CN112996232A

CN112996232A - PCB substrate and high-frequency high-speed PCB for 5G base station

Info

Publication number: CN112996232A
Application number: CN202110219724.5A
Authority: CN
Inventors: 杨兴德
Original assignee: Ganzhou Xin Lian Xing Technology Co ltd
Current assignee: Ganzhou Xin Lian Xing Technology Co ltd
Priority date: 2021-02-26
Filing date: 2021-02-26
Publication date: 2021-06-18
Anticipated expiration: 2041-02-26
Also published as: CN112996232B

Abstract

The invention discloses a PCB substrate which comprises a plurality of silicon chips, a reinforcing layer, a filling layer and a copper sheet layer, wherein the copper sheet layer comprises a heat dissipation layer and an electrical element mounting layer; the reinforcing layer is arranged between the copper sheet layers and is used for improving the toughness of the PCB substrate; the filling layer is arranged between the copper sheet layers and wraps the outside of the filling layer; the silicon chip is arranged between the heat dissipation layer and the electric appliance element mounting layer and used for guiding and dissipating heat on the electric appliance element mounting layer to the heat dissipation layer without the electronic element. In summary, the PCB substrate disclosed in the present invention has the advantage of good heat dissipation performance.

Description

PCB substrate and high-frequency high-speed PCB for 5G base station

Technical Field

The invention relates to the field of PCBs, in particular to a PCB substrate and a high-frequency and high-speed PCB for a 5G base station.

Background

With the continuous development of communication technology, the fifth generation mobile communication technology (5G) already covers most of cities, while the 5G technology requires high data rate, delay reduction, energy saving, cost reduction, system capacity improvement and large-scale equipment connection, and also requires high frequency and high speed requirements on a PCB board used in a 5G base station, in the prior art, a multilayer structure stacked structure is usually adopted to improve the performance of the PCB board, but the multilayer structure PCB board has poor heat dissipation capability, so that the PCB board generates heat seriously after working for a long time, and even the PCB board is burnt out to influence the normal work of the 5G base station.

Disclosure of Invention

The invention aims to provide a PCB (printed circuit board) substrate, which is used for solving the technical problem that a PCB in the prior art is poor in heat dissipation performance.

In order to achieve the above object, the present invention adopts a technical solution of providing a PCB substrate, comprising:

the copper sheet layer comprises a heat dissipation layer and an electrical element mounting layer;

the reinforcing layer is arranged between the copper sheet layers and is used for improving the toughness of the PCB substrate;

the filling layer is arranged between the copper sheet layers and wraps the outside of the filling layer;

the silicon wafers are arranged between the heat dissipation layer and the electric appliance element mounting layer and used for guiding and dissipating heat on the electric appliance element mounting layer to the heat dissipation layer without the electronic element.

In one embodiment, the semiconductor device further comprises a thermal via penetrating the copper sheet layer and the filling layer.

In one embodiment, the reinforcing layer is made of a fiberglass material and the filler layer is made of a resin mixture.

Another object of the present invention is to provide a high-frequency and high-speed PCB board for a 5G base station, which includes the PCB substrate according to any of the above embodiments, and further includes a liquid-gas circulation heat dissipation device, the liquid-gas circulation heat dissipation device is in close contact with and fits with the heat dissipation layer, and the liquid-gas circulation heat dissipation device includes:

the heat dissipation layer is arranged on the copper sheet layer, the gasification heat absorption part is in close contact fit with the heat dissipation layer in the copper sheet layer, liquid circulating cooling matters flow inside the gasification heat absorption part, and the gasification heat absorption part absorbs heat on the heat dissipation layer in a way of gasifying and absorbing heat through the liquid circulating cooling matters, so that the heat dissipation effect of the PCB substrate is improved;

the condensation liquefaction part is communicated with the gasification heat absorption part through a pipeline and is used for recondensing the gasified circulating cooling object into liquid and inputting the liquid into the gasification heat absorption part for recycling;

the external cooling device is arranged at the periphery of the condensation liquefaction part and used for absorbing heat on the condensation liquefaction part, and therefore gas in the condensation liquefaction part is liquefied into liquid rapidly.

In one embodiment, the liquid-gas circulation heat dissipation device further includes a pressure protection device, the pressure protection device is disposed in the condensation liquefaction portion, and the pressure protection device is configured to control the pressure inside the liquid-gas circulation heat dissipation device, so as to prevent the liquid-gas circulation heat dissipation device from being damaged due to excessive internal pressure.

In one embodiment, the pressure protection device comprises:

a pressure relief piston slidably fitted inside one end of the condensation-liquefaction section;

one end of the pressure relief elastic piece is connected with the condensation liquefaction part, the other end of the pressure relief elastic piece is connected with the pressure relief piston, and when the air pressure in the condensation liquefaction part is overlarge, the pressure relief piston slides under the action of the air pressure and overcomes the elasticity of the pressure relief elastic piece;

the pressure relief hole is arranged at one end of the condensation liquefaction part, when the internal pressure of the condensation liquefaction part is overlarge, the pressure relief piston slides to the end part of the condensation liquefaction part, the pressure relief hole is communicated with the inner cavity of the condensation liquefaction part, and the pressure relief hole performs pressure relief treatment on the condensation liquefaction part;

and the pressure relief recovery pipe is arranged on the pressure relief hole and used for recovering the externally discharged circulating cooling gas when the pressure protection device performs pressure relief.

In one embodiment, the inner cavity of the condensation liquefaction part is obliquely arranged, so that the circulating cooling object condensed and liquefied in the condensation liquefaction part is collected under the self gravity and enters the gasification heat absorption part through a pipeline.

In one embodiment, the high-frequency and high-speed PCB board for the 5G base station comprises a plurality of PCB base materials, the PCB base materials are stacked with one another, each PCB base material corresponds to one of the gasification heat absorption portions, and a plurality of heat conduction columns are arranged between the gasification heat absorption portions.

In one embodiment, the external cooling device is internally circulated with cooling water, and the cooling water wraps the condensation liquefaction part.

In one embodiment, the high-frequency high-speed PCB board for a 5G base station further includes an external cooling power adjusting device for adjusting an output power of the external cooling device, the external cooling power adjusting device including:

one end of the resistance rod is fixedly connected with one side of the pressure relief piston close to the end part of the condensation liquefaction part, and the other end of the resistance rod penetrates through the end face of the condensation liquefaction part and is electrically connected with one end of a power supply of the external cooling device through a lead;

the electric brush is fixed on the end face of the condensation liquefaction part, is in sliding fit with the resistor rod, and one end of the electric brush is connected with the other end of the power supply of the external cooling device through a lead.

One or more technical solutions described above in the embodiments of the present invention have at least the following technical effects or advantages:

the PCB substrate provided by the embodiment of the invention comprises a plurality of silicon chips, a reinforcing layer, a filling layer and a copper sheet layer, wherein the copper sheet layer comprises a heat dissipation layer and an electrical element mounting layer; the reinforcing layer is arranged between the copper sheet layers and is used for improving the toughness of the PCB substrate; the filling layer is arranged between the copper sheet layers and wraps the outside of the filling layer; the silicon chip is arranged between the heat dissipation layer and the electric appliance element mounting layer and used for guiding and dissipating heat on the electric appliance element mounting layer to the heat dissipation layer without the electronic element. Through set up the silicon chip between the copper sheet layer for on the electrical components installation layer by electrical components work the heat that produces can pass through the silicon chip fast transmission to the heat dissipation layer, give off the heat through the heat dissipation layer fast, avoid electrical components installation layer to gather the heat, improve the heat dispersion of PCB board. In addition, the embodiment of the invention also adopts a liquid-gas circulation heat dissipation device and the PCB substrate to combine the high-frequency high-speed PCB for the 5G base station, adopts the process of gasifying and absorbing heat of easily gasified circulation cooling matters (such as isopentane and the like) to absorb heat on the heat dissipation layer, recovers and condenses the gasified circulation cooling matters into liquid through the condensation liquefaction part, and conveys the liquid circulation cooling matters into the gasification heat absorption part again through a pipeline, thereby realizing the continuous cooling of the heat dissipation layer of the PCB substrate and further improving the heat dissipation performance of the PCB.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed for the embodiments or the prior art descriptions will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.

Fig. 1 is a schematic structural diagram of a PCB substrate according to an embodiment of the present invention;

fig. 2 is a schematic structural diagram of a high-frequency and high-speed PCB board for a 5G base station according to an embodiment of the present invention;

FIG. 3 is a schematic structural view of a high-frequency high-speed PCB for a 5G base station in a pressure relief state;

FIG. 4 is an enlarged view of a portion of FIG. 2 at A;

FIG. 5 is a schematic structural view of an external cooling power adjusting apparatus;

fig. 6 is a circuit diagram of an external cooling power adjusting apparatus.

Wherein, in the figures, the respective reference numerals:

1. a PCB substrate; 2. a liquid-gas circulation heat dissipation device; 11. a copper sheet layer; 12. a reinforcing layer; 13. a filling layer; 14. a silicon wafer; 15. heat dissipation holes; 21. a gasification heat absorption part; 22. a condensation liquefaction part; 23. an external cooling device; 24. a pressure protection device; 25. a heat-conducting column; 26. an external cooling power adjusting device; 241. a pressure relief piston; 242. a pressure relief elastic member; 243. a pressure relief hole; 244. a pressure relief recovery pipe; 261. a resistance rod; 262. an electric brush; 263. a button; 264. a fan.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are illustrative and intended to be illustrative of the invention and are not to be construed as limiting the invention.

In the description of the present invention, it is to be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like, indicate orientations or positional relationships based on the orientations or positional relationships illustrated in the drawings, and are used merely for convenience in describing the present invention and for simplicity in description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed in a particular orientation, and be operated, and thus, are not to be construed as limiting the present invention.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise.

In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

Referring to fig. 1, an embodiment of the present application provides a PCB substrate, which includes a copper sheet layer, a reinforcement layer, a filling layer, and a plurality of silicon chips, wherein the copper sheet layer includes a heat dissipation layer (a layer without electronic components) and an electrical component mounting layer. The enhancement layer sets up between the copper sheet layer, and the enhancement layer is used for improving the toughness of PCB substrate, and the enhancement layer adopts to have mechanical strength high material to make for PCB board intensity improves. The filling layer is arranged between the copper sheet layers and wrapped outside the filling layer, and the filling layer is filled between the copper sheet layers and used for supporting the copper sheet layers. The silicon chip is arranged between the heat dissipation layer and the electric appliance element mounting layer and used for guiding and dissipating heat on the electric appliance element mounting layer to the heat dissipation layer without the electronic element. The silicon chip has good heat-conducting property and certain insulativity, so that when the PCB works and electronic components on the electric appliance component mounting layer work and generate heat, heat on the electric appliance component mounting layer can be quickly transferred to the heat dissipation layer through the silicon chip, and the PCB is prevented from being damaged due to poor heat dissipation performance of the electric appliance component mounting layer. And the two ends of the silicon chip are respectively clung to the heat dissipation layer and the electric appliance element mounting layer, so that the heat transfer effect of the silicon chip can be improved (the silicon chip is directly contacted with the copper sheet layer, and no other substance is arranged in the middle to obstruct heat transfer, so that the heat on the electric appliance element mounting layer can be quickly transferred to the heat dissipation layer). Therefore, the PCB substrate disclosed by the embodiment has good heat dissipation performance.

Referring to fig. 1, in an embodiment, the PCB substrate 1 further includes heat dissipation holes 15, the heat dissipation holes 15 are disposed through the copper sheet layer 11 and the filling layer 13, and the through heat dissipation holes 15 can enable external air flow to take away heat originally located on the electrical component mounting layer through the heat dissipation holes 15 (take away heat on the electrical component mounting layer through a convection heat transfer method), so as to reduce heat on the electrical component mounting layer, and further improve heat dissipation performance of the PCB substrate 1.

In one embodiment, the reinforcing layer 12 is made of a fiberglass material and the filler layer 13 is made of a resin mixture. The glass fiber material has good toughness, good insulating property, strong heat resistance, good corrosion resistance and high mechanical strength, and further, when the glass fiber material is added into the PCB substrate 1, the strength of the PCB substrate 1 is enhanced.

Referring to fig. 2 to 4, an embodiment of the present invention further provides a high-frequency and high-speed PCB board for a 5G base station, including the PCB substrate 1 according to any one of the above embodiments, the high-frequency and high-speed PCB board for a 5G base station further includes a liquid-gas circulation heat dissipation device 2, the liquid-gas circulation heat dissipation device 2 is in close contact with a heat dissipation layer, and the liquid-gas circulation heat dissipation device 2 includes a gasification heat absorption portion 21, a condensation liquefaction portion 22, and an external cooling device 23. The gasification heat absorption part 21 is in close contact with and is matched with the heat dissipation layer in the copper sheet layer 11, liquid circulating cooling materials (liquid materials which are easy to gasify at normal temperature) circulate inside the gasification heat absorption part 21, and the gasification heat absorption part 21 absorbs heat on the heat dissipation layer in a way of gasifying and absorbing heat through the liquid circulating cooling materials (when liquid is converted into gas, the entropy value of the materials is increased, so that heat needs to be absorbed to the outside), so that the heat dissipation effect of the PCB substrate 1 is improved. The condensation liquefaction part 22 is communicated with the gasification heat absorption part 21 through a pipeline, and the condensation liquefaction part 22 is used for condensing the gasified circulating cooling object into liquid again and inputting the liquid into the gasification heat absorption part 21 for recycling. After the recirculated cooling thing absorbed heat and gasified into the gaseous state, circulate to condensation liquefaction portion 22 in through the pipeline, and condensation liquefaction portion 22 inside temperature is lower (adopt modes such as cooling water to cool off condensation liquefaction portion 22, and then control condensation liquefaction portion 22 and be in lower temperature), when gaseous recirculated cooling thing enters into condensation liquefaction portion 22, under condensation liquefaction portion 22's effect, gaseous recirculated cooling thing emits the heat and liquefies into liquid, then liquid recirculated cooling thing rethread pipeline flows into gasification heat absorption portion 21 and carries out next gasification heat absorption, the circulation is reciprocal, realize the purpose that improves PCB board heat dissipation cooling effect. The external cooling device 23 is disposed at the periphery of the condensation and liquefaction part 22, and the external cooling device 23 is used for absorbing heat on the condensation and liquefaction part 22, so as to facilitate rapid liquefaction of the gas in the condensation and liquefaction part 22 into liquid. The external cooling device 23 may employ a cooling pipe through which cooling water flows to cool the condensation/liquefaction unit 22, thereby ensuring the condensation/liquefaction function of the condensation/liquefaction unit 22. Compare and directly let in 1 surface of PCB substrate with recirculated cooling water and cool off PCB, adopt this application the scheme better cooling radiating effect has to adopt the not conducting liquid can avoid the PCB board to take place the short circuit as recirculated cooling thing (such as isopentane etc.), and then can also ensure the stable work of PCB board when improving PCB board heat dispersion.

Referring to fig. 2 or fig. 3, in an embodiment, the liquid-gas circulation heat dissipation device 2 further includes a pressure protection device 24, the pressure protection device 24 is disposed in the condensation liquefaction portion 22, and the pressure protection device 24 is used for controlling the pressure inside the liquid-gas circulation heat dissipation device 2, so as to prevent the liquid-gas circulation heat dissipation device 2 from being damaged due to an excessive internal pressure. The pressure protection device 24 is a structure communicated and sealed with the circulating heat dissipation device, and when the air pressure inside the circulating heat dissipation device is increased, the pressure protection device 24 can automatically change to enlarge the space inside the circulating heat dissipation device, so that the air pressure value inside the circulating heat dissipation device is reduced. Further, the pressure protection device 24 may be an air bag communicated with the condensation liquefaction part 22, and the air bag can be expanded or contracted freely, so that when the air pressure inside the circulation heat dissipation device becomes large, the air bag expands to increase the air storage space, thereby reducing the air pressure value inside the circulation heat dissipation device and ensuring that the circulation heat dissipation device is not damaged due to excessive pressure.

In one embodiment, the pressure protection device 24 includes a pressure relief piston 241, a pressure relief resilient member 242, a pressure relief aperture 243, and a pressure relief recovery tube 244. The pressure relief piston 241 is slidably fitted into the interior of one end of the condensation-liquefaction part 22, and divides the condensation-liquefaction part 22 into two sections, one being a space in which the circulating coolant is circulated and the other being a space in which the pressure relief piston 241 is retractable. One end of the pressure relief elastic member 242 (spring or elastic sheet) is connected to the condensation liquefaction part 22, the other end of the pressure relief elastic member 242 is connected to the pressure relief piston 241, the pressure relief elastic member 242 is located in a retractable space of the piston, and when the air pressure inside the condensation liquefaction part 22 is too high, the pressure relief piston 241 slides against the elastic force of the pressure relief elastic member 242 under the action of the air pressure. The pressure relief hole 243 is provided at one end of the condensation/liquefaction unit 22, and when the internal pressure of the condensation/liquefaction unit 22 is excessively high, the pressure relief piston 241 slides to the end of the condensation/liquefaction unit 22, and the pressure relief hole 243 communicates with the inner cavity of the condensation/liquefaction unit 22, so that the pressure relief hole 243 relieves the pressure of the condensation/liquefaction unit 22. The pressure relief recovery pipe 244 is disposed on the pressure relief hole 243, and the pressure relief recovery pipe 244 is used for recovering the circulating cooling gas discharged when the pressure protection device 24 performs pressure relief. Through the arrangement of the pressure relief hole 243, when the pressure inside the circulating heat dissipation device is increased due to the fact that the circulating cooling object is basically in a gaseous state due to the fact that the circulating heat dissipation device is in a failure state (the condensation liquefaction part 22 does not work or the working efficiency is too low), the pressure relief processing can be performed by controlling the pressure inside the circulating heat dissipation device to be in a preset critical value pressure through the pressure relief hole 243, the circulating heat dissipation device is further prevented from being damaged due to the fact that the internal pressure is too large, the critical value pressure of pressure relief can be accurately set by controlling the elastic force of the elastic part when the pressure relief piston 241 slides to a pressure relief position, and the safe operation of the circulating heat dissipation device.

In one embodiment, the inner cavity of the condensation liquefaction part 22 is obliquely arranged, and the inclination angle is controlled to be between 2 ° and 5 °, so that the circulating cooling object condensed and liquefied in the condensation liquefaction part 22 is collected under the self gravity and enters the gasification heat absorption part 21 through a pipeline, and the circulating cooling object is ensured to be automatically collected through the pipeline and enter the gasification heat absorption part 21 under the action of the self gravity, thereby improving the circulating heat dissipation capability of the circulating heat dissipation device.

In one embodiment, the high-frequency and high-speed PCB board for the 5G base station comprises a plurality of PCB substrates 1, the PCB substrates 1 are stacked on one another, each PCB substrate 1 corresponds to one gasification heat absorption part 21, and a plurality of heat conduction columns 25 are arranged between the gasification heat absorption parts 21. Adopt the function that the PCB structure of heap can improve the PCB board, through interconnect between heat conduction post 25 with each gasification heat absorption portion 21 during expert for when a certain gasification heat absorption portion 21 breaks down and leads to its heat-absorbing capacity to reduce, can give off its own heat transfer to adjacent gasification heat absorption portion 21 through heat conduction post 25 on, and then make the circulation heat abstractor can certainly cool down to PCB inboard.

In one embodiment, the cooling water flows through the external cooling device 23, and the cooling water wraps the condensation and liquefaction part 22. The external cooling device 23 may cool the condensation-liquefaction part 22 by circulating cooling water inside. Compare in hugging closely condensation liquefaction portion 22 surface setting with external cooling device 23 surface, locate condensation liquefaction portion 22 surface with external cooling device 23 cover for the surface of cooling water direct contact condensation liquefaction portion 22 can improve the cooling effect of cooling water to condensation liquefaction portion 22 (avoid the thermal-insulated effect of external cooling device 23 outer wall), and then makes external cooling device 23 better to the cooling effect of external cooling device 23.

Referring to fig. 4, in an embodiment, a plurality of protrusions protruding outward are disposed on the surface of the gasification heat absorption portion 21, and the protrusions are matched with the grooves on the surface of the copper sheet layer 11. Through the cooperation structure that sets up lug and recess for the area of contact on gasification heat absorption portion 21 and copper sheet layer 11 surface enlarges, and then makes the heat on the copper sheet layer 11 can be faster transmit to gasification heat absorption portion 21 on (during the contact heat transfer, the area of contact of the two is big more, heat transfer speed is fast more), and then improves circulation heat abstractor's radiating effect, makes the heat-sinking capability of PCB board better.

Referring to fig. 5, in an embodiment, the high-frequency and high-speed PCB for the 5G base station further includes an external cooling power adjusting device 26 for adjusting the output power of the external cooling device 23, the external cooling power adjusting device 26 includes a resistor bar 261 and a brush 262, one end of the resistor bar 261 is fixedly connected to one side of the pressure relief piston 241 near the end of the condensation liquefaction part 22, and the other end of the resistor bar 261 penetrates through the end face of the condensation liquefaction part 22 and is electrically connected to one end of the power supply of the external cooling device 23 through a conducting wire. The brush 262 is fixed on the end face of the condensation liquefaction part 22, the brush 262 is in sliding fit with the resistance rod 261, and one end of the brush 262 is connected to the power supply of the external cooling device 23 through a lead and the other end is electrically connected. When the internal pressure of the condensation and liquefaction part 22 rises, the pressure relief piston 241 moves towards the pressure relief hole 243, so that the resistance rod 261 moves along with the pressure relief piston, the distance between the brush 262 and the end of the resistance rod 261 connected with the lead wire is lengthened, the resistance value between the brush 262 and the lead wire connected with the end of the resistance rod 261 is further increased, because the resistance rod 261 and the power output part (adopting a pump body structure and the like) of the external cooling device 23 are connected in parallel, when the resistance value connected in parallel is increased, the current flowing in the power output part in the external cooling device 23 is increased (as shown in a circuit diagram shown in fig. 6), the output power is increased, and the cooling effect in the external cooling device 23 is further improved, for example, when the external cooling device 23 cools the condensation and liquefaction part 22 by circulating cooling water, and when the water pump output power of the external cooling device 23 is increased, the faster the cooling water flows through the external cooling device 23, the higher the cooling effect of the external cooling device 23, and the higher the condensation effect of the condensation/liquefaction unit 22.

Referring to fig. 5, in an embodiment, a button 263 may be further disposed at an inner end of the condensation liquefaction portion 22, the button 263 controls the fan 264 disposed beside the PCB substrate 1, when the pressure relief piston 241 moves due to a large internal pressure of the condensation liquefaction portion 22, the button 263 is triggered, so that the fan 264 operates, and the fan 264 is additionally added to assist in dissipating heat from the PCB, thereby further ensuring heat dissipation effect and stability of the PCB.

The present invention is not limited to the above preferred embodiments, and any modifications, equivalent substitutions and improvements made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A PCB substrate, comprising;

2. The PCB substrate of claim 1, wherein:

still include the louvre, the louvre link up set up in the copper sheet layer and the filling layer.

3. The PCB substrate of claim 1, wherein:

the reinforcing layer is made of glass fiber materials, and the filling layer is made of resin mixture.

4. A high-frequency high-speed PCB board for a 5G base station, which comprises the PCB substrate of any one of claims 1 to 3, and is characterized in that the high-frequency high-speed PCB board for the 5G base station further comprises a liquid-gas circulation heat dissipation device, the liquid-gas circulation heat dissipation device is in close contact fit with the heat dissipation layer, and the liquid-gas circulation heat dissipation device comprises:

5. The high-frequency high-speed PCB board for the 5G base station according to claim 4, wherein:

the liquid-gas circulation heat dissipation device further comprises a pressure protection device, the pressure protection device is arranged in the condensation liquefaction part and used for controlling the air pressure inside the liquid-gas circulation heat dissipation device, and the liquid-gas circulation heat dissipation device is prevented from being damaged due to overlarge internal pressure.

6. The high-frequency high-speed PCB board for the 5G base station as claimed in claim 5, wherein the pressure protection device comprises:

7. The high-frequency high-speed PCB board for the 5G base station according to claim 4, wherein:

the inner cavity of the condensation liquefaction part is obliquely arranged, so that circulating cooling matters after condensation liquefaction in the condensation liquefaction part are collected under the self gravity and enter the gasification heat absorption part through a pipeline.

8. The high-frequency high-speed PCB board for the 5G base station according to claim 4, wherein:

the high-frequency and high-speed PCB for the 5G base station comprises a plurality of PCB base materials, the PCB base materials are mutually stacked, each PCB base material corresponds to one gasification heat absorption part, and a plurality of heat conduction columns are arranged between the gasification heat absorption parts.

9. The high-frequency high-speed PCB board for the 5G base station according to claim 4, wherein:

and cooling water flows through the external cooling device, and the cooling water wraps the condensation liquefaction part.

10. The high-frequency high-speed PCB board for the 5G base station as claimed in claim 6, wherein the high-frequency high-speed PCB board for the 5G base station further comprises an external cooling power adjusting device for adjusting the output power of the external cooling device, the external cooling power adjusting device comprises: