Circuit board

Abstract

The utility model discloses a circuit board which comprises a first differential line pair composed of a first signal line and a second signal line which are insulated from each other, and the first signal line comprises a plurality of first transmission line segments which are arranged at intervals and first connecting line segments which are used for connecting two adjacent first transmission line segments. The second signal line comprises a plurality of second transmission line sections arranged at intervals and second connecting line sections used for connecting two adjacent second transmission line sections, the first transmission line sections and the second transmission line sections are in one-to-one correspondence and are arranged in parallel relatively, and the first connecting line sections and the second connecting line sections are in one-to-one correspondence and are arranged in parallel relatively. And the projections of the first connecting line segments and the corresponding second connecting line segments on the plane of the circuit board are crossed, and an interference magnetic field of an external interference signal generates induction currents with the same size and opposite directions on the two sides of the intersection point of the same signal line, so that the interference of the external signal is counteracted, and the signal transmission quality is improved.

Description

Technical Field

[0001] The utility model relates to a transmission signal line technology, in particular to a circuit board. Background Art

[0002] Differential transmission is a signal transmission technology. Different from the traditional method of one signal line and one ground line, differential transmission transmits signals on both lines. The two signals have the same amplitude and opposite phase. The signal transmitted on these two lines is a differential signal.

[0003] The existing differential line structure has the problem of poor anti-interference ability, which affects the signal transmission quality. Utility Model Content

[0004] The utility model provides a circuit board and a flexible circuit board, which can offset the interference of external signals and improve the signal transmission quality.

[0005] In a first aspect, an embodiment of the utility model provides a circuit board, comprising a first differential line pair consisting of a first signal line and a second signal line insulated from each other;

[0006] The first signal line includes a plurality of first transmission line segments arranged at intervals and a first connecting line segment for connecting two adjacent first transmission line segments;

[0007] The second signal line includes a plurality of second transmission line segments arranged at intervals and a second connecting line segment for connecting two adjacent second transmission line segments;

[0008] The first transmission line segment corresponds to the second transmission line segment one by one and is arranged relatively parallel;

[0009] The first connecting line segments correspond to the second connecting line segments one by one, and the projections of the first connecting line segments and the corresponding second connecting line segments on the plane of the circuit board intersect.

[0010] Optionally, the circuit board includes two circuit layers, two adjacent first transmission line segments are respectively arranged in the two circuit layers, two adjacent second transmission line segments are respectively arranged in the two circuit layers, and the opposite first transmission line segments and second transmission line segments are respectively arranged in the two circuit layers.

[0011] Optionally, the circuit board includes two first composite layers and a first liner layer disposed between the two first composite layers, and the first composite layer includes a first insulating substrate, the circuit layer disposed on the first insulating substrate, and a first protective film covering the circuit layer;

[0012] The first connecting line segment and the second connecting line segment are both connecting vias, and the connecting vias penetrate the first liner layer.

[0013] Optionally, the circuit board includes two circuit layers, the first signal line is arranged in one of the circuit layers, and the second signal line is arranged in the other circuit layer.

[0014] Optionally, the circuit board includes two first composite layers and a first liner layer arranged between the two first composite layers, and the first composite layer includes a first insulating substrate, the circuit layer arranged on the first insulating substrate, and a first protective film covering the circuit layer.

[0015] Optionally, the first gasket layer includes a plurality of first gasket blocks arranged at intervals, and two adjacent first gasket blocks form a first cavity between the first transmission line segment and the second transmission line segment that are opposite to each other.

[0016] Optionally, the circuit board also includes two second composite layers and two second padding layers, the two first composite layers are arranged between the two second composite layers, the second padding layer is arranged between the second composite layer and the adjacent first composite layer, and the second composite layer includes a second insulating substrate, a grounding layer arranged on the second insulating substrate, and a second protective film covering the grounding layer.

[0017] Optionally, the second cushion layer includes a plurality of second cushion blocks arranged at intervals, a second cavity is formed between two adjacent second cushion blocks, and the first cavity is arranged opposite to the second cavity.

[0018] Optionally, the circuit board further includes a plurality of ground vias, wherein the ground vias penetrate the first pad layer and the second pad layer to connect the ground layers in the two second composite layers, and the ground vias are insulated from the first signal line and the second signal line.

[0019] Optionally, the circuit board further includes a second differential line pair, the second differential line pair includes two parallel differential lines, and the differential lines are parallel to the first transmission line segment in the circuit board.

[0020] Optionally, the circuit board includes two parallel first differential line pairs, and the intersection of the two first differential line pairs is staggered in a direction perpendicular to the extension direction of the first differential line pairs.

[0021] Optionally, a projection of the intersection of one of the first differential line pairs on another of the first differential line pairs is located at a midpoint of a first transmission line segment or a second transmission line segment of another of the first differential line pairs.

[0022] The utility model provides a circuit board, comprising a first differential line pair consisting of a mutually insulated first signal line and a second signal line, wherein the first signal line comprises a first transmission line segment arranged at multiple intervals and a first connecting line segment used to connect two adjacent first transmission line segments, and the second signal line comprises a second transmission line segment arranged at multiple intervals and a second connecting line segment used to connect two adjacent second transmission line segments, the first transmission line segment corresponds to the second transmission line segment one-to-one and is arranged relatively parallel, the first connecting line segment corresponds to the second connecting line segment one-to-one, and the projections of the first connecting line segment and the corresponding second connecting line segment on the plane of the circuit board intersect, and the interference magnetic field of the external interference signal generates induced currents of the same magnitude and opposite directions on both sides of the intersection of the same signal line, thereby offsetting the interference of the external signal and improving the signal transmission quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The utility model is further described in detail below based on the drawings and embodiments.

[0024] Figure 1 A top perspective view of a circuit board provided by an embodiment of the utility model;

[0025] Figure 2 A schematic diagram of the principle of shielding external interference by the hinge differential pair structure provided in an embodiment of the utility model;

[0026] Figure 3 A schematic diagram of the structure of a differential line pair provided in an embodiment of the utility model;

[0027] Figure 4 A side perspective view of a circuit board provided by an embodiment of the utility model;

[0028] Figure 5 A schematic diagram of the structure of another differential line pair provided in an embodiment of the utility model;

[0029] Figure 6 A side perspective view of another circuit board provided by an embodiment of the utility model;

[0030] Figure 7 A top perspective view of another circuit board provided by an embodiment of the utility model;

[0031] Figure 8 A top perspective view of another circuit board provided by an embodiment of the utility model;

[0032] Fig. 9 It is a schematic diagram of interference when the intersection of two first differential line pairs is not misaligned;

[0033] Fig.10 The diagram is a schematic diagram of shielding interference when the intersections of two first differential line pairs are staggered. DETAILED DESCRIPTION

[0034] In order to make the technical problems solved by the utility model, the technical solutions adopted and the technical effects achieved clearer, the technical solutions of the embodiments of the utility model will be further described in detail below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the utility model.

[0035] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0036] In the present utility model, unless otherwise clearly stipulated and limited, the first feature being "above" or "below" the second feature may include the first and second features being in direct contact, or may include the first and second features not being in direct contact but being in contact through another feature between them. Moreover, the first feature being "above", "above" and "above" the second feature includes the first feature being directly above and obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. The first feature being "below", "below" and "below" the second feature includes the first feature being directly below and obliquely below the second feature, or simply means that the first feature is lower in level than the second feature. In addition, the terms "first" and "second" are only used to distinguish in description and have no special meaning.

[0037] Figure 1 A top perspective view of a circuit board provided by an embodiment of the utility model, such as Figure 1 As shown, a differential line pair consisting of a first signal line Line1 and a second signal line Line2 which are insulated from each other is referred to as a first differential line pair.

[0038] The first signal line Line1 includes a plurality of first transmission line segments 11 arranged at intervals and a first connecting line segment 12 for connecting two adjacent first transmission line segments 11 .

[0039] The second signal line Line2 includes a plurality of second transmission line segments 21 arranged at intervals and a second connecting line segment 22 for connecting two adjacent second transmission line segments 21 .

[0040] The first transmission line segment 11 corresponds to the second transmission line segment 21 one by one and is arranged relatively parallel. Figure 1 As shown, each first transmission line segment 11 can extend in the same direction, and each second transmission line segment 21 can extend in the same direction. In other embodiments of the utility model, each first transmission line segment 11 may not extend in the same direction, and each second transmission line segment 21 may not extend in the same direction. It is only necessary to keep the second transmission line segment 21 corresponding to the first transmission line segment 11 parallel, and the embodiments of the utility model are not limited here.

[0041] The first connecting line segments 12 correspond to the second connecting line segments 22 one by one, and the projections of the first connecting line segments 12 and the corresponding second connecting line segments 22 on the plane of the circuit board intersect (the intersection is insulated).

[0042] In this way, the first signal line Line1 and the second signal line Line2 form a hinge differential pair structure, and the hinge differential pair structure can better shield the interference of external signals and improve signal quality. Figure 2 The schematic diagram of the principle of shielding external interference by the hinge differential pair structure provided in the embodiment of the utility model is as follows: Figure 2 As shown, taking the interference magnetic field generated by the external interference signal between the first signal line Line1 and the second signal line Line2 as an example, the direction of the magnetic flux lines points outside the paper. When the interference signal increases, the magnetic field corresponding to the interference signal increases, the magnetic flux between the first signal line Line1 and the second signal line Line2 increases, and the first signal line Line1 on the right side of the intersection induces a rightward current i 1 , generating an induced magnetic field pointing into the paper, preventing the increase of magnetic flux, and the first signal line Line1 on the left side of the intersection induces a leftward current -i 1 , generating an induced magnetic field pointing into the paper, preventing the magnetic flux from increasing, and the current i 1 and current-i 1 The two signals cancel each other out, thus canceling out the interference of external signals. Similarly, the second signal line Line2 located on the right side of the intersection induces a leftward current -i 2 , generating an induced magnetic field pointing into the paper, preventing the increase of magnetic flux, and the second signal line Line2 located on the left side of the intersection induces a current i to the right 2 , generating an induced magnetic field pointing into the paper, preventing the magnetic flux from increasing, and the current i 2 and current-i 2 The interference of external signals is cancelled out by canceling each other. The magnetic flux lines of the interference magnetic field generated by the external interference signal between the first signal line Line1 and the second signal line Line2 point to the inside of the paper, which is similar to the case, and the embodiments of the utility model are not repeated here.

[0043] The circuit board provided by the embodiment of the utility model comprises a first differential line pair consisting of a first signal line and a second signal line insulated from each other, the first signal line comprises a first transmission line segment arranged at multiple intervals and a first connecting line segment for connecting two adjacent first transmission line segments, the second signal line comprises a second transmission line segment arranged at multiple intervals and a second connecting line segment for connecting two adjacent second transmission line segments, the first transmission line segment corresponds to the second transmission line segment one-to-one and is arranged relatively parallel, the first connecting line segment corresponds to the second connecting line segment one-to-one, and the projections of the first connecting line segment and the corresponding second connecting line segment on the plane of the circuit board intersect, the interference magnetic field of the external interference signal generates induced currents of the same magnitude and opposite directions on both sides of the intersection of the same signal line, thereby offsetting the interference of the external signal and improving the signal transmission quality.

[0044] In some embodiments of the present invention, the circuit board includes two circuit layers, two adjacent first transmission line segments are respectively arranged in the two circuit layers, two adjacent second transmission line segments are respectively arranged in the two circuit layers, and the opposite first transmission line segments and second transmission line segments are respectively arranged in the two circuit layers.

[0045] For example, Figure 3 A schematic diagram of a differential line pair structure provided by an embodiment of the utility model is shown in FIG. Figure 3 As shown, the circuit board includes two circuit layers, namely Layer 1 and Layer 2. One of two adjacent first transmission line segments 11 is located in the circuit layer Layer 1, and the other is located in the circuit layer Layer 2. The two first transmission line segments 11 are connected by a first connecting line segment 12. One of two adjacent second transmission line segments 21 is located in the circuit layer Layer 2, and the other is located in the circuit layer Layer 1. The two second transmission line segments 21 are connected by a second connecting line segment 22. The first transmission line segments 11 and the second transmission line segments 21 opposite to each other are respectively arranged in the two circuit layers Layer 1 and Layer 2. The projections of the first connecting line segments 12 and the second connecting line segments 22 opposite to each other on the circuit board plane intersect.

[0046] Figure 4 A side perspective view of a circuit board provided by an embodiment of the utility model, such as Figure 4 As shown, the circuit board includes two first composite layers CL1 and a first pad layer PL1 disposed between the two first composite layers CL1, and the first composite layer CL1 includes a first insulating substrate Sub1, a circuit layer (Layer1 or Layer2) disposed on the first insulating substrate Sub1, and a first protective film Coat1 covering the circuit layer. Exemplarily, the first insulating substrate Sub1 can be a flexible material, for example, so that a flexible circuit board can be prepared.

[0047] The first connecting line segment 12 and the second connecting line segment 22 are both connecting vias, and the connecting vias penetrate the first pad layer Sub1.

[0048] For example, in some embodiments of the present invention, Figure 4 As shown, the first pad layer PL1 includes a plurality of first pad blocks PAD1 arranged at intervals, and two adjacent first pad blocks PAD1 form a first cavity AG1 between the first transmission line segment 11 and the second transmission line segment 21. In this way, a flexible circuit board including a plurality of first cavities AG1 is formed, and the plurality of first cavities AG1 can increase the number of times the flexible circuit board can be bent and improve the bending performance. The first connecting line segment 12 and the second connecting line segment 22 penetrate the first pad block PAD1 and connect the circuit layers Layer1 and Layer2.

[0049] In some embodiments of the present invention, Figure 4 As shown, the circuit board also includes two second composite layers CL2 and two second pad layers PL2, the two first composite layers CL1 are arranged between the two second composite layers CL2, the second pad layer PL2 is arranged between the second composite layer CL2 and the adjacent first composite layer CL1, and the second composite layer CL2 includes a second insulating substrate Sub2, a ground layer GL arranged on the second insulating substrate Sub2, and a second protective film Coat2 covering the ground layer GL. The ground layers are arranged on both sides of the differential line pair to better shield the interference of external signals and further improve the signal transmission quality.

[0050] In some embodiments of the present invention, Figure 4 As shown, the second pad layer PL2 includes a plurality of second pad blocks PAD2 arranged at intervals, a second cavity AG2 is formed between two adjacent second pad blocks PAD2, and the first cavity AG1 and the second cavity AG2 are arranged opposite to each other. In this way, the number of bends and the bendability of the circuit board can be improved.

[0051] In some embodiments of the present invention, in order to improve the number of bends and the bending performance of the ground layer, the ground layer can also be designed in segments. For example, each grounding segment just corresponds to the position of the second cavity AG2.

[0052] In some embodiments of the present invention, Figure 4As shown, the circuit board also includes a plurality of ground vias GH. For example, a ground via GH is provided at each first pad block PAD1. The ground via GH penetrates the first pad layer (i.e., the first pad block PAD1) and the second pad layer (i.e., the second pad block PAD2), connects the ground layers GL in the two second composite layers, and the ground via GH is insulated from the first signal line Line1 and the second signal line Line2. The two ground layers GL are connected through a plurality of ground vias GH, which can improve the level consistency of the two ground layers GL.

[0053] Figure 5 A schematic diagram of the structure of another differential line pair provided by an embodiment of the utility model is shown as follows: Figure 5 As shown, the circuit board includes two circuit layers, namely Layer1 and Layer2. The first signal line Line1 is set in one of the circuit layers Layer1, and the second signal line Line2 is set in the other circuit layer Layer2, that is, the same signal line no longer penetrates different layers through vias. The projections of the first connecting line segment 12 and the second connecting line segment 22 on the plane of the circuit board intersect. The projections of the first transmission line segment 11 and the second transmission line segment 21 on the plane of the circuit board are parallel and the distance is D. Such a design does not require vias, which can reduce the manufacturing cost. In addition, the length of the connecting line segment along the extension direction of the transmission line segment can be shortened, thereby adapting to higher frequency differential signals.

[0054] Figure 6 A side perspective view of another circuit board provided by an embodiment of the utility model, such as Figure 6 As shown, the circuit board includes two first composite layers CL1 and a first pad layer PL1 disposed between the two first composite layers CL1, and the first composite layer CL1 includes a first insulating substrate Sub1, a circuit layer (Layer1 or Layer2) disposed on the first insulating substrate Sub1, and a first protective film Coat1 covering the circuit layer. Exemplarily, the first insulating substrate Sub1 can be a flexible material, for example, a flexible circuit board can be prepared in this way. The first signal line Line1 is disposed in one of the circuit layers Layer1, and the second signal line Line2 is disposed in another circuit layer Layer2.

[0055] For example, in some embodiments of the present invention, Figure 6 As shown, the first pad layer PL1 includes a plurality of first pad blocks PAD1 arranged at intervals, and two adjacent first pad blocks PAD1 form a first cavity AG1 between the first transmission line segment 11 and the second transmission line segment 21. In this way, a flexible circuit board including a plurality of first cavities AG1 is formed, and the plurality of first cavities AG1 can increase the number of bends of the flexible circuit board and improve the bending performance.

[0056] In some embodiments of the present invention, Figure 6 As shown, the circuit board also includes two second composite layers CL2 and two second pad layers PL2, the two first composite layers CL1 are arranged between the two second composite layers CL2, the second pad layer PL2 is arranged between the second composite layer CL2 and the adjacent first composite layer CL1, and the second composite layer CL2 includes a second insulating substrate Sub2, a ground layer GL arranged on the second insulating substrate Sub2, and a second protective film Coat2 covering the ground layer GL. The ground layers are arranged on both sides of the differential line pair to better shield the interference of external signals and further improve the signal transmission quality.

[0057] In some embodiments of the present invention, Figure 6 As shown, the second pad layer PL2 includes a plurality of second pad blocks PAD2 arranged at intervals, a second cavity AG2 is formed between two adjacent second pad blocks PAD2, and the first cavity AG1 and the second cavity AG2 are arranged opposite to each other. In this way, the number of bends and the bendability of the circuit board can be improved.

[0058] In some embodiments of the present invention, in order to improve the number of bends and the bending performance of the ground layer, the ground layer can also be designed in segments. For example, each grounding segment just corresponds to the position of the second cavity AG2.

[0059] In some embodiments of the present invention, Figure 6 As shown, the circuit board also includes a plurality of ground vias GH. For example, a ground via GH is provided at every other first pad block PAD1. The ground via GH penetrates the first pad layer (i.e., the first pad block PAD1) and the second pad layer (i.e., the second pad block PAD2), connects the ground layers GL in the two second composite layers, and the ground via GH is insulated from the first signal line Line1 and the second signal line Line2. The two ground layers GL are connected through a plurality of ground vias GH, which can improve the level consistency of the two ground layers GL.

[0060] Figure 7 A top perspective view of another circuit board provided by an embodiment of the utility model, such as Figure 7 As shown, the circuit board also includes a second differential line pair, which includes two parallel differential lines Line3 and Line4, and the differential lines are parallel to the first transmission line segment 11 in the circuit board. The two lines of the second differential line pair can be respectively set in different circuit layers, or can be set in the same circuit layer, which is not limited in the embodiment of the utility model. Other structures in this embodiment are similar to the above-mentioned embodiment, and the embodiment of the utility model will not be repeated here.

[0061] Figure 8 A top perspective view of another circuit board provided by an embodiment of the utility model, such as Figure 8As shown, the circuit board includes two parallel first differential line pairs, and the intersection of the two first differential line pairs is staggered in a direction perpendicular to the extension direction of the first differential line pairs, that is, the intersection of the two first differential line pairs is not directly opposite. Fig. 9 This is a schematic diagram of interference when the intersection of the two first differential line pairs is not separated. Fig.10 This is a schematic diagram of shielding interference when the intersections of the two first differential line pairs are staggered, as shown in FIG. Fig. 9 As shown, the positive direction of the current is defined as the right direction, and the current of Line 3 is i 1 , the current of Line 4 is -i 1 For example, the current i of Line 3 1 A magnetic field is generated below, with magnetic flux lines pointing to the inside of the paper. The current in Line 4 is -i 1 A magnetic field with magnetic flux lines pointing outside the paper is generated below. When the current i 1 and -i 1 When the current increases, the magnetic field generated by Line 3 on the right side of the intersection increases, and the part of Line 2 on the right side of the intersection induces a leftward current -i 2 , generating an induced magnetic field pointing out of the paper, preventing the increase of magnetic flux, and the magnetic field generated by Line 4 on the left side of the intersection increases, and the part of Line 2 on the left side of the intersection induces a leftward current -i 2 , generating an induced magnetic field pointing into the paper, preventing the increase of magnetic flux. The two currents have the same magnitude and direction, which amplifies the interference between the differential line pairs. Similarly, Line 1 will also generate an induced current of the same magnitude and direction.

[0062] like Fig.10 As shown, the intersection of the two first differential line pairs is staggered in a direction perpendicular to the extension direction of the first differential line pairs, and the direction pointing to the right is defined as the positive direction of the current. The current of Line 3 is i 1 , the current of Line 4 is -i 1 For example, the current i of Line 3 on the left side of the intersection of Line 3 and Line 4 is 1 A magnetic field is generated below, with magnetic flux lines pointing to the inside of the paper. The current in Line 4 on the right side of the intersection of Line 3 and Line 4 is -i 1 A magnetic field with magnetic flux lines pointing outside the paper is generated below. When the current i 1 and -i 1 When the magnetic field generated by Line 3 increases, the part of Line 2 on the left side of the intersection induces a leftward current -i 2 , generating an induced magnetic field pointing out of the paper, preventing the increase of magnetic flux, the magnetic field generated by Line 4 increases, and the part of Line 2 located to the right of the intersection induces a current i to the right 2, generating an induced magnetic field pointing into the paper, preventing the increase of magnetic flux. The two currents are equal in magnitude and opposite in direction, canceling each other out, thus canceling out the interference between the differential line pairs. Similarly, Line 1 will also generate an induced current of the same magnitude and opposite in direction.

[0063] For example, in the above embodiment, Figure 8 As shown, the projection of the intersection of one of the first differential line pairs on the other first differential line pair is located at the midpoint of the first transmission line segment or the second transmission line segment of the other first differential line pair.

[0064] In the description of this article, it is necessary to understand that the terms "up", "down", "left", "right", and other orientations or positional relationships are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of description and simplification of operation, 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 therefore cannot be understood as a limitation on the present invention.

[0065] In the description of this specification, the description with reference to the terms "an embodiment", "example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example.

[0066] In addition, it should be understood that although this specification is described according to implementation methods, not every implementation method contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

[0067] The technical principle of the present invention is described above in combination with specific embodiments. These descriptions are only for explaining the principle of the present invention and cannot be interpreted as limiting the protection scope of the present invention in any way. Based on the explanations here, technicians in this field can think of other specific implementation methods of the present invention without creative work, and these methods will fall within the protection scope of the present invention.

Claims

1. A circuit board, characterized in that: A first differential line pair including a first signal line and a second signal line insulated from each other; The first signal line includes a plurality of first transmission line segments arranged at intervals and a first connecting line segment for connecting two adjacent first transmission line segments; The second signal line includes a plurality of second transmission line segments arranged at intervals and a second connecting line segment for connecting two adjacent second transmission line segments; The first transmission line segment corresponds to the second transmission line segment one by one and is arranged relatively parallel; The first connecting line segments correspond to the second connecting line segments one by one, and the projections of the first connecting line segments and the corresponding second connecting line segments on the plane of the circuit board intersect.

2. The circuit board according to claim 1, characterized in that: The circuit board includes two circuit layers, two adjacent first transmission line segments are respectively arranged in the two circuit layers, two adjacent second transmission line segments are respectively arranged in the two circuit layers, and the opposite first transmission line segments and second transmission line segments are respectively arranged in the two circuit layers.

3. The circuit board according to claim 2, characterized in that: The circuit board comprises two first composite layers and a first liner layer arranged between the two first composite layers, wherein the first composite layer comprises a first insulating substrate, the circuit layer arranged on the first insulating substrate and a first protective film covering the circuit layer; The first connecting line segment and the second connecting line segment are both connecting vias, and the connecting vias penetrate the first liner layer.

4. The circuit board according to claim 1, characterized in that: The circuit board includes two circuit layers, the first signal line is arranged in one of the circuit layers, and the second signal line is arranged in the other circuit layer.

5. The circuit board according to claim 4, characterized in that: The circuit board includes two first composite layers and a first liner layer arranged between the two first composite layers. The first composite layer includes a first insulating substrate, the circuit layer arranged on the first insulating substrate, and a first protective film covering the circuit layer.

6. The circuit board according to claim 3 or 5, characterized in that: The first liner layer includes a plurality of first liner blocks arranged at intervals, and two adjacent first liner blocks form a first cavity between the first transmission line segment and the second transmission line segment that are opposite to each other.

7. The circuit board according to claim 6, characterized in that: The circuit board also includes two second composite layers and two second padding layers, the two first composite layers are arranged between the two second composite layers, the second padding layer is arranged between the second composite layer and the adjacent first composite layer, and the second composite layer includes a second insulating substrate, a grounding layer arranged on the second insulating substrate, and a second protective film covering the grounding layer.

8. The circuit board according to claim 7, characterized in that: The second cushion layer includes a plurality of second cushion blocks arranged at intervals, a second cavity is formed between two adjacent second cushion blocks, and the first cavity is arranged opposite to the second cavity.

9. The circuit board according to claim 7, characterized in that: The circuit board further includes a plurality of ground vias, wherein the ground vias penetrate the first pad layer and the second pad layer, connect the ground layers in the two second composite layers, and the ground vias are insulated from the first signal line and the second signal line.

10. The circuit board according to any one of claims 1 to 5, characterized in that: The circuit board further includes a second differential line pair, wherein the second differential line pair includes two parallel differential lines, and the differential lines are parallel to the first transmission line segment in the circuit board.

11. The circuit board according to any one of claims 1 to 5, characterized in that: The circuit board includes two parallel first differential line pairs, and the intersection of the two first differential line pairs is staggered in a direction perpendicular to the extension direction of the first differential line pairs.

12. The circuit board according to claim 11, characterized in that: A projection of the intersection of one of the first differential line pairs on another of the first differential line pairs is located at a midpoint of the first transmission line segment or the second transmission line segment of the other of the first differential line pairs.

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