COLD PLATE HAVING OPENING AND RELATED SYSTEMS

Electronic assemblies with a cold plate having an opening are provided. In one aspect. a system includes an array of electronic components. a control board. and a cold plate having a plurality of openings therethrough. The cold plate can be arranged between the array of electronic components and the control board. The cold plate can cool the array of electronic components. The system can also include a plurality of pass through connectors arranged in the openings in the cold plate and configured to connect the array of electronic components to the control board. The cold plate can also be used to cool the control board electronics and the connectors passing through.

BACKGROUND

Technological Field

The present disclosure relates generally to cooling components and electronic assemblies with a cooling component.

Description of the Related Technology

A system on a wafer (SoW) assembly can include a SoW and a heat dissipation structure coupled to the SoW. In some applications, a SoW can include voltage regulating modules (VRMs) and a thermal interface material between the heat dissipation structure and the SoW. A cold plate can be positioned near to the VRMs to cool the VRMs during operation. There are technical challenges related to implementing a cold plate in an electronic assembly with limited area while also providing a desired amount of cooling.

SUMMARY OF CERTAIN INVENTIVE ASPECTS

In one aspect, there is provided a system, comprising: an array of electronic components; a printed circuit board assembly; a cold plate having a plurality of openings therethrough, the cold plate arranged between the array of electronic components and the printed circuit board assembly, and the cold plate configured to cool the array of electronic components; and a plurality of pass through connectors arranged in the openings of the cold plate and configured to connect the array of electronic components to the printed circuit board assembly.

In some embodiments, the cold plate comprises a cold plate body including an array of cooling elements, each of the cooling elements is configured to cool at least one of the electronic components, and each of the cooling elements houses a set of fins.

In some embodiments, the cold plate further comprises an inlet port configured to receive a coolant and an outlet port configured to discharge the coolant.

In some embodiments, the cold plate further comprises: an inlet manifold connected to the inlet port, an outlet manifold connected to the outlet port, and a plurality of flow channels connecting the inlet manifold to the cold plate body and the cold plate body to the outlet manifold.

In some embodiments, the cooling elements are arranged in a plurality of parallel coolant flow paths, each of the flow channels is connected to the cold plate body via a corresponding orifice, and each of the orifices has a diameter to provide a substantially equal flow rate through the parallel coolant flow paths.

In some embodiments, the inlet manifold and the outlet manifold are arranged in a different plane than the cold plate body.

In some embodiments, the fins are arranged in one of the following configurations: in parallel, serpentine, cylindrical, or staggered.

In some embodiments, the pass through connectors comprise pogo pins.

In some embodiments, the pass through connectors are further configured to provide one or more of electrical, thermal, or communication conductivity between the array of electronic components and the printed circuit board assembly.

In some embodiments, the electronic components are voltage regulating modules (VRMs).

In some embodiments, the printed circuit board assembly comprises an array of integrated circuit dies, and the pass through connectors are further configured to connect the array of integrated circuit dies to the array of voltage regulating modules.

In another aspect, there is provided a cold plate for cooling an array of electronic components, the cold plate comprising: a body including an array of cooling elements, wherein the body has a plurality of openings formed therethrough, and each of the openings is configured to receive at least one pass through connector; an inlet port configured to receive a coolant; an inlet manifold configured to receive the coolant from the inlet port; a plurality of inlet channels configured to route the coolant from the inlet manifold to the body; an outlet port configured to discharge the coolant; an outlet manifold configured to route the coolant to the outlet port, and a plurality of outlet channels configured to route the coolant from the body to the outlet manifold.

In some embodiments, the inlet manifold and the outlet manifold are arranged in a different plane than the body.

In yet another aspect, there is provided a cold plate for cooling an array of electronic components, the cold plate comprising: a body including an array of cooling elements, wherein the body has a plurality of openings formed therethrough, and each of the openings is configured to receive at least one pass through connector; an inlet port configured to receive a coolant and provide the coolant to the body; and an outlet port configured to discharge the coolant from the body.

In some embodiments, the cold plate further comprises: an inlet manifold configured to receive the coolant from the inlet port; a plurality of inlet channels configured to route the coolant from the inlet manifold to the body; an outlet manifold configured to route the coolant to the outlet port; and a plurality of outlet channels configured to route the coolant from the body to the outlet manifold, wherein the inlet manifold and the outlet manifold are arranged in a different plane than the body.

In some embodiments, each of the cooling elements is configured to cool a corresponding electronic component arranged adjacent to the cooling element.

In some embodiments, each of the cooling elements houses a set of fins configured to increase heat transfer to the coolant.

In some embodiments, the fins are arranged in one of the following configurations: in parallel, serpentine, cylindrical, or staggered.

In some embodiments, the cooling elements are arranged in a plurality of parallel coolant flow paths, each of the inlet channels is connected to the body via a corresponding orifice, and each of the orifices has a diameter to provide a substantially equal flow rate through the parallel coolant flow paths.

In still yet another aspect, there is provided a system comprising: an electronic component;a cold plate having an opening therethrough and configured to cool the electronic component; and a pass through connector extending through the opening and electrically connected to the electronic component.

In some embodiments, the system further comprises: a printed circuit board assembly arranged such that the cold plate is positioned between the electronic component and the printed circuit board assembly, wherein the pass through connector is configured to electrically connect the electronic component to the printed circuit board assembly.

In some embodiments, the pass through connectors comprise pogo pins.

In some embodiments, the cold plate houses a set of fins.

DETAILED DESCRIPTION

The following detailed description of certain embodiments presents various descriptions of specific embodiments. However, the innovations described herein can be embodied in a multitude of different ways, for example, as defined and covered by the claims. In this description, reference is made to the drawings where like reference numerals and/or terms can indicate identical or functionally similar elements. It will be understood that elements illustrated in the figures are not necessarily drawn to scale. Moreover, it will be understood that certain embodiments can include more elements than illustrated in a drawing and/or a subset of the elements illustrated in a drawing. Further, some embodiments can incorporate any suitable combination of features from two or more drawings. The headings provided herein are for convenience only and are not intended to affect the meaning or scope of the claims.

Electrical Connections in Electronic Assemblies

System on a wafer (SoW) assemblies are examples of electronic assemblies. SoW assemblies can include a SoW and a cooling system that is coupled to the SoW. The SoW can include an array of integrated circuit dies. The SoW assembly can include a wafer level packaging structure. The SoW and the cooling system can include an array of electronic components or modules, such as voltage regulating modules (VRMs), positioned therebetween. A thermal interface material (TIM) can be positioned between the electronic components and the cooling system. As discussed below, the cooling system can include a cold plate configured to cool the VRMs.

One or more aspects of the present application correspond to a two-sided cold plate with power and signal delivery systems. Coolant that flows through the microchannels inside the cold plate can enable cooling high power components on both sides of the cold plate. In some embodiments, the cold plate can implement or otherwise incorporate openings or slots that can accommodate pass through connectors, such compliant connectors (e.g., as pogo pins, flexible pins, spring contacts, etc.), sockets and plugs, and/or male and female connectors. Such connectors can be embedded in a housing or magazine that can be press fit in the slots in the cold plate. The assembly method and form factor of pins-as well as their number and dimension-can vary depending on the implementation. The connectors can be used to transfer power and/or data signals through the cold plate between electronic components. In certain embodiments, the cold plate includes inlet and outlet coolant manifolds on two ends.

Cold plates disclosed herein can provide liquid cooling to electronic components on opposing sides of a respective cold plate. For example, a cold plate can provide cooling to both voltage regulating modules on one side of the cold plate and electronic components on a control board on an opposite side of the cold plate. Such a cold plate can also cool pass though connectors between the electronic components on opposing sides, where the pass though connectors are positioned in openings in the cold plate. Cold plates disclosed herein can provide structural stiffness and/or rigidity to a central region of a system on a wafer assembly. Cold plates disclosed herein can be used to cool arrays of electronic components on opposing sides in certain applications. A cold plate in accordance with any suitable principles and advantages disclosed herein can cool an individual electronic component on each opposing side.

FIG.1is a schematic cross sectional side view of a system on a wafer (SoW) assembly10coupled to a cold plate200with VRMs16on a SoW14on one side and a control board20on another side.FIG.2shows an exploded perspective view of a cold plate200in accordance with aspects of this disclosure. In some implementations, the cold plate200may be inverted compared to the illustrated view when installed in an electronic assembly10.

As illustrated inFIG.1, the SoW assembly10includes a heat dissipation structure12, the SoW14, VRMs16, the cold plate200, and the control board20. The heat dissipation structure12can be a heat sink, a heat spreader, or any other suitable structure to dissipate heat. In some embodiments, the SoW assembly10can further include a TIM (not illustrated) between the cold plate200and the VRMs16. The SoW14can include an array of integrated circuit dies. A VRM16can covert a high voltage, low current to a lower voltage level at a higher current to provide a power supply voltage for an integrated circuit die of the SoW14. The array of VRMs16is one example of an array of electronic components that can be arranged as shown inFIG.1. The arrangement ofFIG.1can be applied to a variety of different electronic components.

The control board20can include an array of electronic components22. The control board is an example of a printed circuit board (PCB). InFIG.1, a printed circuit board assembly includes the control board20and the electronic components22. The electronic components22can be control circuits, each configured to control a corresponding one of the VRMs16. For example, the electronic components22can be configured to provide power and/or control signals to the corresponding VRMs16to operate the VRMs16. The cold plate200can include a plurality of openings with pass through connectors24therein. The pass through connectors24can be pogo pins, for example. With the pass through connectors24extending through openings in the cold plate200, the pass though connectors24can be included in a central area of the SoW assembly10. As illustrated, the pass though connectors24can be positioned in respective areas corresponding to each integrated circuit die of the SoW14.

The pass through connectors24can electrically connect the electronic components22on the control board20to the VRMs16. For example, each of the openings in the cold plate200can be configured to receive a plurality of pass through connectors24, which may be housed in a housing such as a cartridge. The pass through connectors24can be configured to connect electric components arranged on opposite sides of the cold plate200in order to provide power and/or control signals therebetween.

Cold Plate Designs for Electronic Assemblies

In accordance with more aspects of the present application, the structure of the cold plate200of the present application can allow for concurrent efficient cooling and data/power delivery, which enables a compact design. Certain applications have demanding space specifications, such that any space savings within the footprint of the assembly that can be leveraged to improve processing capabilities. For example, in the VRM context, with more of the footprint used by the array VRMs rather than other components, greater compute density and/or processing power can be achieved.

Certain SoW assemblies provide separate physical area on the board for power delivery and/or signal transfer. However, such designs have either (1) limited the cold plate size, which would typically affect the thermal performance and supported power negatively, consequently limiting the overall performance of the system; and/or (2) increased the board area, which would affect the volume efficiency and compactness of the system. Avoiding an increase in the board size can prevent reduced performance due to increased compute latency associated with larger board size. Aspects of this disclosure can solve at least some of these problems by providing cooling as well as power delivery and/or signal transfer though a cold plate without limiting the cold plate size and/or increasing the board area.

Although aspects of this disclosure are described in connection with a SoW assembly10including a plurality of VRMs, this disclosure can also be employed in other applications, such as for dense servers, mezzanine boards, etc.

With reference now toFIG.2, an embodiment of the cold plate200of the present application will be described. The illustrated cold plate200includes an inlet port202, inlet manifold204, mechanical supports206, flow channels208, a body209, fins210within the body209, outlet manifold212, and an outlet port214. The cold plate200also includes openings216(also referred to as receptacles or slots) for pass through connectors (e.g., pogo pins) that provide for thermal, power, and/or communication connectivity through the cold plate200. In some implementations, the cold plate body209may be formed of machined copper parts that have been brazed. The cold plate body209can be formed of any other suitable material. The cold plate body209can include an array of cooling elements400(e.g., as labeled inFIG.3), each of which encloses one set of fins210.

FIG.3is a plan view illustrating the flow of coolant218through the cold plate200ofFIG.2in accordance with aspects of this disclosure. As shown inFIG.3, in some implementations the cold plate200can form a plurality of parallel coolant flow paths220through which coolant218the can flow. The arrows for the parallel coolant flow paths220indicate the general direction of coolant flow, although coolant may flow through corners of cooling elements400when flowing between adjacent cooling elements400in a coolant flow path. The coolant flow from the inlet port202to the outlet port214can be controlled for substantially equal distribution using different orifice sizes (seeFIGS.6A and6B). The inlet manifold204together with the flow channels208can provide a substantially equal flow of coolant to each of the coolant flow paths220. The coolant218is gradually heated as the coolant cools the adjacent electronic components by flowing through the fins210(seeFIG.2). The outlet manifold212can route coolant218to the output port214. The coolant218can be discharged from the outlet port214.

FIG.3also illustrates how the body209of the cold plate200is formed as an array of cooling elements400. With reference toFIGS.2and3, each cooling element400includes a portion of the body209that defines a volume housing fins210. In addition, each cooling element400is fluidly connected to its adjacent cooling element(s)400in the same coolant flow path220near the corners of the cooling elements400such that the coolant218flows around the openings216in the cold plate200.

FIGS.4A-4Dillustrate the cold plate200in various stages of system assembly with additional components attached thereto.FIG.4Aillustrates the assembled cold plate200,FIG.4Billustrates the cold plate200with dripless quick disconnects attached to the inlet and outlet,FIG.4Cillustrates connector assemblies installed into the openings in the cold plate200, andFIG.4Dillustrates a control board attached to one side of the cold plate200.

With reference toFIGS.4A-4D, dripless quick disconnects302can be respectively attached to each of the inlet port202and the outlet port214. The dripless quick disconnects302can simplify the process of attaching the cold plate200to a coolant supply/drain. The openings216in the cold plate200can receive connector housings304that are configured to connect an array of electrical components (not illustrated) arranged below the cold plate200to a printed circuit board assembly306. In particular, each of the housings304can house a plurality of pass through connectors (e.g., pogo-pins) that provide for thermal, power, and/or communication connectivity between the electrical components and the printed circuit board assembly306. In certain implementations, the pass through connectors may provide relatively high levels of current such that the pass through connectors generate a significant amount of heat. Thus, the cold plate can also cool the pass through connectors inserted into the openings216in the cold plate200. For example, thermal contact for heat transfer can be created by press fitting the connector housings304into the cold plate200. Also, a thermal interface material can be added between the connector housings304and cold plate200to improve heat transfer. In some examples, the electrical components may comprise VRMs configured to receive power and control signals from the printed circuit board assembly306. The printed circuit board assembly306can include a printed circuit board, such as a control board, and an array of electronic components on the printed circuit board.

In addition, the inlet manifold204and the outlet manifold212can be located in a different plane compared to the body209of the cold plate200as shown inFIGS.4A-4D. By arranging the inlet and outlet manifolds204,212in a different plane, the overall footprint of the cold plate200can be reduced compared to an implementation in which the inlet and outlet manifolds204,212are formed in the same plane as the body209of the cold plate200. Accordingly, aspects of this disclosure can increase the volume efficiency and compactness of the system.

FIGS.5A-5Deach illustrate various heat maps for embodiments for the fins210within one cooling element400of the cold plate200array ofFIG.2. InFIG.5A, the fins210are arranged in parallel with each other.FIG.5Billustrates a serpentine fin210arrangement.FIG.5Cshows an embodiment in which the fins210are cylindrical.FIG.5Dillustrates an embodiment where the fins210are staggered.

Depending on the embodiment, the cold plate200and fins210are designed to increase heat transfer to the coolant218and decrease the flow rate of the coolant218. In some embodiments, the heat transfer to the coolant218may be greater than a threshold heat transfer rate and the flow rate of the coolant may be less than a threshold flow rate. The cold plate200also includes flow paths near the corner of each cooling element400that connect the elements forming the parallel coolant flow paths220(seeFIG.3).

FIGS.6A and6Billustrate an inlet manifold204and the flow of coolant218through the inlet manifold204and flow channels208in accordance with aspects of this disclosure.FIG.6Ashows an enlarged view of the inlet port202, the inlet manifold204, and the flow channels208of the cold plate200.FIG.6Billustrates the flow of coolant218through the inlet port202, the inlet manifold204, and the flow channels208shown inFIG.6A. Each of the flow channels208is connected to the body209of the cold plate200via a corresponding orifice602. In some embodiments, the orifices602have different sizes (e.g., diameters) to control the flow rate of coolant218through each of the orifices602. For example, the pressure of the coolant218may drop for flow paths that are further away from the inlet port202, and thus, the diameters of the orifices602may increase as the distance of the orifices602from the inlet port202increases. In some embodiments, the diameters of the orifices602are selected to provide a substantially equal flow rate through each parallel coolant flow path220. Accordingly, sizes of orifices602can equalize flow rate through parallel coolant flow paths220in the cold plate200.

FIG.7illustrates a cross-sectional view of a portion of the SoW assembly including the cold plate200in accordance with aspects of this disclosure. With reference toFIG.7, the cold plate200is attached to the array of VRMs16. A TIM701is located over each VRM16between the VRM16and the cold plate200. The VRMs16are arranged on the SoW14, which in turn is coupled to a heat dissipation structure702. The cold plate200can be attached to the heat dissipation structure702via a plurality of bolts704extending through the SoW14. The TIM701can reduce the heat transfer resistance between the VRMs16and the cold plate200.

FIG.8is a perspective view of the cold plate200including a plurality of pass through connectors24arranged in the openings in the cold plate200in accordance with aspects of this disclosure. In the illustrated embodiment, the pass through connectors24are implemented as pogo pins which are housed in cartridges. The pogo pins can be used to provide power and/or communication connectivity to connect the VRMs16to the control board20(e.g., as shown inFIG.1).

FIG.9is a plan view illustrating the flow of coolant218through a cold plate900according to an embodiment. In contrast to the embodiment ofFIG.3, the cold plate900is without manifolds. The cold plate900is formed of a plurality of cooling elements cooling elements400, each of which is fluidly connected to all of its adjacent cooling elements400. Thus, rather than forming a plurality of parallel coolant flow paths220, the coolant218can flow both vertically and horizontally to create a substantially diagonal flow through the cold plate900. In some implementations, each of the cooling elements400may enclose a set of pin fins to further facilitate diagonal flow. In one embodiment, the fins may be distributed in a substantially uniform manner to increase performance.

Since the coolant218flows between opposite corners of the cold plate900, the cold plate200can be implemented without manifolds (e.g., see the inlet manifold204and the outlet manifold212ofFIG.2). This reduced the size of the cold plate900and reduces the assembled complexity compared to the manifold design. However, the cold plate200having manifolds may achieve increased cooling compared to the manifold free design900in certain applications.

Any suitable principles and advantages disclosed herein can be applicable to wafer level packaging and/or high density multiple die packaging. Though the embodiments disclosed herein used VRMs as an example, any suitable electrical module, component, die, chip, or the like may be mounted on a wafer and utilize any suitable principles and advantages disclosed herein. Any suitable combination of features of two or more embodiments disclosed herein can be implemented.

The SoW assemblies disclosed herein can be included in a processing system. Features of this disclosure, such as any of the features of the cold plates disclosed herein, can be implemented in any suitable processing system. The processing system can include the SoW assembly10ofFIG.1, for example. The processing system can have a high compute density and can dissipate heat generated by the processing system. The processing system can execute trillions of operations per second in certain applications. The processing system can be used in and/or specifically configured for high performance computing and/or computation intensive applications, such as neural network training and/or processing, machine learning, artificial intelligence, or the like. The processing system can implement redundancy. In some applications, the processing system can be used to perform neural network training to generate data for an autopilot system for vehicle (e.g., an automobile), other autonomous vehicle functionality, or Advanced Driving Assistance System (ADAS) functionality.

In addition, while aspects of this disclosure are described in connection with an array of electronic components, aspects of this disclosure can be applied a cold plate configured to cool a single electronic component on one side. For example, a cold plate configured to cool an electronic component can include one or more openings formed therethrough. The opening(s) can receive one or more pass through connectors configured to provide thermal, power, and/or communication connectivity between the electronic component and a printed circuit board or other electronic component, where the cold plate is arranged between the electronic component and the printed circuit board or other electronic component.

CONCLUSION

The foregoing description has been described with reference to specific embodiments. However, the illustrative discussions above are not intended to be exhaustive or to limit the inventions to the precise forms described. Many modifications and variations are possible in view of the above teachings. Others skilled in the art are thereby enabled to best utilize the techniques and various embodiments with various modifications as suited to various uses.

Although the disclosure and examples have been described with reference to the accompanying drawings, various changes and modifications will become apparent to those skilled in the art. Such changes and modifications are to be understood as being included within the scope of the disclosure.