Printed circuit board layout determination method, printed circuit board and server

Abstract

The present application discloses a method for determining the layout of a printed circuit board, including: obtaining first stacking information of the printed circuit board; calculating the impedance of the surface routing based on the first stacking information under different environments; adjusting the parameters of the routing and increasing the thickness of the solder resist layer when the impedance difference is greater than a preset threshold, and re-executing the calculation of the impedance of the surface routing based on the first stacking information under different environments until the impedance difference under the different environments is less than or equal to the preset threshold or reaches a preset stop condition. The parameters of the routing and the thickness of the solder resist layer are adjusted according to the impedance difference of the surface routing under different environments, thereby reducing the influence of different operating environments on the printed circuit board signal, and obtaining a printed circuit board that can be used in different operating environments.

Description

Technical Field

[0001] The present application belongs to the field of electronic technology, and specifically relates to a printed circuit board layout determination method, a printed circuit board and a server. Background Art

[0002] As server performance improves, server power consumption also continues to rise. Traditional air cooling is not enough to meet the heat dissipation needs. Liquid cooling is one of the current technical directions for solving the heat dissipation of high-heat server equipment. Liquid cooling refers to the use of liquid refrigerant to directly remove the heat from the equipment to solve the heat dissipation problem. Liquid cooling methods are currently divided into two categories: cold plate type and immersion type. Immersion liquid cooling is to immerse the entire server motherboard in the refrigerant for heat dissipation.

[0003] With the popularization of liquid cooling technology, the issues involved in the design of printed circuit boards under liquid cooling conditions have received more and more attention. Due to the change in heat dissipation methods, the working environment of printed circuit boards has also changed. The working environment of printed circuit boards has a great impact on the signal integrity of printed circuit boards, especially the signal integrity of surface traces.

[0004] During the research process, the inventors found that in the related art, the impact of changes in heat dissipation methods on the integrity of printed circuit board signals was not fully considered during the design process of the printed circuit board. As a result, in certain specific circumstances, such as when the overall margin of the printed circuit board is relatively small, it is feasible for the printed circuit board to operate under air cooling conditions, but when the printed circuit board is operated under liquid cooling conditions, there may be a risk that the signal receiving end cannot correctly identify the signal due to large signal distortion. Summary of the invention

[0005] The purpose of the present application is to provide a printed circuit board layout determination method, a printed circuit board and a server to solve the problem of large signal distortion of the printed circuit board under different operating environment conditions.

[0006] In order to solve the above technical problems, the present application provides a method for determining a printed circuit board layout, comprising:

[0007] Acquire first stacking information of the printed circuit board; the first stacking information includes a solder resist layer covering the surface layer;

[0008] Under a first environment, a first impedance of a surface wiring is calculated based on the first stacking information, and under a second environment, a second impedance of the surface wiring is calculated based on the first stacking information;

[0009] When the difference between the first impedance and the second impedance is greater than a preset threshold, the parameters of the routing are adjusted and the thickness of the solder resist layer is increased, and the steps of calculating the first impedance of the routing of the surface layer based on the first stacking information under the first environment and calculating the second impedance of the routing of the surface layer based on the first stacking information under the second environment are re-executed until the difference between the first impedance and the second impedance is less than or equal to the preset threshold or a preset stop condition is reached.

[0010] Optionally, the first environment is an air environment, and the second environment is a liquid environment.

[0011] Optionally, the adjusting the parameters of the routing includes:

[0012] Adjust the line width and / or line spacing of the routing, wherein the line width is the width value of the surface line, and the line spacing is the differential pair line spacing.

[0013] Optionally, before adjusting the parameters of the routing and increasing the thickness of the solder resist layer, the method further includes:

[0014] In the case where the difference between the first impedance and the second impedance is greater than a preset threshold, displaying a solder resist layer thickness setting control, wherein the solder resist layer thickness setting control is bound to the first stacking information and is used to adjust the thickness of the solder resist layer;

[0015] When a first input to the solder resist layer thickness setting control is received, the input second solder resist layer is superimposed on the first solder resist.

[0016] Optionally, before obtaining the first stacking information of the printed circuit board, the method further includes:

[0017] receiving stack-up configuration information of a printed circuit board;

[0018] Based on the stacking configuration information of the printed circuit board, the routing of the surface layer of the printed circuit board is modeled; wherein, during the modeling, the line width and line spacing of the routing of the surface layer are the same.

[0019] Optionally, when the line width and line spacing of the routing lines are fixed, the first impedance and / or the second impedance is inversely proportional to the thickness of the solder resist layer;

[0020] When the first impedance and / or the second impedance is fixed, the thickness of the solder resist layer is inversely proportional to the line width, and the thickness of the solder resist layer is directly proportional to the line distance.

[0021] Optionally, reaching a preset stop condition includes:

[0022] The number of cycles exceeds the preset number;

[0023] The method further comprises:

[0024] After the number of cycles exceeds a preset number, an alarm is issued.

[0025] Optionally, after the number of cycles exceeds a preset number, issuing an alarm includes:

[0026] After the number of cycles exceeds the preset number of times, an alarm prompt message is sent to the preset display terminal to display the alarm information on the display terminal, or an alarm text message is sent to the preset mobile terminal, or a notification message carrying the alarm prompt information is sent to the preset application in the preset mobile terminal, or an instant messaging message is sent to the target contact by calling the preset instant messaging program, or an email interface is called to send the alarm information to a preset email address.

[0027] In order to solve the above technical problems, the present application also provides a printed circuit board, which can be manufactured by any of the methods described above.

[0028] Optionally, the printed circuit board includes at least one layer of inner wiring.

[0029] In order to solve the above technical problems, the present application also provides a server, which includes a printed circuit board manufactured by any of the methods described above.

[0030] To solve the above technical problems, the present application also provides a server system, the server system comprising at least one rack, such as the server described above; the rack is placed in a non-conductive coolant;

[0031] The rack includes a plurality of support plates, and one of the servers is placed on each of the support plates.

[0032] It can be seen that the printed circuit board layout determination method provided by the present application obtains the first stacking information of the printed circuit board, and based on the first stacking information, respectively calculates the impedance of the surface routing under different environments, and when the difference in impedance under the different environments is greater than a preset threshold, adjusts the parameters of the routing and increases the thickness of the solder resist layer, and re-executes the impedance calculation of the surface routing based on the first stacking information under different environments until the difference between the first impedance and the second impedance is less than or equal to the preset threshold or reaches a preset stop condition. The routing parameters and the thickness of the solder resist layer are adjusted according to the difference in impedance of the surface routing under different environments, thereby reducing the impact of different operating environments on the printed circuit board signal, and obtaining a printed circuit board that can be used in different operating environments.

[0033] The printed circuit board, server and server system provided in this application all have the above-mentioned technical effects. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the prior art and the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0035] Figure 1 A schematic diagram of a flow chart of a printed circuit board layout determination method provided in an embodiment of the present application;

[0036] Figure 2 A block diagram of a printed circuit board layout determination device provided in an embodiment of the present application;

[0037] Figure 3 A logical block diagram of a server provided in an embodiment of the present application.

[0038] Reference numerals:

[0039] 210: acquisition module; 220: calculation module; 230: determination module; 240: adjustment module; 300: server; 310: processing component; 320: power supply component; 330: network interface; 340: input / output interface; 350: memory. DETAILED DESCRIPTION

[0040] The core of this application is to provide a method for determining the layout of a printed circuit board, which can adjust the parameters of the routing and the thickness of the solder resist layer according to the impedance difference of the routing on the surface layer in different environments, thereby reducing the impact of different operating environments on the signals of the printed circuit board. Another core of this application is to provide a printed circuit board, a server, and a server system, all of which have the above-mentioned technical effects.

[0041] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0042] Please refer to Figure 1 , Figure 1 A schematic diagram of a printed circuit board layout determination method provided in an embodiment of the present application, referring to Figure 1 As shown, the method mainly includes:

[0043] S110: Acquire first stacking information of the printed circuit board;

[0044] Specifically, in this embodiment, the first stacking information includes a solder resist layer covering the surface layer;

[0045] The solder resist layer is a protective layer for a printed circuit board, and is applied to the circuits and substrates of the printed circuit board that do not need to be soldered and used as a solder resist. The purpose of applying a solder resist layer on a printed circuit board is to provide long-term protection for the routing lines after the printed circuit board lines are etched. Specifically, commonly used types of solder resists include green oil. Covering the printed circuit board with green solder resist oil can prevent the physical disconnection of the conductor circuit and the oxidation of the routing lines on the surface; secondly, covering the printed circuit board with green solder resist oil can prevent short circuits of surface devices during the welding process; thirdly, covering the printed circuit board with green solder resist oil can control welding only on the parts that must be welded, avoiding solder waste.

[0046] Wherein, in a specific implementation manner, before obtaining the first stacking information of the printed circuit board, the method further includes:

[0047] receiving stack-up configuration information of a printed circuit board;

[0048] Based on the stacking configuration information of the printed circuit board, the routing of the surface layer of the printed circuit board is modeled; wherein, during the modeling, the line width and line spacing of the routing of the surface layer are the same.

[0049] Specifically, the stacking configuration information can be a table, and the relevant parameter data is set and stored in a preset format. The parameter data may include: the thickness of the solder resist layer covering the surface of the printed circuit board, the number of stacking layers of the printed circuit board, the board type of the printed circuit board, the target board thickness of the printed circuit board, and the actual board thickness of the printed circuit board.

[0050] Specifically, in this embodiment, obtaining the first stacking information of the printed circuit board includes obtaining the stacking configuration information of the printed circuit board and the surface routing conditions of the printed circuit board, wherein the surface routing conditions of the printed circuit board include routing parameters.

[0051] Specifically, in this embodiment, the routing parameters include: line width and line spacing; wherein the line width is the width value of the routing on the surface of the printed circuit board, and the line spacing is the differential pair line spacing, and the center distance between the two lines of the differential pair is obtained by the differential pair line spacing value.

[0052] Specifically, when modeling the surface routing of the printed circuit board, a normalized design is adopted, and the line width and line spacing of the surface routing are the same.

[0053] S120: Under a first environment, calculating a first impedance of a surface wiring based on the first stacking information, and under a second environment, calculating a second impedance of the surface wiring based on the first stacking information;

[0054] Specifically, the first impedance and the second impedance of the surface wiring can be calculated by formula (1), and the formula (1) is:

[0055]

[0056] In a specific implementation manner, the differential impedance of the differential pair can be calculated by formula (2), and the formula (2) is:

[0057]

[0058] Among them, Z diff is the differential impedance, Z0 is the single-ended characteristic impedance when uncoupled, s is the trace spacing, h is the dielectric thickness between the signal line and the return path plane, w is the trace width, ε r is the relative dielectric constant of the dielectric, and t is the metal thickness, which may specifically include the sum of the metal conductor layer thickness and the copper foil thickness.

[0059] It should be noted that the above formula is an approximate formula and can be calculated by the two-dimensional field solver in the modeling software during the actual modeling process.

[0060] In a specific embodiment, the first environment is an air environment, and the second environment is a liquid environment.

[0061] Specifically, the air environment is the air environment in which the printed circuit board is located in the air-cooling heat dissipation mode; and the liquid environment is the liquid environment in which the printed circuit board is located in the immersion liquid-cooling heat dissipation mode.

[0062] Specifically, in this embodiment, the first impedance is the impedance value of the surface routing of the printed circuit board calculated based on the first stacking information in an air environment; the second impedance is the impedance value of the surface routing of the printed circuit board calculated based on the first stacking information in a liquid environment.

[0063] Specifically, in this embodiment, the printed circuit board includes inner wiring, cable (cable line) and surface wiring; wherein, the inner wiring is located inside the printed circuit board, the cable is usually used to be directly soldered on the printed circuit board or used to connect electronic devices on the printed circuit board, the cable itself is wrapped with an insulating protective layer, and the surface wiring is located on the surface of the printed circuit board. Therefore, the operating environment has little effect on the signal transmission in the inner wiring and cable of the printed circuit board, but has a greater impact on the signal transmission in the surface wiring.

[0064] Specifically, in certain specific cases, such as when the overall margin is relatively small, if the entire system is feasible to operate under air cooling conditions, then operating under liquid cooling conditions may have the risk that the signal receiving end cannot correctly identify the signal due to large signal distortion; wherein the overall margin is the degree of distortion allowed for the signal during transmission from the sending end to the receiving end while ensuring that the receiving end can correctly identify the received signal. When the signal distortion is close to the upper limit required by the standard, it indicates that the overall margin of the signal is small.

[0065] S130: Determine whether the difference between the first impedance and the second impedance is greater than a preset threshold;

[0066] Specifically, the preset threshold value can be ±10% of the first impedance. When the operating environment of the printed circuit board changes from an air environment to a liquid environment, the second impedance of the surface wiring may exceed the ±10% range of the first impedance. Therefore, when the difference between the first impedance and the second impedance is greater than the preset threshold value, the printed circuit board cannot be compatible with both the air environment and the liquid environment at the same time, and it is necessary to further adjust the parameters of the wiring and increase the thickness of the solder resist layer; when the difference between the first impedance and the second impedance is less than or equal to the preset threshold value, the printed circuit board meets the requirements of being compatible with both the air environment and the liquid environment. Of course, the specific value of the preset threshold value also needs to be set according to the margin requirements of the actual link. This is not specifically limited in the embodiments of the present application.

[0067] S140: When the difference between the first impedance and the second impedance is greater than a preset threshold, determining whether a preset stop condition is met;

[0068] Specifically, in this embodiment, the steps of calculating the first impedance of the surface routing based on the first stacking information in the first environment and calculating the second impedance of the surface routing based on the first stacking information in the second environment are re-executed until the difference between the first impedance and the second impedance is less than or equal to a preset threshold or reaches a preset stop condition, and the layout determination method ends.

[0069] Specifically, in this embodiment, the case where the difference between the first impedance and the second impedance is less than or equal to the preset threshold value means that under the first environment and the second environment, the impedance value of the printed circuit board fluctuates less due to changes in environmental conditions, that is, the printed circuit board has higher compatibility with different operating environments.

[0070] In a specific implementation, reaching a preset stop condition includes: the number of cycles exceeds a preset number; the method may further include: issuing an alarm after the number of cycles exceeds the preset number.

[0071] Specifically, the preset number of times can be set according to the feasibility of installing the printed circuit board and the target board thickness of the printed circuit board. Specifically, the routing parameters can be adjusted and the thickness of the solder resist layer can be increased without affecting the installation feasibility of the printed circuit board, so as to improve the stability of the signal transmitted by the printed circuit board under different operating environments.

[0072] Specifically, in this embodiment, when the environmental compatibility of the printed circuit board under different operating environments is still poor after the number of cycles exceeds the preset number, it can be determined that there is an abnormality in the internal components or wiring of the printed circuit board, resulting in abnormal quality of the printed circuit board, and an alarm can be issued to remind relevant personnel that there is an abnormality in the printed circuit board.

[0073] In a specific implementation manner, after the number of cycles exceeds a preset number, issuing an alarm includes:

[0074] After the number of cycles exceeds the preset number of times, an alarm prompt message is sent to the preset display terminal to display the alarm information on the display terminal, or an alarm text message is sent to the preset mobile terminal, or a notification message carrying the alarm prompt information is sent to the preset application in the preset mobile terminal, or an instant messaging message is sent to the target contact by calling the preset instant messaging program, or an email interface is called to send the alarm information to a preset email address.

[0075] Specifically, after the number of cycles exceeds the preset number, the method of issuing an alarm can be determined according to the actual operation situation, so as to be able to conveniently, in real time and accurately remind relevant personnel, including but not limited to the above-mentioned method of sending warning information. Of course, in order to ensure that relevant personnel can be reminded conveniently, in real time and accurately, a combination of multiple methods can be used to send relevant warning information. The embodiments of the present application are not limited to this.

[0076] S150: When the difference between the first impedance and the second impedance is greater than a preset threshold and a preset stop condition is not reached, adjusting the parameters of the routing and increasing the thickness of the solder resist layer;

[0077] In a specific implementation manner, the adjusting the parameters of the routing includes:

[0078] Adjust the line width and / or line spacing of the routing, wherein the line width is the width value of the surface line, and the line spacing is the differential pair line spacing.

[0079] Specifically, in this embodiment, the line width indicates the width of the trace on the surface layer of the printed circuit board, and specifically may be the width of the copper wire in the printed circuit board.

[0080] Wherein, in a specific implementation manner, before adjusting the parameters of the routing and increasing the thickness of the solder resist layer, the method may further include:

[0081] In the case where the difference between the first impedance and the second impedance is greater than a preset threshold, displaying a solder resist layer thickness setting control, wherein the solder resist layer thickness setting control is bound to the first stacking information and is used to adjust the thickness of the solder resist layer;

[0082] In case of receiving a first input to the solder resist layer thickness setting control, the input second solder resist layer is superimposed on the first solder resist layer.

[0083] Specifically, in this embodiment, the solder resist layer thickness setting control may be a two-dimensional image measuring instrument. Since the printed circuit board is a small, thin and soft product, the contact measurement method may easily cause product deformation during the measurement process, thereby causing inaccurate measurement. The two-dimensional image measuring instrument may measure the precise size of the printed circuit board in a non-contact manner, including but not limited to the solder resist layer thickness described in this embodiment.

[0084] Wherein, in a specific implementation manner, when the line width and line spacing of the routing are fixed, the first impedance and / or the second impedance is inversely proportional to the thickness of the solder resist layer;

[0085] When the first impedance and / or the second impedance is fixed, the thickness of the solder resist layer is inversely proportional to the line width, and the thickness of the solder resist layer is directly proportional to the line distance.

[0086] Specifically, it can be known from formula (1) and formula (2) that the main factors affecting the first impedance and the second impedance are the relative dielectric constant of the dielectric in the printed circuit board. Therefore, when the line width and line spacing of the printed circuit board remain unchanged, the thicker the thickness of the solder resist layer, the smaller the impedance value of the wiring on the surface of the printed circuit board. At the same time, in order to ensure that the impedance value of the surface wiring of the printed circuit board remains unchanged after the thickness of the solder resist layer increases, the line width of the surface wiring needs to be reduced and the line spacing of the surface wiring needs to be increased.

[0087] Specifically, in this embodiment, when the difference between the first impedance and the second impedance is greater than a preset threshold, the parameters of adjusting the routing and increasing the thickness of the solder resist layer can be specifically adjusted according to the operational relationship between the parameters of the surface routing and the thickness of the solder resist.

[0088] Specifically, in this embodiment, after the parameters of the routing are readjusted and the thickness of the solder resist layer is increased, the step S120 and the step S130 are re-executed.

[0089] Specifically, in this embodiment, before re-executing the calculation of the first and / or second impedance of the surface routing based on the first stack information under the first and / or second environment, the method may also include: updating the first stack information, specifically, it may include: updating the thickness of the solder resist layer, updating the line width and line spacing.

[0090] Specifically, updating the solder resist layer may be performed by adding the thickness of the newly stacked solder resist layer to the thickness of the original solder resist layer, specifically: updated solder resist layer thickness = first solder resist layer thickness + second solder resist layer thickness, and so on.

[0091] Specifically, in this embodiment, the case where the difference between the first impedance and the second impedance is greater than the preset threshold value means that under the first environment and the second environment, the impedance value of the printed circuit board fluctuates greatly due to changes in environmental conditions, that is, the printed circuit board has poor compatibility with different operating environments.

[0092] S160: End.

[0093] Specifically, when it is determined that the difference between the first impedance and the second impedance is greater than a preset threshold and a preset stop condition is reached, the layout determination process for the printed circuit board is terminated.

[0094] Specifically, when it is determined that the difference between the first impedance and the second impedance is less than or equal to a preset threshold, the layout determination process for the printed circuit board is terminated.

[0095] Specifically, when it is determined that the difference between the first impedance and the second impedance is greater than a preset threshold, the parameters of the routing and the thickness of the solder resist layer can be synchronously adjusted according to the relationship between the line width and line spacing and the thickness of the solder resist layer, and after the adjustment is completed, the line width, line spacing and the thickness of the solder resist layer parameters can be obtained to update the first stacking information, and then the steps of calculating the first impedance of the surface routing based on the updated first stacking information in the first environment and calculating the second impedance of the surface routing based on the updated first stacking information in the second environment are re-executed, and this cycle is repeated until the difference between the first impedance and the second impedance is less than or equal to the preset threshold or the preset stop condition is reached.

[0096] Specifically, in this embodiment, when the difference between the first impedance and the second impedance is less than or equal to a preset threshold value, it indicates that the printed circuit board has good compatibility with different operating environments and meets production requirements; when the preset stop condition is reached, if the difference between the first impedance and the second impedance of the printed circuit board is still greater than the preset threshold value, it indicates that there may be an abnormality inside the printed circuit board and it does not meet production requirements.

[0097] Specifically, in this embodiment, the line width and line spacing of the surface traces corresponding to the first impedance in the air environment are calculated based on the thickness of the original solder resist layer; and the second impedance of the printed circuit board in the liquid environment is calculated when the thickness of the original solder resist layer and the line width and line spacing of the surface traces remain unchanged; the change values ​​of the first impedance and the second impedance of the printed circuit board are judged when the thickness of the solder resist layer and the line width and line spacing of the surface traces remain unchanged. If the impedance change value is large (the margin of the link needs to be comprehensively judged), that is, when the difference between the first impedance and the second impedance is greater than a preset threshold, the thickness of the solder resist layer is increased by 1 mil (unit of length, mil, one thousandth of an inch), and the line width and line spacing of the surface traces corresponding to the first impedance of the printed circuit board in the air environment are reconfirmed; when the thickness of the solder resist layer is increased and the line width and line spacing of the surface traces remain unchanged, the impedance change value of the printed circuit board in the liquid environment is calculated; based on the preset threshold, it is judged whether the impedance change of the printed circuit board meets the requirements of compatibility with different operating environments under the current parameters of the solder resist layer thickness and the line width and line spacing of the surface traces.

[0098] In a specific implementation, the present application provides a method for determining a printed circuit board layout, and the specific implementation steps are as follows:

[0099] S111: Acquire first stacking information of a printed circuit board;

[0100] Specifically, in this embodiment, the stacking configuration information of the printed circuit board and the surface routing condition of the printed circuit board are obtained.

[0101] Specifically, please refer to Table 1, which is a stacking configuration information table of a printed circuit board provided in an embodiment of the present application, wherein the stacking configuration information of the printed circuit board includes: the number of layers is 8 (Layer: 8L), specifically including the top layer (TOP), 2 layers (L2), 3 layers (L3), 4 layers (L4), 5 layers (L5), 6 layers (L6), 7 layers (L7) and the bottom layer (BOT, Bottom); the substrate (Material), the substrate specifically includes a solder mask layer (Solder mask) with a thickness of 0.50mil+0.50mil (unit of length, mil, one thousandth of an inch), the solder mask is specifically green liquid (Green Liquid), a signal layer (SIGNAL), a ground layer (GND, Ground), a power layer (PWR, Power) and a chip layer (core); board type: IT-170GRA2; glass fiber cloth type (Glass Type); copper foil type (Copper Type, mainly the weight parameter of the copper foil, in ounces (oz, 1 ounce = 28.350 grams); Design Thickness, the design thickness is mainly the thickness of the prepreg (pp, Pre-pregnant); Thickness is mainly the thickness of each layer of the substrate of the printed circuit board; Total thickness is the actual thickness of the printed circuit board, which is 60.82 mil in this embodiment; Target thickness: the upper limit of the total thickness of the printed circuit board, which is 62.99 mil in this embodiment, and the tolerance of the target thickness is ±10%; Dielectric Constant (DK); and Residual copper rate; The surface treatment (Surface finished) of the printed circuit board is to cover the organic solderability preservatives (OSP).

[0102]

[0103] Table 1

[0104] Specifically, in this embodiment, the solder resist is a green liquid photo-imaging solder resist ink, hereinafter referred to as green oil, and the main components of the green oil include: epoxy and acrylic resins with photosensitive properties, such as bisphenol A epoxy resin, phenolic epoxy resin, medium phenol epoxy resin and ethyl carbamate, etc.; photoinitiators, such as thioxanthone, benzophenone, carbonyl compounds, chalcone, amino organic metal compounds, etc.; fillers, such as silica powder; hardeners, such as aromatic lipids, acid anhydrides, imidazoles; solvents, such as ether esters; defoamers, etc. The coating method generally uses screen printing, which is similar to wet film. The green oil mentioned in the chemical industry is a low-level olefin polymer, a by-product of acetylene hydrogenation, with a large viscosity, and a green oil tower must be set up for hydrogenation and deacetylation to remove it.

[0105] S121: Under an air environment, calculating a first impedance of a surface wiring based on the first stacking information, and under a liquid environment, calculating a second impedance of the surface wiring based on the first stacking information;

[0106] Specifically, in this embodiment, the process of calculating the first and / or impedance of the routing of the surface layer based on the first stacking information can be implemented by IMLC software.

[0107] Specifically, please refer to Table 2, which is a first impedance information table of a surface trace of a printed circuit board in an air environment (Air) provided in an embodiment of the present application, including: trace width and spacing; trace width (tw, trace width), differential pair width; trace spacing (ts, trace spacing), differential pair spacing; spacing (d, distance), spacing between differential pairs; solder mask layer (sm, soldermask); solder mask layer around the printed circuit board (sm beside trace); solder mask layer on the surface trace (sm above trace); solder mask layer dielectric constant (sm er); solder mask layer dielectric loss factor (sm tand); plating height (Plating Height); microstrip line (Microstrip), which represents the surface trace in this embodiment; enable air microstrip line (Enable Microstrip Air), in this embodiment, enabling the air microstrip line is represented as Enable, and disabling the air microstrip line is represented as Disable; air height (Air Height); air dielectric constant (Air er); air dielectric loss factor (Air tand); plane above microstrip air (Plane abovemicrostrip air); and impedance (model impedance).

[0108]

[0109] Table 2

[0110] Specifically, in this embodiment, the line width of the routing is 4.90 mil, the line spacing of the routing is 7.00 mil, and the thickness of the green oil is 1.9 mil+0.5 mil.

[0111] Specifically, in this embodiment, the impedance value of the first impedance of the surface wiring of the printed circuit board is calculated based on the first stacking information in an air environment to be 85.10 ohms (resistance unit, ohm).

[0112] Specifically, please refer to Table 3, which is a second impedance information table of a printed circuit board surface trace in a liquid environment (Liquid Cooling) provided in an embodiment of the present application.

[0113]

[0114] Table 3

[0115] Specifically, in this embodiment, the line width of the routing is 4.90 mil, the line spacing of the routing is 7.00 mil, and the thickness of the green oil is 1.9 mil+0.5 mil.

[0116] Specifically, in this embodiment, the impedance value of the second impedance of the surface wiring of the printed circuit board calculated based on the first stacking information is 82.10 ohms in a liquid environment.

[0117] Specifically, in this embodiment, when the line width of the routing of the printed circuit board is 4.90 mil, the line spacing of the routing is 7.00 mil, and the thickness of the green oil is 1.9 mil+0.5 mil, the difference between the first impedance and the second impedance of the printed circuit board is 3 ohm.

[0118] S131: Determine whether the difference between the first impedance and the second impedance is greater than a preset threshold;

[0119] Specifically, in this embodiment, the preset threshold is 1.5 ohms. According to step S121, the difference between the first impedance and the second impedance of the printed circuit board is 3 ohms. Therefore, the difference between the first impedance and the second impedance is greater than the preset threshold.

[0120] S141: When the difference between the first impedance and the second impedance is greater than a preset threshold, determining whether a preset stop condition is met;

[0121] Specifically, the actual thickness of the printed circuit board is 60.82 mil, which is less than the target thickness of 62.99 mil. Therefore, the preset stop condition is achieved.

[0122] S151: When the difference between the first impedance and the second impedance is greater than a preset threshold and a preset stop condition is not reached, adjusting the parameters of the routing and increasing the thickness of the solder resist layer;

[0123] Specifically, in this embodiment, when the difference between the first impedance and the second impedance is greater than a preset threshold, the parameters of the routing are adjusted and the thickness of the solder resist layer is increased. Specifically, the thickness of the green oil can be increased on the basis of the original green oil of the printed circuit board, and the line width and line spacing parameters can be adjusted.

[0124] In a specific implementation, the specific location where the green oil thickness is increased can be determined according to actual conditions. Preferably, the thickness of the green oil can be increased only at the location where the high-speed routing is located on the surface of the printed circuit board, and the thickness of the green oil at other locations can remain unchanged. The high-speed routing is a routing that transmits a higher-speed signal. The high-speed routing can be located in the inner layer routing of the printed circuit board or in the surface layer routing of the printed circuit board. The embodiments of the present application are mainly described for the high-speed routing in the routing on the surface of the printed circuit board.

[0125] Specifically, in this embodiment, please refer to Table 4, which is an impedance information table of the surface wiring in the air of a printed circuit board provided in an embodiment of the present application after adjusting the parameters of the surface wiring and increasing the thickness of the solder resist layer.

[0126]

[0127] Table 4

[0128] Specifically, in this embodiment, the line width of the routing is 4.25 mil, the line spacing of the routing is 7.65 mil, and the thickness of the green oil is 4.9 mil+3.5 mil.

[0129] Specifically, in this embodiment, the impedance value of the first impedance of the surface wiring of the printed circuit board calculated based on the updated first stacking information in an air environment is 85.09 ohms.

[0130] Specifically, in this embodiment, please refer to Table 5, which is an impedance information table of the surface wiring of a printed circuit board provided in an embodiment of the present application after adjusting the parameters of the surface wiring and increasing the thickness of the solder resist layer in the liquid.

[0131]

[0132] Table 5

[0133] Specifically, in this embodiment, the line width of the routing is 4.25 mil, the line spacing of the routing is 7.65 mil, and the thickness of the green oil is 4.9 mil+3.5 mil.

[0134] Specifically, in this embodiment, the impedance value of the first impedance of the surface wiring of the printed circuit board calculated based on the updated first stacking information in an air environment is 83.97 ohms.

[0135] Specifically, in this embodiment, when the line width of the routing of the printed circuit board is adjusted to 4.25 mil, the line spacing of the routing is adjusted to 7.65 mil, and the thickness of the green oil is increased to 4.9 mil + 3.5 mil, the difference between the first impedance and the second impedance of the printed circuit board is 1.12 ohm.

[0136] S161: End.

[0137] Specifically, in this embodiment, the preset threshold is 1.5 ohms. According to step S131, the difference between the first impedance and the second impedance of the printed circuit board is 1.12 ohms. Therefore, the difference between the first impedance and the second impedance is less than the preset threshold.

[0138] Specifically, in this embodiment, when the difference between the first impedance and the second impedance is less than a preset threshold, it indicates that the printed circuit board has good compatibility with different operating environments and meets production requirements.

[0139] In summary, the present application provides a method for determining the layout of a printed circuit board, including: obtaining first stacking information of a printed circuit board; the first stacking information includes a solder resist layer covering the surface layer; in a first environment, calculating the first impedance of the surface routing based on the first stacking information, and in a second environment, calculating the second impedance of the surface routing based on the first stacking information; when the difference between the first impedance and the second impedance is greater than a preset threshold, adjusting the parameters of the routing and increasing the thickness of the solder resist layer, and re-executing the steps of calculating the first impedance of the surface routing based on the first stacking information in the first environment and calculating the second impedance of the surface routing based on the first stacking information in the second environment, until the difference between the first impedance and the second impedance is less than or equal to the preset threshold or reaches a preset stop condition. The parameters of the routing and the thickness of the solder resist layer are adjusted according to the impedance difference of the surface routing under different environments, thereby reducing the influence of different operating environments on the printed circuit board signal, and obtaining a printed circuit board that can be used in different operating environments.

[0140] The present application also provides a printed circuit board. The printed circuit board described below can correspond to the method described above and can be manufactured by any of the methods described above.

[0141] In a specific implementation, the printed circuit board includes at least one layer of inner wiring.

[0142] This application also provides a printed circuit board layout determination device, please refer to Figure 2 , Figure 2 A block diagram of a printed circuit board layout determination device provided in an embodiment of the present application, the device comprising:

[0143] The acquisition module 210 is used to acquire first stacking information of the printed circuit board; the first stacking information includes a solder resist layer covering the surface layer;

[0144] Specifically, the acquisition module 210 includes:

[0145] An acquisition submodule, used to acquire stacking configuration information of a printed circuit board;

[0146] A calculation module 220, configured to calculate the impedance of the surface routing based on the first stacking information;

[0147] Specifically, the calculation module 220 includes:

[0148] A first calculation submodule, configured to calculate a first impedance of a surface routing line based on the first stacking information under a first environment;

[0149] A second calculation submodule, configured to calculate, under a second environment, a second impedance of the surface routing based on the first stacking information;

[0150] A determination module 230, configured to determine whether a difference between the first impedance and the second impedance is greater than a preset threshold;

[0151] An adjustment module 240, configured to adjust the parameters of the routing and increase the thickness of the solder resist layer when the difference between the first impedance and the second impedance is greater than a preset threshold;

[0152] Specifically, the adjustment module 240 includes:

[0153] A first adjustment submodule, used for adjusting the line width and / or line spacing of the routing, wherein the line width is the width value of the surface line, and the line spacing is the differential pair line spacing;

[0154] The second adjusting submodule is used to adjust the thickness of the solder resist layer.

[0155] This application also provides a server 300, please refer to Figure 3 , Figure 3 The logical block diagram of a server provided in an embodiment of the present application, the server 300 includes a processing component 310, which further includes one or more processors, and a memory resource represented by a memory 350, for storing instructions that can be executed by the processing component 310, such as an application. The application stored in the memory 350 may include one or more modules, each corresponding to a set of instructions. In addition, the processing component 310 is configured to execute instructions to perform a printed circuit board layout determination method provided in an embodiment of the present application.

[0156] The electronic device 300 may further include a power supply component 320 configured to perform power management of the electronic device 300, a wired or wireless network interface 330 configured to connect the electronic device 300 to a network, and an input / output (I / O) interface 340. The electronic device 300 may operate based on an operating system stored in the memory 350, such as Windows Server™, Mac OS X™, Unix™, Linux™, FreeBSD™ or the like.

[0157] The present application also provides a server system, the server system comprising at least one rack, such as the server described above; the rack is placed in a non-conductive cooling liquid;

[0158] In a specific implementation, the rack includes a plurality of support plates, and one server is placed on each support plate.

[0159] For an introduction to the server system provided in this application, please refer to the above method embodiment, and this application will not go into details here.

[0160] The various embodiments in the specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other. For the printed circuit board, server, and server system disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple, and the relevant parts can be referred to the method part.

[0161] The printed circuit board layout determination method, printed circuit board, server and server system provided by the present application are described in detail above. Specific examples are used herein to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method and core idea of ​​the present application. It should be pointed out that for ordinary technicians in this technical field, without departing from the principles of the present application, several improvements and modifications can be made to the present application, and these improvements and modifications also fall within the scope of protection of the claims of the present application.

Claims

1. A method for determining a printed circuit board layout, characterized in that: The method comprises: Acquire first stacking information of the printed circuit board; the first stacking information includes a solder resist layer covering the surface layer; Under a first environment, a first impedance of a surface wiring is calculated based on the first stacking information, and under a second environment, a second impedance of the surface wiring is calculated based on the first stacking information; In the case where the difference between the first impedance and the second impedance is greater than a preset threshold, adjusting the parameters of the routing and increasing the thickness of the solder resist layer, and re-performing the steps of calculating the first impedance of the routing of the surface layer based on the first stacking information under the first environment and calculating the second impedance of the routing of the surface layer based on the first stacking information under the second environment, until the difference between the first impedance and the second impedance is less than or equal to the preset threshold or a preset stop condition is reached; Wherein, the first environment is an air environment, and the second environment is a liquid environment; The adjusting of the routing parameters comprises: Adjust the line width and / or line spacing of the routing, wherein the line width is the width value of the surface line, and the line spacing is the differential pair line spacing.

2. The method according to claim 1, characterized in that Before adjusting the parameters of the routing and increasing the thickness of the solder resist layer, the method further includes: In the case where the difference between the first impedance and the second impedance is greater than a preset threshold, displaying a solder resist layer thickness setting control, wherein the solder resist layer thickness setting control is bound to the first stacking information and is used to adjust the thickness of the solder resist layer; In case of receiving a first input to the solder resist layer thickness setting control, the input second solder resist layer is superimposed on the first solder resist layer.

3. The method according to claim 1, characterized in that: Before obtaining the first stacking information of the printed circuit board, the method further includes: receiving stack-up configuration information of a printed circuit board; Based on the stacking configuration information of the printed circuit board, the routing of the surface layer of the printed circuit board is modeled; wherein, during the modeling, the line width and line spacing of the routing of the surface layer are the same.

4. The method according to claim 1, characterized in that When the line width and line spacing of the routing lines are fixed, the first impedance and / or the second impedance is inversely proportional to the thickness of the solder resist layer; When the first impedance and / or the second impedance is fixed, the thickness of the solder resist layer is inversely proportional to the line width, and the thickness of the solder resist layer is directly proportional to the line distance.

5. The method according to claim 1, characterized in that The preset stop condition is reached including: The number of cycles exceeds the preset number; The method further comprises: After the number of cycles exceeds a preset number, an alarm is issued.

6. The method according to claim 5, characterized in that The step of issuing an alarm after the number of cycles exceeds a preset number includes: After the number of cycles exceeds the preset number of times, an alarm prompt information is sent to a preset display terminal to display the alarm prompt information on the display terminal, or an alarm text message is sent to a preset mobile terminal, or a notification message carrying the alarm prompt information is sent to a preset application in the preset mobile terminal, or an instant messaging message is sent to a target contact by calling a preset instant messaging program, or an email interface is called to send the alarm information to a preset email address.

7. A printed circuit board, characterized in that: The method according to any one of claims 1 to 6 is used for manufacturing.

8. The printed circuit board according to claim 7, characterized in that: The printed circuit board includes at least one inner wiring layer.

9. A server, characterized in that: Comprising the printed circuit board as claimed in claim 7.

10. A server system, characterized in that: The server comprises at least one rack, wherein the rack is placed in a non-conductive cooling liquid; The rack includes a plurality of support plates, and one of the servers is placed on each of the support plates.

Images