Shielding cover, circuit board assembly and electronic equipment

Abstract

The invention provides a shielding case, a circuit board assembly and electronic equipment. The shielding case comprises a first packaging piece, a second packaging piece, a supporting piece and a piezoelectric micropump, the supporting piece is arranged in a containing cavity formed by the first packaging piece and the second packaging piece and forms a flow channel, the flow channel is filled with a heat-conducting medium, and the piezoelectric micropump is communicated with the flow channel and used for driving the heat-conducting medium to flow along the flow channel; wherein at least one of the first packaging sheet and the second packaging sheet comprises an electromagnetic shielding material, and the shielding cover is used for covering an electronic component on a circuit board and plays roles in electromagnetic shielding and heat dissipation of the electronic component. According to the shielding case provided by the embodiment of the invention, a liquid-cooled structure is adopted, the heat-conducting medium in the flow channel is driven by the piezoelectric micropump to circularly flow, heat generated when electronic components in the electronic equipment work can be quickly absorbed, the temperature of the electronic components is effectively reduced, and the system is smooth and not blocked while high-performance operation of the electronic equipment is ensured.

Description

Technical Field

[0001] This application relates to the technical field of shielding covers for electronic device circuit boards, and specifically relates to a shielding cover, a circuit board assembly, and an electronic device. Background Art

[0002] With the development of technology, people have more and more functional requirements for smart phones. To meet the increasing functional requirements of mobile phones, the platform and power consumption are upgraded, and the power consumption of the corresponding chips gradually climbs, resulting in an increase in the heat generated by the chips. When the mobile phone runs at a high temperature, there are the following problem points: 1) It will cause the processor to downclock, reducing the running speed and response time of the mobile phone, thus affecting the user experience; 2) Overheating of the mobile phone may cause safety problems, and in the most serious cases, it may cause the battery to expand or even explode; 3) The overheated mobile phone not only feels hot to the touch, but may also cause software failures and system crashes, affecting the user experience; 4) Continuous high temperature will damage the internal hardware components of the mobile phone, such as processors, memory chips, etc., resulting in hardware failures.

[0003] In order to enable electronic devices to be used normally, good heat dissipation performance is particularly important. Currently, the heat dissipation solution for chips in mobile phones is usually as follows: a metal shielding cover is provided above the chip, and the metal shielding cover plays the role of heat dissipation and electromagnetic interference shielding; a thermal interface material is filled between the chip and the shielding cover to reduce the thermal resistance; a copper foil is attached above the shielding cover to further enhance heat dissipation, etc. The material of the metal shielding cover currently used for mobile phone chips is mostly an alloy material of cupronickel, and its thermal conductivity is about 25 W / mK. The thermal conductivity of the copper foil / copper graphite attached above the shielding cover is about 200 - 400 W / mK, and its thermal conductivity is poor, which cannot ensure good temperature uniformity of the shielding cover and cannot effectively dissipate the chip temperature in a timely manner.

[0004] In order to reduce the contact thermal resistance between the mobile phone chip and the outer surface of the shielding cover and improve the temperature uniformity effect of the shielding cover, it is necessary to improve the thermal conductivity of the shielding cover so that the heat conducted from the chip to the shielding cover through the thermal interface material can be quickly and evenly dissipated, quickly reducing the temperature of the mobile phone chip and ensuring the smooth operation of the mobile phone in the high-performance mode. Summary of the Invention

[0005] In the first aspect of the embodiments of this application, a shielding cover is provided. The shielding cover includes a first encapsulation sheet, a second encapsulation sheet, a support member, and a piezoelectric micropump. The support member is disposed in the accommodation cavity formed by the first encapsulation sheet and the second encapsulation sheet and is formed with a flow channel. The flow channel is filled with a heat-conducting medium. The piezoelectric micropump is communicated with the flow channel and is used to drive the heat-conducting medium to flow along the flow channel; wherein, at least one of the first encapsulation sheet and the second encapsulation sheet includes an electromagnetic shielding material. The shielding cover is used to cover the electronic components on the circuit board, playing the role of electromagnetic shielding and heat dissipation for the electronic components.

[0006] In a second aspect, an embodiment of the present application provides a circuit board assembly, which includes a circuit board, electronic components, and the shielding cover described in the above embodiments. The shielding cover covers the electronic components and is fixedly connected to the circuit board.

[0007] In a third aspect, an embodiment of the present application provides an electronic device, which includes a display screen module, a housing, and the circuit board assembly described in the above embodiments. The circuit board assembly is disposed in the housing and is electrically connected to the display screen module.

[0008] The shielding cover provided by the embodiment of the present application adopts a liquid-cooled structure. By driving the circulation of the heat-conducting medium in the flow channel through a piezoelectric micropump, it can quickly absorb the heat generated when the electronic components in the electronic device work, effectively reduce the temperature of the electronic components, and ensure the high-performance operation of the electronic device while the system runs smoothly without jamming. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0010] Figure 1 is a schematic structural diagram of an embodiment of the circuit board assembly of the present application;

[0011] Figure 2 is a schematic cross-sectional structure diagram of an embodiment of the shielding cover of the present application;

[0012] Figure 3 is a schematic exploded structure diagram of the shielding cover in a flattened state;

[0013] Figure 4 is a schematic stacked structure diagram of a packaging sheet composite material of the present application;

[0014] Figure 5 is a schematic structural diagram of another embodiment of the circuit board assembly of the present application;

[0015] Figure 6 is a schematic structural diagram of still another embodiment of the circuit board assembly of the present application;

[0016] Figure 7 is a schematic structural diagram of an embodiment of the electronic device of the present application;

[0017] Figure 8 is Figure 7 a schematic cross-sectional structure diagram of the electronic device at A-A in the embodiment;

[0018] Figure 9 It is a schematic diagram of the structural composition of an embodiment of the electronic device of the present application. Specific Embodiments

[0019] The present application will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be specifically noted that the following embodiments are only used to illustrate the present application, but do not limit the scope of the present application. Similarly, the following embodiments are only some embodiments of the present application rather than all embodiments. All other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of the present application.

[0020] The terms "first", "second", and "third" in the embodiments of the present application are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first", "second", and "third" may explicitly or implicitly include at least one of such features. In the description of the present application, the meaning of "a plurality" is at least two, such as two, three, etc., unless otherwise specifically defined. All directional indications (such as up, down, left, right, front, back...) in the embodiments of the present application are only used to explain the relative positional relationship and movement conditions between components in a specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indications will also change accordingly. The terms "including" and "having" in the embodiments of the present application and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units is not limited to the listed steps or units, but may optionally further include unlisted steps or units, or may optionally further include other steps or components inherent to these processes, methods, products, or devices.

[0021] Referring to "embodiments" herein means that a specific feature, structure, or characteristic described in connection with the embodiments can be included in at least one embodiment of the present application. The phrase appears in various places in the specification and does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. Those skilled in the art will explicitly and implicitly understand that the embodiments described herein can be combined with other embodiments.

[0022] "Electronic device" (or simply "terminal") as used herein includes, but is not limited to, a device configured to receive / transmit communication signals via a wired connection (such as via a Public Switched Telephone Network (PSTN), Digital Subscriber Line (DSL), digital cable, direct cable connection, and / or another data connection / network) and / or via a wireless interface (such as for a cellular network, Wireless Local Area Network (WLAN), digital television network such as a DVB-H network, satellite network, AM-FM broadcast transmitter, and / or another communication terminal). A communication terminal configured to communicate via a wireless interface may be referred to as a "wireless communication terminal", "wireless terminal" or "mobile terminal". Examples of mobile terminals include, but are not limited to, satellite or cellular telephones; Personal Communication System (PCS) terminals that may combine cellular radiotelephone with data processing, facsimile, and data communication capabilities; PDAs that may include a radiotelephone, pager, Internet / intranet access, Web browser, notepad, calendar, and / or Global Positioning System (GPS) receiver; and conventional laptop and / or palmtop receivers or other electronic devices that include a radiotelephone transceiver. A mobile phone is an electronic device configured with a cellular communication module.

[0023] Please refer to Figure 1 , Figure 1 FIG. is a schematic structural diagram of an embodiment of the circuit board assembly of the present application. It should be noted that the circuit board assembly in the present application can be used in an electronic device, and the electronic device can include a mobile phone, a tablet computer, a laptop computer, a wearable device, etc. The circuit board assembly 10 for an electronic device includes, but is not limited to, the following structures: a circuit board 100, electronic components 200, and a shielding cover 300.

[0024] Specifically, the circuit board 100 can be a printed circuit board (PCB). The electronic components 200 are connected to the circuit board 100 by means of surface mounting or soldering. The electronic components 200 can include electronic devices with high heat generation such as chips and those that require electromagnetic shielding. The shielding cover 300 covers the electronic components 200 and is fixedly connected to the circuit board 100. Among them, the fixed connection method between the shielding cover 300 and the circuit board 100 can include mechanical coupling clamping, bonding, soldering, etc. In addition, in some embodiments, the shielding cover 300 can also be designed as a two-piece structure, one piece is soldered to the circuit board 100, and the other piece is connected to it by mechanical coupling. The detailed features of this part are within the understanding of those skilled in the art and will not be elaborated here.

[0025] Optionally, in order to improve the heat conduction efficiency between the electronic components 200 and the shielding cover 300, a thermal interface material 400 can be filled between the electronic components 200 and the shielding cover 300 to reduce the thermal resistance. Among them, the thermal interface material 400 can be a thermal conductive gel, thermal conductive silicone grease, thermal conductive gasket, liquid metal, etc.

[0026] Please refer to Figure 2 and Figure 3 , Figure 2 which is a schematic cross-sectional structure diagram of an embodiment of the shielding cover of the present application, Figure 3 and which is a schematic exploded structure diagram of the shielding cover in a flattened state. The shielding cover 300 in this embodiment includes a first encapsulation sheet 310, a second encapsulation sheet 320, a support member 330, and a piezoelectric micropump 340. Among them, the support member 330 is disposed in the accommodation cavity formed by the first encapsulation sheet 310 and the second encapsulation sheet 320 and is formed with a flow channel 331. A heat-conducting medium (not shown in the figure) is filled in the flow channel 331. The piezoelectric micropump 340 is communicated with the flow channel 331 and is used to drive the heat-conducting medium to flow along the flow channel 331; thereby realizing the transfer of heat. Optionally, the heat-conducting medium can be a liquid medium with good heat-conducting performance such as water or oil. Among them, the piezoelectric micropump 340 can be one or more, not limited to one in the illustrated embodiment, and no specific limitation is made here.

[0027] Optionally, please continue to refer to Figure 2 , in order to ensure the heat dissipation efficiency, the height H of the flow channel 331 of the shielding cover in the embodiment of the present application is 80 - 200 um. This size range of the flow channel 331 can, on the one hand, ensure sufficient size to increase the flow rate of the heat-conducting medium as much as possible, thereby improving the heat dissipation efficiency, and on the other hand, mainly considering from the perspective of the stacking space size of the device, it cannot be too large, which will affect the overall thickness of the circuit board assembly and even the overall thickness of the electronic device.

[0028] Among them, at least one of the first encapsulation sheet 310 and the second encapsulation sheet 320 includes an electromagnetic shielding material, so that when the shielding cover 300 covers the electronic components 200 on the circuit board 100, it can simultaneously play the role of electromagnetic shielding and heat dissipation for the electronic components 200.

[0029] Optionally, at least one of the first encapsulation sheet 310 and the second encapsulation sheet 320 is made of a metal or alloy material, including but not limited to any one of copper and its alloys, aluminum and its alloys, and stainless steel. Among them, one of the first encapsulation sheet 310 and the second encapsulation sheet 320 can be made of a metal or alloy material, while the other can be made of a plastic or resin material.

[0030] In addition, in some embodiments, it can also be that at least one of the first encapsulation sheet 310 and the second encapsulation sheet 320 is made of a composite material. Please refer to Figure 4 , Figure 4It is a schematic diagram of the laminated structure of a packaging sheet composite material in the present application. Among them, the composite material includes a base layer 301 and a film layer 302 arranged in a laminated manner. The material of the base layer 301 is metal or alloy, and the material of the film layer 302 is resin or organic polymer, such as any one or more of PI (Polyimide, abbreviated as PI, polyimide), PET (Polyethyleneterephthalate, abbreviated as PET, polyethylene terephthalate), and PEEK (Polyetheretherketone, abbreviated as PEEK, polyetheretherketone).

[0031] Optionally, the water vapor permeability requirements of the first packaging sheet 310 and the second packaging sheet 320 are less than 1 g / m 2 / 24 hr to ensure the sealing reliability and the reliability of the overall structure (no liquid leakage).

[0032] In the circuit board assembly in the embodiments of the present application, the shielding cover is designed as a liquid-cooled shielding cover. The advantage of such a design is that a heat-conducting medium flow channel is provided inside the liquid-cooled shielding cover, and its theoretical thermal conductivity can reach more than 2000 W / mK, which is much greater than that of cupronickel alloy (about 25 W / mK) and copper (about 400 W / mK). Through the high thermal conductivity of the liquid-cooled shielding cover, the thermal resistance of the shielding cover can be effectively reduced, and the heat absorption capacity for the heat generated by the heating chips (and other electronic components) of the mobile phone can be improved (rapidly increasing the thermal conductivity in the thickness direction and the planar direction of the shielding cover, reducing the heat transfer thermal resistance, improving the heat dissipation effect, and rapidly cooling the temperature of the mobile phone chip), greatly improving the heat dissipation efficiency of the chip, quickly reducing the chip temperature, which helps to further release the performance of the mobile phone while the mobile phone operating system runs smoothly without jamming.

[0033] Please refer to Figure 5 , Figure 5 It is a schematic diagram of the structure of another embodiment of the circuit board assembly in the present application. The circuit board assembly 10 in this embodiment can also include a circuit board 100, electronic components 200, and a shielding cover 300. The circuit board 100 can be a PCB board, and the electronic components 200 can be connected to the circuit board 100 by means of chip mounting or soldering, etc. The electronic components 200 can include electronic devices such as chips that generate a large amount of heat and require electromagnetic shielding. The shielding cover 300 covers the electronic components 200 and is fixedly connected to the circuit board 100. Among them, the fixed connection method between the shielding cover 300 and the circuit board 100 can include mechanical coupling clamping, bonding, soldering, etc.

[0034] A thermal interface material 400 can also be filled between the electronic components 200 and the shielding cover 300 to reduce the thermal resistance. Among them, the thermal interface material 400 can be thermal gel, thermal grease, thermal pad, liquid metal, etc.

[0035] For the detailed structural features of the shielding cover 300 , please refer to the relevant description of the aforementioned embodiment, which will not be repeated here.

[0036] Different from the aforementioned embodiment, the circuit board assembly 10 in this embodiment further includes a heat conducting plate 500, which is bonded to the shielding cover 300 and may be bonded to the outer surface of the shielding cover 300. The heat conducting plate 500 may be made of graphite, copper foil, etc., which may further improve the heat dissipation efficiency of the circuit board assembly 10.

[0037] See also Figure 6 , Figure 6 It is a structural schematic diagram of another embodiment of the circuit board assembly of the present application. The circuit board assembly 10 in this embodiment includes a circuit board 100, an electronic component 200, a shielding cover 300, a heat conducting plate 500 and a heat spreader 600, wherein the electronic component 200 is connected to the circuit board 100, the shielding cover 300 is covered on the electronic component 200 and is fixedly connected to the circuit board 100, a thermal interface material 400 is filled between the electronic component 200 and the shielding cover 300, the heat conducting plate 500 is arranged to be bonded to the shielding cover 300, and can be bonded to the outer surface of the shielding cover 300, the heat spreader 600 can be bonded to the side of the heat conducting plate 500 that is away from the shielding cover 300, and the other side of the heat spreader 600 can be bonded to the middle frame of the electronic device to further improve the heat dissipation efficiency. The detailed structure of the heat spreader 600 (with a capillary structure and a heat conducting medium inside) is within the scope of understanding of those skilled in the art and will not be repeated here.

[0038] Furthermore, the present application also provides an electronic device. The electronic device in this embodiment may include a mobile phone, a tablet computer, a laptop computer, a wearable device, etc. The mobile phone is used as an example for description. Figure 7 and Figure 8 , Figure 7 is a structural diagram of an embodiment of the electronic device of the present application, Figure 8 yes Figure 7 The electronic device in the embodiment is a schematic cross-sectional view of the structure at AA. The electronic device in the embodiment may include a circuit board assembly 10, a display module 20 and a housing 30, wherein the housing 30 in the embodiment may include a middle frame 31 and a back cover 32. The circuit board assembly 10 may be the structure in the aforementioned embodiment, which will not be described in detail here.

[0039] Optionally, the display screen module 20 and the back cover 32 are respectively matched with the middle frame 31 to form an accommodating space 1000, and the circuit board assembly 10 is disposed in the accommodating space 1000. The circuit board assembly 10 is electrically connected to the display screen module 20, and the circuit board assembly 10 is used to control the display screen module 20. The detailed technical features of the other parts of the electronic device are within the scope of understanding of those skilled in the art and will not be repeated here.

[0040] Please refer to Figure 9 , Figure 9 which is a schematic block diagram of the structural composition of an embodiment of the electronic device of the present application. The electronic device can be a mobile phone, a tablet computer, a laptop computer, a wearable device, etc. In this embodiment, the mobile phone is taken as an example. The structure of the electronic device may include an RF circuit 910, a memory 920, an input unit 930, a display unit 940 (which can be the display screen module 20 in the above embodiment), a sensor 950, an audio circuit 960, a wifi module 970, a processor 980 (which can be the circuit board assembly 10 in the foregoing embodiment), and a power supply 990, etc. Among them, the RF circuit 910, the memory 920, the input unit 930, the display unit 940, the sensor 950, the audio circuit 960, and the wifi module 970 are respectively connected to the processor 980; the power supply 990 is used to provide electrical energy for the entire electronic device.

[0041] Specifically, the RF circuit 910 is used to receive and send signals; the memory 920 is used to store data instruction information; the input unit 930 is used to input information, which may specifically include a touch panel 931 and other input devices 932 such as operation buttons; the display unit 940 may include a display panel 941, etc.; the sensor 950 includes an infrared sensor, a laser sensor, etc., and is used to detect user proximity signals, distance signals, etc.; the speaker 961 and the microphone (or microphone) 962 are connected to the processor 980 through the audio circuit 960 and are used to receive and send sound signals; the wifi module 970 is used to receive and transmit wifi signals, and the processor 980 is used to process the data information of the electronic device. For the specific structural features of the electronic device, please refer to the relevant descriptions of the above embodiments, and no detailed introduction will be given here.

[0042] In the electronic device of this embodiment, the shielding cover of the circuit board assembly adopts a liquid-cooled structure. By driving the circulating flow of the heat-conducting medium in the flow channel through a piezoelectric micropump, the heat generated by the electronic components during operation in the electronic device can be quickly absorbed, effectively reducing the temperature of the electronic components, and ensuring the high-performance operation of the electronic device while the system runs smoothly without jamming.

[0043] The above are only some embodiments of the present application, and thus do not limit the protection scope of the present application. Any equivalent device or equivalent process transformation made by using the content of the specification and drawings of the present application, or directly or indirectly applied in other related technical fields, shall be equally included in the patent protection scope of the present application.

Claims

1. A shielding cover, characterized in that: The shielding cover includes a first packaging sheet, a second packaging sheet, a support member and a piezoelectric micropump. The support member is arranged in a accommodating cavity formed by the first packaging sheet and the second packaging sheet and forms a flow channel. The flow channel is filled with a heat-conducting medium. The piezoelectric micropump is connected to the flow channel and is used to drive the heat-conducting medium to flow along the flow channel. At least one of the first packaging sheet and the second packaging sheet includes an electromagnetic shielding material. The shielding cover is used to cover electronic components on a circuit board to play an electromagnetic shielding and heat dissipation role for the electronic components.

2. The shielding cover according to claim 1, characterized in that: The height of the flow channel is 80-200um.

3. The shielding cover according to claim 1, characterized in that: The water vapor permeability of the first encapsulation sheet and the second encapsulation sheet is less than 1g / m 2 / 24hr.

4. The shielding cover according to claim 1, characterized in that: At least one of the first packaging sheet and the second packaging sheet is made of metal or alloy material.

5. The shielding cover according to claim 4, characterized in that: A material of at least one of the first encapsulation sheet and the second encapsulation sheet is any one of copper and its alloy, aluminum and its alloy, and stainless steel.

6. The shielding cover according to claim 1, characterized in that: At least one of the first encapsulation sheet and the second encapsulation sheet is made of a composite material, wherein the composite material includes a base layer and a film layer that are stacked, the base layer is made of metal or alloy, and the film layer is made of resin or organic polymer.

7. The shielding cover according to claim 6, characterized in that: The material of the film layer includes any one or more of PI, PET, and PEEK.

8. A circuit board assembly, characterized in that: The circuit board assembly comprises a circuit board, electronic components and the shielding cover according to any one of claims 1 to 7, wherein the shielding cover is disposed on the electronic components and is fixedly connected to the circuit board.

9. The circuit board assembly according to claim 8, characterized in that: The circuit board assembly further comprises a heat conducting plate, and the heat conducting plate is arranged in close contact with the shielding cover.

10. An electronic device, characterized in that: The electronic device comprises a display screen module, a housing and the circuit board assembly according to claim 8 or 9, wherein the circuit board assembly is arranged in the housing and is electrically connected to the display screen module.

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