Differential Crosstalk Noise Coupler, PCB Board and SerDes Test System

Abstract

The present disclosure relates to a differential crosstalk noise coupler, a PCB board and a SerDes test system, and relates to the field of integrated circuit testing technology. The differential crosstalk noise coupler includes: a victim line, including a first victim sub-line and a second victim sub-line, the first victim sub-line and the second victim sub-line are single-ended lines; an attack line, including a first attack sub-line and a second attack sub-line, the first attack sub-line and the first victim sub-line are coupled to form a first differential signal line pair, and the second attack sub-line and the second victim sub-line are coupled to form a second differential signal line pair. The technical solution disclosed in the present disclosure helps to maintain the impedance of the victim line basically unchanged, and will not affect the impedance of the victim line when a large noise is applied through the attack line. Therefore, it helps to test the crosstalk tolerance boundary of the victim line and helps to improve the reliability of the differential signal line crosstalk test.

Description

Technical Field

[0001] The present disclosure relates to the technical field of integrated circuit testing, and in particular to a differential crosstalk noise coupler, a PCB board and a SerDes (Serializer / Deserializer) testing system. Background Art

[0002] SI (Signal Integrity) testing in integrated circuits is a testing method to ensure that the signal in the electronic system maintains its integrity and quality during transmission. Since high-speed signals may be affected by noise, attenuation, distortion, reflection, crosstalk and other factors during transmission, which may cause signal quality to deteriorate and thus affect the performance of the entire system, SI testing is particularly important for high-speed electronic devices.

[0003] The crosstalk test of differential signal lines is an important test item in SI testing. This test introduces crosstalk through an aggressor line (also called an aggressor line) near the differential signal line that serves as the victim line and performs a crosstalk test. However, in the test method of arranging an aggressor line near the differential signal line, there is a large difference between the environment of the differential signal line and the environment of the differential signal line in the actual application circuit, which makes it difficult for the crosstalk test results to reflect the crosstalk situation of the differential signal line in the actual application circuit.

[0004] Therefore, the crosstalk test method of differential signal lines needs to be further improved. Summary of the invention

[0005] In view of this, the present disclosure provides a differential crosstalk noise coupler, a PCB board and a SerDes test system to help improve the result of differential signal line crosstalk test.

[0006] According to one aspect of an embodiment of the present disclosure, a differential crosstalk noise coupler is provided, comprising:

[0007] A victim line, wherein the victim line includes a first victim sub-line and a second victim sub-line, and the first victim sub-line and the second victim sub-line are single-ended lines;

[0008] An attack line, the attack line comprising a first attack sub-line and a second attack sub-line, the first attack sub-line and the first victim sub-line are coupled to form a first differential signal line pair, and the second attack sub-line and the second victim sub-line are coupled to form a second differential signal line pair;

[0009] A victim differential lead pair, the victim differential lead pair comprising a first victim sub-lead and a second victim sub-lead, wherein the first victim sub-lead is connected to the first victim sub-lead, and the second victim sub-lead is connected to the second victim sub-lead;

[0010] An attack differential lead pair, the attack differential lead pair comprising a first attack sub-lead and a second attack sub-lead, wherein the first attack sub-lead is connected to the first attack sub-line, and the second attack sub-lead is connected to the second attack sub-line;

[0011] The victim differential lead pair and the victim line are located on the same inner layer of the PCB board, and the attack differential lead pair and the attack line are located on different inner layers of the PCB board; or, the victim differential lead pair and the victim line are located on different inner layers of the PCB board, and the attack differential lead pair and the attack line are located on the same inner layer of the PCB board.

[0012] In a possible implementation manner, the first victim sub-line, the second victim sub-line, the first attack sub-line, and the second attack sub-line all extend in straight lines.

[0013] In a possible implementation manner, the victim line and the attack line are located in the same inner layer of the PCB board.

[0014] In a possible implementation manner, when the victim differential lead pair and the victim line are located in the same inner layer of the PCB board, and the attack differential lead pair and the attack line are located in different inner layers of the PCB board:

[0015] The victim differential lead pair is connected to the victim line through a victim transition line, and the victim transition line and the victim line are located on the same inner layer of the PCB board;

[0016] The attack differential lead pair is connected to the attack line through an attack transition through-hole and an attack transition line, wherein the attack transition line and the attack line are located on the same inner layer of the PCB board, and the attack transition line is connected to the attack line, and the attack transition through-hole is connected between the attack differential lead pair and the attack transition line.

[0017] In a possible implementation manner, when the victim differential lead pair and the victim line are located in different inner layers of the PCB board, and the attack differential lead pair and the attack line are located in the same inner layer of the PCB board:

[0018] The attack differential lead pair is connected to the attack line through an attack transition line, and the attack transition line and the attack line are located on the same inner layer of the PCB board;

[0019] The victim differential lead pair is connected to the victim line through a victim transition through-hole and a victim transition line, wherein the victim transition line and the victim line are located in the same inner layer of the PCB board, and the victim transition line is connected to the victim line, and the victim transition through-hole is connected between the victim differential lead pair and the victim transition line.

[0020] In a possible implementation, it further includes:

[0021] A victim line SMA interface, the victim line SMA interface is connected to the victim differential lead pair;

[0022] An attack line SMA interface, wherein the attack line SMA interface is connected to the attack differential lead pair.

[0023] In a possible implementation manner, the victim transition line includes a first victim transition sub-line and a second victim transition sub-line, the attack transition through-hole includes a first attack transition sub-through-hole and a second attack transition sub-through-hole, and the attack transition line includes a first attack transition sub-line and a second attack transition sub-line; wherein,

[0024] The first victim sub-lead is connected to the first victim sub-line through the first victim transition sub-line, the second victim sub-lead is connected to the second victim sub-line through the second victim transition sub-line, and the first victim transition sub-line and the second victim transition sub-line are located in the same inner layer of the PCB board as the victim line;

[0025] The first attack sub-lead is connected to the first attack sub-line through the first attack transition sub-through hole and the first attack transition sub-line, and the second attack sub-lead is connected to the second attack sub-line through the second attack transition sub-through hole and the second attack transition sub-line, wherein the first attack transition sub-line and the second attack transition sub-line are located in the same inner layer of the PCB board as the attack line, and the first attack transition sub-line is connected to the first attack sub-line, the second attack transition sub-line is connected to the second attack sub-line, the first attack transition sub-through hole is connected between the first attack sub-lead and the first attack transition sub-line, and the second attack transition sub-through hole is connected between the second attack sub-lead and the second attack transition sub-line.

[0026] In a possible implementation manner, the attack transition line includes a first attack transition sub-line and a second attack transition sub-line, the victim transition through-hole includes a first victim transition sub-through-hole and a second victim transition sub-through-hole, and the victim transition line includes a first victim transition sub-line and a second victim transition sub-line; wherein,

[0027] The first attack sub-lead is connected to the first attack sub-line through the first attack transition sub-line, the second attack sub-lead is connected to the second attack sub-line through the second attack transition sub-line, and the first attack transition sub-line and the second attack transition sub-line are located in the same inner layer of the PCB board as the attack line;

[0028] The first victim sub-lead is connected to the first victim sub-line through the first victim transition sub-through hole and the first victim transition sub-line, and the second victim sub-lead is connected to the second victim sub-line through the second victim transition sub-through hole and the second victim transition sub-line, wherein the first victim transition sub-line and the second victim transition sub-line are located in the same inner layer of the PCB board as the victim line, and the first victim transition sub-line is connected to the first victim sub-line, the second victim transition sub-line is connected to the second victim sub-line, the first victim transition sub-through hole is connected between the first victim sub-lead and the first victim transition sub-line, and the second victim transition sub-through hole is connected between the second victim sub-lead and the second victim transition sub-line.

[0029] According to another aspect of an embodiment of the present disclosure, a PCB board is provided, which adopts the differential crosstalk noise coupler as described in any one of the above items.

[0030] According to another aspect of an embodiment of the present disclosure, a SerDes test system is provided, which adopts the differential crosstalk noise coupler as described in any one of the above items.

[0031] It can be seen from the above scheme that in the differential crosstalk noise coupler, PCB board and SerDes test system of the embodiment of the present disclosure, since the first attack sub-line and the first victim sub-line are coupled to form a first differential signal line pair, and then from the perspective of the first victim sub-line, the first victim sub-line is still a single-ended line in a pair of differential signal lines, and there is only another single-ended line (the first attack sub-line) in the differential signal line (the first differential signal line pair) near the first victim sub-line. Under ideal circumstances, this structure will not cause a change in the parasitic capacitance of the first victim sub-line, and thus the impedance of the first victim sub-line will not change under ideal circumstances. Similarly, since the second attacking sub-line and the second victim sub-line are coupled to form a second differential signal line pair, from the perspective of the second victim sub-line, the second victim sub-line is still a single-ended line in a pair of differential signal lines, and there is only another single-ended line (the second attacking sub-line) in the differential signal line (the second differential signal line pair) near the second victim sub-line. This structure will not cause the parasitic capacitance of the second victim sub-line to change under ideal conditions, and the impedance of the second victim sub-line will not change under ideal conditions. Therefore, from the perspective of the victim line composed of the first victim sub-line and the second victim sub-line, the overall parasitic capacitance of the victim line does not change under ideal conditions, and the impedance does not change under ideal conditions. Therefore, compared with the related art, the differential crosstalk noise coupler, PCB board and SerDes test system disclosed in the present invention can help to maintain the impedance of the victim line basically unchanged, and will not affect the impedance of the victim line when a large noise is applied through the attack line. Therefore, the differential crosstalk noise coupler, PCB board and SerDes test system disclosed in the present invention can help to test the crosstalk tolerance boundary of the victim line, and help to improve the reliability of the differential signal line crosstalk test. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a schematic diagram of the wiring structure used in the related art for performing crosstalk testing on differential signal lines;

[0033] Figure 2 is a schematic structural diagram of a differential crosstalk noise coupler according to an exemplary embodiment;

[0034] Figure 3A yes Figure 2 A local structural diagram of a connection area between a victim differential lead pair, an attack differential lead pair, a victim line and an attack line;

[0035] Figure 3B yes Figure 2 A partial structural diagram of another connection area of ​​a victim differential lead pair, an aggressor differential lead pair, and a victim line and an aggressor line;

[0036] Figure 4is another structural schematic diagram of a differential crosstalk noise coupler according to an exemplary embodiment;

[0037] Figure 5A yes Figure 4 A local structural diagram of a connection area between a victim differential lead pair, an attack differential lead pair, a victim line and an attack line;

[0038] Figure 5B yes Figure 4 A partial structural diagram of another connection area of ​​a victim differential lead pair, an aggressor differential lead pair, and a victim line and an aggressor line;

[0039] Figure 6 is a schematic diagram of the overall structure of a differential crosstalk noise coupler according to an exemplary embodiment;

[0040] Figure 7 is a schematic diagram of a modeling structure of a simulation section in a differential crosstalk noise coupler according to an exemplary embodiment;

[0041] Figure 8 Yes Figure 7 Schematic diagram of impedance simulation curve of the structure shown;

[0042] Fig. 9 Yes Figure 7 Schematic diagram of the crosstalk simulation curve of the structure shown. DETAILED DESCRIPTION

[0043] In order to make the objectives, technical solutions and advantages of the present disclosure more clearly understood, the present disclosure is further described in detail below with reference to the accompanying drawings and examples.

[0044] It should be noted that the terms "first", "second", etc. in the specification and claims of the present disclosure and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence.

[0045] Figure 1 This is a schematic diagram of the wiring structure used in the related art for crosstalk testing of differential signal lines, such as Figure 1As shown, in the related art, when performing crosstalk test on differential signal lines, the attack line 2 is placed close to and parallel to the victim line 1 to couple noise into the victim line 1. In the related art, the distance between the attack line 2 and the victim line 1 is usually controlled to be 2 to 3 times the line width to couple noise. In this solution, if the coupling ability between the attack line 2 and the victim line 1 needs to be increased, the attack line 2 and the victim line 1 need to be as close as possible, for example, the distance between them is reduced to about 1 time the line width. However, although the coupling ability can be enhanced, this approach brings new problems. The proximity of the attack line 2 and the victim line 1 will increase the parasitic capacitance of the victim line 1. The closer the attack line 2 is to the victim line 1, the lower the impedance of the victim line 1. The reduction of the impedance of the victim line 1 will cause the problem of difficulty in distinguishing whether the bit error rate of the data transmitted in the victim line 1 is high due to noise or the test bit error rate of the data transmitted in the victim line 1 is high due to low impedance during the crosstalk test. It is impossible to decouple the contributions of the two to the SerDes test system, which also causes the problem of insufficient reliability of the test results. Therefore, the attack line 2 and the victim line 1 cannot be as close as possible, so the distance between the attack line 2 and the victim line 1 is usually controlled to be 2 to 3 times the line width. However, this method will make it impossible to add a large crosstalk into the SerDes test system, which will make it difficult to measure the crosstalk tolerance boundary of the victim line 1.

[0046] In view of this, the embodiments of the present disclosure provide a differential crosstalk noise coupler, a PCB board and a SerDes test system, so that the impedance of the victim line during the test is equivalent to the impedance of the differential signal line in the actual application circuit, and in this case, a larger crosstalk can be coupled from the attack line to the victim line, thereby helping the crosstalk test result of the victim line to be closer to its actual crosstalk tolerance boundary, so as to help improve the result of the differential signal line crosstalk test.

[0047] Figure 2 is a schematic diagram of a differential crosstalk noise coupler according to an exemplary embodiment. The differential crosstalk noise coupler of the embodiment of the present disclosure mainly includes a victim line 1 and an attack line 2. Specifically, Figure 2 As shown, the victim line 1 includes a first victim sub-line 101 and a second victim sub-line 102, and the first victim sub-line 101 and the second victim sub-line 102 are single-ended lines (that is, from the perspective of the victim line 1, the distance between the first victim sub-line 101 and the second victim sub-line 102 is increased, so that the first victim sub-line 101 and the second victim sub-line 102 each become a single-ended line), and the attack line 2 includes a first attack sub-line 201 and a second attack sub-line 202, and the first attack sub-line 201 and the first victim sub-line 101 are coupled to form a first differential signal line pair 11, and the second attack sub-line 202 and the second victim sub-line 102 are coupled to form a second differential signal line pair 21.

[0048] based on Figure 2 In the structure shown, from the perspective of the attack line 2, the distance between the first attack sub-line 201 and the second attack sub-line 202 is also increased, so that the first attack sub-line 201 and the second attack sub-line 202 are each also a single-ended line.

[0049] In the exemplary embodiment, noise is coupled from the attack line 2 to the victim line 1 . In the first differential signal line pair 11 , the first attack sub-line 201 couples noise to the first victim sub-line 101 . In the second differential signal line pair 21 , the second attack sub-line 202 couples noise to the second victim sub-line 102 .

[0050] In the differential crosstalk noise coupler of the embodiment of the present disclosure, since the first attacking sub-line 201 and the first victim sub-line 101 are coupled to form the first differential signal line pair 11, from the perspective of the first victim sub-line 101, the first victim sub-line 101 is still a single-ended line in a pair of differential signal lines, and there is only another single-ended line (the first attacking sub-line 201) in the differential signal line (the first differential signal line pair 11) near the first victim sub-line 101. Under ideal circumstances, this structure will not cause a change in the parasitic capacitance of the first victim sub-line 101, and thus the impedance of the first victim sub-line 101 will not change under ideal circumstances. Similarly, since the second attacking sub-line 202 and the second victim sub-line 102 are coupled to form the second differential signal line pair 21, from the perspective of the second victim sub-line 102, the second victim sub-line 102 is still a single-ended line in a pair of differential signal lines, and there is only another single-ended line (the second attacking sub-line 202) in the differential signal line (the second differential signal line pair 21) near the second victim sub-line 102. This structure will not cause the parasitic capacitance of the second victim sub-line 102 to change under ideal conditions, and the impedance of the second victim sub-line 102 will not change under ideal conditions. Therefore, from the perspective of the victim line 1 composed of the first victim sub-line 101 and the second victim sub-line 102, the overall parasitic capacitance of the victim line 1 does not change under ideal conditions, and the impedance does not change under ideal conditions. Therefore, compared with the related art, the differential crosstalk noise coupler of the embodiment of the present invention helps to maintain the impedance of the victim line 1 basically unchanged, and will not affect the impedance of the victim line 1 when a large noise is applied through the attack line 2. Therefore, when the differential crosstalk noise coupler of the embodiment of the present invention is applied to the SerDes test system, it helps to test the crosstalk tolerance boundary of the victim line 1, and helps to improve the reliability of the differential signal line crosstalk test.

[0051] Since the differential signal line will increase the parasitic capacitance due to other nearby wiring, resulting in the problem of reduced impedance, in order to avoid this problem as much as possible, in the exemplary embodiment, the distance between the first differential signal line pair 11 and the second differential signal line pair 21 is a distance that can ensure that the parasitic capacitance caused by the distance between the first differential signal line pair 11 and the second differential signal line pair 21 can be ignored.

[0052] In order to obtain a better crosstalk test result, it is necessary to ensure that the victim line 1 and the attack line 2 are equal in length, so that the crosstalk noise obtained by the first victim line 101 from the first attack line 201 can be related to the crosstalk noise obtained by the second victim line 102 from the second attack line 202. Based on this, in the exemplary embodiment, the first victim line 101, the second victim line 102, the first attack line 201 and the second attack line 202 are all extended in a straight line. The structure based on the straight line extension is helpful to strictly control the length design of the victim line 1 and the attack line 2.

[0053] like Figure 2 As shown, in order to simplify the differential crosstalk noise coupler and reduce the difficulty of design and manufacturing, in the exemplary embodiment, the victim line 1 and the attack line 2 are located on the same inner layer of the PCB board. In this way, it is easy to carry out targeted wiring design for the first victim sub-line 101, the second victim sub-line 102, the first attack sub-line 201 and the second attack sub-line 202 on the same inner layer of the PCB board.

[0054] In the differential crosstalk noise coupler of the disclosed embodiment, the first attacking sub-line 201 and the first victim sub-line 101 are coupled to form a first differential signal line pair 11, and the second attacking sub-line 202 and the second victim sub-line 102 are coupled to form a second differential signal line pair 21. However, from the perspective of the victim line 1, the first victim sub-line 101 and the second victim sub-line 102 are two single-ended lines in the victim line 1, and from the perspective of the attacking line 2, the first attacking sub-line 201 and the second attacking sub-line 202 are two single-ended lines in the attacking line 2. In circuit design, whether it is the victim line 1 or the attacking line 2, as differential signal lines, they need to appear in pairs and be routed, that is, the victim line 1 and the attacking line 2 each need to appear in pairs and be routed. Only in this way can the transmission of differential signals be ensured. Therefore, continue to refer to Figure 2As shown, in the exemplary embodiment, on the basis of the first victim sub-line 101, the second victim sub-line 102, the first attack sub-line 201 and the second attack sub-line 202, the differential crosstalk noise coupler of the embodiment of the present disclosure further includes a victim differential lead pair 12 and an attack differential lead pair 22. The victim differential lead pair 12 includes a first victim sub-lead 121 and a second victim sub-lead 122, wherein the first victim sub-lead 121 is connected to the first victim sub-line 101, and the second victim sub-lead 122 is connected to the second victim sub-line 102. The attack differential lead pair 22 includes a first attack sub-lead 221 and a second attack sub-lead 222, wherein the first attack sub-lead 221 is connected to the first attack sub-line 201, and the second attack sub-lead 222 is connected to the second attack sub-line 202. The victim differential lead pair 12 is an extension of the victim line 1, and the attack differential lead pair 22 is an extension of the attack line 2, thereby realizing the paired appearance and routing of the two pairs of differential signal lines, the victim line 1 and the attack line 2.

[0055] like Figure 2 As shown, because the victim line 1 and the attack line 2 are located in the same inner layer of the PCB board, and the first attack sub-line 201 is coupled with the first victim sub-line 101 to form a first differential signal line pair 11, and the second attack sub-line 202 is coupled with the second victim sub-line 102 to form a second differential signal line pair 21, based on this situation, if the victim differential lead pair 12 and the attack differential lead pair 22 respectively connected to the victim line 1 and the attack line 2 are also located in the same inner layer, then there will be a situation where the victim differential lead pair 12 and the attack differential lead pair 22 cross, which will cause the two pairs of differential signal lines to be short-circuited. To avoid this situation, in the exemplary embodiment, the victim differential lead pair 12 and the victim line 1 are located in the same inner layer of the PCB board, and the attack differential lead pair 22 and the attack line 2 are located in different inner layers of the PCB board, for example Figure 2 Alternatively, in other exemplary embodiments, the victim differential lead pair 12 and the victim line 1 are located on different inner layers of the PCB board, and the attack differential lead pair 22 and the attack line 2 are located on the same inner layer of the PCB board. For details, see Figure 4 Alternatively, in other exemplary embodiments, the victim differential lead pair 12 and the victim line 1 are located on different inner layers of the PCB board, the attack differential lead pair 22 and the attack line 2 are located on different inner layers of the PCB board, and the victim differential lead pair 12 and the attack differential lead pair 22 are also located on different inner layers of the PCB board, wherein the traces between different inner layers can be connected through corresponding through holes.

[0056] Figure 3A Shows Figure 2 A partial structural diagram of a connection area between the victim differential lead pair 12, the attack differential lead pair 22, the victim line 1 and the attack line 2, Figure 3BShows Figure 2 A partial structural diagram of another connection area between the victim differential lead pair 12, the attack differential lead pair 22, the victim line 1 and the attack line 2, as shown in FIG. Figure 3A , Figure 3B Combined with Figure 2 As shown, in the exemplary embodiment, when the victim differential lead pair 12 and the victim line 1 are located on the same inner layer of the PCB board, and the attack differential lead pair 22 and the attack line 2 are located on different inner layers of the PCB board: the victim differential lead pair 12 is connected to the victim line 1 through the victim transition line 13, and the victim transition line 13 and the victim line 1 are located on the same inner layer of the PCB board; the attack differential lead pair 22 is connected to the attack line 2 through the attack transition through hole 24 and the attack transition line 23, wherein the attack transition line 23 and the attack line 2 are located on the same inner layer of the PCB board, and the attack transition line 23 is connected to the attack line 2, and the attack transition through hole 24 is connected between the attack differential lead pair 22 and the attack transition line 23.

[0057] Specifically, the victim transition line 13 includes a first victim transition sub-line 131 and a second victim transition sub-line 132, the attack transition through hole 24 includes a first attack transition sub-through hole 241 and a second attack transition sub-through hole 242, and the attack transition line 23 includes a first attack transition sub-line 231 and a second attack transition sub-line 232. The first victim sub-lead 121 is connected to the first victim sub-line 101 through the first victim transition sub-line 131, the second victim sub-lead 122 is connected to the second victim sub-line 102 through the second victim transition sub-line 132, and the first victim transition sub-line 131 and the second victim transition sub-line 132 are located in the same inner layer of the PCB board as the victim line 1; the first attack sub-lead 221 is connected to the first attack sub-line 201 through the first attack transition sub-through hole 241 and the first attack transition sub-line 231, and the second attack sub-lead 222 is connected to the second attack sub-line 202 through the second attack transition sub-through hole 242 and the second attack transition sub-line 232. Among them, the first attack transition sub-line 231 and the second attack transition sub-line 232 are located in the same inner layer of the PCB board as the attack line 2, and the first attack transition sub-line 231 is connected to the first attack sub-line 201, and the second attack transition sub-line 232 is connected to the second attack sub-line 202; the first attack transition sub-through hole 241 is connected between the first attack sub-lead 221 and the first attack transition sub-line 231, and the second attack transition sub-through hole 242 is connected between the second attack sub-lead 222 and the second attack transition sub-line 232.

[0058] from Figure 2 , Figure 3A , Figure 3BIt can be seen that the first victim transition sub-line 131 and the second victim transition sub-line 132 are not in parallel, and the impedance of the single-ended line in the differential signal line will be affected by another adjacent parallel single-ended line in the differential signal line. Therefore, when the widths of the first victim sub-lead 121, the first victim transition sub-line 131 and the first victim sub-line 101 are equal, the impedance of the first victim transition sub-line 131 will increase. Therefore, in order to make the impedance of the first victim transition sub-line 131 the same as or close to the impedances of the first victim sub-line 101 and the first victim sub-lead 121, preferably, the width of the first victim transition sub-line 131 needs to be greater than the width of the first victim sub-line 101 and the first victim sub-lead 121, and the same applies to the second victim transition sub-line 132. The specific widths of the first victim transition sub-line 131 and the second victim transition sub-line 132 can be adaptively set according to the actual application scenario.

[0059] Similar to the victim transition line 13, the attack transition line 23 also has the same situation, however, the crosstalk test is performed on the victim line 1, and the width of the attack transition line 23 may not have much effect on the crosstalk test of the victim line 1, but in order to help the crosstalk test result to be more ideal, preferably, the width of the first attack transition sub-line 231 needs to be greater than the width of the first attack sub-line 201 and the first attack sub-lead 221, and the second attack transition sub-line 232 is the same. Specifically, the width of the first attack transition sub-line 231 and the second attack transition sub-line 232 can be adaptively set according to the actual application scenario. In addition, because the structure of the first attack transition sub-through hole 241 is different from that of the first attack sub-lead 221, in order to help the crosstalk test result to be more ideal, the relevant parameters of the first attack transition sub-through hole 241 can also be adaptively set according to the actual application scenario, and the second attack transition sub-through hole 242 is the same.

[0060] In the exemplary embodiment, the attack differential lead pair 22 and the attack line 2 may be located in two adjacent inner layers of the PCB board, or may be located in two non-adjacent inner layers of the PCB board.

[0061] and Figure 2 In the opposite case, that is, the victim differential lead pair 12 and the victim line 1 are located on different inner layers of the PCB board, and the attack differential lead pair 22 and the attack line 2 are located on the same inner layer of the PCB board, the same method can be used. Figure 2 The connection method of the attack differential lead pair 22 and the victim differential lead pair 12 is opposite. Figure 4 is another structural schematic diagram of a differential crosstalk noise coupler according to an exemplary embodiment, Figure 2 compared to, Figure 4 In the illustrated embodiment, the aggressor line 2 and the victim line 1 are merely swapped with each other, and the associated aggressor differential lead pair 22 and victim differential lead pair 12 are also swapped. Figure 5A Shows Figure 4 A partial structural diagram of a connection area between the victim differential lead pair 12, the attack differential lead pair 22, the victim line 1 and the attack line 2, Figure 5B Shows Figure 4 A partial structural diagram of another connection area between the victim differential lead pair 12, the attack differential lead pair 22, the victim line 1 and the attack line 2, as shown in FIG. Figure 5A , Figure 5B Combined with Figure 4 As shown, when the victim differential lead pair 12 and the victim line 1 are located on different inner layers of the PCB board, and the attack differential lead pair 22 and the attack line 2 are located on the same inner layer of the PCB board: the attack differential lead pair 22 is connected to the attack line 2 through the attack transition line 23, and the attack transition line 23 and the attack line 2 are located on the same inner layer of the PCB board; the victim differential lead pair 12 is connected to the victim line 1 through the victim transition through hole 14 and the victim transition line 13, wherein the victim transition line 13 and the victim line 1 are located on the same inner layer of the PCB board, and the victim transition line 13 is connected to the victim line 1, and the victim transition through hole 14 is connected between the victim differential lead pair 12 and the victim transition line 13.

[0062] Specifically, the attack transition line 23 includes a first attack transition sub-line 231 and a second attack transition sub-line 232, the victim transition through-hole 14 includes a first victim transition sub-through-hole 141 and a second victim transition sub-through-hole 142, and the victim transition line 13 includes a first victim transition sub-line 131 and a second victim transition sub-line 132. The first attack sub-lead 221 is connected to the first attack sub-line 201 through the first attack transition sub-line 231, the second attack sub-lead 222 is connected to the second attack sub-line 202 through the second attack transition sub-line 232, and the first attack transition sub-line 231 and the second attack transition sub-line 232 are located in the same inner layer of the PCB board as the attack line 2; the first victim sub-lead 121 is connected to the first victim sub-line 101 through the first victim transition sub-through-hole 141 and the first victim transition sub-line 131, and the second victim sub-lead 122 is connected to the second victim sub-line 102 through the second victim transition sub-through-hole 142 and the second victim transition sub-line 132. Among them, the first victim transition sub-line 131 and the second victim transition sub-line 132 are located in the same inner layer of the PCB board as the victim line 1, and the first victim transition sub-line 131 is connected to the first victim sub-line 101, and the second victim transition sub-line 132 is connected to the second victim sub-line 102; the first victim transition sub-through hole 141 is connected between the first victim sub-lead 121 and the first victim transition sub-line 131, and the second victim transition sub-through hole 142 is connected between the second victim sub-lead 122 and the second victim transition sub-line 132.

[0063] and Figure 2 Similar to the embodiment shown, Figure 4In the implementation shown, in order to make the impedance of the first victim transition sub-line 131 the same as or close to the impedance of the first victim sub-line 101 and the first victim sub-lead 121, preferably, the width of the first victim transition sub-line 131 needs to be greater than the width of the first victim sub-line 101 and the first victim sub-lead 121, and the same applies to the second victim transition sub-line 132. The specific widths of the first victim transition sub-line 131 and the second victim transition sub-line 132 can be adaptively set according to the actual application scenario, and preferably, the width of the first attack transition sub-line 231 needs to be greater than the width of the first attack sub-line 201 and the first attack sub-lead 221, and the same applies to the second attack transition sub-line 232. The specific widths of the first attack transition sub-line 231 and the second attack transition sub-line 232 can be adaptively set according to the actual application scenario. At the same time, since the structure of the first victim transition sub-via 141 is different from that of the first victim sub-lead 121, in order to help the crosstalk test result to be more ideal, the relevant parameters of the first victim transition sub-via 141 also need to be adaptively set according to the actual application scenario, and the same is true for the second victim transition sub-via 142.

[0064] In addition to the structures of the differential crosstalk noise coupler in the above embodiments, in practical applications, a related interface is also required to connect with the equipment in the SerDes test system. Figure 6 is a schematic diagram of the overall structure of a differential crosstalk noise coupler according to an exemplary embodiment, such as Figure 6 As shown, in the exemplary embodiment, the differential crosstalk noise coupler further includes a victim line SMA (SubMiniature version A) interface 15 and an attack line SMA interface 25. The victim line SMA interface 15 is connected to the victim differential lead pair 12, and the attack line SMA interface 25 is connected to the attack differential lead pair 22. It should be noted that, Figure 6 The structure shown is in Figure 2 The structure of the embodiment shown is expanded on the basis of the structure of the embodiment shown. For further wiring details, please refer to Figure 2 As shown and related instructions above.

[0065] In the differential crosstalk noise coupler of the embodiment of the present disclosure, the width of each single-ended line in the differential signal line, line spacing and other parameters involved can adopt the parameters in the relevant technology to meet the transmission requirements of high-speed differential signals, which will not be elaborated here.

[0066] Figure 7 is a schematic diagram of a modeling structure of a simulation section in a differential crosstalk noise coupler according to an exemplary embodiment, Figure 8 Yes Figure 7 Schematic diagram of impedance simulation curve of the structure shown, Fig. 9 Yes Figure 7 The crosstalk simulation curve diagram of the structure shown is as follows. Figure 7 As shown, the simulation section 702 selects the main part of the circuit in the differential crosstalk noise coupler of the embodiment of the present disclosure in PCB701, and the simulation section 702 mainly includes the structure of the victim line 1, the attack line 2 and a section of the lead wire near it. Figure 8 In the figure, the vertical axis corresponds to impedance and the horizontal axis corresponds to Figure 7 The position of the simulation segment 702 in FIG. 1 (represented by time time), the flat area in the middle of the two curves corresponds to the impedance of the first victim sub-line 101 and the second victim sub-line 102 in the simulation segment 702. Figure 8 It can be seen that the impedance of the first victim sub-line 101 and the second victim sub-line 102 can be maintained at about 100 ohms, and the impedance changes of the two differential pairs of victim line 1 and attack line 2 are always stable and can be maintained in the impedance range applicable to differential signal lines, indicating that the impedance of the victim line 1 in the differential crosstalk noise coupler of the embodiment of the present disclosure is not significantly reduced due to the addition of the attack line 2. Fig. 9 It can be seen from the crosstalk simulation results that the crosstalk coupling ability of the attack line 2 to the victim line 1 can reach up to about -28dB, and the coupling ability can still reach -30dB when the coupling frequency band is 30GHz. The coupling ability at the sampling point of 26.56GHz in the coupling frequency band is -33.03dB. When the coupling frequency band reaches 50GHz, the coupling ability does not show serious attenuation and is still around -30dB, indicating that the differential crosstalk noise coupler of the embodiment of the present disclosure can achieve greater noise coupling under the condition of a smaller swing of the noise signal of the attack line 2 (for the SerDes system, the signal swing is usually around 1V, so it is not feasible to increase the crosstalk of the attack line to the victim line by increasing the swing). Supplementary explanation of the crosstalk curve: the existence of RC (resistance and parasitic capacitance) of the signal line will lead to the generation of periodic resonance points. The coupling ability of the crosstalk curve at the resonance point is the weakest. Fig. 9 The frequency points corresponding to the tip positions of the bottoms of the waves in the curve presented in the figure are the resonance points. For the crosstalk coupling of related technologies, such resonance points will exist in the crosstalk curve.

[0067] In an exemplary embodiment, a PCB board is also provided, and the PCB board adopts the differential crosstalk noise coupler of any one of the above embodiments.

[0068] In an exemplary embodiment, a SerDes test system is further provided. The SerDes test system adopts the differential crosstalk noise coupler of any one of the above embodiments.

[0069] The above description is only a preferred embodiment of the present disclosure and is not intended to limit the present disclosure. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present disclosure shall be included in the scope of protection of the present disclosure.

Claims

1. A differential crosstalk noise coupler, characterized in that: include: A victim line, wherein the victim line includes a first victim sub-line and a second victim sub-line, and the first victim sub-line and the second victim sub-line are single-ended lines; An attack line, the attack line comprising a first attack sub-line and a second attack sub-line, the first attack sub-line and the first victim sub-line are coupled to form a first differential signal line pair, and the second attack sub-line and the second victim sub-line are coupled to form a second differential signal line pair; A victim differential lead pair, the victim differential lead pair comprising a first victim sub-lead and a second victim sub-lead, wherein the first victim sub-lead is connected to the first victim sub-lead, and the second victim sub-lead is connected to the second victim sub-lead; An attack differential lead pair, the attack differential lead pair comprising a first attack sub-lead and a second attack sub-lead, wherein the first attack sub-lead is connected to the first attack sub-line, and the second attack sub-lead is connected to the second attack sub-line; The victim differential lead pair and the victim line are located on the same inner layer of the PCB board, and the attack differential lead pair and the attack line are located on different inner layers of the PCB board; or, the victim differential lead pair and the victim line are located on different inner layers of the PCB board, and the attack differential lead pair and the attack line are located on the same inner layer of the PCB board.

2. The differential crosstalk noise coupler according to claim 1, characterized in that: The first victim sub-line, the second victim sub-line, the first attack sub-line and the second attack sub-line all extend in straight lines.

3. The differential crosstalk noise coupler according to claim 1, characterized in that: The victim line and the attack line are located on the same inner layer of the PCB board.

4. The differential crosstalk noise coupler according to claim 1, characterized in that: In the case where the victim differential lead pair and the victim line are located on the same inner layer of the PCB board, and the attack differential lead pair and the attack line are located on different inner layers of the PCB board: The victim differential lead pair is connected to the victim line through a victim transition line, and the victim transition line and the victim line are located on the same inner layer of the PCB board; The attack differential lead pair is connected to the attack line through an attack transition through-hole and an attack transition line, wherein the attack transition line and the attack line are located on the same inner layer of the PCB board, and the attack transition line is connected to the attack line, and the attack transition through-hole is connected between the attack differential lead pair and the attack transition line.

5. The differential crosstalk noise coupler according to claim 1, characterized in that: In the case where the victim differential lead pair and the victim line are located on different inner layers of the PCB board, and the attack differential lead pair and the attack line are located on the same inner layer of the PCB board: The attack differential lead pair is connected to the attack line through an attack transition line, and the attack transition line and the attack line are located on the same inner layer of the PCB board; The victim differential lead pair is connected to the victim line through a victim transition through-hole and a victim transition line, wherein the victim transition line and the victim line are located in the same inner layer of the PCB board, and the victim transition line is connected to the victim line, and the victim transition through-hole is connected between the victim differential lead pair and the victim transition line.

6. The differential crosstalk noise coupler according to claim 1, characterized in that: Also includes: A victim line SMA interface, the victim line SMA interface is connected to the victim differential lead pair; An attack line SMA interface, wherein the attack line SMA interface is connected to the attack differential lead pair.

7. The differential crosstalk noise coupler according to claim 4, characterized in that: The victim transition line includes a first victim transition sub-line and a second victim transition sub-line, the attack transition through-hole includes a first attack transition sub-through-hole and a second attack transition sub-through-hole, and the attack transition line includes a first attack transition sub-line and a second attack transition sub-line; wherein, The first victim sub-lead is connected to the first victim sub-line through the first victim transition sub-line, the second victim sub-lead is connected to the second victim sub-line through the second victim transition sub-line, and the first victim transition sub-line and the second victim transition sub-line are located in the same inner layer of the PCB board as the victim line; The first attack sub-lead is connected to the first attack sub-line through the first attack transition sub-through hole and the first attack transition sub-line, and the second attack sub-lead is connected to the second attack sub-line through the second attack transition sub-through hole and the second attack transition sub-line, wherein the first attack transition sub-line and the second attack transition sub-line are located in the same inner layer of the PCB board as the attack line, and the first attack transition sub-line is connected to the first attack sub-line, the second attack transition sub-line is connected to the second attack sub-line, the first attack transition sub-through hole is connected between the first attack sub-lead and the first attack transition sub-line, and the second attack transition sub-through hole is connected between the second attack sub-lead and the second attack transition sub-line.

8. The differential crosstalk noise coupler according to claim 5, characterized in that: The attack transition line includes a first attack transition sub-line and a second attack transition sub-line, the victim transition through-hole includes a first victim transition sub-through-hole and a second victim transition sub-through-hole, and the victim transition line includes a first victim transition sub-line and a second victim transition sub-line; wherein, The first attack sub-lead is connected to the first attack sub-line through the first attack transition sub-line, the second attack sub-lead is connected to the second attack sub-line through the second attack transition sub-line, and the first attack transition sub-line and the second attack transition sub-line are located in the same inner layer of the PCB board as the attack line; The first victim sub-lead is connected to the first victim sub-line through the first victim transition sub-through hole and the first victim transition sub-line, and the second victim sub-lead is connected to the second victim sub-line through the second victim transition sub-through hole and the second victim transition sub-line, wherein the first victim transition sub-line and the second victim transition sub-line are located in the same inner layer of the PCB board as the victim line, and the first victim transition sub-line is connected to the first victim sub-line, the second victim transition sub-line is connected to the second victim sub-line, the first victim transition sub-through hole is connected between the first victim sub-lead and the first victim transition sub-line, and the second victim transition sub-through hole is connected between the second victim sub-lead and the second victim transition sub-line.

9. A PCB board, characterized in that: A differential crosstalk noise coupler as claimed in any one of claims 1 to 8 is used.

10. A SerDes test system, characterized in that: A differential crosstalk noise coupler as claimed in any one of claims 1 to 8 is used.

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