CN219417378U - Test board and test system - Google Patents

Abstract

The disclosure provides a test board and a test system, and belongs to the technical field of FPC testing. The test board includes a board body, a first test part and a second test part. The first test component comprises a first de-embedded reference line and a first connecting component, wherein the first de-embedded reference line is positioned in a first lamination area of the plate body. The second test component comprises a second de-embedded reference line, a first test line, a third de-embedded reference line and a second connecting component, wherein the second de-embedded reference line and the third de-embedded reference line are positioned in a first lamination area, the first test line is positioned in a second lamination area, and the lamination of the second lamination area is consistent with the lamination of the FPC to be tested area. The S parameter of the first de-embedded reference line and the S parameter of the test line consisting of the second de-embedded reference line, the first test line and the third de-embedded reference line can be measured by the test instrument docking connection part. And then, acquiring the S parameter of the first test line by adopting a de-embedding method, and determining the material parameter of the second lamination area based on the S parameter of the first test line.

Description

Test board and test system

Technical Field

The disclosure relates to the technical field of FPC testing, in particular to a test board and a test system.

Background

The material parameters of the substrate used for the FPC (Flexible Printed Circuit, flexible circuit board) have a decisive effect on the simulation accuracy of the signal integrity of the FPC. The material parameters mainly comprise Dk (Dielectric constant ) value, df (Dissipation factor, dielectric loss factor) value and roughness.

In the related art, a clamp is generally used to measure material parameters of a substrate, and various substrates are respectively fixed in the clamp during measurement, and the material parameters of the various substrates are respectively measured.

However, after the various substrates used in the FPC are bonded, the material parameters of the substrates may also change, so that the material parameters of the substrates that are not bonded, as measured by the jig, do not match the material parameters of the substrates in the FPC.

Disclosure of Invention

The disclosure provides a test board and a test system, which can solve the technical problems existing in the related art, and the technical schemes of the test board and the test system are as follows:

in a first aspect, the present disclosure provides a test board comprising a board body, a first test component, and a second test component;

the board body comprises a first lamination area and a second lamination area, wherein the lamination of the second lamination area is consistent with the lamination of an area to be tested of the FPC (Flexible Printed Circuit, flexible circuit board);

the first test component comprises a first de-embedding reference line and two first connecting components, the first de-embedding reference line is positioned in the first lamination area, and two ends of the first de-embedding reference line are respectively connected with the two first connecting components;

the second test component comprises a second de-embedding reference line, a first test line, a third de-embedding reference line and two second connecting components which are sequentially connected;

the second de-embedded reference line and the third de-embedded reference line are located in the first laminated area, the first test line is located in the second laminated area, and the two second connecting parts are respectively connected with the end parts of the second de-embedded reference line and the end parts of the third de-embedded reference line.

In one possible implementation, the width of the first de-embedded reference line, the width of the second de-embedded reference line, and the width of the third de-embedded reference line are the same;

the length of the second de-embedded reference line and the length of the third de-embedded reference line are both half the length of the first de-embedded reference line.

In one possible implementation manner, the second test components are plural, and the first test lines of at least two of the plural second test components are different.

In one possible implementation, the first test component is a plurality of the first test components, and the first de-embedded reference lines in the plurality of the first test components are the same.

In one possible implementation, the first connection part and the second connection part are both radio frequency connectors; or alternatively, the process may be performed,

the first connecting component and the second connecting component are probe station test points.

In one possible implementation, the test board further includes a third test component and a fourth test component;

the third test component comprises a fourth de-embedded reference line and two third connecting components, the fourth de-embedded reference line is positioned in the first lamination area, and two ends of the fourth de-embedded reference line are respectively connected with the two third connecting components;

the fourth test component comprises a fifth de-embedding reference line, a second test line and a sixth de-embedding reference line which are sequentially connected, and two fourth connection components, wherein the fifth de-embedding reference line and the sixth de-embedding reference line are positioned in the first lamination area, the second test line is positioned in the second lamination area, and the two fourth connection components are respectively connected with the end part of the fifth de-embedding reference line and the end part of the sixth de-embedding reference line;

the first connecting component and the second connecting component are radio frequency connectors, and the third connecting component and the fourth connecting component are probe station test points; or alternatively, the process may be performed,

the first connecting component and the second connecting component are probe station test points, and the third connecting component and the fourth connecting component are radio frequency connectors.

In one possible implementation, the width of the fourth de-embedded reference line, the width of the fifth de-embedded reference line, and the width of the sixth de-embedded reference line are the same;

the length of the fifth de-embedded reference line and the length of the sixth de-embedded reference line are both half the length of the fourth de-embedded reference line.

In one possible implementation manner, the fourth test components are plural, and the second test lines of at least two of the fourth test components in the plural fourth test components are different.

In one possible implementation, the third test component is a plurality of, and fourth de-embedded reference lines in the plurality of third test components are the same.

In one possible implementation, the first lamination area comprises a solid copper plate or a mesh copper plate.

In one possible implementation, the second lamination area includes a solid copper plate and an air layer that are arranged in a stacked manner; or alternatively, the process may be performed,

the second lamination area comprises solid copper plates and electromagnetic shielding films which are arranged in a lamination mode; or alternatively, the process may be performed,

the second lamination area comprises a solid copper plate, an air layer and an electromagnetic shielding film which are arranged in a lamination way; or alternatively, the process may be performed,

the second lamination area comprises grid copper plates and an air layer which are arranged in a lamination mode; or alternatively, the process may be performed,

the second lamination area comprises grid copper plates and electromagnetic shielding films which are arranged in a lamination mode; or alternatively, the process may be performed,

the second lamination area comprises grid copper plates, an air layer and an electromagnetic shielding film which are arranged in a lamination mode.

In a second aspect, the present disclosure provides a test system comprising a test instrument and a test plate according to any one of the first aspects.

The technical scheme provided by the disclosure at least comprises the following beneficial effects:

the present disclosure provides a test board including a board body including a first lamination area and a second lamination area, a lamination of the second lamination area being consistent with a lamination of a region to be tested of an FPC, a first test part, and a second test part. By using the test instrument to interface the first connection part of the first test part and the second connection part of the second test part, respectively, the scattering parameter (S-parameter) of the first de-embedded reference line in the first test part and the S-parameter of the test line consisting of the second de-embedded reference line, the first test line and the third de-embedded reference line in the second test part can be measured. And then, acquiring the S parameter of the first test line by adopting a de-embedding method. The first test line is located on the second lamination area, so that the material parameters of each substrate in the second lamination area after lamination are related to the S parameters of the first test line, the material parameters of the second lamination area can be determined based on the S parameters of the first test line, and the material parameters of the second lamination area are measured as the material parameters of the to-be-tested area of the FPC because the lamination of the second lamination area and the to-be-tested area of the FPC are consistent.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the disclosure.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the disclosure and together with the description, serve to explain the principles of the disclosure. In the drawings:

FIG. 1 is a schematic illustration of a test plate shown in an embodiment of the present disclosure;

FIG. 2 is a schematic diagram of a test plate shown in an embodiment of the present disclosure;

FIG. 3 is a schematic diagram of a test plate shown in an embodiment of the present disclosure;

FIG. 4 is a schematic diagram of a test plate shown in an embodiment of the present disclosure;

FIG. 5 is a schematic diagram of a test plate shown in an embodiment of the present disclosure;

FIG. 6 is a test flow diagram of a test board shown in an embodiment of the present disclosure;

fig. 7 is a test flow diagram of a test board according to an embodiment of the present disclosure.

Legend description:

1. a plate body 11, a first lamination area 12 and a second lamination area;

2. a first test part 21, a first de-embedding reference line 22, a first connection part;

3. a second test part 31, a second de-embedded reference line 32, a first test line 33, a third de-embedded reference line 34, a second connection part;

4. a third test part 41, a fourth de-embedded reference line 42, a third connection part;

5. fourth test part 51, fifth de-embedded reference line 52, second test line 53, sixth de-embedded reference line 54, fourth connection part.

Specific embodiments of the present disclosure have been shown by way of the above drawings and will be described in more detail below. These drawings and the written description are not intended to limit the scope of the disclosed concepts in any way, but rather to illustrate the disclosed concepts to those skilled in the art by reference to specific embodiments.

Detailed Description

For the purposes of clarity, technical solutions and advantages of the present disclosure, the following further details of the embodiments of the present disclosure will be described with reference to the accompanying drawings.

The terminology used in the description of the embodiments of the disclosure is for the purpose of describing the embodiments of the disclosure only and is not intended to be limiting of the disclosure. Unless defined otherwise, technical or scientific terms used herein should be given the ordinary meaning as understood by one of ordinary skill in the art to which this disclosure belongs. The terms "first," "second," "third," and the like in the description and in the claims, do not denote any order, quantity, or importance, but rather are used to distinguish one element from another. Likewise, the terms "a" or "an" and the like do not denote a limitation of quantity, but rather denote the presence of at least one. The word "comprising" or "comprises", and the like, is intended to mean that elements or items that are present in front of "comprising" or "comprising" are included in the word "comprising" or "comprising", and equivalents thereof, without excluding other elements or items. The terms "connected" or "connected," and the like, are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "upper", "lower", "left", "right", etc. are used merely to denote relative positional relationships, which may also change accordingly when the absolute position of the object to be described changes.

The disclosed embodiment provides a test board, as shown in fig. 1, which includes a board body 1, a first test part 2, and a second test part 3. The board body 1 includes a first lamination area 11 and a second lamination area 12, and the lamination of the second lamination area 12 coincides with the lamination of the area to be tested of the FPC (Flexible Printed Circuit, flexible circuit board). The first test part 2 includes a first de-embedded reference line 21 and two first connection parts 22, and the first de-embedded reference line 21 is located in the first lamination area 11, and two ends of the first de-embedded reference line are respectively connected with the two first connection parts 22. The second test part 3 includes a second de-embedded reference line 31, a first test line 32, and a third de-embedded reference line 33, which are sequentially connected, and two second connection parts 34. The second reference line 31 and the third reference line 33 are located in the first laminated area 11, the first test line 32 is located in the second laminated area 12, and two second connection parts 34 are respectively connected with the end of the second reference line 31 and the end of the third reference line 33.

Wherein, the plate body 1 is formed by laminating a base material, a covering film, a reinforcing plate and other auxiliary materials. The substrate of the first laminated area 11 may be solid copper or grid copper, and the lamination of the second laminated area 12 is consistent with the lamination of the area to be tested of the FPC board to be tested actually, so that the material parameters of the substrate of the second laminated area 12 are equivalent to those of the substrate of the area to be tested of the FPC board to be tested actually.

The first, second and third de-embedded reference lines 21, 31 and 33 may be 50ohm signal lines, which may be manufactured using an etching process.

The first and second connection members 22 and 34 are used to externally connect test instruments such as time-frequency domain reflectometry and vector network analyzers. The first connecting part 22 and the second connecting part 34 are the same connecting part, so that the difference of test results caused by the difference of the connecting parts is avoided, and the accuracy of the measurement result of the first test line 32 is ensured.

According to the technical scheme provided by the embodiment of the disclosure, when the material parameters of the base material of a certain area (called as an area to be tested) of a certain FPC board need to be determined, a test board can be manufactured according to the lamination of the area to be tested, wherein the second lamination area 12 of the test board is consistent with the area to be tested, so that the material parameters of the area to be tested are tested and are converted into the material parameters of the second lamination area 12. It should be noted that, when a certain FPC board has a plurality of areas to be tested, a plurality of test boards may be manufactured according to the plurality of areas to be tested, and the second lamination areas 12 of the plurality of test boards are respectively consistent with the plurality of areas to be tested, or a plurality of second lamination areas 12 may be manufactured on one test board, and the plurality of second lamination areas 12 are consistent with the plurality of areas to be tested.

During testing, the scattering parameter (S parameter) of the first de-embedding reference line 21 in the first test part 2 and the S parameter of the test line consisting of the second de-embedding reference line 31, the first test line 32 and the third de-embedding reference line 33 in the second test part 3 can be measured by using the test instrument to respectively dock the first connection part 22 of the first test part 2 and the second connection part 34 of the second test part 3.

Then, based on the S parameter of the first de-embedded reference line 21 and the S parameter of the test line composed of the second de-embedded reference line 31, the first test line 32 and the third de-embedded reference line 33, the S parameter of the first test line 32 may be obtained by using the de-embedding method.

Since the first test line 32 is located in the second lamination area 12, the material parameter of each substrate of the second lamination area 12 after lamination is related to the S parameter of the first test line, so the material parameter of the second lamination area 12 can be determined based on the S parameter of the first test line 32, and since the second lamination area 12 is the same as the area to be tested of the FPC board, the measured material parameter of the second lamination area 12 is the material parameter of the area to be tested of the FPC board. The material parameters of the second lamination area 12 are those of the whole substrate formed by laminating the substrates.

In some examples, as shown in fig. 1, the width of the first de-embedded reference line 21, the width of the second de-embedded reference line 31, and the width of the third de-embedded reference line 33 are the same. The length of the second de-embedded reference line 31 and the length of the third de-embedded reference line 33 are each one half the length of the first de-embedded reference line 21.

In this way, the reference lines for de-embedding on both sides of the first test line 32 are ensured to be symmetrical, and the width of the reference line is the same as that of the first reference line for de-embedding 21, which meets the requirement of a 2×thru de-embedding method, so that the S parameter of the first test line 32 can be accurately measured.

In some examples, as shown in fig. 2, the second test component 3 is a plurality, and the first test lines 32 of at least two second test components 3 in the plurality of second test components 3 are different.

The first test lines 32 of the at least two second test components 3 may be different, or the widths of the first test lines 32 may be different (as shown in fig. 2), or the lengths of the first test lines 32 may be different, or the lengths and the widths of the first test lines 32 may be different.

Since the material parameters of the second laminated area 12 are independent of the length and width of the first test line 32, two different first test lines 32 can be used as a comparison, and if the material parameter results of the second laminated area 12 obtained by the S parameters of the two first test lines 32 are the same, accidental errors of the test results can be eliminated.

Illustratively, as shown in fig. 2, the second test part 3 may be two, and the two first test lines 32 are different.

In some examples, as shown in fig. 3, the first test component 2 is a plurality, and the first de-embedding reference lines 21 in the plurality of first test components 2 are the same.

Thus, during testing, when one of the first de-embedded reference lines 21 is damaged by wear, other first de-embedded reference lines 21 may be used as a replacement for testing. In addition, the S parameters may be measured and obtained for each of the plurality of first de-embedded reference lines 21, and if the S parameters are the same, accidental errors of the test result may be eliminated.

The embodiments of the present disclosure are not limited in the type of first and second connection members 22, 34, and in some examples, as shown in fig. 4 and 5, the first and second connection members 22, 34 are both rf connectors, and the first and second connection members 22, 34 may be used to connect with a test instrument having an rf connector.

In other examples, where the first and second connection members 22, 34 are probe station test points, the first and second connection members 22, 34 may be used to connect with a test instrument having a probe station.

In some examples, as shown in fig. 4 and 5, the test board further comprises a third test part 4 and a fourth test part 5. The third test part 4 includes a fourth de-embedded reference line 41 and two third connection parts 42, and the fourth de-embedded reference line 41 is located in the first laminated area 11, and two ends of the fourth de-embedded reference line are respectively connected with the two third connection parts 42. The fourth test part 5 includes a fifth de-embedded reference line 51, a second test line 52 and a sixth de-embedded reference line 53, which are sequentially connected, and two fourth connection parts 54, the fifth and sixth de-embedded reference lines 51 and 53 being located in the first laminated region 11, the second test line 52 being located in the second laminated region 12, the two fourth connection parts 54 being connected to the ends of the fifth and sixth de-embedded reference lines 51 and 53, respectively.

The types of the third and fourth connection members 42 and 54 are different from the types of the first and second connection members 22 and 34 described above, thereby enabling the test board to be adapted to different test instruments.

The fourth reference line 41, the fifth reference line 51 and the sixth reference line 53 may be signal lines of 50 ohms.

In some examples, as shown in fig. 4 and 5, where the first connection member 22 and the second connection member 34 are both radio frequency connectors, the third connection member 42 and the fourth connection member 54 are both probe station test points.

In other examples, where the first connection member 22 and the second connection member 34 are both probe station test points, the third connection member 42 and the fourth connection member 54 are both radio frequency connectors.

In some examples, as shown in fig. 4 and 5, the width of the fourth de-inlay reference line 41, the width of the fifth de-inlay reference line 51, and the width of the sixth de-inlay reference line 53 are the same. The length of the fifth de-embedded reference line 51 and the length of the sixth de-embedded reference line 53 are each one half the length of the fourth de-embedded reference line 41.

In this way, the reference lines for de-embedding on both sides of the second test line 52 are ensured to be symmetrical, and the width of the reference line is the same as that of the fourth reference line 41 for de-embedding, which meets the requirement of 2×thru de-embedding method, so that the S parameter of the second test line 52 can be accurately measured.

In some examples, as shown in fig. 5, the fourth test component 5 is a plurality, and the second test lines 52 of at least two fourth test components 5 in the plurality of fourth test components 5 are different.

The second test wires 52 of the at least two fourth test components 5 may be different, or the widths of the second test wires 52 may be different (as shown in fig. 5), or the lengths of the second test wires 52 may be different, or the lengths and widths of the second test wires 52 may be different.

Since the material parameters of the second laminated area 12 are independent of the width and length of the second test line 52, two different second test lines 52 may be provided for comparison, and if the material parameter results of the second laminated area 12 obtained by the S parameters of the two second test lines 52 are the same, accidental errors of the test results may be eliminated.

In some examples, as shown in fig. 5, the third test part 4 is a plurality, and the fourth de-inlay reference line 41 in the plurality of third test parts 4 is the same.

Thus, during testing, when a certain fourth de-embedded reference line 41 is damaged by wear, other fourth de-embedded reference lines 41 can be used as a substitute for testing. In addition, the S parameters may be measured and obtained for each of the fourth de-embedded reference lines 41, and if the S parameters are the same, accidental errors of the test result may be eliminated.

The relation of the de-embedded reference lines in the first test part 2 and the third test part 4 is not limited in the embodiments of the present disclosure, and in some examples, as shown in fig. 4 and 5, the width and length of the first de-embedded reference line 21 and the fourth de-embedded reference line 41 are the same.

In the following, a possible implementation form of the test board is provided:

in some examples, as shown in fig. 4, the first test part 2, the second test part 3, the third test part 4, and the fourth test part 5 are all one. The second reference line 31 and the fifth reference line 51 have the same width and length, the first test line 32 and the second test line 52 have the same width and length, and the third reference line 33 and the sixth reference line 53 have the same width and length.

Thus, if the test instrument has both a radio frequency connector and a probe station (or two types of test instruments), the test instrument can be connected with different connecting components to perform two measurements, and if the test results of the second test component 3 and the fourth test component 5 are the same, accidental errors of the test results can be eliminated.

In some examples, as shown in fig. 5, the first test part 2, the second test part 3, the third test part 4, and the fourth test part 5 are all two.

The first reference line 21 and the fourth reference line 41 have the same width and length. The widths of the two first test lines 32 are different, the widths of the two second test lines 52 are different, and the widths and lengths of one first test line 32 and one second test line 52 are the same, and the widths and lengths of the other first test line 32 and the other second test line 52 are the same.

The disclosed embodiments are not limited to the composition of the substrate of the first laminated region 11, and in some examples, the first laminated region 11 includes a solid copper plate or a mesh copper plate. The solid copper plate or the grid copper plate is not pressed with other base materials, so that the manufacturing cost of the test plate can be reduced.

The second stack area 12 is arranged in the same way as the stacks of the areas to be tested of the FPC board.

For example, the second lamination area 12 includes solid copper plates and an air layer (Airgap) arranged in a laminated manner. Alternatively, the second lamination area 12 includes a solid copper plate and an electromagnetic shielding film (EMI film) arranged in a laminated manner. Alternatively, the second lamination zone 12 comprises a laminate arrangement of solid copper plates, airgap and EMI films. Alternatively, the second lamination zone 12 comprises a stacked arrangement of mesh copper plates and Airgap. Alternatively, the second lamination area 12 includes a grid copper plate and an EMI film in a stacked arrangement. Alternatively, the second lamination zone 12 includes a stacked arrangement of mesh copper plates, airgap, and EMI films. Alternatively, the second laminated region 12 may be a solid copper plate or a mesh copper plate.

In some examples, as shown in fig. 1-5, the board body 1, the first lamination area 11, and the second lamination area 12 are all rectangular, which facilitates proper routing on the test board.

In some examples, as shown in fig. 5, two first test parts 2 and two third test parts 4 are arranged in parallel, and the first de-embedding reference line 21 and the fourth de-embedding reference line 41 each extend along both ends in the horizontal direction. The two second test parts 3 and the two fourth test parts 5 are arranged in parallel, and the second decladding reference line 31, the third decladding reference line 41, the fifth decladding reference line 51, and the sixth decladding reference line 53 all extend along both ends in the horizontal direction. Like this, but first test part 2, second test part 3, third test part 4 and fourth test part 5 rational utilization plate body 1's space, make things convenient for test instrument's connection under the prerequisite that occupies less space, still can make wiring on the plate body 1 more pleasing to the eye.

The embodiment of the disclosure also provides a test system, which comprises a test instrument and the test board. The test instrument can be a vector network analyzer, a time domain reflectometer, or other test instruments with radio frequency connectors or probe stations.

In some examples, the test system further includes a simulation device for running simulation software and simulating the test board according to the substrate parameters provided by the FPC board vendor.

In the following, taking an example that the test apparatus has a radio frequency connector and the first connecting part 22 and the second connecting part 34 are radio frequency connectors, a test procedure of the test system provided in the embodiment of the present disclosure will be exemplarily described with reference to fig. 5, 6 and 7:

step 101a: the rf connector of the test instrument is connected to the first connection member 22 for measuring the S-parameter of the first de-embedded reference line 21. During the test, if one of the first test parts 2 is found to wear, the S parameter of the first de-embedding reference line 21 may be measured on the other first test part 2. Or when both the first test parts 2 are intact, the S parameters of the first de-embedded reference lines 21 of both the first test parts 2 are measured, so that errors caused by accidental factors are avoided.

Step 101b: the test instrument is connected to the second connection part 34, and the test instrument can measure the S parameter of the whole test line consisting of the second de-embedded reference line 31, the first test line 32 and the third de-embedded reference line 33.

Step 102: the S parameter of the first test line 32 is obtained by a de-embedding method based on the S parameter of the entire test line composed of the second de-embedding reference line 31, the first test line 32, and the third de-embedding reference line 33 and the S parameter of the first de-embedding reference line 21.

Step 103: the S-parameters of the first test line 32 are converted into insertion loss, return loss and impedance.

Step 201: the test plate was modeled. Specifically, the simulation device is enabled to accurately model the first and second lamination areas 11 and 12 in simulation software according to FPC cut data (including lamination thickness, trace width, etc.) and material parameters of each substrate provided by a vendor. Modeling is then performed in simulation software based on the lengths and widths of the first 21, second 31, first 32, and third 33 de-embedded reference lines on the test board.

Step 202a: the S parameter of the first de-embedding reference line 21 is extracted (which S parameter differs from the measured S parameter).

Step 202b: the S-parameters of the whole test line consisting of the second de-embedded reference line 31, the first test line 32 and the third de-embedded reference line 33 (which are distinguished from the measured S-parameters) are extracted.

Step 203: based on the S parameter of the first de-embedding reference line 21 and the S parameter of the entire test line, the S parameter of the first test line 32 is obtained by the de-embedding method.

Step 204: the S-parameters of the first test line 32 are converted into insertion loss, return loss and impedance.

Step 205: and comparing the simulation results of the insertion loss, the return loss and the impedance with the actual results of the insertion loss, the return loss and the impedance, and if the simulation results are the same as the actual results, the material parameters of the second lamination area 12 in the simulation software are the material parameters of the second lamination area 12. If the simulation results are different, the material parameters of the second laminated area 12 in the simulation software are continuously adjusted until the simulation results of the insertion loss, the return loss and the impedance in the simulation software are the same as the actual results of the insertion loss, the return loss and the impedance.

The simulation results of the insertion loss, return loss, and impedance refer to the results obtained by converting the S parameters of the first test line 32 in the simulation software. The actual results of the insertion loss, return loss, and impedance refer to the results obtained by converting the S-parameters of the first test line 32 acquired by the test instrument.

The test instrument with the probe station is identical to the test instrument with the radio frequency connector in the test process, and will not be described here again.

In addition, in order to ensure that each S parameter measured by the test instrument is accurate, a time domain reflectometer can be adopted to judge whether the impedance deduced from the S parameter in the subsequent test process is correct, so as to assist in judging whether the measured S parameter is accurate. Next, a process of assisting judgment will be described:

step 301a: the impedance of the first de-embedded reference line 21 is measured using a time domain reflectometer.

Step 301b: the impedance of the entire test line consisting of the second de-embedded reference line 31, the first test line 32, and the third de-embedded reference line 33 is measured using a time domain reflectometer.

Step 401a: based on the measured S parameter of the first de-embedded reference line 21, the impedance of the first de-embedded reference line 21 is obtained.

Step 401b: the impedance of the test line composed of the second de-embedded reference line 31, the first test line 32 and the third de-embedded reference line 33 is obtained according to the S parameter of the test line composed of the second de-embedded reference line 31, the first test line 32 and the third de-embedded reference line 33.

Step 402: and verifying whether the S parameter measurement result is accurate.

Specifically, the impedance converted from the S parameter of the first reference line 21 is compared with the impedance of the first reference line 21 directly measured by using a time domain reflectometer, and if the two results are the same (or have a small difference), it indicates that the S parameter of the first reference line 21 is accurately measured.

The impedance obtained by converting the S parameters of the test line composed of the second de-embedded reference line 31, the first test line 32 and the third de-embedded reference line 33 is compared with the impedance of the test line composed of the second de-embedded reference line 31, the first test line 32 and the third de-embedded reference line 33 which is directly measured by using a time domain reflectometer, and if the two results are the same (or have little difference), the measurement of the S parameters of the test line composed of the second de-embedded reference line 31, the first test line 32 and the third de-embedded reference line 33 is accurate.

If the directly measured impedance is not the same as (or very different from) the converted impedance, it indicates that the measured S parameter is inaccurate, and the measurement needs to be re-performed, or whether the test instrument has a fault or whether the test board has damage is checked.

The foregoing description of the preferred embodiments of the present disclosure is provided for the purpose of illustration only, and is not intended to limit the disclosure to the particular embodiments disclosed, but on the contrary, the intention is to cover all modifications, equivalents, alternatives, and alternatives falling within the spirit and scope of the disclosure.

Claims (10)

1. A test board, characterized in that it comprises a board body (1), a first test part (2) and a second test part (3);

the board body (1) comprises a first lamination area (11) and a second lamination area (12), and the lamination of the second lamination area (12) is consistent with the lamination of an area to be tested of the flexible circuit board (FPC);

the first test component (2) comprises a first de-embedding reference line (21) and two first connecting components (22), wherein the first de-embedding reference line (21) is positioned in the first lamination area (11), and two ends of the first de-embedding reference line are respectively connected with the two first connecting components (22);

the second test component (3) comprises a second de-embedding reference line (31), a first test line (32) and a third de-embedding reference line (33) which are sequentially connected, and two second connecting components (34);

the second de-embedding reference line (31) and the third de-embedding reference line (33) are located in the first lamination area (11), the first test line (32) is located in the second lamination area (12), and the two second connecting components (34) are respectively connected with the end parts of the second de-embedding reference line (31) and the end parts of the third de-embedding reference line (33).

2. The test board of claim 1, wherein the width of the first de-embedded reference line (21), the width of the second de-embedded reference line (31) and the width of the third de-embedded reference line (33) are the same;

the length of the second de-embedding reference line (31) and the length of the third de-embedding reference line (33) are each half of the length of the first de-embedding reference line (21).

3. The test board of claim 1, wherein the second test component (3) is a plurality, and the first test lines (32) of at least two of the second test components (3) in the plurality of second test components (3) are different.

4. The test board of claim 1, wherein the first test part (2) is plural, and first de-embedding reference lines (21) in the plural first test parts (2) are identical.

5. The test board of claim 1, wherein the first connection member (22) and the second connection member (34) are each radio frequency connectors; or alternatively, the process may be performed,

the first connection member (22) and the second connection member (34) are both probe station test points.

6. A test board according to any one of claims 1-5, characterized in that the test board further comprises a third test part (4) and a fourth test part (5);

the third test component (4) comprises a fourth de-embedding reference line (41) and two third connecting components (42), wherein the fourth de-embedding reference line (41) is positioned in the first lamination area (11), and two ends of the fourth de-embedding reference line are respectively connected with the two third connecting components (42);

the fourth test component (5) comprises a fifth de-embedding reference line (51), a second test line (52) and a sixth de-embedding reference line (53) which are sequentially connected, and two fourth connection components (54), wherein the fifth de-embedding reference line (51) and the sixth de-embedding reference line (53) are positioned in the first lamination area (11), the second test line (52) is positioned in the second lamination area (12), and the two fourth connection components (54) are respectively connected with the end part of the fifth de-embedding reference line (51) and the end part of the sixth de-embedding reference line (53);

the first connecting component (22) and the second connecting component (34) are radio frequency connectors, and the third connecting component (42) and the fourth connecting component (54) are probe station test points; or alternatively, the process may be performed,

the first connecting part (22) and the second connecting part (34) are probe station test points, and the third connecting part (42) and the fourth connecting part (54) are radio frequency connectors.

7. The test board of claim 6, wherein the width of the fourth de-embedded reference line (41), the width of the fifth de-embedded reference line (51) and the width of the sixth de-embedded reference line (53) are the same;

the length of the fifth de-embedding reference line (51) and the length of the sixth de-embedding reference line (53) are each half of the length of the fourth de-embedding reference line (41).

8. A test board according to any one of claims 1-5, characterized in that the first laminate region (11) comprises a solid copper board or a grid copper board.

9. The test panel according to any one of claims 1-5, wherein the second lamination zone (12) comprises a laminated arrangement of solid copper plates and an air layer; or alternatively, the process may be performed,

the second lamination area (12) comprises solid copper plates and electromagnetic shielding films which are arranged in a lamination mode; or alternatively, the process may be performed,

the second lamination area (12) comprises a solid copper plate, an air layer and an electromagnetic shielding film which are arranged in a lamination mode; or alternatively, the process may be performed,

the second lamination area (12) comprises grid copper plates and an air layer which are arranged in a lamination mode; or alternatively, the process may be performed,

the second lamination area (12) comprises grid copper plates and electromagnetic shielding films which are arranged in a lamination mode; or alternatively, the process may be performed,

the second lamination area (12) comprises a grid copper plate, an air layer and an electromagnetic shielding film which are arranged in a lamination mode.

10. A test system comprising a test instrument and a test plate according to any one of claims 1-9.