Differential wiring internal delay compensation structure, method and system

Abstract

The invention provides a differential routing internal delay compensation structure, method and system. The differential routing internal delay compensation structure comprises a first differential signal line and a second differential signal line, wherein the first differential signal line comprises a horizontal routing line and a snake-shaped routing line; the snakelike wire is formed by connecting a first wire, a second wire and a third wire; a certain angle is formed between the first wire and the horizontal direction and between the second wire and the horizontal direction, and the first wire and the second wire are symmetrical about the third wire; the horizontal wires and the snakelike wires are connected through a plurality of circular metal sheets and are used for reducing the propagation delay difference in differential signals. According to the differential routing internal delay compensation structure provided by the invention, the transmission quality of signals in a differential link can be improved.

Description

Technical Field

[0001] This application belongs to the technical field of PCB board routing, and relates to a differential routing internal delay compensation structure, method, and system. Background Art

[0002] In high-speed PCB design, differential routing technology is widely used in high-speed signal transmission to ensure signal quality and integrity. A differential trace consists of a pair of signal lines, usually labeled P (positive) and N (negative), which carry opposite signals respectively. Ideally, the signals on the P and N signal lines should reach the receiving end simultaneously to form a differential signal, thereby effectively suppressing common-mode interference.

[0003] However, in the actual PCB routing process, due to factors such as space limitations, impedance control requirements, and signal propagation speed differences, the routing lengths of the P and N signal lines are often difficult to be exactly the same, resulting in a time difference when the differential signal reaches the receiving end. This phenomenon is called internal delay difference (PN skew). The existence of PN skew will introduce a phase difference, reduce signal quality, affect signal integrity, and may cause some differential signals to be converted into common-mode signals, thus enhancing signal mode conversion and further reducing the signal anti-interference ability. Summary of the Invention

[0004] The purpose of this application is to provide a differential routing internal delay compensation structure, method, and system for improving the transmission quality of signals in a differential link.

[0005] In a first aspect, this application provides a differential routing internal delay compensation structure. The differential routing internal delay compensation structure includes a first differential signal line and a second differential signal line, wherein: the first differential signal line includes a horizontal trace and a serpentine trace; the serpentine trace is composed of a first trace, a third trace, and a second trace connected in sequence; the first trace forms a certain angle with the horizontal direction, the third trace is parallel to the horizontal direction, and the first trace and the second trace are symmetric with respect to the third trace; a plurality of circular metal pads are arranged at the connection between the horizontal trace and the serpentine trace for reducing the internal propagation delay difference of the differential signal.

[0006] In an implementation manner of the first aspect, the second differential signal line is routed along the horizontal direction, and a first distance between the horizontal trace and the second differential signal line is less than a second distance between the third trace and the second differential signal line.

[0007] In an implementation manner of the first aspect, the horizontal trace includes a first horizontal trace and a second horizontal trace. One end of the first trace far from the third trace is connected to the first horizontal trace, and one end of the second trace far from the third trace is connected to the second horizontal trace.

[0008] In an implementation of the first aspect, a first circular metal sheet is provided at the connection between the first trace and the first horizontal trace to reduce the differential impedance at the starting point of the serpentine trace; a second circular metal sheet is provided at the connection between the second trace and the second horizontal trace to reduce the differential impedance at the ending point of the serpentine trace.

[0009] In a second aspect, the present application provides a method for compensating the internal delay of a differential trace pair, which is implemented based on the above-mentioned structure for compensating the internal delay of a differential trace pair. The method for compensating the internal delay of a differential trace pair includes: obtaining the lengths of the horizontal trace, the serpentine trace, the second differential signal line, and the second spacing; obtaining the expected propagation delay difference inside the differential trace pair based on the lengths of the horizontal trace, the serpentine trace, and the second differential signal line; performing parameter scanning on the differential trace pair based on a differential trace model to obtain the actual propagation delay difference inside the differential trace pair; obtaining an absolute difference value based on the expected propagation delay difference inside the differential trace pair and the actual propagation delay difference inside the differential trace pair; and performing signal compensation on the differential trace pair based on the absolute difference value and the change in the differential impedance of the serpentine trace region.

[0010] In an implementation of the second aspect, the process of obtaining the expected propagation delay difference inside the differential trace pair based on the lengths of the horizontal trace, the serpentine trace, and the second differential signal line includes: obtaining the length difference between the first differential signal line and the second differential signal line based on the lengths of the horizontal trace, the serpentine trace, and the second differential signal line; and obtaining the expected propagation delay difference inside the differential trace pair based on the length difference and the signal propagation rate.

[0011] In an implementation of the second aspect, the radius of a circular metal sheet for compensating the delay of the serpentine trace region is obtained based on the absolute difference value.

[0012] In an implementation of the second aspect, obtaining the actual propagation delay difference inside the differential trace pair includes: obtaining the actual propagation delay difference inside the differential trace pair based on the differential signals and common-mode signals on the first differential signal line and the second differential signal line.

[0013] In an implementation of the second aspect, the differential signals and the common-mode signals are obtained based on the first signal propagation rate on the first differential signal line and the second signal propagation rate on the second differential signal line.

[0014] In a third aspect, the present application provides a differential trace pair internal delay compensation system, which is implemented based on the above differential trace pair internal delay compensation structure. The differential trace pair internal delay compensation system includes: a length acquisition module for acquiring the lengths of the horizontal trace, the serpentine trace, the second differential signal line, and the second pitch; a difference acquisition module for obtaining the length difference between the first differential signal line and the second differential signal line and the expected propagation delay difference within the differential trace pair based on the lengths of the horizontal trace, the serpentine trace, and the second differential signal line; a model scanning module for performing parameter scanning on the differential trace based on the differential trace model to obtain the actual propagation delay difference within the differential trace pair; a difference result acquisition module for obtaining an absolute difference value based on the expected propagation delay difference within the differential trace pair and the actual propagation delay difference within the differential trace pair; and a signal compensation module for compensating the differential trace based on the absolute difference value and the differential impedance change in the serpentine trace area.

[0015] As described above, the differential trace pair internal delay compensation structure, method, and system of the present application have the following beneficial effects:

[0016] The differential trace pair internal delay compensation structure provided by the present application enhances the delay compensation ability of the serpentine trace area, reduces the differential impedance in the serpentine trace area, reduces the internal propagation delay difference of the differential signals within the differential trace of the differential link, and improves the signal integrity of the differential link by constructing a serpentine trace based on a circular metal sheet, the symmetrically designed first trace and second trace in the serpentine trace, and the circular metal sheet structure connecting the horizontal trace and the serpentine trace. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It shows a schematic structural diagram of the traditional differential trace structure described in the embodiment of the present application.

[0018] Figure 2 It shows a schematic structural diagram of the traditional differential trace structure described in the embodiment of the present application.

[0019] Figure 3 It shows a schematic structural diagram of the differential trace pair internal delay compensation system described in the embodiment of the present application.

[0020] Figure 4 It shows a schematic structural diagram of the differential trace pair internal delay compensation structure described in the embodiment of the present application.

[0021] Figure 5 It shows a schematic process diagram of the differential trace pair internal delay compensation method described in the embodiment of the present application.

[0022] Figure 6 It shows a schematic structural diagram of the traditional differential trace structure described in the embodiment of the present application.

[0023] Figure 7 It shows a schematic structural diagram of the in-pair delay compensation structure for differential traces according to the embodiment of the present application.

[0024] Figure 8 It shows a schematic structural diagram of the conventional differential trace structure according to the embodiment of the present application.

[0025] Figure 9 It shows a schematic structural diagram of the in-pair delay compensation structure for differential traces according to the embodiment of the present application.

[0026] Figure 10 It shows a schematic structural diagram of the in-pair delay compensation system for differential traces according to the embodiment of the present application.

[0027] Description of component labels

[0028] 1 In-pair delay compensation system for differential traces

[0029] 11 Length acquisition module

[0030] 12 Difference acquisition module

[0031] 13 Model scanning module

[0032] 14 Difference result acquisition module

[0033] 15 Signal compensation module

[0034] Steps S11 to S15 Specific implementation manners

[0035] The following uses specific specific examples to illustrate the implementation manners of the present application. Those skilled in the art can easily understand other advantages and effects of the present application from the content disclosed in this specification. The present application can also be implemented or applied through other different specific implementation manners. Various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present application. It should be noted that, without conflict, the following embodiments and the features in the embodiments can be combined with each other.

[0036] It should be noted that the diagrams provided in the following embodiments only illustrate the basic concept of the present application in a schematic manner. Therefore, only the components related to the present application are shown in the diagrams, rather than being drawn according to the number, shape, and size of the components in actual implementation. The type, quantity, and ratio of each component in actual implementation can be arbitrarily changed, and the component layout type may also be more complex.

[0037] In high-speed PCB design, differential routing technology is widely used in high-speed signal transmission to ensure signal quality and integrity. Differential routing consists of a pair of signal lines, usually labeled P (positive) and N (negative), which carry opposite signals respectively. Ideally, the signals on the P and N signal lines should reach the receiving end simultaneously to form a differential signal, thereby effectively suppressing common-mode interference.

[0038] However, during the actual PCB routing process, see Figure 1 and Figure 2 , due to factors such as space limitations, impedance control requirements, and signal propagation speed differences, it is often difficult to make the routing lengths of the P and N signal lines exactly the same, resulting in a time difference when the differential signal reaches the receiving end. This phenomenon is called intra-pair delay difference (PN skew). The existence of PN skew will introduce a phase difference, reduce signal quality, affect signal integrity, and may cause some differential signals to be converted into common-mode signals, thereby enhancing signal mode conversion and further reducing the signal anti-interference ability.

[0039] To compensate for the routing length difference, designers usually adopt a serpentine routing design, that is, by adding bends to the shorter routing to make its length match that of the other routing. However, the traditional serpentine routing design will cause the electromagnetic field coupling to weaken at the corners, and the actual signal propagation path is shorter than the ideal path, thus exacerbating the PN skew problem.

[0040] At least for the above problems, the following embodiments of the present application provide a differential routing intra-pair delay compensation structure. The technical solutions in the embodiments of the present application will be described in detail below with reference to the accompanying drawings in the embodiments of the present application.

[0041] Figure 3 It shows a schematic structural diagram of a differential routing intra-pair delay compensation structure in an embodiment of the present application. As Figure 3 shown, the differential routing intra-pair delay compensation structure includes a first differential signal line and a second differential signal line, wherein: the first differential signal line includes a horizontal routing and a serpentine routing; the serpentine routing is composed of a first routing, a third routing, and a second routing connected in sequence; the first routing forms a certain angle with the horizontal direction, the third routing is parallel to the horizontal direction, and the first routing and the second routing are symmetric with respect to the third routing; a plurality of circular metal sheets are arranged at the connection between the horizontal routing and the serpentine routing for reducing the intra-pair propagation delay difference of the differential signal.

[0042] In an embodiment of the present application, the horizontal routing includes a first horizontal routing and a second horizontal routing. One end of the first routing away from the third routing is connected to the first horizontal routing, and one end of the second routing away from the third routing is connected to the second horizontal routing.

[0043] Exemplarily, the first differential signal line is, for example, the N signal line Diff_N_trace, and the second differential signal line is, for example, the P signal line Diff_P_trace. The first differential signal line includes a horizontal trace and a serpentine trace. The horizontal trace includes a first horizontal trace N1 and a second horizontal trace N2. The serpentine trace includes a first trace N3, a second trace N4, and a third trace N5. The horizontal trace and the serpentine trace are connected by circular metal pads, and the circular metal pads include a first circular metal pad and a second circular metal pad. The first trace N3 is connected to the first horizontal trace N1 through the first circular metal pad, and the second trace N4 is connected to the second horizontal trace N2 through the second circular metal pad.

[0044] Furthermore, a first circular metal pad is provided at the connection between the first horizontal trace and the first trace to reduce the differential impedance at the starting point of the serpentine trace. A second circular metal pad is provided at the connection between the second trace and the second horizontal trace to reduce the differential impedance at the ending point of the serpentine trace.

[0045] According to the above description, it can be known that the differential trace internal delay compensation structure provided by the present application enhances the delay compensation ability of the serpentine trace area, reduces the differential impedance of the serpentine trace area, reduces the difference in the internal propagation delay of the differential signals in the differential link trace, and improves the signal integrity of the differential link by constructing a serpentine trace based on circular metal pads, the symmetrically designed first trace and second trace in the serpentine trace, and the circular metal pad structure connecting the horizontal trace and the serpentine trace.

[0046] Figure 4 It is shown as a schematic structural diagram of the differential trace internal delay compensation structure in an embodiment of the present application. As Figure 4 shown, the second differential signal line runs horizontally, and the first distance between the horizontal trace and the second differential signal line is less than the second distance between the third trace and the second differential signal line.

[0047] Exemplarily, the first distance between the first horizontal trace N1 and the second differential signal line is S, and the distance between the first horizontal trace N1 and the second differential signal line is equal to the distance between the second horizontal trace N2 and the second differential signal line, that is, the first distance between the second horizontal N2 and the second differential signal line is S. The second distance between the horizontal part of the third trace N5 and the second differential signal line is S1, and the first distance S is less than the second distance S1.

[0048] The present application also provides a differential trace internal delay compensation method, and the differential trace internal delay compensation method is implemented based on the above differential trace internal delay compensation structure. Figure 5It is a schematic diagram showing the process of the internal delay compensation method for differential signal traces in an embodiment of the present application. As Figure 5 shown, the internal delay compensation method for differential signal traces includes:

[0049] S11, obtaining the lengths of the horizontal trace, the serpentine trace, the second differential signal line, and the second pitch.

[0050] Exemplarily, according to the design requirements of high-speed differential signals, determine the length sizes of the first horizontal trace N1, the second horizontal trace N2, the first trace N3 of the serpentine trace, and the size of the second pitch S1 between the third trace and the second differential signal line within the serpentine trace area.

[0051] S12, obtaining the expected propagation delay difference within the differential signal traces based on the lengths of the horizontal trace, the serpentine trace, and the second differential signal line. Due to PCB routing limitations and design requirements, there may also be slight differences in the lengths of the two traces, and such differences will cause differences in signal propagation time. Even if the trace lengths are the same, due to the influence of factors such as trace shape, corners, and vias, the signal propagation paths of the two traces may also be different, thus affecting the propagation delay. The expected propagation delay difference within the differential signal traces is the propagation delay difference expected to be achieved when the differential signal propagates on the two traces without the influence of external factors. Based on the expected propagation delay difference, it can help designers select appropriate trace lengths and structures to reduce the actual propagation delay difference. At the same time, comparing the actual propagation delay difference with the expected propagation delay difference can evaluate whether the performance of the differential signal traces meets the design requirements.

[0052] In an embodiment of the present application, the expected propagation delay difference within the differential signal traces is obtained according to the parameter indicators of the two traces. Among them, the process of obtaining the expected propagation delay difference within the differential signal traces based on the lengths of the horizontal trace, the serpentine trace, and the second differential signal line includes:

[0053] S121, obtaining the length difference between the first differential signal line and the second differential signal line based on the lengths of the horizontal trace, the serpentine trace, and the second differential signal line.

[0054] Exemplarily, based on the physical lengths of the differential signal traces, calculate the length difference between the first differential signal line Diff_N_trace and the second differential signal line Diff_P_trace, that is, gap_len = N1 + N2 + N3 + N4 + N5 - P1.

[0055] S122, obtaining the expected propagation delay difference within the differential signal traces based on the length difference and the signal propagation rate.

[0056] Exemplarily, based on the length difference gap_len and the signal propagation rate within the differential trace pair, the expected propagation delay difference within the differential trace pair is obtained, that is, the expected propagation delay difference within the differential trace pair physical_skew = gap_len / v.

[0057] S13. Based on the differential trace model, parameter scanning is performed on the differential trace to obtain the actual propagation delay difference within the differential trace pair. The actual propagation delay difference within the differential trace pair is the delay difference caused by the actual propagation of the differential signal on the two traces after the PCB layout and routing are completed. The performance of the differential trace can be evaluated through the actual propagation delay difference, and problems such as discontinuous differential trace impedance and signal reflection can be diagnosed.

[0058] Exemplarily, a differential trace model is established, parameter scanning is performed on the radii of the first circular metal sheet connecting the first horizontal trace and the first trace and the second circular metal sheet connecting the second trace and the second horizontal trace, and the actual propagation delay difference real_skew within the differential trace pair is obtained through simulation. Among them, the differential trace model can be constructed by three-dimensional electromagnetic field simulation software.

[0059] S14. Based on the expected propagation delay difference within the differential trace pair and the actual propagation delay difference within the differential trace pair, an absolute difference value is obtained. The absolute difference value is the absolute value of the difference between the expected propagation delay difference within the differential trace pair and the actual propagation delay difference within the differential trace pair, and this absolute value represents the effectiveness of the serpentine trace compensation scheme.

[0060] Exemplarily, based on the expected propagation delay difference physical_skew within the differential trace pair and the actual propagation delay difference real_skew within the differential trace pair, the absolute value of the difference between the expected propagation delay difference physical_skew within the differential trace pair and the actual propagation delay difference real_skew within the differential trace pair is calculated, that is, extra_skew = physical_skew - real_skew. The smaller the absolute value of extra_skew, the closer the physical length of the serpentine trace is to the length of the actual signal propagation path. The smaller the absolute difference value extra_skew, the more effective the serpentine trace compensation scheme is, the closer the actual propagation delay difference is to the expected value, and the better the timing performance of the differential signal.

[0061] S15. Based on the absolute difference value and the differential impedance change in the serpentine trace area, signal compensation is performed on the differential trace. Based on the differential impedance change in the serpentine trace area, a suitable radius r value is selected as the radius of the circular metal sheet. Based on the absolute difference value, the radius of the circular metal sheet is obtained, and the circular metal sheet is used for delay compensation of the serpentine trace area.

[0062] In some embodiments, the process of compensating signals for traces based on the in-differential trace internal delay compensation structure can be achieved through the following steps:

[0063] Step 1, calculate the expected propagation delay difference. Calculate the expected propagation delay difference physical_skew for the in-differential signal pair according to the trace lengths of the first differential signal line and the second differential signal line.

[0064] Step 2, construct a differential trace model. Use 3D electromagnetic field simulation software to establish a differential trace model, and design and add circular metal sheets at the starting and ending positions of the serpentine trace.

[0065] Step 3, parameter scanning. Perform parameter scanning on the radius of the circular metal sheet to obtain the actual propagation delay difference real_skew for the in-differential signal pair.

[0066] Step 4, radius selection. Calculate the absolute value of the difference extra_skew = physical_skew - real_skew based on the expected propagation delay difference physical_skew and the actual propagation delay difference real_skew for the in-differential signal pair, and select the radius r value of the circular metal sheet based on extra_skew, that is, select the radius r value that minimizes extra_skew as the optimal radius of the circular metal sheet.

[0067] Step 5, optimize the differential trace design. Design the circular metal sheet according to the optimal radius and add it to the starting and ending positions of the serpentine trace for signal compensation.

[0068] In some embodiments, please refer to Figure 6 and Figure 7 , the expected propagation path of the signal for the serpentine trace after adding the circular metal sheet is the blue solid line, and the actual propagation path of the signal is the red dashed line. It can be seen that the expected propagation path of the signal at the red dashed line is equal to the actual propagation path of the signal of the blue solid line, thereby eliminating the PN skew and achieving complete compensation of the PN skew. Through electromagnetic field coupling of differential signals, the smaller the distance between differential signals, the stronger the coupling. By increasing the circular metal sheet, the distance between differential signals at the corner can be reduced, making S2 < S1, thereby enhancing the electromagnetic field coupling of differential signals. By enhancing the electromagnetic field coupling, the signal propagation paths on the P signal line and the N signal line become more consistent, ensuring signal edge alignment, eliminating the PN skew, effectively improving the signal timing performance and integrity, reducing the bit error rate, and weakening the signal mode conversion.

[0069] In some embodiments, the differential signal and the common-mode signal are obtained based on the first signal propagation rate on the first differential signal line and the second signal propagation rate on the second differential signal line. The voltage of the differential signal pair is obtained according to the differential signal component and the common-mode signal component.

[0070] Specifically, please refer to Figure 8 , in the traditional differential trace structure, when the edges of the first differential signal line and the second differential signal line are not aligned, there will be an internal delay difference, and at this time, the PN skew is not 0. In the case of an internal delay difference, the differential signal component v_diff between the differential signal pairs = V1 - V2. Due to the error in the differential signal edge, when the differential signals are subtracted, part of the differential signal is converted into a common-mode signal, and the common-mode signal will be converted into a differential signal, that is, the signal mode conversion will be enhanced. Among them, the differential signal component v_diff represents the voltage difference between the P signal line and the N signal line.

[0071] Please continue to refer to Figure 9 , when the circular metal sheet is added, the edges of the first differential signal line and the second differential signal line are aligned, and there will be no internal delay difference, and the PN skew is 0. At this time, the differential signal v_diff between the differential signal pairs = V1 - V2, and the common-mode signal v_com = (V1 + V2) / 2. v_com is the common-mode signal component, representing the average value of the voltages of the P signal line and the N signal line. The voltage V1 on the P signal line = v_com + v_diff / 2, that is, it is composed of the common-mode signal component and half of the differential signal component. The voltage V2 on the N signal line = v_com - v_diff / 2, which is composed of the common-mode signal component and half of the differential signal component. By calculating the common-mode signal component and the differential signal component separately, the common-mode interference can be better controlled, and by controlling the common-mode interference, the reliability of signal transmission and the integrity of the signal can be improved.

[0072] Next, a specific example will be used to introduce in detail the differential trace internal delay compensation structure and method provided by the embodiments of the present application. It should be noted that the content in this example is only used to explain and illustrate the differential trace internal delay compensation structure and method provided by the embodiments of the present application, rather than to limit the protection scope of the present application. In specific applications, corresponding steps can be added or deleted based on actual needs on the basis of this example.

[0073] High-speed USB interfaces need to transfer a large amount of data. However, due to factors such as differences in PCB wiring lengths, PN skew may occur in differential signal pairs (D+ and D-), resulting in a decline in signal quality. Therefore, a suitable circular metal sheet is designed according to the spacing and corner size of the differential signal lines, and the circular metal sheet is added to the corners of the D+ and D- lines. The delay compensation in the differential signal lines is verified by testing the signal integrity parameters of the D+ and D- lines to ensure that the PN skew is effectively compensated. At the same time, the design of the circular metal sheet can be further optimized based on the test results to obtain the best performance for data transmission of the high-speed USB interface.

[0074] In summary, the internal delay compensation structure and method for differential traces provided in this application compensate for the difference in trace lengths by adding serpentine traces to the shorter traces, and enhance the electromagnetic field coupling by adding circular metal sheets at the starting and ending positions of the corners of the serpentine traces. Utilizing the coupling effect of the odd-mode electromagnetic field to change the signal propagation path, it reduces the difference between the actual signal propagation path length and the physical length of the serpentine trace under the ideal path, effectively compensating for the difference in the internal propagation delay of the differential signal and reducing the mode conversion of the differential signal. The added circular metal sheet reduces the differential signal spacing at the corner, enabling the signals on the P and N signal lines to interact more closely with each other, thus ensuring the alignment of signal edges, reducing the differential impedance at the starting and ending points of the serpentine trace corners, pulling down the overall differential impedance in the serpentine trace area, and reducing the signal reflection caused by impedance fluctuations. Without changing the original wiring space of the PCB, adding circular copper sheets at the starting and ending points of the serpentine trace enhances the delay compensation ability of the serpentine trace and can reduce the differential impedance in the serpentine trace area, efficiently and at zero cost improving the signal integrity of the differential link. The internal delay compensation structure for differential traces of this application can be applied to serpentine traces of various shapes and sizes, making it more flexible.

[0075] The protection scope of the internal delay compensation method for differential traces described in the embodiments of this application is not limited to the execution order of the steps listed in this embodiment. Any solution achieved by adding or reducing steps of the prior art and replacing steps according to the principles of this application is included in the protection scope of this application.

[0076] The embodiments of this application also provide an internal delay compensation system for differential traces. The internal delay compensation system for differential traces is implemented based on the above internal delay compensation structure for differential traces. The internal delay compensation system for differential traces can implement the internal delay compensation method for differential traces described in this application. However, the implementation devices of the internal delay compensation method for differential traces described in this application include, but are not limited to, the structure of the internal delay compensation system for differential traces listed in this embodiment. Any structural deformation and replacement of the prior art made according to the principles of this application are included in the protection scope of this application.

[0077] Figure 10 Shown is a schematic structural diagram of the in-pair delay compensation system for differential traces in an embodiment of the present application. As Figure 10 shown, the in-pair delay compensation system for differential traces includes: a length acquisition module, a difference acquisition module, a model scanning module, a difference result acquisition module, and a signal compensation module. Among them, the length acquisition module is used to acquire the lengths of the horizontal trace, the serpentine trace, the second differential signal line, and the second pitch. The difference acquisition module is used to obtain the length difference between the first differential signal line and the second differential signal line and the expected propagation delay difference within the differential trace pair based on the lengths of the horizontal trace, the serpentine trace, and the second differential signal line. The model scanning module is used to perform parameter scanning on the differential trace based on the differential trace model to obtain the actual propagation delay difference within the differential trace pair. The difference result acquisition module is used to obtain the absolute difference value based on the expected propagation delay difference within the differential trace pair and the actual propagation delay difference within the differential trace pair. The signal compensation module is used to perform signal compensation on the differential trace based on the absolute difference value and the differential impedance change in the serpentine trace area.

[0078] It should be noted that Figure 10 each module in the in-pair delay compensation system 1 for differential traces shown corresponds one by one to the steps in Figure 5 the in-pair delay compensation method for differential traces, which will not be elaborated here.

[0079] In several embodiments provided by the present application, it should be understood that the disclosed system, device, or method can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the division of modules / units is only a logical function division. In actual implementation, there may be other division methods. For example, multiple modules or units can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the couplings or direct couplings or communication connections shown or discussed with each other can be through some interfaces. The indirect couplings or communication connections of devices or modules or units can be in electrical, mechanical, or other forms.

[0080] The modules / units described as separate components may or may not be physically separated. The components shown as modules / units may or may not be physical modules, that is, they can be located in one place, or they can be distributed to multiple network units. Some or all of the modules / units can be selected according to actual needs to achieve the purpose of the embodiments of the present application. For example, in each embodiment of the present application, the functional modules / units can be integrated in a processing module, or each module / unit can exist physically alone, or two or more modules / units can be integrated in one module / unit.

[0081] Those of ordinary skill in the art should also be able to further realize that the units and algorithm steps of each example described in combination with the embodiments disclosed herein can be implemented by electronic hardware, computer software, or a combination of the two. To clearly illustrate the interchangeability of hardware and software, the composition and steps of each example have been generally described according to functions in the above description. Whether these functions are executed in a hardware or software manner depends on the specific application and design constraints of the technical solution. Professional technicians can use different methods to implement the described functions for each specific application, but such implementation should not be considered to exceed the scope of this application.

[0082] The embodiments of the present application also provide a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, it implements the differential trace pair internal delay compensation method provided by the embodiments of the present application. Those of ordinary skill in the art can understand that all or part of the steps in the method for implementing the above embodiments can be completed by instructing the processor through a program. The described program can be stored in a computer-readable storage medium. The storage medium is a non-transitory medium, such as random access memory, read-only memory, flash memory, hard disk, solid-state drive, magnetic tape, floppy disk, optical disc, and any combination thereof. The above storage medium can be any available medium that can be accessed by a computer or a data storage device such as a server or a data center that integrates one or more available media. The available medium can be a magnetic medium (e.g., floppy disk, hard disk, magnetic tape), an optical medium (e.g., digital video disc (DVD)), or a semiconductor medium (e.g., solid state disk (SSD)), etc.

[0083] The descriptions of the processes or structures corresponding to the above respective drawings have their own focuses. For parts not detailed in a certain process or structure, reference can be made to the relevant descriptions of other processes or structures.

[0084] The above embodiments are only illustrative of the principles and effects of the present application, and are not used to limit the present application. Any person familiar with this technology can modify or change the above embodiments without departing from the spirit and scope of the present application. Therefore, all equivalent modifications or changes completed by those with ordinary knowledge in the technical field without departing from the spirit and technical idea disclosed by the present application should still be covered by the claims of the present application.

Claims

1. A delay compensation structure within a differential pair, characterized in that: The delay compensation structure within the differential pair includes a first differential signal line and a second differential signal line, wherein: The first differential signal line includes a horizontal line and a serpentine line; The serpentine routing is composed of a first routing, a third routing and a second routing connected in sequence; the first routing forms a certain angle with the horizontal direction, the third routing is parallel to the horizontal direction, and the first routing and the second routing are symmetrical with respect to the third routing; A plurality of circular metal sheets are provided at the connection between the horizontal routing and the serpentine routing, so as to reduce the propagation delay difference within the differential signal pair.

2. The delay compensation structure within a differential pair according to claim 1, characterized in that: The second differential signal line is routed in a horizontal direction, and a first distance between the horizontal route and the second differential signal line is smaller than a second distance between the third route and the second differential signal line.

3. The delay compensation structure within a differential pair according to claim 1, characterized in that: The horizontal routing includes a first horizontal routing and a second horizontal routing, wherein one end of the first routing away from the third routing is connected to the first horizontal routing, and one end of the second routing away from the third routing is connected to the second horizontal routing.

4. The delay compensation structure within a differential pair according to claim 3, characterized in that: A first circular metal sheet is provided at the connection between the first routing line and the first horizontal routing line, so as to reduce the differential impedance at the starting point of the serpentine routing line; a second circular metal sheet is provided at the connection between the second routing line and the second horizontal routing line, so as to reduce the differential impedance at the end point of the serpentine routing line.

5. A method for delay compensation within a differential pair, characterized in that: Based on the delay compensation structure within the differential routing pair according to any one of claims 1 to 4, the delay compensation method within the differential routing pair includes: Obtaining the lengths of the horizontal line, the serpentine line, the second differential signal line, and the second spacing; Obtaining an expected propagation delay difference within a differential routing pair based on the lengths of the horizontal routing, the serpentine routing, and the second differential signal line; Perform parameter scan on the differential routing based on the differential routing model to obtain the actual propagation delay difference within the differential routing pair; Obtaining an absolute difference value based on an expected propagation delay difference within the differential routing pair and an actual propagation delay difference within the differential routing pair; Signal compensation is performed on the differential routing based on the absolute difference value and the differential impedance change in the serpentine routing area.

6. The method for delay compensation within a differential pair according to claim 5, characterized in that: The process of obtaining the expected propagation delay difference within the differential routing pair based on the lengths of the horizontal routing, the serpentine routing, and the second differential signal line includes: Obtaining a length difference between the first differential signal line and the second differential signal line based on the lengths of the horizontal line, the serpentine line, and the second differential signal line; An expected propagation delay difference within the differential trace pair is obtained based on the length difference and a signal propagation rate.

7. The method for compensating delay within a differential pair according to claim 5, characterized in that: Also includes: The radius of a circular metal sheet is acquired based on the absolute difference value, and the circular metal sheet is used to perform delay compensation on the serpentine routing area.

8. The method for delay compensation within a differential pair according to claim 5, characterized in that: Obtaining the actual propagation delay difference within the differential routing pair includes: obtaining the actual propagation delay difference within the differential routing pair based on the differential signal and the common mode signal on the first differential signal line and the second differential signal line.

9. The method for delay compensation within a differential pair according to claim 8, characterized in that: Also includes: The differential signal and the common mode signal are acquired based on a first signal propagation rate on the first differential signal line and a second signal propagation rate on the second differential signal line.

10. A differential line pair delay compensation system, characterized in that: Based on the delay compensation structure within the differential pair according to any one of claims 1 to 4, the delay compensation system within the differential pair comprises: A length acquisition module, used to acquire the lengths of the horizontal line, the serpentine line, the second differential signal line, and the second spacing; A difference acquisition module, configured to acquire a length difference between the first differential signal line and the second differential signal line and an expected propagation delay difference within a differential line pair based on the lengths of the horizontal line, the serpentine line, and the second differential signal line; A model scanning module is used to perform parameter scanning on the differential routing based on the differential routing model to obtain the actual propagation delay difference within the differential routing pair; A difference result acquisition module, used for acquiring an absolute difference value based on an expected propagation delay difference within the differential routing pair and an actual propagation delay difference within the differential routing pair; The signal compensation module is used to perform signal compensation on the differential routing based on the absolute difference value and the differential impedance change in the serpentine routing area.

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