Isolated high voltage assembly

Abstract

An electronic assembly comprising a heat spreader comprising a thermally conductive plate comprising a first insulated surface and a second insulated surface. The first insulated surface and the second insulated surface located on opposite sides of the thermally conductive plate. The first insulated surface comprising an opening exposing the thermally conductive plate, and an electronic device comprising a body and electrical connections, the body of the electronic device thermally coupled to the thermally conductive plate through the opening.

Description

ISOLATED HIGH VOLTAGE ASSEMBLYCLAIM OF PRIORITY

[0001] This application claims the benefit of U.S. Provisional Patent Application Serial No. 63 / 552,270, filed on February 12, 2024, titled “ISOLATED HIGH VOLTAGE ASSEMBLY FOR IMPROVED THERMAL PERFORMANCE,” the contents of which is incorporated by reference herein in its entirety.FIELD OF THE INVENTION

[0002] Some examples of this disclosure relate to an isolated high voltage assembly for improved thermal performance.BACKGROUND

[0003] High voltage semiconductor devices are utilized in various high-power applications and require both thermal cooling and electrical isolation. Conventionally, these semiconductor devices are cooled by heat sinks that transfer heat away from the semiconductor devices. In these conventional configurations, the semiconductor devices are mounted to a single electrical insulation layer positioned between the device and one surface of the heat sink. Such a configuration leads to poor thermal cooling performance.BRIEF DESCRIPTION OF THE DRAWINGS

[0004] Some examples are shown for purposes of illustration and not limitation in the figures of the accompanying drawings. In the drawings, which are not necessarily drawn to scale, like numerals may describe similar components in different views or examples. It should be understood that additional and alternative examples are possible without departing from the principles of the subject matter described herein.

[0005] FIG. 1A shows an exploded perspective view of an electronic assembly including a heat spreader with a thermal interface, in accordance with examples described herein.

[0006] FIG. IB shows a side view and thermal profile of the electronic assembly in FIG. 1 A, in accordance with examples described herein.

[0007] FIG. 1C shows an assembled perspective view of the electronic assembly in FIG. 1 A, in accordance with examples described herein.

[0008] FIG. ID shows a data plot comparing thermal resistance for an electronic assembly with and without a heat spreader, in accordance with examples described herein.

[0009] FIG. IE shows a flowchart of assembly procedures for the electronic assembly including a heat spreader, in accordance with examples described herein.

[0010] FIG. 2A shows an electronic assembly including a laminated heat spreader, in accordance with examples described herein.

[0011] FIG. 2B shows an exploded perspective view of an electronic assembly including a laminated heat spreader, in accordance with examples described herein.

[0012] FIG. 2C shows a side view and thermal profile of the electronic assembly in FIG. 2B, in accordance with examples described herein.

[0013] FIG. 2D shows an assembled perspective view of the electronic assembly in FIG. 2B, in accordance with examples described herein.

[0014] FIG. 2E shows an assembled side view of the electronic assembly in FIG. 2B, in accordance with examples described herein.

[0015] FIG. 2F shows a flowchart of assembly procedures for the electronic assembly including a laminated heat spreader, in accordance with examples described herein.

[0016] FIG. 3A shows an exploded perspective view of an electronic assembly including a laminated heat spreader installed in energy product, in accordance with examples described herein.

[0017] FIG. 3B shows a flowchart of assembly procedures for the electronic assembly including a laminated heat spreader installed in an electric vehicle panel, in accordance with examples described herein.DETAILED DESCRIPTION

[0018] Various examples of this disclosure will now be described in detail with reference to the drawings. It should be noted that the relative arrangement of thecomponents and steps, the numerical expressions, and the numerical values set forth in these examples do not limit the scope of the present disclosure unless it is specifically stated otherwise. The following description of at least one example is merely illustrative in nature and is in no way intended to limit the disclosure, its application, or its uses. Techniques, systems, methods, and apparatus as known by one of ordinary skill in the relevant art may not be discussed in detail but are intended to be part of the specification where appropriate. In all the examples illustrated and discussed herein, any specific values should be interpreted to be illustrative and non-limiting. Thus, other examples may have different values. Similar reference numerals and letters refer to similar items in the following figures, and thus, once an item is defined in one figure, it is possible that it need not be further discussed for the following figures. Below, the examples will be described with reference to the accompanying figures.

[0019] Some examples are directed to a solution that seeks to provide both thermal cooling and electrical isolation for high-voltage, high-power, semiconductor devices thereby achieving improved thermal cooling performance and decreased risk of electrical faults. Some examples also seek to provide benefits of being able to easily change the number of attached electrical devices and their respective locations while still maintaining a reduced number of unique parts in the overall assembly.

[0020] In one example, an electric vehicle (EV) (e.g., electric car) utilizes an inverter to convert the direct current (DC) of the battery into alternating current (AC) (e.g., three-phase AC) to drive an electric motor of the EV drivetrain. The inverter utilizes high-voltage, high-power, semiconductor devices such as metal- oxide semi-conductor field-effect transistor (MOSFET)s, thyristors or triode for al ternati ng current (TRIAC)s for peri odi c switching of the el ectrical current being supplied from the batteries to the motor during acceleration and from the motor to the batteries during regenerative braking. During operation, these high voltage / power semiconductor devices generate significant heat that can damage the devices and other EV components / structures. In order to ensure optimal performance and avoid failure, these high-voltage, high-power, semiconductor devices are cooled with a heat sink which is an active or passive metallic mass that removes heat from the high-voltage, high-power, semiconductors. Rather than mounting the high voltage / power semiconductor devices directly to the heatsink or to the heat sink via an additional electrical insulation layer, an example solution described herein utilizes an intermediate device herein referred to as a “heat spreader” that is positioned in between the high voltage / power semiconductor devices and the insulation of the heat sink. Functions of the heat spreader include improved thermal performance by spreading the heat generated by the high voltage / power semiconductor devices over a larger area of the heat sink, and electrical isolation by insulating the high voltage / power semiconductor devices from the heat sink.

[0021] Benefits of the methods, devices and systems include but are not limited to improved thermal performance and electrical isolation of high voltage / power semiconductor devices in various applications. It is noted that although the examples described herein are focused on high-voltage, high-power, semiconductor switching devices of an inverter circuit for controlling the drive train of an EV, the heat spreader solution can be implemented in any electronic assembly application where improved thermal performance and electrical isolation are desired for high-voltage, high-power, electrical devices both of passive and active types (e.g., semiconductor devices, electro-mechanical relays, capacitors, etc.).

[0022] FIG. 1A shows an exploded perspective view 100 of an electronic assembly including a heat spreader with a thermal interface. The electronic assembly generally includes electronic devices 104 (e.g., high-voltage, high- power, semi-conductor switches) electrically connected (e.g., soldered, press-fit, etc.) to a printed circuit board (PCB) 102 which may have other connected electrical components such as electrical traces, capacitors, inductors, resistors, etc. (not shown) for supporting operation of the semi-conductor switches. These other components are not show for sake of clarity. In one example, the semi-conductor switches and other components may form part of an inverter circuit for driving an AC motor of an EV.

[0023] Also included in the electronic assembly is a thermal interface material (TIM) 106, heat spreader 108, electrical insulation 110, and heat sink 112. Rather than thermally couple electronic devices 104 directly to heat sink 112 using only TIM 106, intermediate components are utilized to both spread the heat produced by electronic devices 104 and to electrically insulate electronic devices 104. More specifically, TIM 106 is a sheet of material that exhibits good thermal conductiveproperties and good electrical insulation properties but is not required to exhibit electrical insulation properties in this example. For example, boron nitride filled polymers, alumina filled silicones, and ceramic filled epoxies are materials that exhibit good thermal conductive properties and good electrical insulation properties. Some metal filled polymers, such as copper particle filled composites and silver filled composites are materials that exhibit good thermal conductive properties but do not exhibit electrical insulation properties. Heat spreader 108 is a plate of thermally conductive material (e.g., aluminum, copper, etc.).

[0024] The components of the assembly are generally connected to other another via brazing, thermal materials (e.g., adhesive) or a combination of both techniques. For example, electronic devices 104 may be soldered to PCB 102, thermal interface material 106 may be connected on one side to electronic devices 104 via thermal adhesive and connected on the other side to heat spreader 108. The other side (bottom side) of heat spreader 108 is then connected to heat sink 112 via electrical insulation 110 as an intermediary. Electrical insulation 110 may be part of heat sink 112, part of heat spreader 108 or an independent layer placed between heat sink 112 and heat spreader 108.

[0025] The function of thermal interface material 106 and heat spreader 108 in this configuration is to provide thermal conduction between electronic devices 104 and electrically insulated heat sink 112. These properties are important for properly cooling electronic devices 104 and protecting electronic devices 104 from electrical faults that may occur from inadvertent contact and arcing with grounded components such as the heat sink 112.

[0026] Thermal interface material 106 as shown in FIG. 1A, generally conducts heat from the body of electronic devices 104. For example, electronic devices 104 may be MOSFETs having pins corresponding to a gate and main terminals of the MOSFET. These pins are generally soldered to PCB 102 and are positioned in close proximity to heat spreader 108. In order to avoid electrical arcing and / or electrical faults (e.g., chassis ground faults) due to the heat sink 112 being grounded to the vehicle chassis, TIM 106 may have electrical insulation properties to insulate electronic devices 104 from heat spreader 108, and electrical insulation 110 may be positioned between heat spreader 108 and heat sink 112 to insulate the electrical leads (not shown) of electronic devices 104 from the heat spreader 108 and to insulate the heat spreader 108 from heat sink 112.

[0027] Heat spreader 108 is beneficial for spreading heat produced by electronic devices 104 prior to be being dissipated through heat sink 112. For example, as mentioned above, electronic devices 104 may be MOSFETs that produce a significant amount heat during operation when driving the electric motor of the EV. Electronic devices 104 have relatively small bodies and therefore have small surface areas for transferring heat directly to the heat sink. In this solution, however, the heat generated by the electronic devices 104 is transferred to heat spreader 108, which has a larger surface area than that of the electronic devices 104, via thermal conduction through thermal interface material 106. The heat absorbed by heat spreader 108 is then transferred via thermal conduction to heat sink 112. In other words, by spreading the heat across the larger surface area of heat spreader 108, heat is dissipated across the electrical insulation 110 to the heat sink with less temperature rise. It is noted that thermal conduction between these components may include thermal conduction between other materials such as brazing material or thermally conductive material (e.g., paste, adhesive, pad, grease, etc.) utilized to couple and / or hold these components together in the assembly.

[0028] FIG. IB shows a side view 120 and thermal profile of the electronic assembly in FIG. 1A. As shown in FIG. IB, the electronic devices 104 are mounted to thermal interface material 106 which is mounted to heat spreader 108. Heat spreader 108 is mounted to heat sink 112 with an electrical insulation 110 positioned between heat spreader 108 and heat sink 112. The thermal stackup (i.e. percentage of thermal contributions) is shown as 122 which includes thermal contribution 122 A from the electronic devices 104 themselves, thermal contribution 122B from the thermal interface material 106, thermal contribution 122C from the heat spreader, thermal contribution 122D from the electrical insulation and mounting layer (e.g., adhesive), thermal contribution 112E from the heatsink and coolant.

[0029] FIG. 1C shows an assembled perspective view 130 of an electronic assembly including a heat spreader 108. Specifically, electronic devices 104 are mounted to thermal interface material 106 which is mounted to heat spreader 108 which is mounted to heat sink 112 via an electrical insulation 110. Mounting of these various devices may include the use of one or more of brazing, thermal paste, and adhesive. It is also noted that electronic devices 104 have electrical pins thatare electrically connected (e.g., soldered) to PCB 102 (not shown). It is shown in FIG. 1C that the assembled electronic assembly provides a larger surface area for thermal contact with the heat sink 112 and also provides a slim profile of the overall assembly. In other words, the thermal stackup ensures that the physical profile of the assembly remains as slim as an approach without the use of a heat spreader, and therefore does not hinder installation of the assembly in the EV. For example, the assembly shown in FIG. 1C may be installed into an energy product such as a slim heat sink panel of the EV. Thus, ensuring a slim profile prevents the assembly from requiring design changes to the EV panel. In other words, the addition of the heat spreader does not affect installation of the assembly.

[0030] The improvement in thermal performance of the assembly due to the addition of the heat spreader is significant. For example, FIG. ID shows a view 140 of a data plot 142 comparing thermal resistance for an electronic assembly heatsink with and without heat spreader 108. In this example, electronic assembly 144 does not include heat spreader 108 but rather connects electronic devices 104 to thermal interface material 106 which is then connected to the heat sink via electrical insulation layer. In contrast, electronic assembly 132 is the electronic assembly shown in FIG. 1C where the electronic devices 104 are connected to the thermal interface material 106, which is connected to heat spreader 108 which is in turn connected to the heat sink via the electrical insulation layer. Due to use of heat spreader 108, it is evident that electronic assembly 132 has lower thermal resistance than electronic assembly 144. It is further evident that the thermal resistance of electronic assembly 132 decreases exponentially with an increase in heat spreader effective radius or square area until eventually plateauing. In other words, thermal resistance decreases as the surface area of the heat spreader increases. The optimal surface area of heat spreader 108 may be chosen to reach a desired percentage of the minimum thermal resistance capable of being achieved by electronic assembly 132. It is noted that the optimal area of heat spreader 108 may be dependent upon various factors such as the types / sizes / shapes / power requirements of electronic devices 104, the material of heat spreader 108, the material of the electrical insulation 110, physical installation limitations, manufacturing methods, etc.

[0031] Assembling of the electronic assembly described above may implement various steps. For example, FIG. IE shows an example flowchart 150 of assemblyprocedures for the electronic assembly including a heat spreader. In step 152, the heat spreader is thermally coupled to the heat sink. This may be a connection via a thin electrical insulation layer in between the heat spreader and heat sink. In step 154, the thermal interface is thermally coupled to the heat spreader. In step 156, the electronic device(s) are connected (e.g., soldered) to the PCB. In step 158, the electronic device(s) are thermally coupled to the thermal interface. The thermal coupling between the electronic device(s), thermal interface material, heat spreader and heat sink may be achieved through thermal adhesive and / or brazing / soldering techniques. It is noted that although the steps are described in a specific sequence, that the sequence may be altered, and certain steps may be performed simultaneously.

[0032] The electronic assembly shown and described with respect to FIGS. 1A- 1E is an example of an electronic assembly where a thermal interface material is used as an interface between the electronic devices and the heat spreader. FIGS. 2A-2F now describe another example of an electronic assembly that also utilizes lamination. Specifically, the heat spreader is laminated to provide electrical insulation while providing openings in the lamination for thermal contact with the electronic devices. In other words, the heat spreader is encapsulated with a laminate having limited openings to accommodate direct thermal and electrical contact with the electronic devices, providing insulated surfaces on opposite sides of the heat spreader. This example may be beneficial for providing additional thermal performance and protection against electrical faults, or for manufacturing multiple heat spreaders in a single assembly, or for using the heat spreader as a conductor of the current passing through the electronic device. For example, when electronic devices are directly connected to the heat spreader, electrical power and / or electrical signals may be conducted between the electronic devices via the heat spreader. This may be beneficial for carrying electrical currents via the heat spreader rather than through the PCB traces. In other words, the electronic devices may be electrically connected to the heat spreader such that the heat spreader may be used as a bus bar for the electronic devices and other devices within the energy product. It is noted that variations of the electronic assembly in FIGS. 1 A-1E are possible. For example, the electronic assembly may include one or more heat spreaders (e.g., one large heat spreader or multiple smaller heat spreaders), one or more electronic devices thermally coupled to the one or moreheat spreaders via thermal interfaces (e.g., thermally conductive adhesive, brazing, etc.), electrical insulation attached to one of the heat spreader or the heat sink or included as a standalone layer sandwiched between the heat spreader and heat sink in the form of laminate, coating, or surface conversion.

[0033] FIG. 2A shows an electronic assembly 200 including an example of a laminated heat spreader. The electronic assembly generally includes electronic devices 204 (e.g., high-voltage, high power, semi-conductor switches) soldered to and possibly (glued, sintered, etc.) to PCB 208 which may have other electrical components such as electrical traces, capacitors, inductors, resistors, etc. (not shown) for supporting operation of the semi-conductor switches. As mentioned above, the semi-conductor switches may form part of an inverter circuit for driving an AC motor of an EV. Also included in the electronic assembly is a laminated heat spreader 202 and heat sink 212. Rather than thermally couple electronic devices 104 directly to heat sink 212, intermediate components are utilized to both spread the heat produced by electronic devices 204 and to electrically insulate electronic devices 204. In one example, laminated heat spreader 202 is a plate of material (e.g., aluminum) for spreading the heat generated by electronic devices 204 to a larger surface area of the heat sink. In this example, a single heat spreader is used for multiple electronic devices 204. However, it is noted that each of the electronic devices 204 may have a separate heat spreader, or more than two electronic devices may share a single heat spreader.

[0034] The components of the assembly are generally connected to other another via brazing, thermal adhesive or a combination of both. For example, electronic devices 204 are thermally coupled (e.g., via thermal adhesive or sintering / soldering) to the metal plate of laminated heat spreader 202 via an opening in the lamination, coating, or surface conversion. In other words, laminated heat spreader 202 includes an opening in the lamination exposing the metal surface of laminated heat spreader 202. This opening is generally formed to the size of the bodies of electronic devices 204. This configuration allows the bodies of electronic devices 204 to directly contact the metal surface of laminated heat spreader 202 using thermal glue, solder, braze material, or any other possible metal-to-metal bonding methods as a thermal interface material while also guarding the electrical connections (e.g., pins) of electronic devices 204 from contacting the metal surface of laminated heat spreader 202. In other words, thelamination acts as an electrical insulator that protects against electrical faults. In addition, the lamination can have good thermal conduction properties and therefore facilitates heat conduction from electronic devices 204 into the metal body of the heat spreader. Once connected to each other, device 206 (i.e., laminated heat spreader 202 and electronic devices 204) can be connected to PCB 208. Specifically, the electrical pins of electronic devices 204 may be soldered to electrical connectors (not shown) on PCB 208. Once complete, device 206 is thermally coupled to heat sink 212. Electrical insulation may or may not be needed since the lamination may act as an electrical insulator. In this example, it is noted that laminated heat spreader 202 is comprised of a metal plate or the like having all surfaces (other than the openings for thermal coupling to the electronic devices) laminated, coated, or converted and therefore electrically insulated. It is also noted that a single opening or multiple openings may be made in the lamination to accommodate the thermal coupling of one or more electronic devices to the metal surface of laminated heat spreader 202.

[0035] As mentioned above, a function of laminated heat spreader 202 in this configuration is to provide both electrical insulation between electronic devices 204 and heat sink 212. These properties are beneficial for properly cooling electronic devices 204 and protecting electronic devices 204 from electrical faults that may occur from inadvertent contact and arcing between components of different voltage potential including grounded chassis components.

[0036] FIG. 2B shows an exploded perspective view 220 of an electronic assembly including a laminated heat spreader. The components in this assembly include PCB 222, electronic devices 224, upper lamination sheet 226 including openings 228 in the lamination, heat spreader 230 and lower lamination sheet 232.

[0037] In this configuration, electronic devices 224 have pins that are soldered to PCB 222. The laminated heat spreader can be formed by a single sheet of laminate or the combination of multiple lamination sheets (e.g., uniform substrates), such as upper lamination sheet 226 and lower lamination sheet 232, and heat spreaders 230 (e.g., metal plates). Specifically, lower lamination sheet 232 can include conforming features such as recessed portions (i.e., depressions) having dimensions for accommodating heat spreaders 230. In other words, lower lamination sheet 232 can be designed and formed to receive heat spreaders 230 in individual recessed portions. Upper lamination sheet 226 can be essentially a flatlamination sheet with openings 228 for exposing limited portions of the metal surfaces of heat spreaders 230. When assembled, heat spreaders 230 can be positioned in the recesses of lower lamination sheet 232. Upper lamination sheet 226 and lower lamination sheet 232 can then be bonded together to form a fully sealed unit (other than openings 228) for electrically insulating individual heat spreaders 230. It is noted that although FIG. 2B shows a configuration with a single device and single heat spreader it is noted that multiple heat spreaders with one or multiple devices each may be individually separated in recesses of the lower lamination sheet 232. In such a design, all electronic devices 204 may be thermally bonded to the same heat spreader assembly but not necessarily the same heats preader. In other examples without recessed portions, both laminate sheets may be flat.

[0038] FIG. 2C shows a side view and thermal profile 240 of the electronic assembly in FIG. 2B. As shown in FIG. 2C, the electronic device 241 are mounted, via thermal interface 242, to a laminated heat spreader 244 laminated between an upper lamination sheet 243 and a lower lamination sheet 245. It is noted that thermal interface 242 is optional and, in some examples, electronic device 241 is mounted directly to laminated heat spreader 244. The laminated heat spreader is in turn mounted to heat sink 247 via adhesive 246. The thermal stackup (i.e., percentage of thermal contributions) is shown as 248 which includes thermal contribution 248 A from the electronic device 241 itself, thermal contribution 248B from the thermal interface, thermal contribution 248C from the heat spreader, thermal contribution 248D from the lower lamination sheet 245, thermal contribution 248E from the adhesive 246, and thermal contribution 248F from the coolant and heat sink 247. It is noted that the thermal stackup contributions are merely examples and may vary depending on materials utilized, dimensions of devices, configurations of devices, etc.

[0039] FIG. 2D shows an assembled perspective view of a laminated heat spreader module 250. In this view, heat spreaders 230 are laminated between upper lamination sheet 226 and lower lamination sheet 232 to form a lamination 252 with heat spreaders 230 therebetween. It is noted that lamination 252 also includes openings 256 that expose the metal surfaces of heat spreaders 230. These openings are positioned and sized according to the position and size of electronicdevices 224 on the PCB. In general, the sizes / shapes of the openings coincide with the size / shapes of the bodies of the electronic devices 224.

[0040] FIG. 2E shows an assembled side view 260 of the laminated heat spreader as shown in FIG. 2D. In this view, the heat spreaders are positioned in lamination recesses 254 and covered with lamination 252. In another example, heat spreaders 230 may be replaced by a single large heat spreader (not shown), where the openings allow the electronic devices to be thermally coupled to different regions of the single large heat spreader. It is noted that variations of the electronic assembly in FIGS. 2A-2E are possible. For example, the electronic assembly may include one or more heat spreaders (e.g., one large heat spreader or multiple smaller heat spreaders), one or more electronic devices thermally coupled to the one or more heat spreaders via thermal interfaces (e.g., thermally conductive adhesive, brazing, etc.), lamination including a top layer with one or more openings for allowing the one or more electronic devices thermally coupled to the one or more heat spreaders and a bottom layer providing electrical insulation between the one or more heat spreaders and the heat sink.

[0041] FIG. 2F shows a flowchart 270 of assembly procedures for the electronic assembly including a laminated heat spreader. In step 272, the heat spreader (one or more metal plates) is laminated between a lower lamination layer and an upper lamination layer. The one or more metal plates may be an aluminum plate or any material that provides sufficient thermal conductance. The layers of the heat spreader may be formed separately and then attached together (e.g., via adhesive, heat welding, etc.) to form a lamination housing that completely covers (i.e., encapsulates) the heat spreader(s) with the exception of one or more openings for thermally coupling the electronic devices to the metal surface of the heat spreader(s). In one example, the laminate layers may be molded over the heat spreader plates. In another example, the laminate layers may be molded separately and then fused / adhered together to encapsulate the heat spreader plates. Additionally, the electrical insulation may also be formed as a coating or surface conversion in place of the laminate. In step 274, the lower layer of the electrically insulated heat spreaders is thermally coupled to the heat sink surface. For example, the electrically insulated heat spreaders may be adhered to the exposed surface of the heat sink via thermally conductive adhesive. In step 276, the electronic devices are soldered to the PCB connectors to form part of a circuit(e.g., inverter circuit). In step 278, the body of the electronic devices are thermally coupled to the heat spreader surfaces through the openings in the electrical insulation. These openings may be designed to accommodate the shape and dimensions of the electronic devices. The thermal coupling between the electronic device(s), electrically insulated heat spreader and heat sink may be achieved through thermal adhesive and / or brazing, soldering, sintering or other metal-to- metal bonding techniques. It is noted that although the steps are described in a specific sequence, that the sequence may be altered, and certain steps may be performed simultaneously. It is also noted that the upper and lower lamination layers may be formed as a single monolithic lamination layer. For example, the heat spreaders (metal plate(s)) may be positioned into a mold where the lamination material is injected as a liquid to form the lamination structure shown in FIG. 2F. In other words, the upper and lower lamination layers may be solidified to form a monolithic lamination structure encapsulating the heat spreaders with the exception of the predetermined openings for receiving the electronic devices.

[0042] EVs utilizes one or more electronic assemblies comprising high-voltage, high-power, electronic devices (e.g., power switches) for driving an electric motor of the EV drivetrain. These electronic assemblies are generally mounted in a panel configuration. FIG. 3A shows an exploded perspective view 300 of an electronic assembly including a laminated heat spreader installed on a panel. Panel 302 (large heat sink) may be located in various locations of the vehicle including but not limited to the powertrain housing, chassis area, and battery compartment of the EV. The primary components of panel 302 can include one or more panels and components including but not limited to top sheet 302 A with clinch hardware for connection of panel 302 to other EV structures, and a heat sink comprising middle sheet 302B, cooling fins 302C, and bottom sheet 302D that when combined act as a sealed coolant path where coolant flows through cooling fins 302C thereby absorbing the heat conducting through middle sheet 302B and bottom sheet 302D and expelling the heat through a coolant system (e.g., radiator) of the EV not shown.

[0043] In this configuration, laminated heat spreader module 250 can be thermally coupled to middle sheet 302B via thermal adhesive or the like, and top sheet 302 A is mounted to middle sheet 302B thereby holding heat spreader module 250 in a predetermined position. It is noted that top sheet 302A has openings for nestingheat spreaders into the sheet and allowing access for electronic devices (not shown) to be thermally coupled to the metal surfaces of the heat spreaders in heat spreader module 250. To complete the assembly, bottom sheet 302D of the heat sink is mounted to middle sheet 302B of the heat sink with cooling fins positioned therebetween. As mentioned above, the cooling fins may be connected to a fluid coolant system to absorb and expel heat generated by the electronic components. In other words, heat generated by the electronic components can be absorbed into the heat spreaders, transferred to middle sheet 302B of the heat sink, bottom sheet 302D of the heat sink, and cooling fins 302C. Fluid running through cooling fins 302C can absorb the heat of the assembly and expel the heat through a coolant system of the EV. This coolant system may include fluid tubes / pipes, a coolant pump and a radiator located in the front grill area of the EV. It is noted that the flow of the coolant may also cool other EV components such as the EV battery and powertrain (e.g., motor, bearings, etc.).

[0044] It is noted that although the heat spreader assembly is beneficial for EV cooling applications, the heat spreader assembly solution may also be useful in other applications of an energy products that require cooling of electronic devices. These applications may include but are not limited to cooling electronic components of other types of EVs (e.g., aerial EVs, aquatic EVs, etc.). The applications may also include non-EV applications of energy products (e.g., household power systems that utilize inverters to convert DC from batteries to AC to power homes, etc.). In general, the heat spreader assembly solution can be used in any application that requires cooling of electronic devices at voltage potentials different than their coupled heatsinks.

[0045] FIG. 3B shows a flowchart 310 of assembly procedures for the electronic assembly including a laminated heat spreader installed in a panel. In step 312, the heat spreader is laminated to form laminated heat spreader module 250. This lamination process may include creating separate lamination sheets (upper / lower sheets) and fusing the sheets together using adhesive or heat. Alternatively, the lamination process may include creating a monolithic lamination sheet via injection molding. For example, the heat spreader plates (e.g., metal plates) may be placed into a mold, and then the lamination material is injected into the mold to encapsulate the metal plates with the exception of predefined openings for accommodating the electronic components. In step 314, the laminated heatspreader module 250 is thermally coupled to middle sheet 302B of the heat sink. In step 316, the top sheet 302A is positioned over the laminated heat spreader module 250 such that laminated heat spreader module 250 is exposed through openings in top sheet 302 A. Top sheets 302 A and middle sheet 302B may be connected together via fasteners, brazing or the like such that laminated heat spreader module 250 is affixed in a specific location between the sheets using such features for precise location. In step 318, the electronic devices are soldered to the PCB. This soldering process may result in multiple electronic devices soldered to one or more PCBs, and the multiple electronic devices being thermally coupled to one or more laminated heat spreader modules 250. In step 320, the bodies of the electronic devices are thermally coupled to the exposed metal surfaces of the heat spreaders through the openings in the lamination. As mentioned above, these openings may have shapes and dimensions specifically designed for receiving the electronic devices having specific shapes and dimensions. The thermal coupling between the electronic device(s), any thermal interface material, heat spreader, and heat sink may be achieved through thermal adhesive and / or brazing, soldering, sintering, or other metal bonding techniques. It is noted that although the steps are described in a specific sequence, that the sequence may be altered, and certain steps may be performed simultaneously.

[0046] While the foregoing is directed to examples described herein, other and further examples may be devised without departing from the basic scope thereof. It will be appreciated by those skilled in the art that the preceding examples are exemplary and not limiting. It is intended that all permutations, enhancements, equivalents, and improvements thereto are apparent to those skilled in the art upon a reading of the specification and a study of the drawings are included within the true spirit and scope of the present disclosure. It is therefore intended that the following appended claims include all such modifications, permutations, and equivalents as fall within the true spirit and scope of these teachings.EXAMPLES

[0047] Thus, some examples may include one or more of the following:

[0048] Example 1 is an electronic assembly comprising a heat spreader comprising a thermally conductive plate comprising a first insulated surface and a second insulated surface, the first insulated surface and the second insulatedsurface located on opposite sides of the thermally conductive plate, the first insulated surface comprising an opening exposing the thermally conductive plate, and an electronic device comprising a body and electrical connections, the body of the electronic device thermally coupled to the thermally conductive plate through the opening.

[0049] In Example 2, the subject matter of Example 1 comprises a printed circuit board (PCB) electrically connected to the electrical connections of the electronic device.

[0050] In Example 3, the subject matter of Examples 1-2 a heat sink thermally coupled to the second insulated surface of the heat spreader.

[0051] In Example 4, the subject matter of Examples 1-3 comprises wherein the first insulated surface and the second insulated surface are at least one of an insulated lamination, an insulated coating or an insulated surface conversion.

[0052] In Example 5, the subject matter of Example 4 comprises wherein the body of the electronic device is thermally coupled to the thermally conductive plate by thermally conductive material, and the heat sink is thermally coupled to the second insulated surface of the heat spreader by the thermal material.

[0053] In Example 6, the subject matter of Examples 1-5 comprises wherein a laminate of the first insulated surface and the second insulated surface is comprised of material that provides electrical insulation between the electrical connections of the electronic device and the thermally conductive plate, and electrical insulation between the thermally conductive plate and the heatsink.

[0054] In Example 7, the subject matter of Examples 1-6 comprises wherein the electronic device is a high-power semi-conductor switch.

[0055] In Example 8, the subject matter of Examples 1-7 comprises an additional heat spreader comprising an additional thermally conductive plate comprising a third insulated surface and a fourth insulated surface, the third insulated surface and the fourth insulated surface located on opposite sides of the additional thermally conductive plate, the third insulated surface comprising an additional opening exposing the additional thermally conductive plate, and an additional electronic device comprising an additional body and additional electrical connections, the additional body of the additional electronic device thermally coupled to the additional thermally conductive plate through the additional opening, wherein the first insulated surface and the third insulated surface comprise a first uniform substrate of laminate, and the second insulatedsurface and the fourth insulated surface comprise a second uniform substrate of laminate.

[0056] In Example 9, the subject matter of Examples 1-8 comprises an additional electronic device comprising an additional body and additional electrical connections, the additional body of the additional electronic device thermally coupled to the thermally conductive plate through an additional opening in the first insulated surface.

[0057] In Example 10, the subject matter of Examples 1-9 comprises wherein the second insulated surface comprises a substrate of laminate comprising a depression for receiving the thermally conductive plate.

[0058] Example 11 is a method comprising: laminating a heat spreader to form a laminated heat spreader module; thermally coupling the laminated heat spreader module to a middle sheet of a heat sink; positioning a top sheet over the laminated heat spreader module, the laminated heat spreader module exposed through one or more openings in the top sheet; and thermally coupling one or more electronic devices to the laminated heat spreader module through the one or more openings in the top sheet.

[0059] In Example 12, the subject matter of Example 11 comprises fusing an upper lamination sheet and a lower lamination sheet together using adhesive or heat.

[0060] In Example 13, the subject matter of Examples 11-12 comprises wherein the top sheet and the middle sheet are connected by fasteners or brazing.

[0061] In Example 14, the subject matter of Examples 11-13 comprises wherein the one or more openings have first shapes and first dimensions corresponding with second shapes and second dimensions of the one or more electronic devices.

[0062] Example 15 is a panel comprising: a heat spreader comprising a thermally conductive plate comprising a first surface and a second surface, the first surface and the second surface located on opposite sides of the thermally conductive plate; a thermal interface thermally coupled to the first surface of the thermally conductive plate; and a power switch thermally coupled to the thermal interface.

[0063] Example 16 is an electronic assembly comprising a heat spreader comprising a thermally conductive plate comprising a first surface and a second surface, the first surface and the second surface located on opposite sides of thethermally conductive plate, a thermal interface thermally coupled to the first surface of the thermally conductive plate, and an electronic device comprising a body and electrical connections, the body of the electronic device thermally coupled to the thermal interface.

[0064] In Example 17, the subject matter of Example 16 comprises a printed circuit board (PCB) electrically connected to the electrical connections of the electronic device.

[0065] In Example 18, the subject matter of Examples 16-17 comprises a heat sink thermally coupled to the second surface of the heat spreader.

[0066] In Example 19, the subject matter of Example 18 comprises an insulation layer positioned between the heat sink and the heat spreader.

[0067] In Example 20, the subject matter of Example 19 comprises wherein the body of the electronic device is thermally coupled to the thermal interface by thermally conductive material, and the heat sink is thermally coupled to the second surface of the heat spreader by the thermal material.

[0068] In Example 21, the subject matter of Examples 16-20 comprises wherein the thermal interface is comprised of material that provides electrical insulation between the electrical connections of the electronic device and the thermally conductive plate, and provides thermal conduction between the body of the electronic device and the thermally conductive plate.

[0069] In Example 22, the subject matter of Examples 16-21 comprises the electronic device is a high-power semi-conductor switch.

[0070] In Example 23, the subject matter of Examples 16-22 comprises an additional thermal interface thermally coupled to the first surface of the thermally conductive plate, and an additional electronic device comprising an additional body and additional electrical connections, the additional body of the additional electronic device thermally coupled to the additional thermal interface.

[0071] In Example 24, the subject matter of Examples 16-23 comprises an additional electronic device comprising an additional body and additional electrical connections, the additional body of the additional electronic device thermally coupled to the thermal interface.

[0072] In Example 25, the subject matter of Examples 16-24 comprises wherein the thermal interface comprises dimensions corresponding to dimensions of the electronic device.

[0073] It should be noted that the description and the figures above merely illustrate the principles of the present subject matter along with examples described herein and should not be construed as a limitation to the present subject matter. It is thus understood that various arrangements may be devised that although not explicitly described or shown herein, embody the principles of the present subject matter. Moreover, all statements herein reciting principles, aspects, and implementations of the present subject matter, as well as specific examples thereof, are intended to encompass equivalents thereof.

[0074] It is to be understood that not necessarily all objects or improvements may be achieved in accordance with any particular example described herein. Thus, for example, those skilled in the art will recognize that some examples may be operated in a manner that achieves or optimizes one characteristic or group of characteristics as taught herein without necessarily achieving other objects or characteristics as may be taught or suggested herein.

[0075] All of the processes described herein may be embodied in, and fully automated via, software code modules executed by a computing system that includes computers or processors. The code modules may be stored in any type of non-transitory computer-readable medium or other computer storage device. Some or all of the methods may be embodied in specialized computer hardware.

[0076] Many other variations than those described herein will be apparent from this disclosure. For example, depending on the example, some acts, events, or functions of any of the algorithms described herein can be performed in a different sequence, can be added, merged, or left out altogether (for example, not all described acts or events are necessary for the practice of the algorithms). Moreover, in some examples, acts or events can be performed concurrently, for example, through multi-threaded processing, interrupt processing, or multiple processors or processor cores, or on other parallel architectures, rather than sequentially. In addition, different tasks or processes can be performed by different machines and / or computing systems that can function together.

[0077] The various illustrative logical blocks and modules described in connection with the examples disclosed herein can be implemented or performed by a machine, such as a processing unit or processor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A processor can be a microprocessor, but in the alternative, the processor can be a controller, microcontroller, or state machine, combination of the same, or the like. A processor can include electrical circuitry to process computerexecutable instructions. In some examples, a processor includes an FPGA or other programmable device that performs logic operations without processing computer-executable instructions. A processor can also be implemented as a combination of computing devices, for example, a combination of a DSP and a microprocessor, a plurality of microprocessors, microprocessors in conjunction with a DSP core, or any other such configuration.

[0078] Although described herein primarily with respect to digital technology, a processor may also include primarily analog components. A computing environment can include any type of computer system, including, but not limited to, a computer system based on a microprocessor, a mainframe computer, a digital signal processor, a portable computing device, a device controller, or a computational engine within an appliance, to name a few. The elements of a method, process, routine, or algorithm described in connection with the examples disclosed herein can be embodied directly in hardware, in a software module executed by a processor device, or in a combination of the two. A software module can reside in RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, hard disk, a removable disk, a CD-ROM, or any other form of a non-transitory computer-readable storage medium. An example storage medium can be coupled to the processor device such that the processor device can read information from, and write information to, the storage medium. In the alternative, the storage medium can be integral to the processor device. The processor device and the storage medium can reside in an ASIC. The ASIC can reside in a user terminal. In thealternative, the processor device and the storage medium can reside as discrete components in a user terminal.

[0079] The processes described herein or illustrated in the figures of the present disclosure may begin in response to an event, such as on a predetermined or dynamically determined schedule, on demand when initiated by a user or system administrator, or in response to some other event. When such processes are initiated, a set of executable program instructions stored on one or more non-transitory computer-readable media (e.g., hard drive, flash memory, removable media, etc.) may be loaded into memory (e.g., RAM) of a server or other computing device. The executable instructions may then be executed by a hardware-based computer processor of the computing device. In some examples, such processes or portions thereof may be implemented on multiple computing devices and / or multiple processors, serially or in parallel.

[0080] Although the described flow diagrams herein can show operations as a sequential process, many of the operations can be performed in parallel or concurrently. In addition, the order of the operations may be re-arranged. A process is terminated when its operations are completed. A process may correspond to a method, a procedure, an algorithm, etc. The operations of methods may be performed in whole or in part, may be performed in conjunction with some or all of the operations in other methods, and may be performed by any number of different systems, such as the systems described herein, or any portion thereof, such as a processor included in any of the systems.

[0081] Conditional language such as, among others, “can,” “could,” “might” or “may,” unless specifically stated otherwise, are otherwise understood within the context as used in general to convey that some examples include, while other examples do not include, some features, elements and / or steps. Thus, such conditional language is not generally intended to imply that features, elements and / or steps are in any way for examples or that examples necessarily include logic for deciding, with or without user input or prompting, whether these features, elements and / or steps are included or are to be performed in any particular example.

[0082] Disjunctive language such as the phrase “at least one of X, Y, or Z,” unless specifically stated otherwise, is otherwise understood with the context as used in general to present that an item, term, etc., may be either X, Y, or Z, or any combination thereof (for example, X, Y, and / or Z). Thus, such disjunctive language is not generally intended to, and should not, imply that some examples require at least one of X, at least one of Y, or at least one of Z to each be present.

[0083] Any process descriptions, elements or blocks in the flow diagrams described herein and / or depicted in the attached figures should be understood as potentially representing modules, segments, or portions of code which include executable instructions for implementing specific logical functions or elements in the process. Alternate examples are included within the scope of the examples described herein in which elements or functions may be deleted, executed out of order from that shown, or discussed, including substantially, concurrently, or in reverse order, depending on the functionality involved as would be understood by those skilled in the art.

[0084] It should be emphasized that many variations and modifications may be made to the above-described examples, the elements of which are to be understood as being among other acceptable examples. All such modifications and variations are intended to be included herein within the scope of this disclosure.

[0085] Any process descriptions, elements or blocks in the flow diagrams described herein and / or depicted in the attached figures should be understood as potentially representing modules, segments, or portions of code which include executable instructions for implementing specific logical functions or elements in the process. Alternate implementations are included within the scope of the examples described herein in which elements or functions may be deleted, executed out of order from that shown, or discussed, including substantially concurrently or in reverse order, depending on the functionality involved as would be understood by those skilled in the art.

[0086] Unless otherwise explicitly stated, articles such as “a” or “an” should generally be interpreted to include one or more described items. Accordingly, phrases such as “a device configured to” are intended toinclude one or more recited devices. Such one or more recited devices can also be collectively configured to carry out the stated recitations. For example, “a processor configured to carry out recitations A, B, and C” can include a first processor configured to carry out recitation A working in conjunction with a second processor configured to carry out recitations B and C.

[0087] It will also be appreciated that one or more of the elements depicted in the drawings / figures can also be implemented in a more separated or integrated manner, or even removed or rendered as inoperable in certain cases, as is useful in accordance with a particular application.

[0088]

Claims

CLAIMS1. An electronic assembly comprising: a heat spreader comprising a thermally conductive plate comprising a first insulated surface and a second insulated surface, the first insulated surface and the second insulated surface located on opposite sides of the thermally conductive plate, the first insulated surface comprising an opening exposing the thermally conductive plate; and an electronic device comprising a body and electrical connections, the body of the electronic device thermally coupled to the thermally conductive plate through the opening.

2. The electronic assembly of claim 1, further comprising: a printed circuit board (PCB) electrically connected to the electrical connections of the electronic device.

3. The electronic assembly of claim 1, further comprising: a heat sink thermally coupled to the second insulated surface of the heat spreader.

4. The electronic assembly of claim 1, wherein the first insulated surface and the second insulated surface are at least one of an insulated lamination, an insulated coating or an insulated surface conversion.

5. The electronic assembly of claim 3, wherein the body of the electronic device is thermally coupled to the thermally conductive plate by thermally conductive material or direct bonding method, and the heat sink is thermally coupled to the second insulated surface of the heat spreader by the thermally conductive material.

6. The electronic assembly of claim 1, wherein a laminate of the first insulated surface and the second insulated surface is comprised of material that provides electrical insulation between the electrical connections of the electronic device and the thermally conductive plate, and electrical isolation between the thermally conductive plate and heatsink.

7. The electronic assembly of claim 1, wherein the electronic device is a high-power semi-conductor switch.

8. The electronic assembly of claim 1 comprises: an additional heat spreader comprising an additional thermally conductive plate comprising a third insulated surface and a fourth insulated surface, the third insulated surface and the fourth insulated surface located on opposite sides of the additional thermally conductive plate, the third insulated surface comprising an additional opening exposing the additional thermally conductive plate; and an additional electronic device comprising an additional body and additional electrical connections, the additional body of the additional electronic device thermally coupled to the additional thermally conductive plate through the additional opening, wherein the first insulated surface and the third insulated surface comprise a first uniform substrate of laminate, and the second insulated surface and the fourth insulated surface comprise a second uniform substrate of laminate.

9. The electronic assembly of claim 1 comprises: an additional electronic device comprising an additional body and additional electrical connections, the additional body of the additional electronic device thermally coupled to the thermally conductive plate through an additional opening in the first insulated surface.

10. The electronic assembly of claim 1, wherein the second insulated surface comprises a substrate of laminate comprising a depression for receiving the thermally conductive plate.

11. A method comprising: laminating a heat spreader to form a laminated heat spreader module; thermally coupling the laminated heat spreader module to a middle sheet of a heat sink; positioning a top sheet over the laminated heat spreader module, the laminated heat spreader module exposed through one or more openings in the top sheet; andthermally coupling one or more electronic devices to the laminated heat spreader module through the one or more openings in the top sheet.

12. The method of claim 11, wherein laminating the heat spreader comprises: fusing an upper lamination sheet and a lower lamination sheet together using adhesive or heat.

13. The method of claim 11, wherein the top sheet and the middle sheet are connected by fasteners or brazing.

14. The method of claim 11, wherein the one or more openings have first shapes and first dimensions corresponding with second shapes and second dimensions of the one or more electronic devices.

15. A panel comprising: a heat spreader comprising a thermally conductive plate comprising a first surface and a second surface, the first surface and the second surface located on opposite sides of the thermally conductive plate; a thermal interface thermally coupled to the first surface of the thermally conductive plate; and a power switch thermally coupled to the thermal interface.

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