Printed circuit board, server, wiring compensation method, device, equipment and medium

Abstract

The invention discloses a printed circuit board, a server, a wiring compensation method and device, equipment and a medium, and relates to the technical field of circuit boards, and the printed circuit board is provided with at least two signal transmission lines; each signal transmission line comprises a plurality of transmission line sections which are connected in sequence, different transmission line sections of the same signal transmission line have different unit length transmission time delays, the transmission line sections of different signal transmission lines are oppositely arranged, and the unit length transmission time delays of the opposite transmission line sections are the same; any two opposite transmission line segments are a transmission line segment to be adjusted and a target transmission line segment, the transmission line segment to be adjusted further comprises a plurality of compensation line segments, and the compensation line segments are inserted between parallel segments of the transmission line segment to be adjusted so that the lengths of any two opposite transmission line segments can be the same. According to the invention, the consistency of signal transmission delays of the two signal transmission lines is ensured, and signals transmitted by the two signal transmission lines arrive at the same time, so that the signal integrity design quality can be greatly improved.

Description

Technical Field

[0001] The present application relates to the field of circuit design technology, and in particular to a printed circuit board, a server, a wiring compensation method, a device, a device, and a medium. Background Art

[0002] With the advancement of semiconductor technology and the growth of application demand, signal rates are getting faster and faster, which brings higher and higher requirements to signal integrity design. Existing high-speed signals are all transmitted in differential form. When designing high-speed signal transmission lines, related technologies control the total length of the two signal transmission lines to be equal to ensure that the signals transmitted by the two signal transmission lines arrive at the receiving end at the same time from the transmitting end, thereby avoiding sampling errors caused by timing offset. Existing designs often only focus on overall equal length design, believing that as long as the overall length of the two signal transmission lines is equal, the delay can be consistent. However, it ignores the fact that the transmission delay per unit length of the signal transmission line in different areas of the circuit board is inconsistent. Therefore, although the wiring is equal in length, it cannot guarantee that the two differential signals arrive at the receiving end at the same time, which will lead to signal integrity problems such as high bit error rate, increased common mode noise, and eye diagram collapse. Summary of the Invention

[0003] The present application provides a printed circuit board, a server, a wiring compensation method, an apparatus, a device and a medium to at least solve the technical problem in the related art that two differential signals cannot be guaranteed to arrive at the same time.

[0004] The present application provides a printed circuit board, on which at least two signal transmission lines are provided; The signal transmission line includes a plurality of sequentially connected transmission line segments. Different transmission line segments of the same signal transmission line have different transmission delays per unit length. Transmission line segments of different signal transmission lines are arranged relative to each other and have the same transmission delay per unit length. Any two opposing transmission line segments are a transmission line segment to be adjusted and a target transmission line segment. Both the transmission line segment to be adjusted and the target transmission line segment include parallel segments. The length of the parallel segments of the transmission line segment to be adjusted is less than the length of the parallel segments of the target transmission line segment. The transmission line segment to be adjusted also includes a plurality of compensation segments. The compensation segments are inserted between the parallel segments of the transmission line segment to be adjusted so that the lengths of any two opposing transmission line segments are the same.

[0005] The present application also provides a server, comprising any of the above-mentioned printed circuit boards.

[0006] The present application also provides a wiring compensation design method, which is applied to design any of the above-mentioned printed circuit boards, and the method comprises: Dividing the signal transmission line into a plurality of sequentially connected transmission line segments according to preset delay characteristics of the signal transmission line in different areas of the printed circuit board, wherein different transmission line segments of the same signal transmission line have different transmission delays per unit length, and transmission line segments of different signal transmission lines are arranged relative to each other and have the same transmission delay per unit length; The two opposite transmission line segments are routed for compensation so that the lengths of any two opposite transmission line segments are equal.

[0007] The present application also provides a wiring compensation design device, which is used to design any of the above-mentioned printed circuit boards, and the device includes: A transmission line segmentation module is used to divide the signal transmission line into a number of sequentially connected transmission line segments based on preset delay characteristics of the signal transmission line in different areas of the printed circuit board, wherein different transmission line segments of the same signal transmission line have different transmission delays per unit length, and transmission line segments of different signal transmission lines are arranged relative to each other and have the same transmission delay per unit length; The segment compensation module is used to perform wiring compensation on two opposite transmission line segments so that the lengths of any two opposite transmission line segments are equal.

[0008] The present application also provides an electronic device, comprising: Memory for storing computer programs; The processor is used to implement the steps of the wiring compensation design method as described above when executing a computer program.

[0009] The present application also provides a computer-readable storage medium, in which a computer program is stored. When the computer program is executed by a processor, the steps of the wiring compensation design method as described above are implemented.

[0010] The present application also provides a computer program product, comprising computer instructions, which are used to enable a computer to execute the steps of the wiring compensation design method as described above.

[0011] In this application, by setting the transmission line segments with different unit length transmission delays in the two signal transmission lines to be of equal length, the signal transmission lines are designed to be segmented and of equal length in different areas, thereby ensuring the consistency of the signal transmission delays of the two signal transmission lines, and the signals transmitted by the two signal transmission lines arrive at the same time, thereby greatly improving the signal integrity design quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] In order to more clearly illustrate the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments. 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 any creative work.

[0013] Figure 1 Schematic diagram of the design of differential signal lines in related technology; Figure 2 Schematic diagram of the structure of the differential signal line connection part in the related art; Figure 3 This is a schematic structural diagram of a printed circuit board in an embodiment of the present application; Figure 4 This is a schematic structural diagram of another printed circuit board in an embodiment of the present application; Figure 5 This is a structural diagram of another printed circuit board in an embodiment of the present application; Figure 6 This is a schematic structural diagram of a compensation line segment of a trapezoidal structure in an embodiment of the present application; Figure 7 This is a schematic diagram of the structure of the compensation line segment of the straight chamfer in the embodiment of the present application; Figure 8 This is a schematic structural diagram of the compensation line segment of the arc chamfer in an embodiment of the present application; Figure 9 This is a schematic structural diagram of a compensation line segment of an arc structure in an embodiment of the present application; Figure 10 This is a schematic structural diagram of a compensation line segment of a wedge-shaped structure in an embodiment of the present application; Figure 11 This is a schematic structural diagram of the connection portion of the signal transmission line in an embodiment of the present application; Figure 12 This is a flow chart of a wiring compensation design method according to an embodiment of the present application; Figure 13 This is a schematic structural diagram of a wiring compensation design device in an embodiment of the present application; Figure 14 This is a schematic diagram of the structure of an electronic device in an embodiment of the present application.

[0014] Description of reference numerals: 1. First transmission line segment; 2. Second transmission line segment; 3. Compensation line segment; 4. Third transmission line segment; 5. First electronic component; 6. Second electronic component; 7. Fourth transmission line segment; 8. Fifth transmission line segment; 9. Gradient line segment; 31. First connecting line segment; 32. Middle line segment; 33. Second connecting line segment; 311. First chamfered line segment; 312. First main line segment; 313. Second chamfered line segment; 331. Third chamfered line segment; 332. Second main line segment; 333. Fourth chamfered line segment. DETAILED DESCRIPTION

[0015] The following will be combined with the accompanying drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of them. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0016] It should be noted that the terms "length," "width," "upper," "lower," and the like indicate positions or relationships based on those shown in the accompanying drawings and are intended only to facilitate the description of this application and simplify the description. They are not intended to indicate or imply that the devices or components referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limiting this application. The terms "mounted," "connected," and "connected" should be understood broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal connections between two components. The terms "parallel," "perpendicular," and "equal" encompass the described situations and situations similar to the described situations, provided that the range of the similar situations is within an acceptable deviation range, where the acceptable deviation range is determined by a person of ordinary skill in the art taking into account the measurement in question and the errors associated with the measurement of the specific quantity (i.e., the limitations of the measurement system). For example, "parallel" includes absolute parallelism and approximate parallelism, wherein the acceptable deviation range of approximate parallelism may be, for example, within 5°; "perpendicular" includes absolute perpendicularity and approximate perpendicularity, wherein the acceptable deviation range of approximate perpendicularity may also be, for example, within 5°. "Equal" includes absolute equality and approximate equality, wherein the acceptable deviation range of approximate equality may be, for example, that the difference between the two is less than or equal to 5% of either. For those skilled in the art, the specific meanings of the above terms in this application can be understood according to the specific circumstances.

[0017] In order to enable those skilled in the art to better understand the present application, the present application is further described in detail below with reference to the accompanying drawings and specific implementation methods.

[0018] Currently, high-speed signals are all transmitted in differential form. Differential signaling is a communication method that uses two signal transmission lines with opposite phases, namely differential signal line P and differential signal line N, to transmit the same signal. The transmitting end generates a pair of signals of equal magnitude and opposite polarity, which are respectively recorded as the positive and negative poles of the differential signal line. Differential signal lines have the advantages of strong anti-interference ability, low electromagnetic radiation, low radiation energy, low voltage swing and high energy efficiency, precise timing control, and resistance to power supply and ground noise. When designing differential signal lines, differential signal lines P and differential signal lines N must be strictly equal in length. Otherwise, phase offset will occur, which will increase signal jitter and convert common-mode noise into differential-mode noise.

[0019] To control the synchronous transmission of two differential signals from the transmitter to the receiver, existing solutions all achieve this by controlling the equal lengths of the differential signal lines P and N. This is generally achieved based on Cadence wiring software and setting constraint rules. The constraint conditions of the constraint rules can only be set to equal total lengths, that is, the total lengths of the differential signal lines P from the transmitter to the receiver and the differential signal lines N from the transmitter to the receiver are equal.

[0020] Figure 1 The following is a schematic diagram of the structure of differential signal lines in related art. The transmitter of the differential signal line is chip A, and the receiver of the differential signal line is chip B. Chip A's ball grid array (BGA) area is relatively narrow and is designed with a line width of 3.5 mils and a line spacing of 4 mils. The wiring is then routed using a normal design line width and line spacing, with a normal design line width of 5.0 mils and a line spacing of 6 mils. The connection between the thick line in the normal area and the thin line of 3.5 mils is connected with a thin line of 3.5 mils. The thick line of normal line width then passes through a via connecting two circuit board layers and connects to another circuit board layer. The other circuit board layer has a normal line width and is connected to chip B. Several 3W2S bumps are wound between the via and chip B to ensure that the length of differential signal line P and differential signal line N is controlled within 5 mils.

[0021] The 3W2S bump indicates that the straight line protruding from the bump (i.e., the portion parallel to the differential signal line P or differential signal line) is three times the line width W of the corresponding trace, or 3W. Its distance from the differential signal line N is twice the spacing S between differential signal lines P and N, or 2S. The bump trace is tilted upward at 45°. The 3W2S compensation method inserts a fixed value for the bump, making it difficult to achieve exactly the same length, resulting in compensation errors.

[0022] like Figure 2As shown, in the related art, the line width of the routing used at the connection between the 3.5mil thin line and the normal line width thick line is 3.5mil, and there is a certain spare area at the connection between it and the normal line width, where there is an impedance discontinuity problem.

[0023] Therefore, in the related art, there are at least the following disadvantages: The ultimate goal of making the differential signal line P and the differential signal line N equal in length is to ensure that the signals arrive at the receiving end at the same time, that is, at the same time. However, in actual software operation, isochronism is not easy to operate, so it is converted to equal length to control isochronism. The existing design and the existing software rule setting method only consider the overall equal length of the differential signal line P and the differential signal line N, ignoring the differences in the unit transmission delay of the line segments in different areas, and not considering the real design requirements, that is, the equal arrival of the PN signal. Although it achieves the equal length of the wiring, there are still differences in the delay of the PN signal. For example, the transmission delay of the line segments at different levels is different for the thin line of 3.5 mil and the thick line of normal line width. The simple design of the overall equal length of the routing will lead to high bit error rate, increased common mode noise, eye diagram collapse and other signal integrity issues.

[0024] When using the 3W2S design approach, the length of each bump is pre-set and fixed. This makes it difficult to achieve the ideal state of completely equal lengths for differential signal lines P and N during the routing process. Even if appropriate compensation measures are taken, there will inevitably be some difference in the lengths of the two differential signal lines after compensation. For example, the current equal length control requirement for differential signals is 5 mils, that is, the length difference between differential signal lines P and N should not exceed 5 mils. This can also increase the delay between the differential signals, which may cause signal integrity issues.

[0025] In addition, the relevant design cannot match the connection well at the junction of the 3.5mil thin line width and the normal line width, resulting in impedance discontinuity, which also affects the signal quality of high-speed signals.

[0026] In order to solve at least one disadvantage of the above technology, the embodiment of the present application provides a printed circuit board, such as Figure 3 As shown, at least two signal transmission lines are provided on the printed circuit board.

[0027] The signal transmission lines are generally arranged in pairs, for example, two, four, or six signal transmission lines are provided, and each pair of signal transmission lines is provided in a fixed distance. For example, there are two signal transmission lines, and the two signal transmission lines transmit high-speed signals between a receiving end and a transmitting end.

[0028] The signal transmission line includes several transmission line segments connected in sequence. Different transmission line segments of the same signal transmission line have different transmission delays per unit length. The transmission line segments of different signal transmission lines are arranged relative to each other and the transmission delays per unit length of the relative transmission line segments are the same.

[0029] In some embodiments, as Figure 3 As shown, the transmission line segments of the signal transmission line include a first transmission line segment 1 and a second transmission line segment 2 connected to each other, and the line width of the first transmission line segment 1 is different from the line width of the second transmission line segment 2.

[0030] Specifically, the first transmission line segments 1 of the two signal transmission lines are arranged opposite to each other and are located in the same area, and the second transmission line segments 2 of the two signal transmission lines are arranged opposite to each other and are located in the same area.

[0031] On printed circuit boards, the signal transmission delay per unit length is related to the equivalent dielectric constant, and different trace widths affect the trace's equivalent dielectric constant. Therefore, traces with different trace widths have different transmission delays per unit length. This means that even if two traces have the same length, their signal transmission delays will differ due to different trace widths.

[0032] The first transmission line segment 1 and the second transmission line segment 2 are located in different areas of the same layer of the printed circuit board (PCB). Due to their respective routing constraints, they have different line widths. For example, the first transmission line segment 1 is located in the BGA area of ​​a chip or other area with limited wiring space, requiring a smaller line width and line spacing, such as a line width of 3.5 mils and a line spacing of 4 mils. The second transmission line segment 2 is located in the normal routing area of ​​the PCB, with a line width of 5.0 mils and a line spacing of 6 mils. Due to their different line widths, the first and second transmission line segments 1 and 2 have different transmission delays per unit length, necessitating equalization of the lengths of the first and second transmission line segments 1 and 2.

[0033] Furthermore, if Figure 4 As shown, the printed circuit board includes a first wiring layer and a second wiring layer, the first transmission line segment 1 and the second transmission line segment 2 are both arranged on the first wiring layer, and the transmission line segments of the signal transmission line also include a third transmission line segment 4, which is arranged on the second wiring layer. The third transmission line segment 4 and the second transmission line segment 2 are connected through vias connecting the first wiring layer and the second wiring layer.

[0034] Specifically, the third transmission line segments 4 of the two signal transmission lines are arranged opposite to each other, and the line widths of the second transmission line segment 2 and the third transmission line segment 4 may be the same or different.

[0035] In printed circuit board (PCB) manufacturing, multiple wiring layers are used to increase wiring space and facilitate the design of complex signal transmission lines. Vias connect transmission line segments on different wiring layers, allowing for flexible adjustment of signal transmission paths to meet diverse circuit layouts and signal transmission requirements. Vias are lined with conductors such as copper to ensure smooth current flow through the vias, enabling efficient signal transmission between different wiring layers.

[0036] In printed circuit boards (PCBs), the equivalent dielectric constant of transmission lines is a key determinant of signal propagation speed, and its value is influenced by multiple factors, including material properties, physical structure, manufacturing process, and operating frequency. Different layers of a PCB correspond to different stacking structures, and different stacking structures correspond to different prepregs, resulting in different equivalent dielectric constants. Even with the same stacking structure, the type of prepreg used can vary due to differences in residual copper content and adhesive content on the PCB, leading to differences in dielectric constants. Furthermore, the use of different copper foil types at different layers and the varying manufacturing processes of different manufacturers can also affect the dielectric constant value. Therefore, even if the second transmission line segment 2 and the third transmission line segment 4 on different wiring layers have the same line width, they will have different transmission delays per unit length due to differences in the materials and stacking structures of the wiring layers. Therefore, in this embodiment of the present invention, the first transmission line segment 1, the second transmission line segment 2, and the third transmission line segment 4 are treated as equal lengths.

[0037] In some embodiments, as Figure 5 As shown, the printed circuit board includes a first wiring layer and a second wiring layer, and the transmission line segments of the signal transmission line include a fourth transmission line segment 7 and a fifth transmission line segment 8 that are connected to each other. The fourth transmission line segment 7 is arranged on the first wiring layer, and the fifth transmission line segment 8 is arranged on the second wiring layer. The fourth transmission line segment 7 and the fifth transmission line segment 8 are connected by vias connecting the first wiring layer and the second wiring layer.

[0038] Specifically, the line widths of the fourth transmission line segment 7 and the fifth transmission line segment 8 can be the same or different. When no specific width restrictions are required in either the first or second wiring layer, the line widths of the fourth and fifth transmission line segments 7 and 8 can both be 5.0 mils, with a line spacing of 6.0 mils. In this case, the signal transmission line can simply be divided into two segments: the fourth transmission line segment 7 and the fifth transmission line segment 8, each of which can be designed to be equal in length.

[0039] It should be understood that the division of signal transmission lines can be set according to actual conditions. For example, when there are several wiring layers, it is necessary to divide them into several types of transmission line segments accordingly. In the same wiring layer, when there are several traces of different thicknesses, they also need to be divided into several types of transmission line segments accordingly.

[0040] The two transmission line segments are a to-be-adjusted transmission line segment and a target transmission line segment, and the to-be-adjusted transmission line segment and the target transmission line segment each include a parallel segment, the length of the parallel segment of the to-be-adjusted transmission line segment is less than the length of the parallel segment of the target transmission line segment, and the to-be-adjusted transmission line segment further includes a plurality of compensation line segments 3, which are inserted between the parallel segments of the to-be-adjusted transmission line segment, so that the lengths of the two transmission line segments are the same.

[0041] Specifically, the two transmission line segments are each pair of transmission line segments in the signal transmission line, for example, the two first transmission line segments 1 in the signal transmission line are the two transmission line segments.

[0042] Taking the structure of the two first transmission line segments 1 as an example, the two first transmission line segments 1 are located in the BGA region of the chip, and due to space limitations, thin lines with a line width of 3.5 mil and a line spacing of 4 mil are required. Since the starting positions of the two signal transmission lines, i.e., the two first transmission line segments 1, in the BGA region are not on the same longitudinal axis, there is a difference in the lengths of the two first transmission line segments 1 in the BGA region. Therefore, the routing of the shorter transmission line segment in the 3.5 mil line width needs to be compensated. One of the two first signal transmission line segments, whose starting position is far from the end position, is taken as the target transmission line segment, and the other is taken as the to-be-adjusted transmission line segment.

[0043] The to-be-adjusted transmission line segment and the target transmission line segment each include a parallel segment, the line spacing of the parallel segment of the to-be-adjusted transmission line segment is equal to that of the target transmission line segment, and since the starting position of the target transmission line segment is far from the end position, the length of the parallel segment of the target transmission line segment is greater than that of the to-be-adjusted transmission line segment when the to-be-adjusted transmission line segment does not insert the compensation line segment 3.

[0044] The parallel segment is a relatively parallel segment part in the to-be-adjusted transmission line segment and the target transmission line segment. For the target transmission line segment, since the compensation line segment 3 does not need to be inserted, the entire target transmission line segment can be taken as a parallel segment. For the to-be-adjusted transmission line segment, when one compensation line segment 3 is inserted, the to-be-adjusted transmission line segment is divided into two parallel segments and the compensation line segment 3 connected between the two parallel segments.

[0045] The shape of the compensation line segment 3 is a convex bulge, and the shape of the convex bulge includes a trapezoidal shape, a triangular shape, a rectangular shape, a semicircular shape, etc. The length of the to-be-adjusted transmission line segment is increased by the winding setting of the convex bulge. When designing the to-be-adjusted transmission line segment, the number of inserted compensation line segments 3 is first determined, and then a corresponding number of compensation line segments 3 are added in the design process of the to-be-adjusted transmission line segment. Each compensation line segment 3 can be spaced or continuous. When spaced, the intervals can be equal or unequal.

[0046] After the compensation line segment 3 is inserted, the transmission line segment to be adjusted includes several parallel segments and compensation line segments 3 connected in sequence. Each time a compensation line segment 3 is inserted, the parallel segment is divided into two parts. Figure 3 、 Figure 4 and Figure 5 In the examples, only one compensation line segment 3 is inserted. In specific applications, the number of inserted compensation line segments 3 may be increased according to actual conditions.

[0047] For the other two opposite transmission line segments, such as the second transmission line segment 2 or the third transmission line segment 4, their structures and design methods are the same as those of the first transmission line segment 1, so that the two signal transmission lines are set to equal lengths in the second transmission line segment 2 and the third transmission line segment 4.

[0048] In related technologies, the signal transmission line adopts an overall equal-length structure, and the compensation line segments 3 are randomly distributed on one of the shorter signal transmission lines. This cannot ensure that the transmission line segments with different unit length transmission delays are of equal length, resulting in inconsistent signal delays.

[0049] The printed circuit board of the embodiment of the present invention performs winding compensation on transmission line segments with different line widths and different wiring layers in the signal transmission line, so that the transmission line segments with different unit length transmission delays in the signal transmission line are of equal length, thereby ensuring the consistency of the signal transmission delays of the two signal transmission lines. The signals transmitted by the two signal transmission lines arrive at the same time, and theoretically, the delays of the two signals can be completely equal, thereby eliminating timing offset, avoiding inter-symbol interference caused by phase offset, increasing eye diagram width, reducing bit error rate, and greatly improving the signal integrity design quality.

[0050] In addition, in theory, the delays of the two signals are completely equal, and their common-mode signals are zero, which can enhance the common-mode noise suppression capability, improve the signal anti-interference capability, and reduce electromagnetic interference (EMI) radiation.

[0051] In some embodiments, the shape parameters of the compensation line segment 3 meet preset constraints so that the length of the transmission line segment to be adjusted after inserting the compensation line segment 3 is equal to the length of the target transmission line segment, and the number of inserted compensation line segments 3 is minimized.

[0052] Specifically, the compensation line segment 3 includes several line segments connected in sequence, including but not limited to straight lines, curves, broken lines, etc.

[0053] The preset constraint condition is used to constrain the relationship between the length difference between the transmission line segment to be adjusted and the target transmission line segment and the shape parameters of the compensation line segment 3 when the compensation line segment 3 is not inserted. Length constraints or angle constraints of each line segment can also be further set.

[0054] The shape parameters of the compensation line segment 3 include the length of the line segments constituting the compensation line segment 3, the inclination angle, the overall height of the compensation line segment 3, etc. At least one shape parameter of the compensation line segment 3 can be dynamically set according to the preset constraints, so that different compensation values ​​are obtained after inserting the compensation line segment 3 under the premise of meeting the preset constraints, and the minimum number of inserted compensation line segments 3 under the condition of equal length is obtained, so that the length of the transmission line segment to be adjusted and the length of the target transmission line segment can be completely equal, and the number of inserted compensation line segments 3 is minimized, and the signal transmission quality is better.

[0055] In some embodiments, as Figure 6 As shown, the compensation line segment 3 includes a first connection line segment 31, an intermediate line segment 32, and a second connection line segment 33 connected in sequence. The two ends of the first connection line segment 31 are respectively connected to one end of the intermediate line segment 32 and the parallel segment on one side of the compensation line segment 3, and the two ends of the second connection line segment 33 are respectively connected to the other end of the intermediate line segment 32 and the parallel segment on the other side of the compensation line segment 3. The intermediate line segment 32 is parallel to the parallel segment of the target transmission line segment. The first connection line segment 31 and the second connection line segment 33 are symmetrically arranged with respect to the central axis of the intermediate line segment 32. The height of the intermediate line segment 32 and the inclination angle of the first connection line segment 31 meet preset constraints, so that the length of the transmission line segment to be adjusted after the compensation line segment 3 is inserted is equal to the length of the target transmission line segment, and the number of inserted compensation line segments 3 is minimized. The shape parameters of the compensation line segment 3 include the height of the intermediate line segment 32 and the inclination angle of the first connection line segment 31.

[0056] Specifically, the height of the middle line segment 32 is the distance between the middle line segment 32 and the transmission line segment to be adjusted.

[0057] The preset constraints are the constraints of the height of the intermediate segment 32 and the inclination angle of the first connecting segment 31, which are pre-set according to the design requirements of the compensation segment 3. By setting the preset constraints, the length of the transmission segment to be adjusted and the length of the target transmission segment can be completely equal.

[0058] The preset constraints determine the relationship between the height of the intermediate segment 32, the inclination angle of the first connecting segment 31, and the length difference. The length difference is the difference between the lengths of the transmission segment to be adjusted and the target transmission segment when the compensation segment 3 is not inserted. The length difference is calculated by comparing the lengths of two opposing transmission segments after designing each segment based on basic routing rules, such as line spacing and line width requirements.

[0059] In the embodiment of the present application, the parallel segment of the intermediate line segment 32 and the target transmission line segment are parallel, and the first connection line segment 31 and the second connection line segment 33 are symmetrically arranged relative to the central axis of the intermediate line segment 32, that is, the inclination angle of the second connection line segment 33 is the same as that of the first connection line segment 31, so that the compensated length is only related to the height of the intermediate line segment 32 and the inclination angle of the first connection line segment 31. By determining the height of the intermediate line segment 32 and the inclination angle of the first connection line segment 31 under the premise of meeting the preset constraint condition, different compensation values can be obtained, and the minimum number of inserted compensation line segments 3 under the equal length condition can be obtained, so that the length of the to-be-adjusted transmission line segment and the length of the target transmission line segment are completely equal in length, and the number of inserted compensation line segments 3 is minimized, and the signal transmission quality is better.

[0060] In some embodiments, the first connection line segment 31 and the second connection line segment 33 are both inclined towards the direction close to the intermediate line segment 32. For example, the to-be-compensated transmission line segment is located above the target transmission line segment, and the compensation line segment 3 protrudes upwards, that is, the first connection line segment 31 and the second connection line segment 33 are both inclined upwards towards the direction close to the intermediate line segment 32. At this time, the shape of the compensation line segment 3 is trapezoidal.

[0061] When the shape of the compensation line segment 3 is trapezoidal, the preset constraint condition includes:

[0062] In the formula, N represents the number of inserted compensation line segments 3, L1 represents the length of the first connection line segment 31, θ1 represents the inclination angle of the first connection line segment 31, and φ1 and φ2 respectively represent the lower boundary and the upper boundary of the preset angle, H represents the height constraint constant, ΔL represents the length difference between the to-be-adjusted transmission line segment and the target transmission line segment when the compensation line segment 3 is not inserted, H1 represents the height of the intermediate line segment 32, D represents the line distance of the to-be-adjusted transmission line segment and the target transmission line segment.

[0063] Specifically, the height of the intermediate line segment 32 and the inclination angle of the first connection line segment 31 in the inserted compensation line segment 3 need to meet the preset constraint condition, the size and shape of the compensation line segment 3 are determined through the preset constraint condition, and the length of the to-be-adjusted transmission line segment and the target transmission line segment are equal after the compensation line segment 3 is inserted.

[0064] By determining the height of the intermediate line segment 32 and the inclination angle of the first connecting line segment 31 based on preset constraints, and screening the height of the intermediate line segment 32 and the inclination angle of the first connecting line segment 31 corresponding to the minimum number of insertions on the premise that the preset constraints are met, the size and shape of the inserted compensation line segment 3 can be determined. This can achieve that the length of the transmission line segment to be adjusted is exactly the same as the length of the target transmission line segment, and the number of inserted compensation line segments 3 is minimized, thereby improving the signal transmission quality.

[0065] For any two opposite transmission line segments, the line width of the transmission line segment to be adjusted The line width of the target transmission line segment is the same as that of the target transmission line segment, for example, the line width of both is 3.5 mil.

[0066] The preset lower boundary of the inclination angle of the first connecting line segment 31 ranges from 38° to 42°, the preset upper boundary of the inclination angle of the first connecting line segment 31 ranges from 48° to 52°, and the height constraint constant ranges from 0.8 to 1.2.

[0067] For example, the preset lower limit of the inclination angle of the first connecting line segment 31 is =38°, the upper limit of the preset angle of the inclination angle of the first connecting line segment 31 Equal to 48°, height constraint constant Equal to 0.8; or, the preset angle lower boundary of the inclination angle of the first connecting line segment 31 =42°, the upper limit of the preset angle of the inclination angle of the first connecting line segment 31 Equal to 52°, the height constraint constant Equal to 1.2; or, the preset angle lower boundary of the inclination angle of the first connecting line segment 31 =40°, the upper limit of the preset angle of the inclination angle of the first connecting line segment 31 is Equal to 50°, height constraint constant Equal to 1.

[0068] Setting the inclination angle of the first connecting line segment 31 too large will affect the signal transmission quality, while setting the height constraint constant too large will increase the wiring space. By further limiting the value range of the inclination angle and the height constraint constant of the first connecting line segment 31, the design of the compensation line segment 3 is made more operational and accurate. Designing within this range can ensure the stable performance of the signal transmitted by the compensation line segment 3 and effectively compensate for the signal transmission delay difference.

[0069] Furthermore, the length of the middle line segment 32 ranges from 2 to 4 , is the line width of the transmission line segment to be adjusted.

[0070] For example, the length of the middle line segment 32 is 2 , 3 or 4 The length of the middle line segment 32 is set according to the corresponding line width. Designing the middle line segment 32 within this range can ensure the overall coordination between the compensation line segment 3 and the signal transmission line, and avoid the degradation of signal quality due to excessive length or too short length.

[0071] In some embodiments, as Figure 7 As shown, the first connecting line segment 31 includes a first chamfered line segment 311, a first main line segment 312, and a second chamfered line segment 313 connected in sequence. The second connecting line segment 33 includes a third chamfered line segment 331, a second main line segment 332, and a fourth chamfered line segment 333 connected in sequence. The two ends of the first chamfered line segment 311 are respectively connected to one end of the intermediate line segment 32 and the parallel segment on one side of the compensation line segment 3. The two ends of the fourth chamfered line segment 333 are respectively connected to the other end of the intermediate line segment 32 and the parallel segment on the other side of the compensation line segment 3. The intermediate line segment 32 is parallel to the parallel segment of the target transmission line segment. The first main line segment 312 and the second main line segment 332 are both perpendicular to the parallel segment of the target transmission line segment. The first connecting line segment 31 and the second connecting line segment 33 are symmetrically arranged with respect to the central axis of the intermediate line segment 32.

[0072] By connecting the line segments through the first chamfered line segment 311 , the second chamfered line segment 313 , the third chamfered line segment 331 and the fourth chamfered line segment 333 , a small angle between connected line segments and uneven line segment connections can be avoided, thereby improving signal transmission quality.

[0073] In some embodiments, the first chamfered line segment 311, the first main line segment 312, the second chamfered line segment 313, the intermediate line segment 32, the third chamfered line segment 331, the second main line segment 332, and the fourth chamfered line segment 333 are all straight line segments. Correspondingly, the preset constraints include:

[0074] Where, Indicates the number of inserted compensation segments 3, Indicates the length difference between the transmission line segment to be adjusted and the target transmission line segment when the compensation line segment 3 is not inserted. represents the height of the middle line segment 32, Indicates the line distance between the transmission line segment to be adjusted and the target transmission line segment, and Respectively represent the preset angle lower boundary and the preset angle upper boundary, represents the height constraint constant, represents the inclination angle of the first chamfered line segment 311, represents the inclination angle of the second chamfered line segment 313, represents the inclination angle of the third chamfered line segment 331, represents the inclination angle of the fourth chamfered line segment 333, represents the length of the projection of the first chamfered line segment 311 in the direction perpendicular to the middle line segment 32, represents the length of the projection of the second chamfered line segment 313 in the direction perpendicular to the middle line segment 32, represents the length of the projection of the third chamfered line segment 331 in the direction perpendicular to the middle line segment 32, represents the length of the projection of the fourth chamfered line segment 333 in the direction perpendicular to the middle line segment 32, represents the length of the first main body segment 312, represents the length of the second main body segment 332.

[0075] Specifically, the preset angle lower boundary Equal to 40°, preset angle upper boundary Equal to 50°, height constraint constant Equal to 1.

[0076] Preferably, the inclination angles of the first chamfered line segment 311 , the second chamfered line segment 313 , the third chamfered line segment 331 and the fourth chamfered line segment 333 are all 45°. When the inclination angle is 45°, the signal transmission quality is best.

[0077] Furthermore, to facilitate the solution, the lengths of the first chamfered line segment 311, the second chamfered line segment 313, the third chamfered line segment 331, and the fourth chamfered line segment 333 are set to be equal, and their inclination angles are set to be equal. For example, the lengths of the first chamfered line segment 311, the second chamfered line segment 313, the third chamfered line segment 331, and the fourth chamfered line segment 333 are all set to be 1.0 mil, and their inclination angles are all set to be 45°.

[0078] In an embodiment of the present invention, a first main line segment 312 is inserted into the first chamfered line segment 311 and the second chamfered line segment 313, and a second main line segment 332 is inserted into the third chamfered line segment 331 and the fourth chamfered line segment 333, and the first main line segment 312 and the second main line segment 332 are both perpendicular to the middle line segment 32. In this way, the added first main line segment 312 and the second main line segment 332 can directly compensate for the difference between the two transmission line segments. In addition, each chamfered line segment can also compensate for a certain difference. When the height of the middle line segment 32 is the same, the compensation line segment 3 can compensate for more differences, thereby reducing the number of inserted compensation line segments 3 and improving the signal transmission quality.

[0079] In some embodiments, as Figure 8As shown, the first main line segment 312 and the second main line segment 332 are both straight line segments, and the first chamfered line segment 311 , the second chamfered line segment 313 , the third chamfered line segment 331 and the fourth chamfered line segment 333 are all arc lines.

[0080] Specifically, the radii corresponding to the arc lines of the first chamfered line segment 311, the second chamfered line segment 313, the third chamfered line segment 331, and the fourth chamfered line segment 333 are all equal, and the angles corresponding to the arc lines of the first chamfered line segment 311, the second chamfered line segment 313, the third chamfered line segment 331, and the fourth chamfered line segment 333 are all 90°. Correspondingly, the preset constraints include:

[0081] Where, Indicates the number of inserted compensation segments 3, Indicates the length difference between the transmission line segment to be adjusted and the target transmission line segment when the compensation line segment 3 is not inserted. represents the height of the middle line segment 32, Indicates the line distance between the transmission line segment to be adjusted and the target transmission line segment, represents the height constraint constant, represents the inclination angle of the first chamfered line segment 311, represents the radius of the arc lines corresponding to the first chamfered line segment 311, the second chamfered line segment 313, the third chamfered line segment 331 and the fourth chamfered line segment 333, represents the length of the first main body segment 312, represents the length of the second main body segment 332.

[0082] By replacing the chamfered line segments with arcs, a new compensation line segment 3 structure can be provided, enriching the implementation of wiring compensation. Furthermore, by setting the angles corresponding to the four arcs to 90°, the sum of the lengths of the four chamfered line segments equals the circumference of the circle, facilitating the setting and calculation of preset constraints.

[0083] In some embodiments, the compensation line segment 3 includes a semicircular arc, with both ends of the semicircular arc connected to the parallel segments on both sides respectively. The radius of the semicircular arc satisfies preset constraints, such that the length of the transmission line segment to be adjusted after the compensation line segment 3 is inserted is equal to the length of the target transmission line segment, and the number of inserted compensation line segments 3 is minimized. The shape parameter of the compensation line segment 3 includes the radius of the semicircular arc. The preset constraints include:

[0084] Where, Indicates the number of inserted compensation segments 3, represents the radius of the semicircle, Indicates the length difference between the transmission line segment to be adjusted and the target transmission line segment when the compensation line segment 3 is not inserted. represents the height constraint constant, Indicates the line distance between the transmission line segment to be adjusted and the target transmission line segment.

[0085] Specifically, if Figure 9 As shown, the compensation line segment 3 of the semicircular arc structure adopts a curved design, which can be applied to scenarios where a straight line bulge cannot be added, thereby improving the application range of the printed circuit board.

[0086] In some embodiments, the compensation line segment 3 includes a first connecting line segment 31 and a second connecting line segment 33. One end of the first connecting line segment 31 is connected to the parallel segment on one side of the compensation line segment 3. The other end of the first connecting line segment 31 is connected to one end of the second connecting line segment 33 to form a wedge-shaped protrusion. The other end of the second connecting line segment 33 is connected to the parallel segment on the other side of the compensation line segment 3. The height of the wedge-shaped protrusion, the inclination angle of the first connecting line segment 31, and the inclination angle of the second connecting line segment 33 satisfy preset constraints, so that the length of the transmission line segment to be adjusted after the compensation line segment 3 is inserted is equal to the length of the target transmission line segment, and the number of inserted compensation line segments 3 is minimized. The shape parameters of the compensation line segment 3 include the height of the wedge-shaped protrusion, the inclination angle of the first connecting line segment 31, and the inclination angle of the second connecting line segment 33. The preset constraints include:

[0087] Where, Indicates the number of inserted compensation segments 3, Indicates the length difference between the transmission line segment to be adjusted and the target transmission line segment when the compensation line segment 3 is not inserted. represents the height of the wedge-shaped protrusion, Indicates the line distance between the transmission line segment to be adjusted and the target transmission line segment, represents the inclination angle of the first connecting line segment 31, represents the inclination angle of the second connecting line segment 33 .

[0088] Specifically, if Figure 10 As shown, the height of the wedge-shaped protrusion The inclination angle of the first connecting line segment 31 is and the inclination angle of the second connecting line segment 33 The sizes can be equal or unequal.

[0089] The number of segments required for the design of the compensation segment 3 of the wedge-shaped protrusion structure is small, which increases the flexibility of the design. By meeting the preset constraints, the number of compensation segments 3 can be reduced while ensuring the compensation effect, thereby improving the compensation efficiency.

[0090] In some embodiments, the wedge-shaped protrusions may be provided in a plurality of continuous portions to form a sawtooth structure.

[0091] It should be understood that in other embodiments, the additional compensating segment 3 may also have a downwardly concave structure. For example, the additional compensating segment 3 may be disposed on the transmission segment to be adjusted. The compensating segment 3 may be trapezoidal, rectangular, wedge-shaped, semicircular, etc., and the compensating segment 3 may be concave toward the target transmission segment.

[0092] When the compensation line segment 3 is recessed downward, the wiring space can be reduced, but the signal transmission quality will be affected.

[0093] In some embodiments, the transmission line segment of the signal transmission line includes a first transmission line segment 1 and a second transmission line segment 2 connected to each other, the line width of the first transmission line segment 1 is smaller than the line width of the second transmission line segment 2, the first transmission line segment 1 and the second transmission line segment 2 are connected by a gradient line segment 9, the first connection end of the gradient line segment 9 is connected to the first transmission line segment 1, the second connection end of the gradient line segment 9 is connected to the second transmission line, and the line width of the gradient line segment 9 gradually increases from the first connection end to the second connection end.

[0094] Specifically, the first transmission line segment 1 and the second transmission line segment 2 are located in different areas of the same layer of the printed circuit board. Due to their respective routing constraints, they have different line widths. For example, the first transmission line segment 1 is located in the BGA area of ​​the chip and has a line width of 3.5 mils, while the second transmission line segment 2 is located in the normal routing area of ​​the printed circuit board and has a line width of 5.0 mils.

[0095] like Figure 11 As shown, the distance between the end point of the first transmission line segment 1 and the starting point of the second transmission line segment 2 is about 3 mil. After the first transmission line segment 1 and the second transmission line segment 2 are set to be equal in length, the first transmission line segment 1 and the second transmission line segment 2 of the signal transmission line are connected by a gradient line segment 9. The gradient line segments 9 of the two signal transmission lines are symmetrical with respect to the center lines of the two signal transmission lines and have the same length to ensure the same signal transmission delay.

[0096] The line width of the gradient line segment 9 gradually increases from the first connection end to the second connection end, which can reduce the impedance mutation degree between two transmission lines with different line widths.

[0097] The design of the gradient line segment 9 makes the line width change smoother. The gradient line segment 9 is used to connect the first transmission line segment 1 and the second transmission line segment 2 with two different line widths, avoiding the discontinuity of single-point impedance caused by traditional wiring methods, so that the impedance can be smoothly transitioned, greatly improving signal integrity and enhancing signal design quality.

[0098] Further, the width of the first connecting end is the same as the line width of the first transmission line segment 1, and the connecting end face of the first connecting end and the first transmission line segment 1 coincide, and the width of the second connecting end is the same as the line width of the second transmission line segment 2, and the connecting end face of the second connecting end and the second transmission line segment 2 coincide.

[0099] In this way, the width of the two connecting ends of the gradual change line segment 9 is the same as the first transmission line segment 1 and the second transmission line segment 2 respectively, which ensures that the connection of the gradual change line segment 9 with the first transmission line segment 1 and the second transmission line segment 2 is smooth, further reduces the signal reflection and impedance mismatch problem, and improves the quality and reliability of signal transmission.

[0100] In some embodiments, the signal transmission line adopts a differential signal line. The differential signal line is arranged in pairs, and a pair of differential signal lines, i.e., a differential signal line P and a differential signal line N, are used to transmit two signals of equal size and opposite polarity respectively. When designing the differential signal line, the differential signal line P and the differential signal line N need to be strictly equal in length.

[0101] Further, the printed circuit board further comprises a first electronic element 5 and a second electronic element 6, and the two ends of the differential signal line are connected to the first electronic element 5 and the second electronic element 6 respectively.

[0102] Specifically, the first electronic element 5 and the second electronic element 6 are respectively the sending end and the receiving end of the differential signal, and the first electronic element 5 and the second electronic element 6 can be various types of chips such as Field Programmable Gate Array (FPGA) and Microcontroller Unit (MCU).

[0103] For example, the first electronic element 5 is a chip A, and the second electronic element 6 is a chip B. The chip A and the chip B can be different types of chips or the same type of chips. At least one pair of differential signal lines is connected between the chip A and the chip B, and differential signals are transmitted through the differential signal lines. Differential signal transmission is based on two signals of equal size and opposite polarity to transmit information. When the chip A is the sending end, it will generate two complementary signals at the same time and transmit them through the differential signal line P and the differential signal line N respectively. Due to the characteristics of the two signals, they will be affected by the same external interference during transmission. When reaching the receiving end chip B, the chip B will perform differential operation, i.e., subtraction operation, on the two signals. In this way, the same part of external interference introduced in the two signals will be eliminated, thereby greatly improving the anti-interference ability of the signal.

[0104] Differential signal lines are widely used in server boards. In the design of server boards, in order to fully utilize the advantages of differential signal lines, it is necessary to ensure that the differential signal lines P and N are strictly equal in length. Therefore, the printed circuit board of the embodiment of the present invention can be used in servers to improve the overall reliability and stability of the server boards.

[0105] An embodiment of the present invention further provides a server, comprising the printed circuit board as described in any of the above embodiments.

[0106] The embodiment of the present invention further provides a wiring compensation design method, which is applied to designing the printed circuit board in any of the above embodiments, such as Figure 12 As shown, the method includes: Step S101: dividing the signal transmission line into a plurality of sequentially connected transmission line segments based on preset delay characteristics of the signal transmission line in different areas of the printed circuit board, wherein different transmission line segments of the same signal transmission line have different transmission delays per unit length, and transmission line segments of different signal transmission lines are arranged relative to each other and have the same transmission delay per unit length; Step S102 : performing wiring compensation on two opposite transmission line segments so that the lengths of any two opposite transmission line segments are equal.

[0107] In some embodiments, the preset delay characteristic includes a line width. In step S101, the signal transmission line is divided into a plurality of sequentially connected transmission line segments according to the preset delay characteristics of the signal transmission line in different areas of the printed circuit board, including: Step S1011 : dividing the signal transmission line on the first layer of the printed circuit board into a first transmission line segment 1 and a second transmission line segment 2 connected to each other according to different line widths, wherein the line widths of the first transmission line segment 1 and the second transmission line segment 2 are different.

[0108] In some embodiments, the preset delay characteristics further include a wiring position, after dividing the signal transmission line on the first layer of the printed circuit board into a first transmission line segment 1 and a second transmission line segment 2 connected to each other according to different line widths, including: Step S1012: dividing the signal transmission line located on the second layer of the printed circuit board into third transmission line segments 4 according to the wiring positions, wherein the second transmission line segment 2 and the third transmission line segment 4 are connected through vias.

[0109] In some embodiments, in step S102 , wiring compensation is performed on two opposite transmission line segments to make the lengths of any two opposite transmission line segments equal, including.

[0110] Step S1021, obtaining the length difference between the transmission line segment to be adjusted and the target transmission line segment when the compensation line segment 3 is not inserted; Step S1022, establishing a preset constraint condition based on the length difference; Step S1023, solving according to the preset constraint conditions to obtain the minimum number of compensation line segments 3 that meets the preset constraint conditions, and using the minimum number of compensation line segments 3 as the number of inserted compensation line segments 3; Step S1024 : determining the shape parameters of the compensation line segment 3 according to the number of inserted compensation line segments 3 .

[0111] In some embodiments, the compensation line segment 3 includes a first connection line segment 31, an intermediate line segment 32, and a second connection line segment 33 connected in sequence. The two ends of the first connection line segment 31 are respectively connected to one end of the intermediate line segment 32 and the parallel segment on one side of the compensation line segment 3, and the two ends of the second connection line segment 33 are respectively connected to the other end of the intermediate line segment 32 and the parallel segment on the other side of the compensation line segment 3; the intermediate line segment 32 is parallel to the parallel segment of the target transmission line segment, and the first connection line segment 31 and the second connection line segment 33 are symmetrically arranged with respect to the central axis of the intermediate line segment 32. The first connection line segment 31 and the second connection line segment 33 are both inclined in the direction close to the intermediate line segment 32, that is, the shape of the compensation line segment 3 is trapezoidal.

[0112] When the shape of the compensation line segment 3 is a trapezoid, the shape parameters of the compensation line segment 3 include the height of the middle line segment 32 and the inclination angle of the first connecting line segment 31. The preset constraint conditions include:

[0113] Where, Indicates the number of inserted compensation segments 3, represents the length of the first connecting line segment 31, represents the inclination angle of the first connecting line segment 31, and Respectively represent the preset angle lower boundary and the preset angle upper boundary, represents the height constraint constant, It indicates the length difference between the transmission line segment to be adjusted and the target transmission line segment when the compensation line segment 3 is not inserted. represents the height of the middle line segment 32, Indicates the line distance between the transmission line segment to be adjusted and the target transmission line segment.

[0114] Specifically, the preset angle lower boundary of the inclination angle of the first connecting line segment 31 ranges from 38° to 42°, the preset angle upper boundary of the inclination angle of the first connecting line segment 31 ranges from 48° to 52°, the height constraint constant ranges from 0.8 to 1.2, and the length of the middle line segment 32 ranges from 2 to 4 .

[0115] In some embodiments, the first connecting line segment 31 includes a first chamfered line segment 311, a first main line segment 312, and a second chamfered line segment 313 connected in sequence. The second connecting line segment 33 includes a third chamfered line segment 331, a second main line segment 332, and a fourth chamfered line segment 333 connected in sequence. The two ends of the first chamfered line segment 311 are respectively connected to one end of the intermediate line segment 32 and the parallel segment on one side of the compensation line segment 3. The two ends of the fourth chamfered line segment 333 are respectively connected to the other end of the intermediate line segment 32 and the parallel segment on the other side of the compensation line segment 3. The intermediate line segment 32 is parallel to the parallel segment of the target transmission line segment. The first main line segment 312 and the second main line segment 332 are both perpendicular to the parallel segment of the target transmission line segment. The first connecting line segment 31 and the second connecting line segment 33 are symmetrically arranged relative to the central axis of the intermediate line segment 32.

[0116] By connecting the line segments through the first chamfered line segment 311 , the second chamfered line segment 313 , the third chamfered line segment 331 and the fourth chamfered line segment 333 , a small angle between connected line segments and uneven line segment connections can be avoided, thereby improving signal transmission quality.

[0117] In some embodiments, the first chamfered line segment 311, the first main line segment 312, the second chamfered line segment 313, the intermediate line segment 32, the third chamfered line segment 331, the second main line segment 332, and the fourth chamfered line segment 333 are all straight line segments. Correspondingly, the preset constraints include:

[0118] Where, Indicates the number of inserted compensation segments 3, It indicates the length difference between the transmission line segment to be adjusted and the target transmission line segment when the compensation line segment 3 is not inserted. represents the height of the middle line segment 32, Indicates the line distance between the transmission line segment to be adjusted and the target transmission line segment, and Respectively represent the preset angle lower boundary and the preset angle upper boundary, represents the height constraint constant, represents the inclination angle of the first chamfered line segment 311, represents the inclination angle of the second chamfered line segment 313, represents the inclination angle of the third chamfered line segment 331, represents the inclination angle of the fourth chamfered line segment 333, represents the length of the projection of the first chamfered line segment 311 in the direction perpendicular to the middle line segment 32, represents the length of the projection of the second chamfered line segment 313 in the direction perpendicular to the middle line segment 32, represents the length of the projection of the third chamfered line segment 331 in the direction perpendicular to the middle line segment 32, represents the length of the projection of the fourth chamfered line segment 333 in the direction perpendicular to the middle line segment 32, represents the length of the first main body segment 312, represents the length of the second main body segment 332.

[0119] In an embodiment of the present invention, a first main line segment 312 is inserted into the first chamfered line segment 311 and the second chamfered line segment 313, and a second main line segment 332 is inserted into the third chamfered line segment 331 and the fourth chamfered line segment 333, and the first main line segment 312 and the second main line segment 332 are both perpendicular to the middle line segment 32. In this way, the added first main line segment 312 and the second main line segment 332 can directly compensate for the difference between the two transmission line segments. In addition, each chamfered line segment can also compensate for a certain difference. When the height of the middle line segment 32 is the same, the compensation line segment 3 can compensate for more differences, thereby reducing the number of inserted compensation line segments 3 and improving the signal transmission quality.

[0120] In some embodiments, the first main line segment 312 and the second main line segment 332 are both straight line segments, and the first chamfered line segment 311 , the second chamfered line segment 313 , the third chamfered line segment 331 and the fourth chamfered line segment 333 are all arc lines.

[0121] Specifically, the radii corresponding to the arc lines of the first chamfered line segment 311, the second chamfered line segment 313, the third chamfered line segment 331, and the fourth chamfered line segment 333 are all equal, and the angles corresponding to the arc lines of the first chamfered line segment 311, the second chamfered line segment 313, the third chamfered line segment 331, and the fourth chamfered line segment 333 are all 90°. Correspondingly, the preset constraints include:

[0122] Where, Indicates the number of inserted compensation segments 3, It indicates the length difference between the transmission line segment to be adjusted and the target transmission line segment when the compensation line segment 3 is not inserted. represents the height of the middle line segment 32, Indicates the line distance between the transmission line segment to be adjusted and the target transmission line segment, represents the height constraint constant, represents the inclination angle of the first chamfered line segment 311, represents the radius of the arc lines corresponding to the first chamfered line segment 311, the second chamfered line segment 313, the third chamfered line segment 331 and the fourth chamfered line segment 333, represents the length of the first main body segment 312, represents the length of the second main body segment 332.

[0123] By replacing the chamfered line segments with arcs, a new compensation line segment 3 structure can be provided, enriching the implementation of wiring compensation. Furthermore, by setting the angles corresponding to the four arcs to 90°, the sum of the lengths of the four chamfered line segments equals the circumference of the circle, facilitating the setting and calculation of preset constraints.

[0124] In some embodiments, the compensation line segment 3 includes a semicircular arc, with both ends of the semicircular arc connected to the parallel segments on both sides, and the radius of the semicircular arc satisfies preset constraints, such that the length of the transmission line segment to be adjusted after inserting the compensation line segment 3 is equal to the length of the target transmission line segment, and the number of inserted compensation line segments 3 is minimized. The preset constraints include:

[0125] Where, Indicates the number of inserted compensation segments 3, represents the radius of the semicircle, It indicates the length difference between the transmission line segment to be adjusted and the target transmission line segment when the compensation line segment 3 is not inserted. represents the height constraint constant, Indicates the line distance between the transmission line segment to be adjusted and the target transmission line segment.

[0126] Specifically, the compensation line segment 3 of the semicircular arc structure adopts a curved design, which can be applied to scenarios where a straight line bulge cannot be added, thereby improving the application range of the printed circuit board.

[0127] In some embodiments, the compensation line segment 3 includes a first connecting line segment 31 and a second connecting line segment 33. One end of the first connecting line segment 31 is connected to the parallel segment on one side of the compensation line segment 3. The other end of the first connecting line segment 31 is connected to one end of the second connecting line segment 33 to form a wedge-shaped protrusion. The other end of the second connecting line segment 33 is connected to the parallel segment on the other side of the compensation line segment 3. The height of the wedge-shaped protrusion, the inclination angle of the first connecting segment 31, and the inclination angle of the second connecting segment 33 satisfy preset constraints so that the length of the transmission segment to be adjusted after the compensation segment 3 is inserted is equal to the length of the target transmission segment, and the number of inserted compensation segments 3 is minimized. The preset constraints include:

[0128] Where, Indicates the number of inserted compensation segments 3, It indicates the length difference between the transmission line segment to be adjusted and the target transmission line segment when the compensation line segment 3 is not inserted. represents the height of the wedge-shaped protrusion, Indicates the line distance between the transmission line segment to be adjusted and the target transmission line segment, represents the inclination angle of the first connecting line segment 31, represents the inclination angle of the second connecting line segment 33 .

[0129] Specifically, the height of the wedge-shaped protrusion The inclination angle of the first connecting line segment 31 is and the inclination angle of the second connecting line segment 33 The sizes can be equal or unequal.

[0130] The number of segments required for the design of the compensation segment 3 of the wedge-shaped protrusion structure is small, which increases the flexibility of the design. By meeting the preset constraints, the number of compensation segments 3 can be reduced while ensuring the compensation effect, thereby improving the compensation efficiency.

[0131] It should be understood that in other embodiments, the added compensation line segment 3 may also adopt a downwardly protruding structure.

[0132] The wiring compensation design method according to the embodiment of the present invention is described below with reference to a specific example.

[0133] The printed circuit board includes a first wiring layer and a second wiring layer. Each signal transmission line includes a first transmission line segment 1, a second transmission line segment 2 and a third transmission line segment 4. The first transmission line segment 1 and the second transmission line segment 2 are both arranged on the first wiring layer, and the third transmission line segment 4 is arranged on the second wiring layer. The third transmission line segment 4 and the second transmission line segment 2 are connected by a via connecting the first wiring layer and the second wiring layer.

[0134] The first transmission line segments 1 of the two signal transmission lines are arranged opposite to each other, serving as the transmission line segment to be adjusted and the target transmission line segment respectively. The shape of the compensation line segment 3 is trapezoidal. When the compensation line segment 3 is not inserted, the length of the transmission line segment to be adjusted is less than the length of the target transmission line segment, and the length difference is Equal to 20mil.

[0135] First, the first transmission line segment 1 of the two signal transmission lines is wired for compensation. The line width of the first transmission line segment 1 of the two signal transmission lines is 3.5mil, line spacing 4mil, setting the preset angle lower boundary of the inclination angle of the first connecting line segment 31 = 40°, the upper limit of the inclination angle of the first connecting line segment 31 Equal to 50°, height constraint constant is equal to 1, and the length of the middle line segment 32 ranges from 3 , then the preset constraints are:

[0136] Set the solution precision to one decimal place.

[0137] Calculated according to the preset constraints:

[0138] To minimize , we need to maximize the denominator ,because and , so take The maximum value of , .therefore, The supremum is 4×0.4663=1.8652, The infimum of is about 5.362, because is an integer, so , proven when =5, the above preset constraint condition cannot be satisfied. Therefore, the minimum number of compensation line segments 3 that satisfies the preset constraint condition is 6.

[0139] Further, =6Substitute the above preset constraints and solve the calculation to get =6 corresponds to the maximum And the corresponding tilt angle .

[0140] when =6, we have:

[0141] because ,have:

[0142] The solution is .

[0143] Because tan22.5°≈0.4142<0.416675, tan23°≈0.4245>0.416675, by difference, ,Right now ,exist hour, Get the maximum value, which is 4.0mil.

[0144] Therefore, when designing the first transmission line segment 1, the number of inserted compensation segments 3 is set to 6, and the tilt angle is Set to , the height of the middle line segment 32 Set it to 4.0mil and perform routing accordingly to ensure that the transmission line segment to be adjusted and the target line segment are exactly the same length, and the number of inserted compensation line segments 3 is minimized.

[0145] After compensating the first transmission line segment 1, a normal routing with a 5-mil line width and a 6-mil line spacing is drawn, starting from the center line of the 3.5-mil differential line approximately 2 mils from the end point of the 3.5-mil line width. This is the second transmission line segment 2. The same routing compensation is performed on the second transmission line segment 2.

[0146] A tapered line segment 9 is provided between the first transmission line segment 1 and the second transmission line segment 2 of the same signal transmission line. The first connection end of the tapered line segment 9 is connected to the first transmission line segment 1, and the second connection end of the tapered line segment 9 is connected to the second transmission line. The line width of the tapered line segment 9 gradually increases from the first connection end to the second connection end. Furthermore, the width of the first connection end is the same as the line width of the first transmission line segment 1, and the connection end faces of the first connection end and the first transmission line segment 1 overlap. The width of the second connection end is the same as the line width of the second transmission line segment 2, and the connection end faces of the second connection end and the second transmission line segment 2 overlap. This arrangement ensures smooth impedance changes at the connection, avoids single-point impedance discontinuity, and thus improves signal quality.

[0147] Furthermore, the same method can be used to perform routing compensation on the third transmission line segment 4 on the second wiring layer. This completes the routing of the signal transmission line from the transmitter to the receiver. Because the two signal transmission lines on different layers have different line widths and are exactly the same length, theoretically, the signal transmission delays along the two lines are identical, and both signals arrive at the receiver simultaneously, significantly improving the signal integrity design quality.

[0148] When the compensation line segment 3 is of other shapes, a solution can also be performed according to corresponding preset constraints to obtain the corresponding shape parameters of the compensation line segment 3.

[0149] The wiring compensation design method of the embodiment of the present invention ensures the consistency of the signal transmission delay of the two signal transmission lines by setting the transmission line segments with different unit length transmission delays in the two signal transmission lines to be equal in length, and adopts a design of equal length segments of the signal transmission lines in different areas. The signals transmitted by the two signal transmission lines arrive at the same time, thereby greatly improving the signal integrity design quality.

[0150] The shape parameters of the compensation line segment 3 are constrained by preset constraints and dynamically solved to meet the equal-length wiring requirements. In addition, the number of inserted compensation line segments 3 is small. Compared with the traditional solution in which each compensation line segment 3 compensates for a fixed length, the embodiment of the present invention can improve the compensation accuracy and ensure that each transmission line segment is strictly equal in length.

[0151] For the first connecting line segment 31 and the second connecting line segment 33 of different thicknesses, there are impedance discontinuities. The embodiment of the present invention connects them through the gradient line segment 9, so that the impedance at the connection changes smoothly, avoiding single-point impedance discontinuity, thereby improving signal quality.

[0152] Through the description of the above implementation methods, those skilled in the art can clearly understand that the method according to the above embodiment can be implemented by means of software plus the necessary general hardware platform, and of course it can also be implemented by hardware, but in many cases the former is a better implementation method.

[0153] The embodiment of the present application also provides a wiring compensation design device, which is used to design any of the above-mentioned printed circuit boards, such as Figure 13 As shown, the device includes: The transmission line segmentation module 101 is configured to divide the signal transmission line into a plurality of sequentially connected transmission line segments according to preset delay characteristics of the signal transmission line in different areas of the printed circuit board, wherein different transmission line segments of the same signal transmission line have different transmission delays per unit length, and transmission line segments of different signal transmission lines are arranged relative to each other and have the same transmission delay per unit length; The segment compensation module 102 is used to perform wiring compensation on two opposite transmission line segments so that the lengths of any two opposite transmission line segments are equal.

[0154] In some embodiments, the preset delay characteristic includes line width, and the transmission line segmentation module includes: The line width division module is used to divide the signal transmission line on the first layer of the printed circuit board into a first transmission line segment 1 and a second transmission line segment 2 connected to each other according to the different line widths. The line widths of the first transmission line segment 1 and the second transmission line segment 2 are different.

[0155] In some embodiments, the preset delay characteristic further includes a wiring location, and the transmission line segmentation module further includes: The position division module is used to divide the signal transmission line located on the second layer of the printed circuit board into a third transmission line segment 4 according to the wiring position, wherein the second transmission line segment 2 and the third transmission line segment 4 are connected through vias.

[0156] In some embodiments, the segmented compensation module includes.

[0157] An interpolation acquisition module, used to obtain the length difference between the transmission line segment to be adjusted and the target transmission line segment when the compensation line segment 3 is not inserted; A constraint condition establishment module is used to establish a preset constraint condition based on the length difference; A parameter solving module is used to solve according to preset constraints, obtain the minimum number of compensation line segments 3 that meets the preset constraints, and use the minimum number of compensation line segments 3 as the number of inserted compensation line segments 3; The line segment insertion module is used to determine the shape parameters of the compensation line segment 3 according to the number of inserted compensation line segments 3.

[0158] For the description of the features in the embodiment corresponding to the wiring compensation design device, reference can be made to the relevant description of the embodiment corresponding to the wiring compensation design method, which will not be repeated here.

[0159] The embodiment of the present application also provides an electronic device, such as Figure 14 As shown, it includes a memory 10 and a processor 20. The memory 10 stores a computer program, and the processor 20 is configured to run the computer program to execute the steps in any of the above wiring compensation design method embodiments.

[0160] An embodiment of the present application further provides a computer-readable storage medium, in which a computer program is stored. The computer program is configured to execute the steps of any of the above-mentioned wiring compensation design method embodiments when running.

[0161] In an exemplary embodiment, the computer-readable storage medium may include, but is not limited to, various media that can store computer programs, such as a USB flash drive, a read-only memory (ROM), a random access memory (RAM), a mobile hard disk, a magnetic disk, or an optical disk.

[0162] An embodiment of the present application further provides a computer program product, which includes a computer program. When the computer program is executed by a processor, the steps of any of the above wiring compensation design method embodiments are implemented.

[0163] An embodiment of the present application also provides another computer program product, including a non-volatile computer-readable storage medium, which stores a computer program. When the computer program is executed by a processor, it implements the steps of any of the above-mentioned wiring compensation design method embodiments.

[0164] Those skilled in the art will further realize that the mere conception of the examples described herein is sufficient to enable practitioners to practice the examples as further described below. Therefore, numberous variations and modifications can be made to the examples described and illustrated herein without departing from the scope of the application. Accordingly, all such variations and modifications are intended to be included within the scope of the application as defined in the appended claims, along with all equivalents thereof.

[0165] The above provides a printed circuit board, a server, a wiring compensation method, a device, equipment and a medium. The principles and implementation manners of the application are described by using specific examples. The above description of the examples is only applicable to help understand the method and the core idea thereof. It should be pointed out that, for those skilled in the art, some improvements and modifications can be made to the application without departing from the principles of the application. These improvements and modifications also fall within the protection scope of the claims of the application.

Claims

1. A printed circuit board, characterized in that: The printed circuit board is provided with at least two signal transmission lines; The signal transmission line includes a plurality of sequentially connected transmission line segments, different transmission line segments of the same signal transmission line have different transmission delays per unit length, and the transmission line segments of different signal transmission lines are arranged opposite to each other and have the same transmission delay per unit length; Any two opposing transmission line segments are respectively a transmission line segment to be adjusted and a target transmission line segment. Both the transmission line segment to be adjusted and the target transmission line segment include parallel segments. The length of the parallel segments of the transmission line segment to be adjusted is less than the length of the parallel segments of the target transmission line segment. The transmission line segment to be adjusted further includes a plurality of compensation segments. The compensation segments are inserted between the parallel segments of the transmission line segment to be adjusted, so that the lengths of any two opposing transmission line segments are the same.

2. The printed circuit board according to claim 1, wherein: The transmission line segment of the signal transmission line includes a first transmission line segment and a second transmission line segment connected to each other, and a line width of the first transmission line segment is different from a line width of the second transmission line segment.

3. The printed circuit board according to claim 2, wherein: The printed circuit board includes a first wiring layer and a second wiring layer, the first transmission line segment and the second transmission line segment are both arranged on the first wiring layer, the transmission line segment of the signal transmission line also includes a third transmission line segment, the third transmission line segment is arranged on the second wiring layer, and the third transmission line segment and the second transmission line segment are connected through a via connecting the first wiring layer and the second wiring layer.

4. The printed circuit board according to claim 1, wherein: The printed circuit board includes a first wiring layer and a second wiring layer, and the transmission line segment of the signal transmission line includes a fourth transmission line segment and a fifth transmission line segment connected to each other, the fourth transmission line segment is arranged on the first wiring layer, and the fifth transmission line segment is arranged on the second wiring layer, and the fourth transmission line segment and the fifth transmission line segment are connected through a via connecting the first wiring layer and the second wiring layer.

5. The printed circuit board according to claim 1, wherein: The shape parameters of the compensation line segment meet preset constraints, so that the length of the transmission line segment to be adjusted is equal to the length of the target transmission line segment after the compensation line segment is inserted, and the number of the inserted compensation line segments is minimized.

6. The printed circuit board according to claim 5, characterized in that The compensation line segment includes a first connection line segment, an intermediate line segment, and a second connection line segment connected in sequence, wherein two ends of the first connection line segment are respectively connected to one end of the intermediate line segment and a parallel segment on one side of the compensation line segment, and two ends of the second connection line segment are respectively connected to the other end of the intermediate line segment and the parallel segment on the other side of the compensation line segment; The intermediate line segment is parallel to the parallel segment of the target transmission line segment, the first connecting line segment and the second connecting line segment are symmetrically arranged relative to the central axis of the intermediate line segment, and the values ​​of the height of the intermediate line segment and the inclination angle of the first connecting line segment satisfy preset constraints, so that after the compensation line segment is inserted, the length of the transmission line segment to be adjusted is equal to the length of the target transmission line segment, and the number of inserted compensation line segments is minimized. The shape parameters of the compensation line segment include the height of the intermediate line segment and the inclination angle of the first connecting line segment.

7. The printed circuit board according to claim 6, characterized in that The first connecting line segment and the second connecting line segment are both inclined toward the direction close to the middle line segment; The preset constraints include: Where, represents the number of the inserted compensation segments, represents the length of the first connecting line segment, represents the inclination angle of the first connecting line segment, and Respectively represent the preset angle lower boundary and the preset angle upper boundary, represents the height constraint constant, represents the length difference between the transmission line segment to be adjusted and the target transmission line segment when the compensation line segment is not inserted, represents the height of the middle line segment, Indicates the line distance between the transmission line segment to be adjusted and the target transmission line segment.

8. The printed circuit board according to claim 7, wherein: The value range of the lower boundary of the preset angle is 38° to 42°, the value range of the upper boundary of the preset angle is 48° to 52°, and the value range of the height constraint constant is 0.8 to 1.

2.

9. The printed circuit board according to claim 8, characterized in that The length of the middle line segment ranges from 2 to 4 , is the line width of the transmission line segment to be adjusted.

10. The printed circuit board according to claim 5, characterized in that The compensation line segment includes a semicircular arc, and both ends of the semicircular arc are respectively connected to the parallel segments on both sides. The radius of the semicircular arc satisfies the preset constraint conditions, so that after the compensation line segment is inserted, the length of the transmission line segment to be adjusted is equal to the length of the target transmission line segment, and the number of the inserted compensation line segments is minimized. The shape parameter of the compensation line segment includes the radius of the semicircular arc. The preset constraint conditions include: Where, represents the number of the inserted compensation segments, represents the radius of the semicircular arc, represents the length difference between the transmission line segment to be adjusted and the target transmission line segment when the compensation line segment is not inserted, represents the height constraint constant, Indicates the line distance between the transmission line segment to be adjusted and the target transmission line segment.

11. The printed circuit board according to claim 5, characterized in that The compensation line segment includes a first connecting line segment and a second connecting line segment, wherein one end of the first connecting line segment is connected to the parallel segment on one side of the compensation line segment, the other end of the first connecting line segment is connected to one end of the second connecting line segment to form a wedge-shaped protrusion, and the other end of the second connecting line segment is connected to the parallel segment on the other side of the compensation line segment; The height of the wedge-shaped protrusion, the inclination angle of the first connecting line segment, and the inclination angle of the second connecting line segment satisfy the preset constraints, so that the length of the transmission line segment to be adjusted is equal to the length of the target transmission line segment after the compensation line segment is inserted, and the number of inserted compensation line segments is minimized. The shape parameters of the compensation line segment include the height of the wedge-shaped protrusion, the inclination angle of the first connecting line segment, and the inclination angle of the second connecting line segment. The preset constraints include: Where, represents the number of the inserted compensation segments, represents the length difference between the transmission line segment to be adjusted and the target transmission line segment when the compensation line segment is not inserted, represents the height of the wedge-shaped protrusion, represents the line distance between the transmission line segment to be adjusted and the target transmission line segment, represents the inclination angle of the first connecting line segment, Indicates the inclination angle of the second connecting line segment.

12. The printed circuit board according to claim 1, wherein: The transmission line segment of the signal transmission line includes a first transmission line segment and a second transmission line segment connected to each other, the line width of the first transmission line segment is smaller than the line width of the second transmission line segment, the first transmission line segment and the second transmission line segment are connected by a gradient line segment, the first connection end of the gradient line segment is connected to the first transmission line segment, and the second connection end of the gradient line segment is connected to the second transmission line, and the line width of the gradient line segment gradually increases along the direction from the first connection end to the second connection end.

13. The printed circuit board according to claim 12, wherein: The width of the first connection end is the same as the line width of the first transmission line segment, and the connection end surface of the first connection end and the first transmission line segment coincide with each other. The width of the second connection end is the same as the line width of the second transmission line segment, and the connection end surface of the second connection end and the second transmission line segment coincide with each other.

14. The printed circuit board according to claim 1, wherein The signal transmission line is a differential signal line.

15. The printed circuit board according to claim 14, characterized in that The printed circuit board further includes a first electronic component and a second electronic component, and two ends of the differential signal line are connected to the first electronic component and the second electronic component respectively.

16. A server, characterized in that: Comprising the printed circuit board according to any one of claims 1 to 15.

17. A wiring compensation design method, characterized in that: Applicable to designing a printed circuit board according to any one of claims 1 to 15, comprising: Dividing the signal transmission line into a plurality of sequentially connected transmission line segments according to preset delay characteristics of the signal transmission line in different areas of the printed circuit board, wherein different transmission line segments of the same signal transmission line have different transmission delays per unit length, and transmission line segments of different signal transmission lines are arranged relative to each other and have the same transmission delay per unit length; The two opposite transmission line segments are routed for compensation so that the lengths of any two opposite transmission line segments are equal.

18. A wiring compensation design device, characterized in that: Applicable to designing a printed circuit board according to any one of claims 1 to 15, comprising: a transmission line segmentation module, configured to divide the signal transmission line into a plurality of sequentially connected transmission line segments according to preset delay characteristics of the signal transmission line in different areas of the printed circuit board, wherein different transmission line segments of the same signal transmission line have different transmission delays per unit length, and transmission line segments of different signal transmission lines are arranged relative to each other and have the same transmission delay per unit length; The segment compensation module is used to perform wiring compensation on two opposite transmission line segments so that the lengths of any two opposite transmission line segments are equal.

19. An electronic device, characterized in that: include: Memory for storing computer programs; A processor is configured to implement the steps of the wiring compensation design method as claimed in claim 17 when executing the computer program.

20. A computer-readable storage medium, characterized in that The computer-readable storage medium stores a computer program, wherein the computer program, when executed by a processor, implements the steps of the wiring compensation design method according to claim 17.

21. A computer program product, characterized in that The method comprises computer instructions for causing a computer to execute the steps of the wiring compensation design method according to claim 17 .

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