Differential phase matching structure and communication system

Abstract

The invention provides a differential phase matching structure and a communication system. The differential phase matching structure is arranged on a differential channel of the PCB, the differential phase matching structure comprises a first differential signal line and a second differential signal line, and the differential channel comprises a first transmission line and a second transmission line; the first differential signal line is formed by connecting a first wire, a second wire, a third wire, a fourth wire and a fifth wire, the left end of the first wire is connected with the first section of the first transmission line, and the right end of the fifth wire is connected with the second section of the first transmission line; the left end of the second differential signal line is connected with the first section of the second transmission line, and the right end of the second differential signal line is connected with the second section of the second transmission line; the first differential signal line and the second differential signal line form a bump structure and are used for accurately matching phases on the differential channels.

Description

Technical Field

[0001] This application belongs to the technical field of PCB design, and relates to a differential phase matching structure and a communication system. Background Art

[0002] In the field of printed circuit board (PCB) design, ensuring phase matching of signal transmission is crucial. As signals are transmitted step by step from the sending end to the receiving end, they must remain synchronized to avoid data transmission errors and performance degradation. However, due to the complex layout and diverse geometries of the internal traces of the PCB, signals often face the challenge of phase mismatch. This mismatch may occur at the corners, branch points, or any other area where the geometry changes abruptly, thus affecting the signal integrity and reliability. Therefore, how to accurately achieve phase matching within the differential channel has become an urgent problem to be solved in PCB design. Summary of the Invention

[0003] This application provides a differential phase matching structure and a communication system for precisely matching differential signals within a differential channel.

[0004] In a first aspect, this application provides a differential phase matching structure disposed on a differential channel of a PCB board. The differential phase matching structure includes a first differential signal line and a second differential signal line. The first differential signal line and the second differential signal line form a bulge structure for matching the phase on the differential channel. The differential channel includes a first transmission line and a second transmission line. The first differential signal line is connected by a first trace, a second trace, a third trace, a fourth trace, and a fifth trace. The left end of the first trace is connected to the first segment of the first transmission line, and the right end of the fifth trace is connected to the second segment of the first transmission line. The left end of the second differential signal line is connected to the first segment of the second transmission line, and the right end of the second differential signal line is connected to the second segment of the second transmission line. The distance between the first trace and the second differential signal line is equal to the distance between the fifth trace and the second differential signal line, and the distance between the first trace and the second differential signal line is a first distance. The distance between the third trace and the second differential signal line is a second distance. The second distance is greater than the first distance. The first distance and the second distance are used to adjust the phase of the differential channel.

[0005] In one implementation of the first aspect, the second differential signal line further includes a sixth trace located in the middle of the second differential signal line, and the center position of the sixth trace and the center position of the third trace are in a vertically corresponding relationship.

[0006] In an implementation of the first aspect, the line width of the sixth trace is equal to that of the third trace; the line length of the sixth trace is N times the line width of the first differential signal line, and the line width of the sixth trace is M times the line width of the first differential signal line, which is used to compensate the phase of the differential signal line, where the value ranges of N and M are greater than 0.

[0007] In an implementation of the first aspect, the minimum line length of the sixth trace is equal to that of the third trace.

[0008] In an implementation of the first aspect, the second pitch is K times the first pitch, which is used to adjust the phase of the differential signal line.

[0009] In an implementation of the first aspect, the minimum pitch of the second pitch is twice that of the first pitch; the maximum pitch of the second pitch is six times that of the first pitch.

[0010] In an implementation of the first aspect, the angle between the second trace and the horizontal direction is in the range of 45° to 90°; the second trace and the fourth trace are symmetric about the third trace, and the third trace is parallel to the horizontal direction.

[0011] In an implementation of the first aspect, the line width of the first trace is equal to that of the fifth trace; the line width of the second trace is equal to that of the fourth trace.

[0012] In an implementation of the first aspect, the line width of the first transmission line is equal to that of the second transmission line; the minimum line length of the third trace is twice the line width of the first transmission line; the maximum line length of the third trace is ten times the line width of the first transmission line.

[0013] In a second aspect, the present application provides a communication system, which includes a sending end, a receiving end, a differential channel, and a differential phase matching structure; the sending end and the receiving end are arranged at both ends of the differential channel; the differential phase matching structure is connected to the differential channel and is arranged on one side of the sending end, and / or on one side of the receiving end, and / or at an intermediate position of the differential channel.

[0014] As described above, the differential phase matching structure and the communication system of the present application have the following beneficial effects:

[0015] According to the above description, it can be known that the differential phase matching structure provided by the present application can match and correct the differential phase of the differential channel on the PCB board by adjusting the distances between the first trace and the second trace and the second differential signal line and between the third trace and the second differential signal line, so as to achieve precise phase matching. Description of the Drawings

[0016] Figure 1 It shows a schematic diagram of the result of the setting position of the differential phase matching structure described in the embodiment of the present application.

[0017] Figure 2 It shows a schematic diagram of the structure of the differential phase matching structure described in the embodiment of the present application.

[0018] Figure 3 It shows a schematic diagram of the structure of the differential phase matching structure described in the embodiment of the present application.

[0019] Figure 4 It shows a schematic diagram of the structure of the differential phase matching structure described in the embodiment of the present application.

[0020] Figure 5 It shows a schematic diagram of the structure of the differential phase matching structure described in the embodiment of the present application.

[0021] Figure 6 It shows a schematic diagram of the structure of the differential phase matching structure described in the embodiment of the present application.

[0022] Figure 7 It shows a schematic diagram of the structure of the differential phase matching structure described in the embodiment of the present application.

[0023] Figure 8 It shows a schematic diagram of the structure of the communication system described in the embodiment of the present application.

[0024] Description of component numbers

[0025] 1 Communication system

[0026] 11 Transmitter

[0027] 12 Receiver

[0028] 13 Differential phase matching structure

[0029] 14 Differential channel Detailed implementation manners

[0030] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention. Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed present invention, but merely represents selected embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0031] The following uses specific specific examples to illustrate the embodiments 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 embodiments. 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.

[0032] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be understood as a limitation to the present invention.

[0033] In addition, the terms "first" and "second" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present invention, "a plurality" means two or more, unless otherwise specifically defined.

[0034] In the present invention, unless otherwise clearly specified or limited, the terms "mounted", "connected", "coupled", "fixed", etc. shall be construed broadly. For example, it may be a fixed connection, a detachable connection, or an integral one; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the internal communication of two components or the interaction relationship between two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0035] In the present invention, unless otherwise clearly specified or limited, the first feature being "on" or "under" the second feature may include the direct contact between the first and second features, or may include the situation where the first and second features are not in direct contact but in contact through additional features therebetween. Moreover, the first feature being "above", "over" and "on top of" the second feature includes that the first feature is directly above and obliquely above the second feature, or merely means that the horizontal height of the first feature is higher than that of the second feature. The first feature being "under", "beneath" and "underneath" the second feature includes that the first feature is directly below and obliquely below the second feature, or merely means that the horizontal height of the first feature is lower than that of the second feature.

[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 types, quantities and proportions of the components in actual implementation can be arbitrarily changed, and the component layout type may also be more complex.

[0037] In the design of a printed circuit board (PCB), the phase matching of signal transmission is a crucial factor. During the process of signal transmission from the sending end to the receiving end, due to the complexity of the internal traces of the PCB and the changes in geometric shapes, the problem of phase mismatch often occurs. This phase mismatch is mainly caused by the following factors:

[0038] 1) Trace corner effect: Phase mismatch occurs at the corners of the transmission lines inside the PCB. Due to the existence of the corners, the propagation speed of the signal changes at the corners, resulting in a phase difference before and after the transmission line near the sending end. This phase difference will increase the signal noise of the transmission lines inside the PCB. If not corrected, the signal received at the receiving end will carry a large amount of noise, affecting the signal integrity and system performance.

[0039] 2) Unequal-length differential lines: In differential signal transmission, the P line and the N line form a pair of differential lines. At the corner of the PCB structure, these two lines will become the inner line and the outer line respectively. Due to the different corner radians, the actual transmission lengths of the differential lines inside the PCB will be unequal. The inner line can be a P signal line or an N signal line, and the outer line can also be a P signal line or an N signal line.

[0040] 3) Impedance change: To adjust the impedance of the signal line, designers usually adopt various methods. The traditional bulge setting is a commonly used means, which adjusts the impedance by changing the distance between the differential signal lines. The bulge structure can increase the impedance between the differential signal lines, but at the same time it will also cause an increase in the line spacing, which may cause a phase mismatch problem between the signal lines.

[0041] At least for the above problems, the following embodiments of the present application provide a differential phase matching structure for matching the differential signals in the differential channel. The principle and implementation manner of a differential phase matching structure of this embodiment will be described in detail below with reference to the accompanying drawings, so that those skilled in the art can understand the differential phase matching structure of this embodiment without creative labor.

[0042] As Figure 1 and 2 shown, this embodiment provides a differential phase matching structure, which is arranged on the differential channel of the PCB board. The differential phase matching structure includes a first differential signal line and a second differential signal line. The first differential signal line and the second differential signal line form a bulge structure for matching the phase on the differential channel. The differential channel includes a first transmission line and a second transmission line. The first differential signal line is connected by a first trace, a second trace, a third trace, a fourth trace, and a fifth trace. The left end of the first trace is connected to the first section of the first transmission line, and the right end of the fifth trace is connected to the second section of the first transmission line. The left end of the second differential signal line is connected to the first section of the second transmission line, and the right end of the second differential signal line is connected to the second section of the second transmission line. The distance between the first trace and the second differential signal line is equal to the distance between the fifth trace and the second differential signal line. The distance between the first trace and the second differential signal line is the first distance. The distance between the third trace and the second differential signal line is the second distance. The second distance is greater than the first distance. The first distance and the second distance are used to adjust the phase of the differential channel.

[0043] In an embodiment of the present application, both ends of the differential channel are a transmitting end and a receiving end. The differential phase matching structure is disposed on one side of the differential channel at the transmitting end, and / or on one side of the differential channel at the receiving end, and / or on the differential channel between the transmitting end and the receiving end. For example, the transmitting end is a BGA area and the receiving end is a connector, or the transmitting end is a connector and the receiving end is a BGA area.

[0044] Exemplarily, the signal transmission lines are a P signal line and an N signal line. There is no distinction between inside and outside for the P signal line and the N signal line on the differential pass. The P signal line can be an inner line or an outer line. The N signal line can be an inner line or an outer line. The first differential signal line can be a P signal line or an N signal line. The second differential signal line can be a P signal line or an N signal line.

[0045] Exemplarily, the width of the first trace is equal to the width of the first transmission line, the width of the fifth trace is equal to the width of the second transmission line, the width of the first transmission line is equal to the width of the second transmission line, and the width of the second differential signal line is equal to the width of the second transmission line.

[0046] Exemplarily, the first trace, the second trace, and the third trace can be a P signal line or an N signal line.

[0047] According to the above description, it can be known that the differential phase matching structure provided by the present application can perform matching correction on the differential phase of the differential channel on the PCB board by adjusting the distances between the first trace and the second trace and the second differential signal line and between the third trace and the second differential signal line, so as to achieve precise phase matching.

[0048] In an embodiment of the present application, the second differential signal line further includes a sixth trace. The sixth trace is located in the middle of the second differential signal line, and the central position of the sixth trace and the central position of the third trace are in a vertically corresponding relationship.

[0049] Exemplarily, the fourth trace is located on the second differential signal line. The fourth trace can be a P signal line or an N signal line.

[0050] In an embodiment of the present application, the width of the sixth trace is equal to the width of the third trace; the line length of the sixth trace is N times the width of the first differential signal line, and the width of the sixth trace is M times the width of the first differential signal line, for compensating the phase of the differential signal line, where the value ranges of N and M are greater than 0. The minimum line length of the sixth trace is equal to the minimum line length of the third trace.

[0051] In an embodiment of the present application, the second pitch is K times the first pitch, which is used to adjust the phase of the differential signal line, where the value range of K is greater than 0. Exemplarily, the minimum pitch of the second pitch is twice the first pitch; the maximum pitch of the second pitch is six times the first pitch.

[0052] In an embodiment of the present application, the angle between the second trace and the horizontal direction is in the range of 45° to 90°; the second trace and the fourth trace are symmetric with respect to the third trace. The third trace is parallel to the horizontal direction, the third trace is approximately parallel to the horizontal direction, and the angle between the third trace and the horizontal direction is less than the error range allowed by the user.

[0053] Specifically, the angle between the left end of the second trace and the horizontal direction is in the range of 45° to 90°; the angle between the right end of the fourth trace and the horizontal direction is in the range of 45° to 90°.

[0054] In an embodiment of the present application, the line width of the first transmission line is equal to the line width of the second transmission line; the minimum line length of the third trace is twice the line width of the first transmission line; the maximum line length of the third trace is ten times the line width of the first transmission line. The line width of the first trace is equal to the line width of the fifth trace; the line width of the second trace is equal to the line width of the fourth trace.

[0055] There are inner lines and outer lines for the first transmission line and the second transmission line in the PCB board. The generation of the corner arc causes the differential lines to have unequal lengths during transmission in the PCB. The impedance between the differential signal lines is changed through the differential phase matching structure, increasing the impedance of the differential signal lines. At the same time, the differential phase is matched and adjusted due to the impedance change caused by the change in the line pitch. The following provides five differential phase matching structures, and a suitable optimization structure is selected according to the actual transmission trace requirements to correct and adjust the differential phase.

[0056] Embodiment 1, please refer to Figure 3, the first differential signal line is, for example, a P signal line, and the second differential signal line is, for example, an N signal line. The left end of the first trace is connected to the first transmission line. The included angle between the left end of the second trace A and the horizontal direction is α. The first trace, the second trace A, the third trace C, the fourth trace B, and the fifth trace are connected in sequence. The distance between the first trace and the second differential signal line is the first distance S. The distance between the fifth trace and the second differential signal line is the first distance S. The distance between the third trace and the second differential signal line is the second distance H. The trace lengths of the second trace A and the fourth trace B are equal. The line widths of the first differential signal line and the second differential signal line are w, that is, the line widths of the first trace, the second trace, the third trace, the fourth trace, and the fifth trace are w, and the trace widths of all traces on the first differential signal line do not change. The trace length of the third trace C is L1. The angle α varies within the range of 45° to 90°. The range of the second distance H is between twice the first distance S and six times the first distance S, that is, [2S, 6S]. The trace length L1 of the third trace C is between 2w and 10w, that is, [2w, 10w].

[0057] Specifically, the adjustment of the bulge A section and the bulge B section is as follows: The included angle α between the bulge A section of the differential phase matching structure and the horizontal direction can be adjusted, so that the length of the first differential signal line in this area changes. The bulge B section is connected to the bulge A section to further adjust the length of the first differential signal line. By adjusting α and the design of the bulge B section, the total length of the line P can be controlled to be close to or equal to the length of the line N, so as to achieve the length matching of the differential signal lines. The adjustment of the length L1 of the third trace C is as follows: By adjusting the length L1 of the third trace C, the total length of the first differential signal line can be further controlled. By adjusting L1, the lengths of the first differential signal line and the second differential signal line can be made completely matched, improving the accuracy of phase matching. The adjustment of the second distance H is as follows: The second distance H between the third trace and the second differential signal line is related to the transmission characteristics of the signal. By adjusting the second distance H, the coupling degree between the first differential signal line and the second differential signal line can be controlled, thereby further affecting the phase of the signal. The large bulge structure of the first differential signal line can change the impedance of the trace by adjusting the line width and the distance, so that it matches the impedance of the second differential signal line. By adjusting the angle of the bulge A section, the design of the bulge B section, and the length of the third trace C, the total length of the first differential signal line can be controlled to be close to or equal to the length of the second differential signal line. By adjusting the distance H, the coupling degree between the line P and the line N can be controlled, thereby affecting the phase of the signal.

[0058] Embodiment 2, please refer to Figure 4, the first differential signal line is, for example, a P signal line, and the second differential signal line is, for example, an N signal line. The left end of the first trace is connected to the first transmission line. The included angle between the left end of the second trace A and the horizontal direction is α. The first trace, the second trace A, the third trace C, the fourth trace B, and the fifth trace are connected in sequence. The distance between the first trace and the second differential signal line is the first distance S. The distance between the fifth trace and the second differential signal line is the first distance S. The distance between the third trace and the second differential signal line is the second distance H. The trace length of the second trace A is equal to the trace length of the fourth trace B. The trace widths of the first trace, the second trace, the fourth trace, the fifth trace, and the second differential signal line are w. The trace length of the third trace C is L1, and the line width is c1. The trace widths of the second trace and the fourth trace do not change. The angle α varies within the range of 45° to 90°. The variation range of the second distance H is between twice the first distance S and six times the first distance S, that is, [2S, 6S]. The line width c1 of the third trace is between w and 2w, that is, [w, 2w].

[0059] Specifically, the adjustment of the bulge A section and the bulge B section is manifested as follows: By the angle α of the bulge A section and the bulge B section, the total length of the first differential signal line can be adjusted to be equal to the length of the second differential signal line, so as to achieve length matching. The adjustment of the length and width of the third trace C is manifested as follows: By adjusting the length L1 and the line width c1 of the third trace C, the total length and impedance of the first differential signal line can be further controlled to match the length and impedance of the second differential signal line. The adjustment of the second distance H is manifested as follows: By adjusting the second distance H, the coupling degree between the first differential signal line and the second differential signal line can be controlled to optimize phase matching. In summary, by the bulge structure of the first differential signal line, the adjustment of the length and width of the third trace C, and the control of the distance H, the impedance of the trace can be changed. The differential pair line distance changes from the normal distance value S to the H distance at the bulge, and the line width of the bulge C section can be increased to resist impedance mutation. By adjusting the angle of the bulge A section, the design of the bulge B section, and the length of the third trace C, the total length of the first differential signal line can be controlled to be close to or equal to the length of the second differential signal line. By adjusting the second distance H, the coupling degree between the first differential signal line and the second differential signal line can be controlled, thereby affecting the phase of the signal.

[0060] Embodiment 3, please refer to Figure 5, the first differential signal line is, for example, a P signal line, and the second differential signal line is, for example, an N signal line. The left end of the first trace is connected to the first transmission line. The angle between the left end of the second trace A and the horizontal direction is α. The first trace, the second trace A, the third trace C, the fourth trace B, and the fifth trace are connected in sequence. The distance between the first trace and the second differential signal line is the first distance S. The distance between the fifth trace and the second differential signal line is the first distance S. The distance between the third trace and the second differential signal line is the second distance H. The trace length of the second trace A is equal to the trace length of the fourth trace B. The line widths of the first trace, the fifth trace, and the second differential signal line are w. The trace length of the third trace is L1, the line width of the second trace is a1, the line width of the third trace is c1, the line width of the fourth trace is b1, and the line widths of the second trace, the third trace, and the fourth trace change. The line width a1 of the second trace is equal to the line width b1 of the fourth trace. The angle α varies within the range of 45° to 90°. The variation range of the second distance H is between twice the first distance S and six times the first distance S, that is, [2S, 6S]. The variation range of the trace length L1 of the third trace is between twice w and ten times w, that is, [2w, 10w]. The variation range of the line width a1 of the second trace is between w and 2w, that is, [w, 2w]. The line width c1 of the third trace is between w and 2w, that is, [w, 2w].

[0061] Specifically, the characteristic impedance of the trace can be changed by the line widths of the bulges A, B, and C, so that it matches the impedance of the adjacent trace at the corner or width change. When the impedances of the A, B, and C segments match the impedance of the adjacent trace, the impedance mutation can be effectively reduced, thereby reducing signal reflection and transmission loss and improving signal transmission quality. At the same time, adjusting the line widths of the bulges A, B, and C can make the signal smoothly transition the change in the trace width, and slow down the impedance discontinuity. When the impedance discontinuity slows down, the phase change during signal transmission will also decrease, thereby reducing signal distortion and improving signal transmission quality.

[0062] Embodiment 4, please refer to Figure 6, the first differential signal line is, for example, a P signal line, and the second differential signal line is, for example, an N signal line. The left end of the first trace is connected to the first transmission line. The angle between the left end of the second trace A and the horizontal direction is α. The first trace, the second trace A, the third trace C, the fourth trace B, and the fifth trace are connected in sequence. The second differential signal line includes a sixth trace, and the sixth left line is disposed at the middle position of the differential phase matching structure. The distance between the first trace and the second differential signal line is a first distance S, the distance between the fifth trace and the second differential signal line is the first distance S, and the distance between the third trace and the sixth trace is a second distance H. The trace length of the second trace A is equal to that of the fourth trace B, and the line width varies. The angle α varies in the range of 45° to 90°. The trace length of the third trace is L1, the trace line width is c1, the trace length of the sixth trace is L2, and the trace line width is d1. The variation range of the second distance H is between twice the first distance S and six times the first distance S, that is, [2S, 6S]. The trace length L1 of the third trace is between 2w and 10w, that is, [2w, 10w]. The trace length of the sixth trace is between 2w and 15w, that is, [2w, 15w]. The line width c1 of the third trace is between w and 2w, that is, [w, 2w]. The line width d1 of the sixth trace is between w and 2w, that is, [w, 2w].

[0063] Specifically, when the differential signal line passes through a corner or the trace width changes, impedance mutation will occur, resulting in signal reflection and transmission loss. Even if the line widths of the bulge A section and the B section remain unchanged, by adjusting the line widths of the C section and the D section, the characteristic impedance of the trace can be changed to match the impedance of the adjacent trace at the corner or width change. When the impedances of the C section and the D section match the impedance of the adjacent trace, the impedance mutation can be effectively reduced, thereby reducing signal reflection and transmission loss and improving signal transmission quality. At the same time, by adjusting the line widths of the C section and the D section, the change in the trace width can be smoothly transitioned, and the impedance discontinuity can be alleviated. When the impedance discontinuity is alleviated, the phase change during signal transmission will also be reduced, thereby reducing signal distortion and improving signal transmission quality.

[0064] Embodiment Five, please refer to Figure 7, the first differential signal line is, for example, a P signal line, and the second differential signal line is, for example, an N signal line. The left end of the first trace is connected to the first transmission line. The included angle between the left end of the second trace A and the horizontal direction is α. The first trace, the second trace A, the third trace C, the fourth trace B, and the fifth trace are connected in sequence. The second differential signal line includes a sixth trace, and the sixth left line is disposed at the middle position of the differential phase matching structure. The distance between the first trace and the second differential signal line is a first distance S. The distance between the fifth trace and the second differential signal line is the first distance S. The distance between the third trace and the sixth trace is a second distance H. The trace length of the second trace A is equal to the trace length of the fourth trace B. The line width of the second trace is a1, and the trace width of the fourth trace is b1. The trace length of the third trace is L1, and the line width of the trace is c1. The trace length of the sixth trace is L2, and the trace width is d1. The variation range of the second distance H is between twice the first distance S and six times the first distance S, that is, [2S, 6S]. The trace length L1 of the third trace is between 2w and 10w, that is, [2w, 10w]. The trace length of the sixth trace is between 2w and 15w, that is, [2w, 15w]. The range of the line width a1 of the second trace is between w and 2w, that is, [w, 2w]. The line width b1 of the fourth trace is between w and 2w, that is, [w, 2w]. The line width c1 of the third trace is between w and 2w, that is, [w, 2w]. The line width d1 of the sixth trace is between w and 2w, that is, [w, 2w].

[0065] Specifically, when the differential signal line passes through a corner or the trace width changes, impedance mutation will occur, resulting in signal reflection and transmission loss. By adjusting the line widths of the traces in sections A, B, C, and D, the characteristic impedance of the traces can be changed to match the impedance of the adjacent traces at the corner or width change. When the impedances of the traces in sections A, B, C, and D match the impedance of the adjacent traces, the impedance mutation can be effectively reduced, thereby reducing signal reflection and transmission loss and improving signal transmission quality. At the same time, by adjusting the line widths of the traces in sections A, B, C, and D, the change in the trace width can be smoothly transitioned, making the impedance discontinuity less abrupt. When the impedance discontinuity becomes less abrupt, the phase change during signal transmission will also decrease, thereby reducing signal distortion and improving signal transmission quality.

[0066] In summary, Embodiment 1 and Embodiment 2 focus on length matching and line width adjustment of differential traces, and are applicable to the situation where the length difference of differential traces is small, and phase mismatch mainly needs to be compensated by length and line width adjustment. By adjusting the path and shape of the trace, such as adding a bulge structure or changing the trace path, to ensure that the lengths of differential traces are as equal as possible, thereby reducing the phase difference. By changing the width of the trace, the characteristic impedance of the trace can be changed, thereby compensating for the phase mismatch caused by the length difference of the traces. Embodiment 3 and Embodiment 4 add spacing adjustment on the basis of Embodiment 1 and Embodiment 2, and are applicable to the situation where the length difference of differential traces is large, or more precise control of phase matching is required. By changing the spacing between differential traces, the coupling degree of the traces can be changed, thereby further compensating for phase mismatch. Increasing the spacing can reduce the coupling, while decreasing the spacing can increase the coupling. Embodiment 5 further optimizes the trace shape on the basis of Embodiment 3 and Embodiment 4, and is applicable to scenarios with very high requirements for differential phase matching, such as high-frequency signal transmission or high-speed digital circuit design. By changing the shape of the trace, such as using curved or inclined traces, the electrical length of the trace can be changed, thereby more precisely compensating for phase mismatch.

[0067] In summary, the differential phase matching structure provided in this application not only realizes impedance adjustment between differential signal lines through a bulge structure, but also corrects the problem that the existing bulge structure will increase the line spacing between differential signal lines while increasing the impedance of the signal lines, resulting in phase mismatch between signal lines, and extends five optimized differential phase matching structures. The bulge structure will increase the impedance between PN differential lines. Through these five structures, the line width on the first signal line and / or the second signal line can be increased, and the change in the line spacing between differential signals can be resisted through this structure. While setting the bulge structure, the line width of the differential line is adjusted to make up for the impedance change caused by the increase in line spacing. According to the change in the line spacing of the differential traces inside the PCB, the optimized structure can be arbitrarily selected for differential phase adjustment. The optimized structure can either select to optimize the line width of the differential trace or optimize the line spacing of the differential trace. By setting the adjustment ratios of the line width, line spacing, and line length, the differential phase mismatch caused by the impedance change of the bulge structure is corrected, realizing phase matching between the sending end and the receiving end, and improving the signal transmission quality.

[0068] As Figure 8 shown, this application also provides a communication system. The communication system 1 includes a sending end 11, a receiving end 12, a differential phase matching structure 13, and a differential channel 14; the sending end 11 and the receiving end 12 are arranged at both ends of the differential channel 14; the differential phase matching structure 13 is connected to the differential channel 14. The differential phase matching structure 13 is arranged on one side of the sending end 11, and / or on one side of the receiving end 12, and / or at the middle position of the differential channel 14.

[0069] The descriptions of the processes or structures corresponding to the above respective drawings each have their own focuses. For the parts not detailed in a certain process or structure, reference may be made to the relevant descriptions of other processes or structures.

[0070] The above embodiments are only illustrative of the principles and effects of the present application, rather than being 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 differential phase matching structure, characterized in that: The differential phase matching structure is arranged on a differential channel of a PCB board, and includes a first differential signal line and a second differential signal line, wherein the first differential signal line and the second differential signal line form a bulge structure for matching the phase on the differential channel; The differential channel includes a first transmission line and a second transmission line; the first differential signal line is composed of a first routing line, a second routing line, a third routing line, a fourth routing line, and a fifth routing line, the left end of the first routing line is connected to the first section of the first transmission line, and the right end of the fifth routing line is connected to the second section of the first transmission line; the left end of the second differential signal line is connected to the first section of the second transmission line, and the right end of the second differential signal line is connected to the second section of the second transmission line; The spacing between the first routing line and the second differential signal line is equal to the spacing between the fifth routing line and the second differential signal line; the spacing between the first routing line and the second differential signal line is a first spacing; the spacing between the third routing line and the second differential signal line is a second spacing; the second spacing is greater than the first spacing; the first spacing and the second spacing are used to adjust the phase of the differential channel.

2. The differential phase matching structure according to claim 1, characterized in that: The second differential signal line further includes a sixth line, and the sixth line is located in the middle of the second differential signal line. The center position of the sixth line corresponds to the center position of the third line in an up-and-down relationship.

3. The differential phase matching structure according to claim 2, characterized in that: The line width of the sixth routing is equal to the line width of the third routing; the line length of the sixth routing is N times the line width of the first differential signal line, and the line width of the sixth routing is M times the line width of the first differential signal line, which is used to compensate for the phase of the differential signal line, wherein the value range of N and M is greater than 0.

4. The differential phase matching structure according to claim 2, characterized in that: The minimum line length of the sixth line is equal to the minimum line length of the third line.

5. The differential phase matching structure according to claim 1, characterized in that: The second spacing is K times the first spacing and is used to adjust the phase of the differential signal line.

6. The differential phase matching structure according to claim 5, characterized in that: The minimum spacing of the second spacing is twice the first spacing; the maximum spacing of the second spacing is six times the first spacing.

7. The differential phase matching structure according to claim 1, characterized in that: The angle between the second routing line and the horizontal direction is in the range of 45° to 90°; the second routing line and the fourth routing line are symmetrical with respect to the third routing line, and the third routing line is parallel to the horizontal direction.

8. The differential phase matching structure according to claim 1, characterized in that: The line width of the first routing line is equal to the line width of the fifth routing line; the line width of the second routing line is equal to the line width of the fourth routing line.

9. The differential phase matching structure according to claim 1, characterized in that: The line width of the first transmission line is equal to the line width of the second transmission line; the minimum line length of the third line is twice the line width of the first transmission line; and the maximum line length of the third line is ten times the line width of the first transmission line.

10. A communication system, characterized in that: The communication system includes a transmitting end, a receiving end, a differential channel, and a differential phase matching structure; the transmitting end and the receiving end are arranged at two ends of the differential channel; the differential phase matching structure is connected to the differential channel, and is arranged on one side of the transmitting end, and / or one side of the receiving end, and / or in the middle of the differential channel.

Images