embodiments, the second cooling member 420 may be a heat-conducting plate configured to act as a heat manifold to conduct heat from one or more secondary electronic components to the first cooling member of the first cooling member. Specifically, this can be achieved by arranging the heat-conducting plate in thermal contact with one or more surfaces of one or more secondary electronic components. For example, thermal contact can be achieved by physically abutting the surface of the heat-conducting plate against one or more surfaces of one or more secondary electronic components. Thermal contact can be aided or enhanced by placing a thermal grease, hot grease, and / or thermal adhesive between the two surfaces.

[0084] As previously described, the second cooling component may form a skirt region extending laterally from the first cooling component. It should be understood that, depending on the arrangement of the secondary electronic components, the skirt region formed by the second cooling component can adopt any suitable shape to achieve adequate thermal coupling with one or more secondary electronic components. For example, the first and second cooling components may be arranged to match a specific circuit board design.

[0085] According to some embodiments of the invention, the second cooling member 420 may operably define one or more heat conduction channels. The heat conduction channels define a heat conduction path along which heat will preferentially be transferred. Operablely, one or more channels with increased cross-sectional areas above or below the heat manifold may be strategically arranged to thermally connect one or more discrete secondary heat sources (secondary electronic components) to the primary cooling area. This preferably provides lower thermal resistance and lower operating temperatures for subsequent components without requiring expansion across the entire thickness of the heat manifold, only for one or a few secondary components. Essentially, the conduction channels function as lateral or transverse heat pathways.

[0086] Figure 5 An exploded schematic diagram showing an exemplary cooling system that can be used to cool a graphics card 100. From Figure 5 As can be seen, the first cooling component is a thermal substrate 510 formed of a thermally conductive material. The second cooling component is a conductive plate 520 formed of a thermally conductive material. The conductive plate 520 acts as a heat conduit to conduct heat from the secondary electronic device to the thermal substrate 510. In this example, the conductive plate 520 has an opening configured to receive the thermal substrate 510. The thermal substrate 510 is configured to mate with the receiving opening of the conductive plate 520. The thermal substrate has a flange configured to mate with a receiving frame of the thermal substrate 510. The flange and the receiving frame are configured to form an overlapping engagement area.

[0087] from Figure 5As can be seen, the thermal substrate 510 is located essentially in the central region of the cooling device to at least overlap and thermally contact the GPU 110. The conductive plate 520 is configured to extend laterally from all sides of the thermal substrate 510 to thermally couple to the VRM chip 120b and RAM chip 120a. A thermal interface material (TIM) 530 facilitates thermal coupling between the conductive plate and the RAM / VRM chips. Thermal contact between the thermal plate 510 and the CPU 110 can be enhanced using thermal grease. The thermal busbar has an asymmetrical shape, with one side larger than the others to facilitate cooling of the large number of VRM / RAM chips on that particular side.

[0088] According to some embodiments, the second cooling member can be a conductive plate of uniform thickness. According to some other embodiments, the second cooling member can be a conductive plate of non-uniform or varying thickness. One example of such a non-uniform thickness configuration is one or more lateral thermal paths. Since conductive plates used in compact cooling devices tend to be relatively thin (e.g., 2 mm thick), the thickness of the conductive plate significantly affects the cooling effect provided by the conductive plate. For example, the thermal resistance in the lateral direction of the conductive plate plane is inversely proportional to the thickness of the conductive plate. Therefore, by increasing the thickness, the effective diffusion thermal resistance between the secondary component and the first cooling member is reduced. During operation, the effective thermal resistance between the heat source and the heat sink is reduced, which positively affects the operating temperature of the electronic components.

[0089] Therefore, the cooling level supplied to different secondary electronic components can be adjusted by changing the thickness of the region of the conductive plate that is thermally coupled to the secondary electronic components. To achieve this, the conductive plate may include a first region with a first thickness and a second region with a second thickness, the first thickness being greater than the second thickness. Thus, the conductive plate can be configured such that the first region overlaps with a first group of one or more secondary electronic components, and the second region overlaps with a second group of one or more secondary electronic components. For example, the thermal substrate can be configured with thicker regions that overlap and thermally contact relatively high-power secondary electronic devices to effectively balance the temperature. In graphics card cooling, the VRM typically generates more heat than RAM, thus requiring a higher level of cooling. By configuring the conductive plate with a thicker region that thermally overlaps with the VRM, more balanced cooling can be achieved.

[0090] It should be understood that the heat transfer plate can be configured with various thickness profiles. It should also be understood that the thickness variation can be gradual, creating different stages, or continuous / gradual, to achieve different cooling distributions, thus suiting a variety of applications.

[0091] According to some embodiments of the invention, the device may further include a third cooling component. Similar to the second cooling component, the third cooling component may include a third cooling member configured to achieve effective conductive cooling of one or more third-level electronic components. The various embodiments and configurations described in conjunction with the second cooling component are equally applicable to the third cooling component and will not be repeated here. It should be understood that the cooling device according to the invention may include other levels of cooling components to achieve cooling of boards with various auxiliary electronic component shapes. Therefore, the cooling device of the invention is versatile because it can be easily modified and / or adjusted to suit the cooling of boards with various shapes and quantities of primary and auxiliary electronic components of various sizes.

[0092] Effective cooling of the first and second cooling components

[0093] The cooling device according to the invention utilizes the excellent convection (e.g., thermo-hydraulic) performance of the first cooling component to cool not only high-power main electronic components but also to generate thermal suppression in the second cooling component, thereby initiating a conjugate heat transfer mechanism. According to some embodiments, the convection cooling operably achieved by the first cooling component has a first cooling efficiency. The conduction cooling operably achieved by the second cooling component has a second cooling efficiency lower than the first cooling efficiency, thereby operably creating a temperature drop around the outer periphery of the first cooling component.

[0094] Thermal suppression effectively absorbs lower amounts of heat generated by one or more secondary electronic components and transfers them to the primary cooling component. By concentrating all available coolant at the primary electronic component, the first cooling component cools the core primary electronic component with maximum cooling efficiency within the cooling unit / assembly. The cooling effect of the first cooling component extends to a second cooling component, which operably cools the secondary electronic components at a relatively low but sufficient level (e.g., proportional to its cooling efficiency). The result is high-performance convection-based cooling for critical locations and conduction-based cooling for less critical secondary electronics on the circuit board.

[0095] The area where convection cooling occurs can be referred to as the convection cooling region. The surface of the main electronic component that is in thermal contact with the first cooling component can be referred to as the thermal contact surface of the main electronic component. The convection cooling region can at least overlap with the area of ​​the thermal contact surface of the main electronic component to achieve effective high-level cooling of the main electronic component.

[0096] The effect of this high-level, high-intensity cooling of the main electronic components is to efficiently remove the waste heat generated by the high-power main electronic components, ensuring that the component operates below its maximum operating temperature. Another advantageous effect achieved through this construction is that the high-level cooling at the main electronic components creates a cold zone around the outer periphery of the first cooling component.

[0097] Because the proximal cooling region of the second cooling member is in close thermal contact with the first cooling member, which achieves a high level of cooling, the distal cooling region tends to have the lowest temperature of the second cooling member. Conversely, because the distal cooling region of the second cooling member is thermally coupled to the secondary electronic components, it operatively absorbs the low-level heat generated by the secondary electronic components, and therefore tends to have a higher temperature than the proximal cooling region. Effectively, a thermal gradient can be induced or established between the proximal and distal cooling regions of the second cooling member. Therefore, heat generated by one or more secondary components will be transferred via the first cooling member to the first cooling member and ultimately dissipated from the first cooling member.

[0098] Taking the cooling graphics card 100 as an example, a high-power GPU is cooled to a high level via a thermal substrate 510 (e.g., a copper substrate). A thermal bond is formed around the periphery of the centrally cooled thermal substrate between the thermal substrate and a heat busbar or conductive plate 520 (e.g., an aluminum plate). During this thermal bond formation, a cold zone is generated in the near-cooling region of the heat busbar 520 because the near-cooling region of the heat busbar 520 is in direct contact with the convection-cooled copper substrate 510. This cold zone represents the lowest temperature region of the heat busbar 520. When the RAM chip 120a and VRM chip 120b generate heat, the cold zone creates a thermal gradient between the hot chip region and the thermal bond region. This thermal gradient ensures that the heat generated by the RAM chip 120a and VRM chip 120b is conducted to the thermal substrate 510 cooled by the convection cooler. Since the heated GPU 110 tends to generate a large amount of heat, the absence of such a cool zone / temperature drop creates a region of highest temperature, which can generate a thermal gradient in the opposite direction, transferring the heat generated by the GPU 110 to the far end of the thermal busbar 520. This will have the adverse effect of heating the VRM chip 120b and RAM chip 120a instead of cooling them.

[0099] To better illustrate the advantageous effects obtained through the present invention, Figure 6 The image shows exemplary simulation results of the temperature distribution of a graphics card. Figure 6 As can be seen, the lowest temperature cold zone 600 is generated around the periphery of the thermal substrate or GPU. Due to the heat generated by the GPU 110, the center of the thermal substrate is at a higher temperature. Due to the heat generated by these peripheral chips, the peripheral, more distant regions where the VRM and RAM chips are located are at a higher temperature. Therefore, heat is carried from the more distant regions of the thermal busbar to the cold zone 600 and then removed by the first cooling component. Thus, through careful design of the thermal busbar and thermal bonding areas, the thermal gradient is sufficient to transfer heat between the heat sources (i.e., RAM and VRM) and the heat sink (liquid-cooled substrate) while keeping them well below their maximum permissible operating temperature.

[0100] Generally, it is sufficient for the convection cooling region to be substantially the same size as the thermal contact surface of the main electronic component. However, in some embodiments, the convection cooling region can be larger than the thermal contact surface of the main electronic component. This configuration is particularly useful in the case of a monolithic cooling component. As a result of this configuration, the convection cooling region extending beyond and around the thermal contact surface on the first cooling component contributes more to effective convection cooling at a much lower level compared to the overlapping region. Therefore, the heat / temperature drop is enhanced, which in turn affects the colder area with a lower temperature.

[0101] In some embodiments, the first cooling member and the second cooling member may be formed from a common substrate. These two cooling members may be integrally formed with each other. The integrally formed first and second cooling members (collectively referred to as the integral cooling member) may take the form of a heat-conducting plate extending through an area overlapping the integral surfaces of the primary and secondary electronic components requiring effective cooling. The integral cooling member may define a first side surface and an opposing second side surface. The first cooling component (i.e., a convection cooling component) may be mounted to the first side surface. The second side surface may be in thermal contact with the primary and secondary electronic components.

[0102] The thermal properties of the joint area can be modified by constructing a single component with various dimensional profiles, particularly based on thickness profiles based on principles similar to those described in previous paragraphs, and will not be repeated here.

[0103] In an alternative embodiment, both the first cooling member and the second cooling member can be independent and distinct components. The second cooling member can be physically adjacent to the first cooling member. Figure 5 The example shown corresponds to such an embodiment. In embodiments where the first and second cooling components are independent and distinct components, the thermal properties of the mating region can be varied, in addition to the size or thickness profile, by the thermally conductive material used to form each component. The first and second cooling components can have the same or different thicknesses. For example, the first cooling component can be formed of a first conductive material. The second cooling component can be formed of a second thermally conductive material. Depending on the specific design, the first and second thermally conductive materials can be the same or different materials to facilitate different cooling operations. For example, the first cooling component may preferably be made of a metal such as copper to take advantage of its desired thermal properties, such as high thermal conductivity. The second cooling component can be made of a thermally conductive material, such as aluminum, which has sufficient thermal conductivity and benefits from light weight, high stiffness, and low cost. It should be understood that other types of thermally conductive materials can be used for the first and second cooling components to achieve the desired thermal properties.

[0104] When used in this specification, the term "including / comprises" is used to specify the presence of the stated feature, integer, step, or component, but does not exclude the presence or addition of one or more other features, integers, steps, components, or combinations thereof.

Claims

1. A thermal cooling device for cooling electronic components on a circuit board, the electronic components including primary electronic components and one or more secondary electronic components, the device comprising: A first cooling component, comprising a first cooling member configured to contact the thermal contact surface of the main electronic component, the first cooling member further configured to be in fluid communication to achieve effective convective cooling of the thermal contact surface of the main electronic component, the first cooling component including a microjet array defining a convective cooling region at least partially overlapping the thermal contact surface of the main electronic component, and within the convective cooling region, pressurized fluid operably directly contacts the thermal contact surface to dissipate heat from the thermal contact surface; and A second cooling component, comprising a second cooling member having a distal cooling region configured to contact the respective hot surfaces of the one or more secondary electronic components to achieve effective conductive cooling of the one or more secondary electronic components, the second cooling member having a proximal cooling region thermally coupled to the first cooling member. The convection cooling operably implemented by the first cooling component has a first cooling efficiency, and the conduction cooling operably implemented by the second cooling component has a second cooling efficiency lower than the first cooling efficiency, so as to operably create a temperature drop at the outer periphery of the first cooling component. The first cooling component includes a thermal substrate, and the second cooling component includes a conductive plate that acts as a heat conduit to conduct heat from secondary electronic devices to the thermal substrate. The conductive plate has an opening configured to receive the thermal substrate, and the thermal substrate is configured to mate with the receiving opening of the conductive plate. A thermally bonded area is operatively defined between the first cooling component and the second cooling component, the thermally bonded area extending around the outer periphery of the first cooling component to create the temperature drop at the outer periphery of the first cooling component. The first cooling component and the second cooling component are independent and different components, and the second cooling component is physically adjacent to the first cooling component.

2. The apparatus according to claim 1, wherein, The second cooling component extends around the outer periphery of the first cooling component.

3. The apparatus according to claim 1, wherein, A thermal gradient is operably established between the cooling proximal region and the cooling distal region, such that heat generated by the one or more secondary components transfers heat to the first cooling component.

4. The apparatus according to claim 1 or 2, wherein, The first cooling component has a first coverage area, and the second cooling component has a second coverage area, wherein the first coverage area is smaller than the second coverage area.

5. The apparatus according to claim 1 or 2, wherein, The coverage area of ​​the convection cooling region is larger than the coverage area of ​​the main electronic components.

6. The apparatus according to claim 1 or 2, wherein, The second cooling component is a conductive plate, which includes a first region having a first thickness and a second region having a second thickness, wherein the first thickness is greater than the second thickness.

7. The apparatus according to claim 6, wherein, The first region overlaps with one or more secondary electronic components in the first group, and the second region overlaps with one or more secondary electronic components in the second group.

8. The apparatus according to claim 1 or 2, wherein, The device further includes a third cooling component, which includes a third cooling member configured to achieve effective conductive cooling of one or more electronic components at the third level, the third cooling member being thermally coupled to the second cooling member.

9. The apparatus according to claim 1 or 2, wherein, The first cooling component and the second cooling component are independent and different components, wherein, The first cooling component is formed of a first conductive material, and the second cooling component is formed of a second conductive material, wherein the first conductive material is different from the second conductive material; or Both the first cooling component and the second cooling component are formed of the same conductive material.

10. The apparatus according to claim 9, wherein, The thickness of the first cooling component is different from the thickness of the second cooling component.

11. The apparatus according to claim 9, wherein, The first cooling component is made of copper, and the second cooling component is made of aluminum.

12. The apparatus according to claim 1 or 2, wherein, The second cooling component includes one or more heat conduction channels defined therein, the one or more heat conduction channels defining a heat conduction path along which heat will preferentially be transferred.

13. The apparatus according to claim 1 or 2, wherein, The first cooling component includes a housing defining a chamber configured to facilitate the circulation of the fluid.

14. The apparatus according to claim 13, wherein, The first cooling component also includes a conductive plate extending laterally from the housing, in which heat suppression is operably formed.

15. The apparatus according to claim 13, wherein, The chamber is encapsulated with a jet orifice plate, through which the fluid impacts the first cooling component to achieve effective convective cooling of the first cooling component, thereby achieving effective cooling of the main electronic components.

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