A multi-channel de-embedded automotive Ethernet test board

Abstract

This utility model discloses a multi-channel de-embedding automotive Ethernet test board, comprising: a board body, a terminating matching resistor, two first channel groups, two second channel groups, a first equal-length reference circuit, and a second equal-length reference circuit. The terminating matching resistor, the first channel groups, the second channel groups, the first equal-length reference circuit, and the second equal-length reference circuit are all disposed on the board body. The two first channel groups are arranged linearly, and the two second channel groups are arranged in parallel. The first channel groups cooperate with the first equal-length reference circuit, and the second channel groups cooperate with the second equal-length reference circuit. Both the first and second channel groups are connected to the terminating matching resistor. Through the application of this utility model, a multi-channel de-embedding automotive Ethernet test board is proposed, which can not only effectively solve the problem of inconsistent circuit lengths between channels in traditional test boards, but also eliminate transmission loss and phase shift introduced by the test fixture, thereby accurately measuring key indicators such as return loss and insertion loss.

Description

Technical Field

[0001] This utility model relates to the field of test board technology, and in particular to a multi-channel de-embedded automotive Ethernet test board. Background Technology

[0002] As a key hardware testing device for verifying the performance of automotive Ethernet communication systems, the automotive Ethernet test board integrates physical layer and protocol layer verification capabilities. By simulating the automotive network environment, it can automate the testing of Ethernet controllers in terms of signal integrity, protocol compliance, and environmental adaptability. It can be used to measure important parameters such as differential impedance, return loss, and transmission delay. However, in the field of automotive network testing, traditional Ethernet test boards still have several technical limitations: Firstly, there's the issue of channel asymmetry. In today's automotive Ethernet applications, the demand for 1000BASE-T1 multi-link synchronous testing is increasingly common, but existing single-channel test equipment struggles to meet this requirement. Differences in PCB trace length between channels lead to significant transmission delay deviations, violating the ±50ps clock tolerance requirement specified in the IEEE 802.3bw standard. Secondly, there's the problem of de-embedding calibration defects. Traditional test boards typically use fixed S-parameter compensation for fixture loss during de-embedding calibration. However, this method is severely inadequate at high frequencies. It fails to consider the phase nonlinear distortion caused by connector parasitic capacitance. When connectors operate at high frequencies, their parasitic capacitance has a complex effect on the signal, causing nonlinear phase changes. Traditional de-embedding calibration methods ignore this, resulting in high return loss test errors. Thirdly, there is the problem that the insertion loss of the test board cannot be removed from the final measurement results. The test board itself introduces insertion loss during signal transmission, but the existing technology cannot effectively remove this insertion loss from the final measurement results. This is because there is a lack of effective algorithms or circuit designs to accurately measure and compensate for the insertion loss of the test board itself, so that the final test results include the interference caused by the insertion loss of the test board and cannot truly reflect the performance of the tested object. Utility Model Content

[0003] In view of this, in order to solve the above problems, the purpose of this utility model is to provide a multi-channel de-embedding automotive Ethernet test board, including: a board body, a terminating matching resistor, two first channel groups, two second channel groups, a first equal-length reference circuit, and a second equal-length reference circuit. The board body is T-shaped. The terminating matching resistor, the first channel groups, the second channel groups, the first equal-length reference circuit, and the second equal-length reference circuit are all disposed on the board body. The two first channel groups are arranged linearly, and one second channel group is disposed above the other second channel group. The two second channel groups are arranged in parallel. The first channel group cooperates with the first equal-length reference circuit, and the second channel group cooperates with the second equal-length reference circuit. Both the first channel group and the second channel group are connected to the terminating matching resistor.

[0004] In another preferred embodiment, the board body includes: a first part and a second part, the first part being connected to the second part, the terminal matching resistor, the first channel group and the second channel group being disposed in the first part, and the first equal-length reference circuit and the second equal-length reference circuit being disposed in the second part.

[0005] In another preferred embodiment, the first equal-length reference circuit includes: a first SMA interface and a second SMA interface, the first SMA interface and the second SMA interface are disposed at both ends of one side of the second part, and the first SMA interface and the second SMA interface are arranged facing each other, and the first SMA interface is connected to the second SMA interface through a wire harness.

[0006] In another preferred embodiment, the second equal-length reference circuit includes a third SMA interface and a fourth SMA interface, which are disposed at both ends on the other side of the second part and face each other. The third SMA interface is connected to the fourth SMA interface via a wire harness.

[0007] In another preferred embodiment, the first channel group includes a fifth SMA interface and a sixth SMA interface, both of which are disposed on the side of the first portion closer to the second portion, with the fifth SMA interface disposed above the sixth SMA interface.

[0008] In another preferred embodiment, the second channel group includes a seventh SMA interface and an eighth SMA interface, both of which are disposed on the first portion, with the seventh SMA interface disposed on the side of the eighth SMA interface away from the fifth SMA interface.

[0009] In another preferred embodiment, the fifth SMA interface, the sixth SMA interface, the seventh SMA interface, and the eighth SMA interface are all connected to the terminal matching resistor via a wiring harness.

[0010] In another preferred embodiment, the length of the wiring harness connecting the fifth SMA interface to the terminal matching resistor plus the length of the wiring harness connecting the sixth SMA interface to the terminal matching resistor is equal to the length of the wiring harness connecting the first SMA interface to the second SMA interface.

[0011] In another preferred embodiment, the length of the wiring harness connecting the seventh SMA interface to the terminal matching resistor plus the length of the wiring harness connecting the eighth SMA interface to the terminal matching resistor is equal to the length of the wiring harness connecting the third SMA interface to the fourth SMA interface.

[0012] The present invention, by adopting the above-mentioned technical solution, has the following positive effects compared with the prior art: By applying the present invention, a multi-channel de-embedding automotive Ethernet test board is proposed, which can not only effectively solve the problem of inconsistent circuit lengths between channels of traditional test boards and improve test accuracy, but also eliminate transmission loss and phase offset introduced by test fixtures, cables and connectors, thereby restoring the true signal quality and accurately measuring key indicators such as return loss and insertion loss; in addition, it can simultaneously complete the parallel testing of multiple sets of wire harnesses or connectors, which can greatly shorten the test time and improve production line efficiency compared with traditional single-channel or few-channel test boards. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the structure of a multi-channel de-embedded automotive Ethernet test board according to the present invention; Figure 2 This is an internal structural diagram of a multi-channel de-embedded automotive Ethernet test board according to the present invention.

[0014] In the attached image:

[0015] 1. Board body; 2. Termination matching resistor; 3. First channel group; 4. Second channel group; 5. First equal-length reference circuit; 6. Second equal-length reference circuit; 31. Fifth SMA interface; 32. Sixth SMA interface; 41. Seventh SMA interface; 42. Eighth SMA interface; 51. First SMA interface; 52. Second SMA interface; 61. Third SMA interface; 62. Fourth SMA interface. Detailed Implementation

[0016] The technical solution of this utility model will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0017] In the description of this utility model, it should be understood that the orientation or positional relationship indicated by terms such as "upper", "lower", "left", "right", "inner", "outer", "front", "back", "horizontal", and "vertical" are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model, and are not intended to indicate or imply that the device or component referred to must have a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0018] It should be noted that the terms "horizontal" and "vertical" in this utility model are used to describe approximate positional relationships, and not strictly "horizontal plane" or "vertical plane".

[0019] like Figure 1-2 The diagram illustrates a preferred embodiment of a multi-channel de-embedding automotive Ethernet test board, comprising: a board body 1, a terminating resistor 2, two first channel groups 3, two second channel groups 4, a first equal-length reference circuit 5, and a second equal-length reference circuit 6. The board body 1 is T-shaped. The terminating resistor 2, the first channel groups 3, the second channel groups 4, the first equal-length reference circuit 5, and the second equal-length reference circuit 6 are all disposed on the board body 1. The two first channel groups 3 are arranged linearly, and one second channel group 4 is disposed above the other. The two second channel groups 4 are arranged in parallel. The first channel group 3 cooperates with the first equal-length reference circuit 5, and the second channel group 4 cooperates with the second equal-length reference circuit 6. Both the first channel group 3 and the second channel group 4 are connected to the terminating resistor 2. Furthermore, by setting the first reference circuit 5, the insertion loss value of the first channel group 3 can be obtained. Subtracting the corresponding insertion loss value from the total result measured by the first channel group 3 can avoid interference caused by insertion loss of the test board, making the test results more accurate. By setting the second reference circuit 6, the insertion loss value of the second channel group 4 can be obtained.

[0020] Furthermore, in a preferred embodiment, the two first channel groups 3 are arranged symmetrically, and the two second channel groups 4 are arranged symmetrically.

[0021] Furthermore, in a preferred embodiment, the board 1 includes: a first part and a second part, the first part being connected to the second part, the terminal matching resistor 2, the first channel group 3 and the second channel group 4 being disposed in the first part, and the first equal-length reference circuit 5 and the second equal-length reference circuit 6 being disposed in the second part.

[0022] Furthermore, as a preferred embodiment, the first equal-length reference circuit 5 includes: a first SMA interface 51 and a second SMA interface 52. The first SMA interface 51 and the second SMA interface 52 are disposed at both ends of one side of the second part, and the first SMA interface 51 and the second SMA interface 52 are arranged facing each other. The first SMA interface 51 is connected to the second SMA interface 52 through a wire harness.

[0023] Furthermore, as a preferred embodiment, the second equal-length reference circuit 6 includes a third SMA interface 61 and a fourth SMA interface 62, which are disposed at both ends on the other side of the second part and face each other. The third SMA interface 61 is connected to the fourth SMA interface 62 via a wire harness.

[0024] Furthermore, as a preferred embodiment, the first channel group 3 includes a fifth SMA interface 31 and a sixth SMA interface 32, both of which are disposed on the side of the first part closer to the second part, with the fifth SMA interface 31 disposed above the sixth SMA interface 32.

[0025] Furthermore, as a preferred embodiment, the second channel group 4 includes a seventh SMA interface 41 and an eighth SMA interface 42, both of which are disposed on the first part, with the seventh SMA interface 41 disposed on the side of the eighth SMA interface 42 away from the fifth SMA interface.

[0026] Furthermore, as a preferred embodiment, the fifth SMA interface 31, the sixth SMA interface 32, the seventh SMA interface 41, and the eighth SMA interface 42 are all connected to the terminal matching resistor 2 via a wiring harness.

[0027] Furthermore, as a preferred embodiment, the length of the wire harness connecting the fifth SMA interface 31 and the terminal matching resistor 2 plus the length of the wire harness connecting the sixth SMA interface 32 and the terminal matching resistor 2 is equal to the length of the wire harness connecting the first SMA interface 51 and the second SMA interface 52, so as to ensure that the first channel group 3 is consistent with the first equal-length reference circuit 5 in terms of signal transmission delay, thereby helping to solve the channel asymmetry problem.

[0028] Furthermore, as a preferred embodiment, the length of the wiring harness connecting the seventh SMA interface 41 and the terminal matching resistor 2 plus the length of the wiring harness connecting the eighth SMA interface 42 and the terminal matching resistor 2 is equal to the length of the wiring harness connecting the third SMA interface 61 and the fourth SMA interface 62, to ensure the consistency of the second channel group 4 and the second equal-length reference circuit 6 in signal transmission delay.

[0029] The working principle of this utility model is as follows: When performing automotive Ethernet testing, the signal under test can be accessed from an external device to the test board. For the first channel group 3, the signal can enter from the fifth SMA interface 1, and then the signal will be transmitted along the wire harness connecting the fifth SMA interface 1 and the terminal matching resistor 2. After reaching the terminal matching resistor 2, the signal is matched and then output from the sixth SMA interface 32 through the wire harness connecting the sixth SMA interface 32 and the terminal matching resistor 2. Since the length of the wiring harness connecting the fifth SMA interface 31 and the terminal matching resistor 2 plus the length of the wiring harness connecting the sixth SMA interface 32 and the terminal matching resistor 2 are equal to the length of the wiring harness connecting the first SMA interface 51 and the second SMA interface 52, the transmission delay of the signal in the first channel group 3 is consistent with the transmission delay of the signal in the first equal-length reference circuit 5. In this way, the transmission delay of the first channel group 3 can be accurately calibrated by comparing it with the first equal-length reference circuit 5, thus solving the channel asymmetry problem. At the same time, during the de-embedding calibration process, by comparing the difference between the signal transmission of the first channel group 3 and the signal transmission of the first equal-length reference circuit 5, the transmission loss and phase shift introduced by the test fixture can be analyzed, and then compensation can be performed to restore the true signal quality and accurately measure key indicators such as return loss and insertion loss. Similarly, for the second channel group 4, the signal enters from the seventh SMA interface 41 and exits from the eighth SMA interface 42. Based on the equal-length design with the second equal-length reference circuit 6 and the same de-embedding calibration principle, accurate testing of the second channel group 4 can be achieved.

[0030] The above description is only a preferred embodiment of the present invention and is not intended to limit the implementation and protection scope of the present invention.

[0031] In addition to the above, the present invention also has the following embodiments: In a further embodiment of the present invention, in the mass production testing scenario of automotive Ethernet devices, multiple wire harnesses or connectors under test can be connected to the SMA interfaces of different channel groups respectively, so as to perform parallel testing on multiple groups of wire harnesses or connectors, thereby improving testing efficiency and meeting the needs of automotive Ethernet for high-precision and high-efficiency testing in the mass production and R&D stages.

[0032] The above description is only a preferred embodiment of the present utility model and does not limit the implementation method and protection scope of the present utility model. Those skilled in the art should realize that all solutions obtained by equivalent substitutions and obvious changes made based on the description and illustrations of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A multi-channel de-embedding automotive Ethernet test board, characterized in that, include: The board includes a terminating resistor, two first channel groups, two second channel groups, a first equal-length reference circuit, and a second equal-length reference circuit. The board is T-shaped. The terminating resistor, the first channel groups, the second channel groups, the first equal-length reference circuit, and the second equal-length reference circuit are all disposed on the board. The two first channel groups are arranged linearly, and one second channel group is disposed above the other second channel group. The two second channel groups are arranged in parallel. The first channel groups cooperate with the first equal-length reference circuit, and the second channel groups cooperate with the second equal-length reference circuit. Both the first channel groups and the second channel groups are connected to the terminating resistor.

2. The multi-channel de-embedding automotive Ethernet test board according to claim 1, characterized in that, The board body includes a first part and a second part, the first part being connected to the second part, the terminal matching resistor, the first channel group and the second channel group being disposed in the first part, and the first equal-length reference circuit and the second equal-length reference circuit being disposed in the second part.

3. The multi-channel de-embedding automotive Ethernet test board according to claim 2, characterized in that, The first equal-length reference circuit includes a first SMA interface and a second SMA interface. The first SMA interface and the second SMA interface are disposed at both ends of one side of the second part, and the first SMA interface and the second SMA interface are arranged facing each other. The first SMA interface is connected to the second SMA interface through a wire harness.

4. The multi-channel de-embedding automotive Ethernet test board according to claim 3, characterized in that, The second equal-length reference circuit includes a third SMA interface and a fourth SMA interface, which are located at both ends on the other side of the second part and face each other. The third SMA interface is connected to the fourth SMA interface via a wire harness.

5. The multi-channel de-embedding automotive Ethernet test board according to claim 4, characterized in that, The first channel group includes a fifth SMA interface and a sixth SMA interface. Both the fifth SMA interface and the sixth SMA interface are located on the side of the first part closer to the second part, with the fifth SMA interface located above the sixth SMA interface.

6. The multi-channel de-embedding automotive Ethernet test board according to claim 5, characterized in that, The second channel group includes a seventh SMA interface and an eighth SMA interface, both of which are located on the first part, with the seventh SMA interface located on the side of the eighth SMA interface away from the fifth SMA interface.

7. The multi-channel de-embedding automotive Ethernet test board according to claim 6, characterized in that, The fifth SMA interface, the sixth SMA interface, the seventh SMA interface, and the eighth SMA interface are all connected to the terminal matching resistor via a wiring harness.

8. The multi-channel de-embedding automotive Ethernet test board according to claim 6, characterized in that, The length of the wiring harness connecting the fifth SMA interface to the terminal matching resistor plus the length of the wiring harness connecting the sixth SMA interface to the terminal matching resistor is equal to the length of the wiring harness connecting the first SMA interface to the second SMA interface.

9. The multi-channel de-embedding automotive Ethernet test board according to claim 6, characterized in that, The length of the wiring harness connecting the seventh SMA interface to the terminal matching resistor plus the length of the wiring harness connecting the eighth SMA interface to the terminal matching resistor is equal to the length of the wiring harness connecting the third SMA interface to the fourth SMA interface.

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