A method and device for changing the instantaneous impedance of a PCB link

Abstract

The present invention discloses a method and device for changing the instantaneous impedance of a PCB link. The method determines the capacitance value of the parasitic capacitance of a branch transmission line on a printed circuit board (PCB), determines the inductance value of an inductor configured on the branch transmission line based on the capacitance value, calculates the instantaneous impedance value of the main transmission line on the PCB based on the inductance value, and increases the inductance value according to a preset adjustment rule until the decrease amplitude of the instantaneous impedance value is within a preset amplitude range, thereby obtaining the increased inductance value. Thus, by adding an inductor to the branch transmission line, and increasing the inductance value of the added inductor until the decrease amplitude of the instantaneous impedance value is within a preset amplitude range, the increased inductance value is obtained, thereby controlling the inductance value of the branch transmission line to reduce the influence of the branch transmission line on the instantaneous impedance of the main transmission line, so that the instantaneous impedance of the main transmission line is stable, thereby reducing reflections, and ensuring the signal quality and signal integrity of the overall PCB link.

Description

Technical Field

[0001] The present invention relates to the field of instantaneous impedance technology, and in particular to a method and device for changing the instantaneous impedance of a PCB link. Background Art

[0002] With the development of high-speed signals, impedance control becomes more and more important.

[0003] This is because the signal transmission rate is getting faster and faster, the rising and falling edges of the signal are becoming steeper and steeper, and the frequency is becoming higher and higher. These factors will cause interference and reflection problems in the signal transmission process. Therefore, as the high-speed signal rate becomes higher and higher, the control of impedance becomes more and more stringent.

[0004] In a PCB (Printed Circuit Board) link with branch transmission lines, the impedance of the branch transmission lines on the main transmission lines has an increasing impact, which leads to severe signal reflections, thus affecting the signal quality and signal integrity of the entire PCB link. Summary of the invention

[0005] The present invention provides a method and device for changing the instantaneous impedance of a PCB link, which can ensure the signal quality and signal integrity of the entire PCB link. The specific technical solution is as follows.

[0006] In a first aspect, the present invention provides a method for changing the instantaneous impedance of a PCB link, the method comprising:

[0007] Determine the capacitance value of the parasitic capacitance of the branch transmission line on the printed circuit board PCB;

[0008] Determine the inductance value of the inductor configured on the branch transmission line based on the capacitance value;

[0009] Calculating the instantaneous impedance value of the main transmission line on the PCB board based on the inductance value;

[0010] The inductance value is increased according to a preset adjustment rule until the decrease amplitude of the instantaneous impedance value is within a preset amplitude range, thereby obtaining the increased inductance value.

[0011] Optionally, the step of determining the capacitance value of the parasitic capacitance of the branch transmission line on the printed circuit board PCB comprises:

[0012] Receiving a length value of a branch transmission line on the PCB board;

[0013] The capacitance value of the parasitic capacitance of the branch transmission line is obtained according to the length value and a preset capacitance calculation formula.

[0014] Optionally, the step of determining the inductance value of the inductor configured on the branch transmission line based on the capacitance value includes:

[0015] receiving an impedance value of the branch transmission line;

[0016] The inductance value of the inductor configured on the branch transmission line is calculated according to the capacitance value and the impedance value.

[0017] Optionally, the step of calculating the instantaneous impedance value of the trunk transmission line on the PCB board based on the inductance value includes:

[0018] The instantaneous impedance value of the trunk transmission line on the PCB board is obtained by performing simulation calculation based on the inductance value and the impedance simulation software, wherein the impedance simulation software is used to obtain the instantaneous impedance value based on the inductance value simulation calculation.

[0019] Optionally, the step of increasing the inductance value of the inductor according to a preset adjustment rule until the decrease amplitude of the instantaneous impedance value is within a preset amplitude range to obtain the increased inductance value includes:

[0020] The inductance value of the inductor is increased according to a preset adjustment range until the decrease range of the instantaneous impedance value is within a preset range, thereby obtaining the increased inductance value.

[0021] In a second aspect, the present invention provides a device for changing the instantaneous impedance of a PCB link, the device comprising:

[0022] A capacitance value determination module, used to determine the capacitance value of the parasitic capacitance of the branch transmission line on the printed circuit board PCB;

[0023] A first inductance value determination module, configured to determine the inductance value of the inductor configured on the branch transmission line based on the capacitance value;

[0024] An instantaneous impedance value determination module is used to calculate the instantaneous impedance value of the trunk transmission line on the PCB board based on the inductance value;

[0025] The second inductance value determination module is used to increase the inductance value according to a preset adjustment rule until the decrease amplitude of the instantaneous impedance value is within a preset amplitude range, thereby obtaining the increased inductance value.

[0026] Optionally, the capacitance value determining module includes:

[0027] A first receiving submodule, used for receiving the length value of the branch transmission line on the PCB board;

[0028] The first calculation submodule is used to obtain the capacitance value of the parasitic capacitance of the branch transmission line according to the length value and a preset capacitance calculation formula.

[0029] Optionally, the first inductance value determining module includes:

[0030] A second receiving submodule, used to receive the impedance value of the branch transmission line;

[0031] The second calculation submodule is used to calculate the inductance value of the inductor configured on the branch transmission line according to the capacitance value and the impedance value.

[0032] Optionally, the instantaneous impedance value determination module is specifically used to:

[0033] The instantaneous impedance value of the trunk transmission line on the PCB board is obtained by performing simulation calculation based on the inductance value and the impedance simulation software, wherein the impedance simulation software is used to obtain the instantaneous impedance value based on the inductance value simulation calculation.

[0034] Optionally, the second inductance value determining module is specifically used to:

[0035] The inductance value of the inductor is increased according to a preset adjustment range until the decrease range of the instantaneous impedance value is within a preset range, thereby obtaining the increased inductance value.

[0036] As can be seen from the above content, a method and device for changing the instantaneous impedance of a PCB link provided by an embodiment of the present invention can determine the capacitance value of the parasitic capacitance of a branch transmission line on a printed circuit board PCB, determine the inductance value of the inductor configured on the branch transmission line based on the capacitance value, calculate the instantaneous impedance value of the main transmission line on the PCB based on the inductance value, and increase the inductance value according to a preset adjustment rule until the decrease amplitude of the instantaneous impedance value is within a preset amplitude range, thereby obtaining the increased inductance value. Thus, by adding an inductor to the branch transmission line, and by increasing the inductance value of the added inductor until the decrease amplitude of the instantaneous impedance value is within a preset amplitude range, the increased inductance value is obtained, thereby controlling the inductance value of the branch transmission line to reduce the influence of the branch transmission line on the instantaneous impedance of the main transmission line, so that the instantaneous impedance of the main transmission line is stable, thereby reducing reflections, and ensuring the signal quality and signal integrity of the overall PCB link.

[0037] The innovative features of the embodiments of the present invention include:

[0038] 1. By adding inductance to the branch transmission line and increasing the inductance value of the added inductance until the decrease in the instantaneous impedance value is within the preset range, the inductance value of the branch transmission line is controlled to reduce the impact of the branch transmission line on the instantaneous impedance of the trunk transmission line, so that the instantaneous impedance of the trunk transmission line is stable, thereby reducing reflections and ensuring the signal quality and signal integrity of the overall PCB link.

[0039] 2. Through simulation calculation, the instantaneous impedance value of the main transmission line on the PCB board is obtained based on the inductance value of the inductor configured on the branch transmission line, thereby reducing costs.

[0040] Of course, it is not necessary to achieve all of the advantages described above at the same time to implement any product or method of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the prior art descriptions. Obviously, the drawings described below are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can also be obtained based on these drawings without creative work.

[0042] Figure 1 A schematic flow chart of a method for changing the instantaneous impedance of a PCB link provided by an embodiment of the present invention;

[0043] Figure 2 It is a schematic diagram of the instantaneous impedance value of the trunk transmission line when the inductance value is 5nH;

[0044] Figure 3 A schematic diagram of a simulation object model provided by an embodiment of the present invention;

[0045] Figure 4 It is a schematic diagram of the instantaneous impedance value of the trunk transmission line when the inductance value is 100nH;

[0046] Figure 5 A schematic structural diagram of a device for changing the instantaneous impedance of a PCB link provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0047] The following will be combined with the accompanying drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0048] It should be noted that the terms "including" and "having" and any variations thereof in the embodiments of the present invention and the accompanying drawings are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device comprising a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to these processes, methods, products or devices.

[0049] The embodiment of the present invention discloses a method and device for changing the instantaneous impedance of a PCB link, which can ensure the signal quality and signal integrity of the entire PCB link. The embodiment of the present invention is described in detail below.

[0050] Figure 1 A flow chart of a method for changing the instantaneous impedance of a PCB link provided by an embodiment of the present invention. The method is applied to electronic equipment. The method specifically includes the following steps.

[0051] S110: Determine the capacitance value of the parasitic capacitance of the branch transmission line on the printed circuit board PCB.

[0052] A PCB (Printed Circuit Board) link includes a trunk transmission line and a branch transmission line. In an embodiment of the present invention, the influence of the branch transmission line on the impedance of the trunk transmission line is changed by adding inductance to the branch transmission line.

[0053] In order to achieve this goal, it is necessary to determine the capacitance value of the parasitic capacitance of the branch transmission line on the printed circuit board PCB.

[0054] The above step S110 may include:

[0055] Receive the length value of the branch transmission line on the PCB board;

[0056] The capacitance value of the parasitic capacitance of the branch transmission line is obtained according to the length value and a preset capacitance calculation formula.

[0057] In order to determine the capacitance value of the parasitic capacitance of the branch transmission line, the tester can input the length value of the branch transmission line into the electronic device, the electronic device receives the length value of the branch transmission line on the PCB board, and then obtains the capacitance value of the parasitic capacitance of the branch transmission line based on the length value and the preset capacitance calculation formula.

[0058] Specifically, the capacitance value is calculated as:

[0059] C=ε0ε r *S / d

[0060] Where C is the capacitance value of the parasitic capacitance of the branch transmission line, ε0 is the vacuum dielectric constant, ε r is the relative dielectric constant, S is the area of ​​the branch transmission line, and d is the thickness of the PCB board.

[0061] Here, the edge effect is ignored for equivalent calculation. S can be calculated based on the line width and line length of the branch transmission line, and d can be calculated based on the specific conditions of different PCB boards.

[0062] For example, the commonly used material for PCB board is glass fiber, ε r It can be taken as 4.2, and ε0 is 8.854187817×10 -12 F / m, the common plate thickness is 1~1.6mm, here d is 1.6mm.

[0063] For example: Assuming that the length of the branch transmission line on the PCB board is 20 mil, according to the capacitance calculation formula, the capacitance value of the parasitic capacitance of the branch transmission line is calculated to be 0.002 pF.

[0064] S120: Determine the inductance value of the inductor configured on the branch transmission line based on the capacitance value.

[0065] After the capacitance value is determined, it is necessary to determine the inductance value of the inductor configured on the branch transmission line.

[0066] The above step S120 may include:

[0067] The impedance value of the receiving branch transmission line;

[0068] The inductance value of the inductor configured on the branch transmission line is calculated based on the capacitance value and the impedance value.

[0069] Similarly, in order to determine the inductance value of the inductor configured on the branch transmission line, the tester can input the impedance value of the branch transmission line into an electronic device, the electronic device receives the impedance value of the branch transmission line, and then calculates the inductance value of the inductor configured on the branch transmission line based on the capacitance value and the impedance value.

[0070] Specifically, the calculation formula for the inductance value is:

[0071]

[0072] Among them, Z is the impedance value, C is the capacitance value, and L is the inductance value.

[0073] For example, following the example of step S110, assuming that the impedance value of the branch transmission line is 50Ω, the inductance value calculated according to the above formula is 5nH.

[0074] S130: Calculate the instantaneous impedance value of the main transmission line on the PCB board based on the inductance value.

[0075] In order to determine the influence of the inductance value of the inductor configured on the branch transmission line on the impedance of the main transmission line, after obtaining the inductance value of the inductor configured on the branch transmission line, it is necessary to calculate the instantaneous impedance value of the main transmission line on the PCB board based on the inductance value.

[0076] The above step S130 may include:

[0077] The instantaneous impedance value of the trunk transmission line on the PCB board is obtained by performing simulation calculation based on the inductance value and impedance simulation software, wherein the impedance simulation software is used to obtain the instantaneous impedance value based on the inductance value simulation calculation.

[0078] Therefore, by means of simulation calculation, the instantaneous impedance value of the main transmission line on the PCB board can be obtained based on the inductance value of the inductor configured on the branch transmission line, thereby reducing costs.

[0079] For example, following the example of step S120, the inductance value of 5nH is input into the impedance simulation software to obtain the instantaneous impedance value of the main transmission line on the PCB board as follows: Figure 2 As shown, Figure 2 This is a schematic diagram of the instantaneous impedance value of the trunk transmission line when the inductance value is 5nH. Figure 2 In the figure, the horizontal axis is time and the vertical axis is impedance, see Figure 2 , we can see that at this time, the instantaneous impedance value of the trunk transmission line is about 25Ω;

[0080] In theory, the instantaneous impedance value of the trunk transmission line can be calculated according to the following resistor parallel formula:

[0081] R0=(R1*R2) / (R1+R2)

[0082] Among them, R0 is the instantaneous impedance of the PCB link, R1 is the impedance of the branch transmission line, and R2 is the impedance of the trunk transmission line;

[0083] Assuming that the value of R2 is 50Ω and the value of R1 is 50Ω, the calculated value of R0 is 25Ω. At this time, the instantaneous impedance of the PCB link is similar to the instantaneous impedance of the trunk transmission line. Therefore, the instantaneous impedance value of the trunk transmission line is approximately 25Ω. It can be seen that it is consistent with the instantaneous impedance value of the trunk transmission line obtained in the impedance simulation software. Therefore, it proves that the simulation results of the impedance simulation software are correct.

[0084] It can be seen that the inductance value of the inductor configured on the branch transmission line can affect the instantaneous impedance value of the trunk transmission line.

[0085] S140: increasing the inductance value according to a preset adjustment rule until the decrease amplitude of the instantaneous impedance value is within a preset amplitude range, thereby obtaining the increased inductance value.

[0086] Since the inductance value of the inductor configured on the branch transmission line can affect the instantaneous impedance value of the trunk transmission line, and according to the formula It can be seen that as the inductance value increases, the impedance value increases. Therefore, in order to prevent the branch transmission line from having a significant impact on the impedance of the main transmission line, it is necessary to increase the inductance value of the inductor configured on the branch transmission line, that is, to increase the inductance value according to the preset adjustment rules until the decrease in the instantaneous impedance value is within the preset amplitude range, thereby obtaining the increased inductance value.

[0087] Wherein, step S140 may include:

[0088] The inductance value of the inductor is increased according to the preset adjustment range until the decrease range of the instantaneous impedance value is within the preset range, thereby obtaining the increased inductance value.

[0089] The adjustment range can be determined according to actual conditions, and for example, the adjustment range is 5nH or 10nH. The preset range is 5%-10%.

[0090] When the decrease in the instantaneous impedance value is within the preset range, it means that the influence of the branch transmission line on the impedance of the main transmission line is very small, almost non-existent. At this time, the adjusted inductance value is the inductance value of the inductor that can actually be installed on the branch transmission line. After the inductor with this inductance value is installed on the branch transmission line, the branch transmission line has basically no influence on the impedance of the main transmission line.

[0091] It can be known from the above content that the embodiment of the present invention can determine the capacitance value of the parasitic capacitance of the branch transmission line on the printed circuit board PCB, determine the inductance value of the inductor configured on the branch transmission line based on the capacitance value, calculate the instantaneous impedance value of the main transmission line on the PCB based on the inductance value, and increase the inductance value according to the preset adjustment rule until the decrease amplitude of the instantaneous impedance value is within the preset amplitude range, and obtain the increased inductance value. Therefore, by adding inductance to the branch transmission line, and by increasing the inductance value of the added inductance until the decrease amplitude of the instantaneous impedance value is within the preset amplitude range, the increased inductance value is obtained, so as to control the inductance value of the branch transmission line to reduce the influence of the branch transmission line on the instantaneous impedance of the main transmission line, so that the instantaneous impedance of the main transmission line is stable, thereby reducing reflections and ensuring the signal quality and signal integrity of the overall PCB link.

[0092] For ease of understanding, a method for changing the instantaneous impedance of a PCB link provided by the present invention is described in detail below through a specific embodiment:

[0093] 1. Select the branch transmission line as the simulation object and select the inductor as the introduced variable.

[0094] Figure 3 A schematic diagram of a simulation object model provided by an embodiment of the present invention, see Figure 3The horizontal line is the trunk transmission line, and the vertical line is the branch transmission line. The branch transmission line divides the trunk transmission line into two sections: link one trace1 and link two trace2. Link three trace3 is the branch transmission line. The branch transmission line is provided with an inductor, that is, the inductor is selected as the introduced variable.

[0095] Since the inductance value of the introduced inductor 1 is relatively large, much larger than the parasitic inductance of the branch transmission line, the parasitic inductance can be ignored.

[0096] Assume that the impedance of the high-speed signal is 50Ω, and the PCB board is a 4-layer board. The board thickness is set as shown in the following table:

[0097]

[0098] From the table, we can see the material and thickness settings of the four layers L1-L4 of the PCB board, as well as the material and thickness settings of the interlayer PP and interlayer core board between the boards. The impedance of the trunk transmission line is 50Ω and the line width is 5.62mil.

[0099] 2. Analyze the impact of the inductance value on the instantaneous impedance of the trunk transmission line.

[0100] Assuming that the length of the branch transmission line on the PCB board is 20mil, according to the calculation formula of the capacitance value, see above for details, the capacitance value of the parasitic capacitance of the branch transmission line is calculated to be 0.002pF. Assuming that the impedance value of the branch transmission line is 50Ω, according to the above calculation formula of the inductance value, the inductance value is calculated to be 5nH.

[0101] Input the inductance value of 5nH into the impedance simulation software to obtain the instantaneous impedance value of the main transmission line on the PCB board as follows Figure 2 As shown, it can be seen that at this time, the instantaneous impedance value of the trunk transmission line is approximately 25Ω.

[0102] In theory, the instantaneous impedance value of the trunk transmission line can be calculated according to the following resistor parallel formula:

[0103] R0=(R1*R2) / (R1+R2)

[0104] Among them, R0 is the instantaneous impedance of the PCB link, R1 is the impedance of the branch transmission line, and R2 is the impedance of the trunk transmission line;

[0105] Assuming that the value of R2 is 50Ω and the value of R1 is 50Ω, the calculated value of R0 is 25Ω. At this time, the instantaneous impedance of the PCB link is similar to the instantaneous impedance of the trunk transmission line. Therefore, the instantaneous impedance value of the trunk transmission line is approximately 25Ω. It can be seen that it is consistent with the instantaneous impedance value of the trunk transmission line obtained in the impedance simulation software. Therefore, it proves that the simulation results of the impedance simulation software are correct.

[0106] It can be seen that the inductance value of the inductor configured on the branch transmission line can affect the instantaneous impedance value of the trunk transmission line.

[0107] 3. Select the appropriate inductance value of the branch transmission line based on the change in instantaneous impedance.

[0108] Since the inductance value of the inductor configured on the branch transmission line can affect the instantaneous impedance value of the trunk transmission line, and according to the formula It can be seen that as the inductance value increases, the impedance value increases. Therefore, in order to prevent the branch transmission line from having a significant impact on the impedance of the main transmission line, it is necessary to increase the inductance value of the inductor configured on the branch transmission line, that is, to increase the inductance value according to the preset adjustment rules until the decrease in the instantaneous impedance value is within the preset amplitude range, thereby obtaining the increased inductance value.

[0109] Assuming that the inductance value is increased from 5nH to 100nH, the instantaneous impedance value of the main transmission line on the PCB board is obtained as follows: Figure 4 As shown, Figure 4 This is a schematic diagram of the instantaneous impedance value of the trunk transmission line when the inductance value is 100nH. Figure 4 In the figure, the horizontal axis is time and the vertical axis is impedance.

[0110] See also Figure 4 It can be seen that at this time, the decrease in the instantaneous impedance value of the trunk transmission line is relatively low and within the preset amplitude range, which means that at this time, the influence of the branch transmission line on the instantaneous impedance of the trunk transmission line is relatively low and meets the requirements. A 100nH inductor can be installed on the branch transmission line. The branch transmission line has basically no influence on the impedance of the trunk transmission line.

[0111] Figure 5 A schematic diagram of a device for changing the instantaneous impedance of a PCB link provided by an embodiment of the present invention, see Figure 5 , a device for changing the instantaneous impedance of a PCB link provided by an embodiment of the present invention comprises:

[0112] A capacitance value determination module 510 is used to determine the capacitance value of the parasitic capacitance of the branch transmission line on the printed circuit board PCB;

[0113] A first inductance value determination module 520, configured to determine the inductance value of the inductor configured on the branch transmission line based on the capacitance value;

[0114] An instantaneous impedance value determination module 530 is used to calculate the instantaneous impedance value of the trunk transmission line on the PCB board based on the inductance value;

[0115] The second inductance value determination module 540 is used to increase the inductance value according to a preset adjustment rule until the decrease amplitude of the instantaneous impedance value is within a preset amplitude range, thereby obtaining the increased inductance value.

[0116] Therefore, the device provided by the embodiment of the present invention can determine the capacitance value of the parasitic capacitance of the branch transmission line on the printed circuit board PCB, determine the inductance value of the inductor configured on the branch transmission line based on the capacitance value, calculate the instantaneous impedance value of the main transmission line on the PCB based on the inductance value, and increase the inductance value according to the preset adjustment rule until the decrease amplitude of the instantaneous impedance value is within the preset amplitude range, and obtain the increased inductance value. Therefore, by adding inductance to the branch transmission line, and by increasing the inductance value of the added inductance until the decrease amplitude of the instantaneous impedance value is within the preset amplitude range, the increased inductance value is obtained, so as to control the inductance value of the branch transmission line to reduce the influence of the branch transmission line on the instantaneous impedance of the main transmission line, so that the instantaneous impedance of the main transmission line is stable, thereby reducing reflections and ensuring the signal quality and signal integrity of the overall PCB link.

[0117] In one implementation, the capacitance value determining module 510 may include:

[0118] A first receiving submodule, used for receiving the length value of the branch transmission line on the PCB board;

[0119] The first calculation submodule is used to obtain the capacitance value of the parasitic capacitance of the branch transmission line according to the length value and a preset capacitance calculation formula.

[0120] In one implementation, the first inductance value determining module 520 may include:

[0121] A second receiving submodule, used to receive the impedance value of the branch transmission line;

[0122] The second calculation submodule is used to calculate the inductance value of the inductor configured on the branch transmission line according to the capacitance value and the impedance value.

[0123] In one implementation, the instantaneous impedance value determination module 530 may be specifically used to:

[0124] The instantaneous impedance value of the trunk transmission line on the PCB board is obtained by performing simulation calculation based on the inductance value and the impedance simulation software, wherein the impedance simulation software is used to obtain the instantaneous impedance value based on the inductance value simulation calculation.

[0125] In one implementation, the second inductance value determining module 540 may be specifically configured to:

[0126] The inductance value of the inductor is increased according to a preset adjustment range until the decrease range of the instantaneous impedance value is within a preset range, thereby obtaining the increased inductance value.

[0127] The above device embodiment corresponds to the method embodiment and has the same technical effect as the method embodiment. For specific description, please refer to the method embodiment. The device embodiment is obtained based on the method embodiment. For specific description, please refer to the method embodiment part, which will not be repeated here.

[0128] Those skilled in the art can understand that the accompanying drawings are only schematic diagrams of an embodiment, and the modules or processes in the accompanying drawings are not necessarily required to implement the present invention.

[0129] Those skilled in the art can understand that the modules in the device in the embodiment can be distributed in the device in the embodiment according to the description of the embodiment, or can be changed accordingly and located in one or more devices different from the embodiment. The modules in the above embodiment can be combined into one module, or can be further divided into multiple sub-modules.

[0130] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for changing the instantaneous impedance of a PCB link, characterized in that: The method comprises: Determine the capacitance value of the parasitic capacitance of the branch transmission line on the printed circuit board PCB; Determine the inductance value of the inductor configured on the branch transmission line based on the capacitance value; Calculating the instantaneous impedance value of the main transmission line on the PCB board based on the inductance value; The inductance value is increased according to a preset adjustment rule until the decrease amplitude of the instantaneous impedance value is within a preset amplitude range, thereby obtaining the increased inductance value.

2. The method according to claim 1, characterized in that The step of determining the capacitance value of the parasitic capacitance of the branch transmission line on the printed circuit board PCB comprises: Receiving a length value of a branch transmission line on the PCB board; The capacitance value of the parasitic capacitance of the branch transmission line is obtained according to the length value and a preset capacitance calculation formula.

3. The method according to claim 1, characterized in that The step of determining the inductance value of the inductor configured on the branch transmission line based on the capacitance value comprises: receiving an impedance value of the branch transmission line; The inductance value of the inductor configured on the branch transmission line is calculated according to the capacitance value and the impedance value.

4. The method according to claim 1, characterized in that The step of calculating the instantaneous impedance value of the trunk transmission line on the PCB board based on the inductance value comprises: The instantaneous impedance value of the trunk transmission line on the PCB board is obtained by performing simulation calculation based on the inductance value and the impedance simulation software, wherein the impedance simulation software is used to obtain the instantaneous impedance value based on the inductance value simulation calculation.

5. The method according to claim 1, characterized in that The step of increasing the inductance value of the inductor according to the preset adjustment rule until the decrease amplitude of the instantaneous impedance value is within the preset amplitude range to obtain the increased inductance value includes: The inductance value of the inductor is increased according to a preset adjustment range until the decrease range of the instantaneous impedance value is within a preset range, thereby obtaining the increased inductance value.

6. A device for changing the instantaneous impedance of a PCB link, characterized in that: The device comprises: A capacitance value determination module, used to determine the capacitance value of the parasitic capacitance of the branch transmission line on the printed circuit board PCB; A first inductance value determination module, configured to determine the inductance value of the inductor configured on the branch transmission line based on the capacitance value; An instantaneous impedance value determination module is used to calculate the instantaneous impedance value of the trunk transmission line on the PCB board based on the inductance value; The second inductance value determination module is used to increase the inductance value according to a preset adjustment rule until the decrease amplitude of the instantaneous impedance value is within a preset amplitude range, thereby obtaining the increased inductance value.

7. The device according to claim 6, characterized in that The capacitance value determination module comprises: A first receiving submodule, used for receiving the length value of the branch transmission line on the PCB board; The first calculation submodule is used to obtain the capacitance value of the parasitic capacitance of the branch transmission line according to the length value and a preset capacitance calculation formula.

8. The device according to claim 6, characterized in that The first inductance value determining module includes: A second receiving submodule, used to receive the impedance value of the branch transmission line; The second calculation submodule is used to calculate the inductance value of the inductor configured on the branch transmission line according to the capacitance value and the impedance value.

9. The device according to claim 6, characterized in that The instantaneous impedance value determination module is specifically used for: The instantaneous impedance value of the trunk transmission line on the PCB board is obtained by performing simulation calculation based on the inductance value and the impedance simulation software, wherein the impedance simulation software is used to obtain the instantaneous impedance value based on the inductance value simulation calculation.

10. The device according to claim 6, characterized in that The second inductance value determining module is specifically used for: The inductance value of the inductor is increased according to a preset adjustment range until the decrease range of the instantaneous impedance value is within a preset range, thereby obtaining the increased inductance value.

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