General test method for S parameter of electronic component

Abstract

The invention provides an electronic component S parameter general test method, which comprises the steps of instrument connection, network analyzer setting, network analyzer calibration, test fixture calibration (de-embedding), DUT test and the like, and can overcome various influences in the S parameter test process, including the influence of network analyzer system errors, the influence of fixtures and the like. Therefore, the S parameter of the electronic component can be accurately measured.

Description

Technical Field

[0001] The invention belongs to the technical field of electronic component testing, and in particular relates to a universal S parameter testing method for electronic components. Background Art

[0002] S parameters (Scattering Parameters, also known as scattering parameters) are very effective parameters used to describe signal transmission in the RF band and are often used in the analysis and design of RF devices and circuits. S parameters describe the transmission and scattering of high-frequency signals in multi-port networks. Through S parameters, we can understand the transmission characteristics and matching characteristics of high-frequency devices, such as gain, bandwidth, and standing wave ratio. By using S parameters to establish a unified device model, designers can intuitively understand the transmission characteristics of the device and quickly evaluate its performance in the entire system.

[0003] The accuracy and precision of electronic component models that use S parameters as indicators to evaluate key parameters will largely depend on the S parameter test itself. The sources of influence on the accuracy of test data are multifaceted, existing in the test system construction, calibration and de-embedding, etc. Therefore, a complete set of S parameter test processes and procedures is essential. Summary of the invention

[0004] In view of this, an object of the present invention is to provide a universal test method for S parameters of electronic components, which can accurately measure the S parameters of electronic components.

[0005] An S parameter testing method for electronic components, comprising:

[0006] Calibrate the set network analyzer;

[0007] After the network analyzer is calibrated, the test fixture is calibrated based on three calibration components, including:

[0008] Make TRL calibration pieces, including Thru calibration pieces, Line calibration pieces, and Open calibration pieces. All three pieces correspond to the test fixture. The Thru calibration piece corresponds to the through state of the test fixture, the Line calibration piece corresponds to the transmission state of the test fixture, and the Open calibration piece corresponds to the reflection state of the test fixture.

[0009] According to the corresponding port positions, the Thru calibration piece, the Line calibration piece, and the Open calibration piece are connected to the network analyzer through cables in sequence. After the network analyzer performs a frequency sweep, the test result files of the three calibration pieces are obtained. When testing the Open calibration piece, the connection between port 1 of the Open calibration piece and the network analyzer is disconnected, and only port 2 is connected. The network analyzer performs a frequency sweep to obtain the test result. Then, the connection between port 2 of the Open calibration piece and the network analyzer is disconnected, and only port 1 is connected. The network analyzer performs a frequency sweep to obtain the test result. The test result files of the Thru calibration piece, the Line calibration piece, and the Open calibration piece obtained by the test are simulated to generate the S parameters of the three calibration pieces, which are expressed as

[0010] After the test fixture calibration is completed, the test fixture with the DUT installed is tested using the calibrated network analyzer, where Figure 2 As shown in the figure, the DUT is fixed on the fixture. Two electrodes are set on the fixture to lead out the two ports of the DUT. The two ports are then connected to the network analyzer through cables. The network analyzer sweeps the frequency of the connected DUT and the fixture to obtain the test results.

[0011] Finally, combined with the S parameters Get the S parameters of the electronic components under test after de-embedding As shown in the following formula:

[0012]

[0013] Preferably, the network analyzer settings include:

[0014] 1) Set the frequency range and step size to be calibrated as needed;

[0015] 2) Set the output power of the network analyzer during calibration, and after the setting is completed, check the box and turn on the power switch;

[0016] 3) Set the intermediate frequency bandwidth of the network analyzer during calibration to a value between 100Hz-1KHz.

[0017] Preferably, the network analyzer and the cable are calibrated. The specific calibration process is as follows:

[0018] Step 31: Create a calibration model

[0019] Edit the calibration box name and description;

[0020] Set the connector type to TRL and set the frequency range;

[0021] Add calibration parts and corresponding parameters;

[0022] After editing is completed, the calibration parts box will generate the calibration parts box corresponding to the test fixture;

[0023] Step 32: Instrument calibration

[0024] Set the frequency range and IF bandwidth in the vector network analyzer;

[0025] Select the calibration type;

[0026] Connect the SHORT standard, LINE standard, and THRU standard to calibrate respectively;

[0027] After the calibration is completed, the standing wave insertion loss will be reset to zero. If the zeroing state is not ideal, recalibration is required.

[0028] Step 33: Set up the test interface

[0029] Add a new test channel: Click Trace / Chan--Trace--New Trace, select S11, S22, S12, S21 and click OK; click Format to set the unit format.

[0030] Furthermore, after the network analyzer is calibrated, keep the Thru standards of ports 1 and 2 connected to the network analyzer, create a new track on the network analyzer, and check S21 and S12 in the S parameters. If the tracks of the two are basically consistent and located near 0dB, and the maximum error range does not exceed ±0.05dB, then the calibration result meets the conditions.

[0031] Furthermore, it also includes: after the test of the device under test (DUT) is completed, the S21 and S12 parameters of the Thru calibration component are tested again, and compared with the S21 and S12 parameter curves obtained during the calibration of the network analyzer. If the trajectories of the two S21 and two S12 parameters are basically consistent and are located near 0dB, the drift error of this test process is small and the test is qualified.

[0032] The present invention has the following beneficial effects:

[0033] The present invention provides a general S parameter test method for electronic components, including instrument connection, network analyzer setting, network analyzer calibration, test fixture calibration (de-embedding), device under test (DUT) testing, etc. The method of the present invention can overcome various influences in the S parameter test process, including the influence of network analyzer system error, fixture influence, etc., so as to accurately measure the S parameters of electronic components. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 A detailed flow chart of the general method for S-parameter testing of electronic components provided by the present invention;

[0035] Figure 2 It is the schematic diagram of the S parameter test device;

[0036] Figure 3(a) is a physical picture of the Thru calibration component, Figure 3(b) is a physical picture of the Line calibration component, Figure 3(c1) is a physical picture of the Open calibration component connected to port 1, and Figure 3(c2) is a physical picture of the Open calibration component connected to port 2;

[0037] Figure 4 This is a schematic diagram of the de-embedding principle of the two-port network analyzer for testing S parameters of the present invention. DETAILED DESCRIPTION

[0038] The present invention is described in detail below with reference to the accompanying drawings and embodiments.

[0039] like Figure 1 As shown, a flowchart of a general method for S parameter testing of electronic components in an embodiment of the present invention includes:

[0040] Step 1, Instrument connection

[0041] According to the different interfaces of the DUT, select the appropriate test cable and calibration parts, and try to avoid using adapters with different calibers to avoid waveguide leakage and affect the test quality. Connect the test cable to the network analyzer correctly, and fix the test cable after determining the spacing to reduce the situation of touching the test cable when replacing the calibration parts.

[0042] Step 2, Network Analyzer Setup

[0043] 1) Set the frequency range and step size to be calibrated as needed (the smaller the step size, the more accurate the test result, but the time required will also increase.)

[0044] 2) Set the output power of the network analyzer during calibration, and after the setting is completed, check the box and turn on the power switch.

[0045] 3) Set the intermediate frequency bandwidth of the network analyzer during calibration. The recommended value is between 100Hz-1KHz.

[0046] Step 3: Calibrate the network analyzer and cables. The specific calibration process is as follows:

[0047] Take Agilent Technologies PNA Network Analyzer N5222A and TRL standard parts as an example:

[0048] Step 31: Create a calibration model

[0049] Edit the calibration box name and description;

[0050] Set the connector type to TRL and set the frequency range;

[0051] Add calibration parts and corresponding parameters;

[0052] After editing is completed, the calibration parts box corresponding to the fixture will be generated in the calibration parts box.

[0053] Step 32: Instrument calibration

[0054] Set the frequency range and IF bandwidth in the vector network analyzer;

[0055] Select the calibration type;

[0056] Connect SHORT, LINE, and THRU respectively for calibration;

[0057] After the calibration is completed, the standing wave insertion loss will be reset to zero. If the zeroing state is not ideal, recalibration is required.

[0058] Step 33: Set up the test interface

[0059] Add a new test channel: Click Trace / Chan--Trace--New Trace, select S11, S22, S12, S21 and click OK; click Format to set the unit format.

[0060] In addition, after the network analyzer is calibrated, do not rush to remove the Thru standard parts of ports 1 and 2. Create a new track on the network and check S21 and S12. If the calibration result meets the conditions, you should be able to see that the tracks of the two are basically aligned and located near 0dB, with a maximum error range of no more than ±0.05dB.

[0061] Step 4: Test fixture calibration based on three calibration pieces (de-embedding)

[0062] Connect the test fixture to the test cable end of the network analyzer and calibrate the test fixture. The specific calibration process is as follows:

[0063] Take the de-embedding of the TRL calibration piece as an example (the Thru calibration piece, Line calibration piece, and Open calibration piece here all correspond to the fixture, which is different from the standard piece used for network analyzer calibration in step 3, where the Thru piece corresponds to the through state of the test fixture, the Line piece corresponds to the transmission state of the test fixture, and the Open piece corresponds to the reflection state of the test fixture).

[0064] Connect the cables, and connect the Thru calibration piece, Line calibration piece, and Open calibration piece to the network analyzer through the cables according to the corresponding port positions. After the network analyzer performs a frequency sweep, the test result files of the three calibration pieces are obtained and saved as s2p files for subsequent inspection. When testing the Open calibration piece, disconnect the connection between port 1 of the Open calibration piece and the network analyzer, connect only port 2, and perform a frequency sweep on the network analyzer to obtain the test result. Then disconnect the connection between port 2 of the Open calibration piece and the network analyzer, connect only port 1, and perform a frequency sweep on the network analyzer to obtain the test result.

[0065] Import the test result files of the Thru calibration component, Line calibration component, and Open calibration component obtained from the test into the Test_Fixture_Cal schematic diagram. Click Simulate to generate a set of S parameters of the calibration component, which are expressed as Among them, the S parameters obtained by the two-port vector network analyzer test are a 2*2 matrix Among them, A represents S11, B represents S12, C represents S21, and D represents S22.

[0066] Step 5: Testing of the DUT

[0067] After the test fixture is calibrated and qualified in step 4, the test fixture with the DUT installed is tested using a network analyzer to obtain the S parameters of the test sample including the tested fixture, which are expressed as;

[0068] Among them, Figure 2 As shown in the figure, the DUT is fixed on the fixture. Two electrodes are set on the fixture to lead out the two ports of the DUT. The two ports are then connected to the network analyzer through cables. The network analyzer sweeps the frequency of the connected DUT and the fixture to obtain the test results.

[0069] Combined with a set of S parameters of the calibration component obtained in step 4 Get the S parameters of the electronic components under test after de-embedding As shown in the following formula:

[0070]

[0071] Step 6: Save the measured S parameter data or SNP file.

[0072] Step 7, Thru test (consistency verification)

[0073] After the DUT test is completed, the S21 and S12 parameters of the Thru calibration component are tested again and compared with the S21 and S12 parameter curves obtained during the network analyzer calibration in step 3. If the trajectories of the two S21 and two S12 parameters are basically consistent and are located near 0dB, the drift error of this test process is small and the test is qualified.

[0074] In summary, the above are only preferred embodiments of the present invention and are not intended to limit the protection scope of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for testing S parameters of electronic components, characterized in that: include: Calibrate the set network analyzer; After the network analyzer is calibrated, the test fixture is calibrated based on three calibration components, including: Make TRL calibration pieces, including Thru calibration pieces, Line calibration pieces, and Open calibration pieces. All three pieces correspond to the test fixture. The Thru calibration piece corresponds to the through state of the test fixture, the Line calibration piece corresponds to the transmission state of the test fixture, and the Open calibration piece corresponds to the reflection state of the test fixture. According to the corresponding port positions, the Thru calibration piece, the Line calibration piece, and the Open calibration piece are connected to the network analyzer through cables in sequence. After the network analyzer performs a frequency sweep, the test result files of the three calibration pieces are obtained. When testing the Open calibration piece, the connection between port 1 of the Open calibration piece and the network analyzer is disconnected, and only port 2 is connected. The network analyzer performs a frequency sweep to obtain the test result. Then, the connection between port 2 of the Open calibration piece and the network analyzer is disconnected, and only port 1 is connected. The network analyzer performs a frequency sweep to obtain the test result. The test result files of the Thru calibration piece, the Line calibration piece, and the Open calibration piece obtained by the test are simulated to generate the S parameters of the three calibration pieces, which are expressed as After the test fixture is calibrated, the calibrated network analyzer is used to test the test fixture with the DUT installed. As shown in Figure 2, the DUT is fixed on the test fixture. The test fixture is provided with two electrodes for leading out the two ports of the DUT. The two ports are then connected to the network analyzer through cables. The network analyzer sweeps the connected DUT and the included test fixture to obtain the test results. Finally, combined with the S parameters Get the S parameters of the electronic components under test after de-embedding As shown in the following formula:

2. The electronic component S parameter testing method according to claim 1, characterized in that: The network analyzer settings include: 1) Set the frequency range and step size to be calibrated as needed; 2) Set the output power of the network analyzer during calibration, and after the setting is completed, check the box and turn on the power switch; 3) Set the intermediate frequency bandwidth of the network analyzer during calibration to a value between 100Hz-1KHz.

3. The electronic component S parameter testing method according to claim 1, characterized in that: Calibrate the network analyzer and cables. The specific calibration process is as follows: Step 31: Create a calibration model Edit the calibration box name and description; Set the connector type to TRL and set the frequency range; Add calibration parts and corresponding parameters; After editing is completed, the calibration parts box will generate the calibration parts box corresponding to the test fixture; Step 32: Instrument calibration Set the frequency range and IF bandwidth in the vector network analyzer; Select the calibration type; Connect the SHORT standard, LINE standard, and THRU standard to calibrate respectively; After the calibration is completed, the standing wave insertion loss will be reset to zero. If the zeroing state is not ideal, recalibration is required. Step 33: Set up the test interface Add a new test channel: Click Trace / Chan--Trace--New Trace, select S11, S22, S12, S21 and click OK; click Format to set the unit format.

4. The electronic component S parameter testing method according to claim 3, characterized in that: After the network analyzer is calibrated, keep the Thru standards at ports 1 and 2 connected to the network analyzer, create a new track on the network analyzer, and check S21 and S12 in the S parameters. If the tracks of the two are basically consistent and located near 0dB, and the maximum error range does not exceed ±0.05dB, the calibration result meets the requirements.

5. The electronic component S parameter testing method according to claim 4, characterized in that: Also includes: After the DUT test is completed, the S21 and S12 parameters of the Thru calibration component are tested again and compared with the S21 and S12 parameter curves obtained during the network analyzer calibration. If the trajectories of the two S21 and two S12 parameters are basically consistent and are located near 0dB, the drift error of this test process is small and the test is qualified.

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