CN112731020A

CN112731020A - Switching circuit, signal testing system and method

Info

Publication number: CN112731020A
Application number: CN202011521937.5A
Authority: CN
Inventors: 明慧; 李少昆
Original assignee: Nanchang Huaqin Electronic Technology Co ltd
Current assignee: Nanchang Huaqin Electronic Technology Co ltd
Priority date: 2020-12-21
Filing date: 2020-12-21
Publication date: 2021-04-30

Abstract

The application provides a switching circuit, a signal testing system and a method, wherein the switching circuit comprises: the output end of the first connector is connected with the input end of the second connector; the first connector is used for receiving the NVME4.0 signal and transmitting the NVME4.0 signal to the second connector; the second connector is used for converting the NVME4.0 signal into a PCIE4.0 signal and outputting the PCIE4.0 signal. The switching circuit receives the NVME4.0 signal through the first connector, transmits the NVME4.0 signal to the second connector, and then converts the NVME4.0 signal into a PCIE4.0 signal to be output, and conversion from the NVME4.0 signal to the PCIE4.0 signal is achieved.

Description

Switching circuit, signal testing system and method

Technical Field

The present disclosure relates to the field of electronic technologies, and in particular, to a switching circuit, a signal testing system and a signal testing method.

Background

With the development of science and technology, the transmission of high-speed signals such as NVME4.0, PCIE4.0 and the like is widely applied. In order to ensure the transmission quality of the signal, the performance of the signal is usually tested.

At present, a set of mature test fixtures and test methods have been formed for testing PCIE4.0 signals, but the test for NVME4.0 signals is still a blank, and meanwhile, there is no method or device for realizing conversion between NVME4.0 signals and PCIE4.0 signals, so that a user cannot accurately test NVME4.0 signals.

Disclosure of Invention

The application provides a switching circuit, a signal testing system and a signal testing method, which can realize the conversion from NVME4.0 signals to PCIE4.0 signals.

In a first aspect, the present application provides a patching circuit, comprising: the output end of the first connector is connected with the input end of the second connector.

The first connector is used for receiving NVME4.0 signals and transmitting the NVME4.0 signals to the second connector.

The second connector is used for converting the NVME4.0 signal into a PCIE4.0 signal and outputting the PCIE4.0 signal.

Optionally, the power loss of the switching circuit is smaller than a preset value.

Through this switching circuit, can the accuracy of signal test.

In a second aspect, the present application provides a signal testing system comprising: the switching circuit of any of claims 1-4, the device under test and the test device; the signal output end of the device to be tested is connected with the input end of the switching circuit, and the output end of the switching circuit is connected with the input end of the test device.

The device to be tested is used for outputting NVME4.0 signals.

The switching circuit is used for converting the NVME4.0 signal into a PCIE4.0 signal and transmitting the PCIE4.0 signal to the test equipment.

The test equipment is used for testing PCIE4.0 signals.

Optionally, the test equipment includes a PCIE4.0 test fixture and an oscilloscope.

The output end of the switching circuit is connected with the input end of the PCIE4.0 test fixture.

The output end of the PCIE4.0 test fixture is connected with an oscilloscope.

The oscilloscope is used for acquiring scattering parameters of the switching circuit and adjusting the loss of the switching circuit according to the scattering parameters so as to enable the loss of the switching circuit to be smaller than or equal to a preset value.

The system can transmit the PCIE4.0 signal output by the switching circuit to the oscilloscope through the PCIE4.0 test fixture according to the characteristic of the high-speed signal, so that the signal is reduced, and the accuracy of signal test is improved.

Optionally, the oscilloscope is specifically configured to perform de-embedding operation on the forwarding circuit according to the scattering parameter, and perform embedding operation on the forwarding circuit to adjust the loss of the forwarding circuit, so that the loss of the forwarding circuit is smaller than or equal to a preset value.

Through the system, the signal loss of the switching circuit can be adjusted, the loss of signals in the transmission process in a test system is adjusted, and the accuracy of NVME4.0 signal test is further improved.

Optionally, the method further includes: the electronic equipment is in communication connection with the oscilloscope.

The electronic equipment is used for acquiring scattering parameters of the switching circuit and sending the scattering parameters to the oscilloscope.

The system acquires the scattering parameters of the switching circuit by being deployed on the electronic equipment and sends the scattering parameters to the oscilloscope, so that the oscilloscope can more accurately adjust the signal loss of the switching circuit, further adjust the loss of signals in a transmission process in a test system, and further improve the accuracy of NVME4.0 signal test.

In a third aspect, the present application provides a signal testing method, which is applied to any one of the systems as provided in the second aspect or the alternatives of the second aspect, the method comprising:

and acquiring scattering parameters of the switching circuit.

And adjusting the loss of the switching circuit according to the scattering parameters so as to enable the loss of the switching circuit to be smaller than or equal to a preset value.

According to the signal testing method, the S parameter of the switching circuit is obtained, the loss of the switching circuit is adjusted according to the S parameter, so that the loss of the switching circuit is smaller than or equal to the preset value, the signal loss of the switching circuit can be eliminated, the signal loss of a signal testing system meets the requirement of a PCIE4.0 testing standard, and the accuracy of signal testing is improved.

Optionally, adjusting the loss of the switching circuit according to the scattering parameter so that the loss of the switching circuit is less than or equal to a preset value, including:

and according to the scattering parameters, performing de-embedding operation on the switching circuit.

And performing embedding operation on the switching circuit to adjust the loss of the switching circuit so that the loss of the switching circuit is less than or equal to a preset value.

According to the method, the de-embedding operation is carried out on the switching circuit according to the scattering parameters of the switching circuit, so that the signal loss caused by the connecting circuit can be eliminated; furthermore, the loss of the switching circuit can be controlled within a certain range by embedding the switching circuit, so that the signal loss in the whole signal testing system meets the standard loss requirement, and the accuracy of signal testing is improved.

In a fifth aspect, the present application provides an adapter card comprising a chip as provided in the fourth aspect.

The application provides a switching circuit, a signal testing system and a method, wherein the switching circuit comprises: the output end of the first connector is connected with the input end of the second connector. The first connector is used for receiving NVME4.0 signals and transmitting the NVME4.0 signals to the second connector. The second connector is used for converting the NVME4.0 signal into a PCIE4.0 signal and outputting the PCIE4.0 signal. The switching circuit receives the NVME4.0 signal through the first connector, transmits the NVME4.0 signal to the second connector, and then converts the NVME4.0 signal into a PCIE4.0 signal to be output, and conversion from the NVME4.0 signal to the PCIE4.0 signal is achieved.

Drawings

FIG. 1 is a schematic diagram of a patching circuit provided by the present application;

FIG. 2 is a schematic diagram of a signal testing system according to the present application;

FIG. 3 is a schematic diagram of another embodiment of a signal testing system provided herein;

FIG. 4 is a schematic diagram of another exemplary signal testing system provided herein;

fig. 5 is a schematic flowchart of a signal testing method provided in the present application.

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

Detailed Description

Reference will now be made in detail to the exemplary embodiments, examples of which are illustrated in the accompanying drawings. When the following description refers to the accompanying drawings, like numbers in different drawings represent the same or similar elements unless otherwise indicated. The implementations described in the exemplary embodiments below are not intended to represent all implementations consistent with the present disclosure. Rather, they are merely examples of apparatus and methods consistent with certain aspects of the present disclosure, as detailed in the appended claims.

In order to ensure the transmission quality of signals, especially high-speed signals, it is usually necessary to test the performance of the signals.

The PCIE4.0 signal and the NVME4.0 signal are common high-speed signals. Currently, for testing PCIE4.0 signals, the PCIE association has formed a set of mature test fixtures and test methods. When testing the PCIE4.0 signal output by the device to be tested, the user may use the PCIE4.0 test fixture proposed by the PCIE association and the corresponding test method to test the PCIE4.0 signal output by the device to be tested.

However, the test for the NVME4.0 signal is still blank at present, and there is no widely accepted test fixture and test method, so that the user cannot accurately test the NVME4.0 signal.

If the NVME4.0 signal can be converted into the PCIE4.0 signal, the PCIE4.0 signal obtained by converting the NVME4.0 signal can be tested by the test fixture and the test method for the PCIE4.0 signal, so that indirect testing of the NVME4.0 signal is realized. The problem that NVME4.0 signals cannot be tested in the prior art is solved.

Based on this, the application provides a switching circuit, including first connector and second connector, first connector output is used for the output connection of second connector, and first connector transmits the NVME4.0 signal received to the second connector, makes the second connector convert NVME4.0 signal into PCIE4.0 signal to output PCIE4.0 signal, has realized converting NVME4.0 signal into PCIE4.0 signal.

Fig. 1 is a schematic diagram of a switching circuit provided in the present application, and as shown in fig. 1, the switching circuit 10 includes: a first connector 101 and a second connector 102.

The output of the first connector 101 is connected to the input of the second connector 102.

The switching circuit is used for converting the first signal into a second signal. The first signal may be an NVME4.0 signal, and the second signal may be a PCIE4.0 signal.

Specifically, the first connector 101 is configured to receive NVME4.0 signals and transmit the NVME4.0 signals to the second connector 102. For example, the first connector 101 is used for receiving a clock signal of NVME4.0 and a 4-way data signal; and transmits the received clock signal and 4-way data signal to the second connector.

The second connector 102 is configured to convert the NVME4.0 signal into a PCIE4.0 signal, and output a PCIE4.0 signal. For example, the second connector converts the received NVME4.0 clock signal and 4-way data signal into corresponding PCIE4.0 signal, and outputs the signal.

Further, the first connector may be a standard interface connector corresponding to NVME4.0 signals.

The second connection may be a standard interface connector corresponding to a PCIE4.0 signal.

Based on this, the switching circuit can convert the NVME4.0 signal and output the converted NVME4.0 signal through the standard interface corresponding to the PCIE4.0 signal, so that the switching circuit can be connected to the standard test equipment corresponding to the PCIE4.0 signal, and the NVME4.0 signal is tested through the standard test equipment.

It should be noted that the specific models of the standard interface connector corresponding to the NVME4.0 signal and the standard interface connector corresponding to the PCIE4.0 signal may be selected according to actual situations, and the present application is not limited thereto.

Further, when the NVME4.0 signal needs to be tested, the NVME4.0 signal can be converted into the PCIE4.0 signal through the switching circuit, and then the PCIE4.0 signal obtained by converting the NVME4.0 signal is tested by using standard test equipment corresponding to the PCIE4.0 signal.

In order to ensure the accuracy of the PCIE4.0 signal test, the sum of the signal losses of the switching circuit and the standard test equipment corresponding to the PCIE4.0 signal cannot exceed 8db, and it is known that the loss of the standard test equipment corresponding to the PCIE4.0 signal is 5 db.

Therefore, in order to improve the accuracy of the signal test, the following options are selected: the power loss of the switching circuit is less than a preset value.

For example, the preset value may be 3 dB.

Specifically, in order to control the loss of the switching Circuit to be smaller than a preset value, corresponding limitations can be made when the Printed Circuit Board (PCB) of the switching Circuit is laid out and wired. Taking a 6-layer PCB as an example, the signal layers can be arranged at intervals to reduce the interference between signals and reduce the signal loss; wherein the 2 nd and 5 th layers can be set as ground layers, wherein the line width of the ground line can be set to 1.2 mil; the 4 th layer can be set as a power supply layer, wherein the line width of the power supply line can be set to be 1.2 mil; the 1 st layer can be set as a signal layer, and the line width of a corresponding signal line can be set to be 1.65 mil; the 3 rd layer can be set as a signal layer, and the line width of a corresponding signal line can be set to be 1.2 mil; the 6 th layer may be provided as a signal layer, and the line width of its corresponding signal line may be set to 1.65 mil.

The switching circuit provided by the application receives NVME4.0 signals through the first connector, and transmits the NVME4.0 signals to the second connector, and then converts the NVME4.0 signals into PCIE4.0 signals for output. Furthermore, the second connector can be connected with standard test equipment corresponding to the PCIE4.0 signal to test the NVME4.0 signal, so that the problem that the NVME4.0 cannot be tested in the prior art is solved.

Fig. 2 is a schematic structural diagram of a signal testing system provided in the present application, and as shown in fig. 2, the signal testing system includes: a switching circuit 21, a device under test 22 and a test device 23.

The switching circuit 21 may be the switching circuit in the embodiment shown in fig. 1.

The signal output end of the device under test 22 is connected with the signal input end of the switching circuit 21, and the signal output end of the switching circuit 21 is connected with the signal input end of the test device 23.

The through circuit 21 can transmit the signal to be tested output by the device under test 22 to the test device 23, so that the test device 23 can test the signal to be tested.

Specifically, the device under test 22 is configured to output an NVME4.0 signal.

The switching circuit 21 is configured to convert the NVME4.0 signal into a PCIE4.0 signal, and transmit the PCIE4.0 signal to the test device 23.

The test equipment 23 is used for testing PCIE4.0 signals.

That is, when the signal to be tested is an NVME4.0 signal, the adapting circuit 21 converts the NVME4.0 signal received from the device to be tested 22 into a PCIE4.0 signal, and transmits the signal to the test device 23, so that the test device tests the signal.

Based on the characteristics of the high-speed signal, in order to improve the accuracy of the signal test, fig. 3 is another schematic structural diagram of the signal test system provided in the present application, as shown in fig. 3, optionally, the test apparatus includes: PCIE4.0 test fixture 231 and oscilloscope 232.

The output terminal of the adapting circuit 21 is connected to the input terminal of the PCIE4.0 test fixture 231.

The output terminal of the PCIE4.0 test fixture 21 is connected to the oscilloscope 232.

The oscilloscope 232 is used to obtain scattering parameters, commonly referred to as S-parameters, of the through circuit 21; and according to the S parameter, the loss of the through circuit 21 is adjusted so that the loss of the through circuit 21 is less than or equal to a preset value.

Specifically, the S parameter of the adapting circuit 21 may be input through the interactive interface of the oscilloscope 232, or a file including the S parameter of the adapting circuit 21 may be input through the interactive interface of the oscilloscope 232, so that the oscilloscope obtains the S parameter of the adapting circuit 21.

In order to ensure the accuracy of the PCIE4.0 signal test, the test standard specifies that the sum of the signal loss of the switching circuit and the standard test device corresponding to the PCIE4.0 signal cannot exceed 8db, and the loss of the standard test device corresponding to the PCIE4.0 signal is known to be 5 db. Therefore, in order to improve the accuracy of the signal test, the preset value may be 3dB, that is, the oscilloscope 232 is used to obtain the scattering parameter of the through circuit 21, which is generally referred to as S parameter; and adjusts the loss of the through circuit 21 according to the S parameter so that the loss of the through circuit 21 is less than or equal to 3 dB.

Further, optionally, the oscilloscope 23 is specifically configured to perform de-embedding operation on the forwarding circuit 21 according to the S parameter, and then perform embedding operation on the forwarding circuit 21 to adjust the loss of the forwarding circuit 21, so that the loss of the forwarding circuit 21 is smaller than or equal to a preset value.

Specifically, the oscilloscope 23 is specifically configured to perform a de-embedding operation on the switching circuit 21 according to the S parameter, so as to eliminate loss of the switching circuit 21.

Then, the oscilloscope 23 is further configured to perform an embedding operation on the switching circuit 21 to embed a certain amount of loss, and further adjust the loss of the switching circuit 21 so that the loss of the switching circuit 21 is less than or equal to a preset value.

Further, for the S parameter of the adapter card, the S parameter of the adapter circuit can be obtained by analyzing the PCB diagram corresponding to the adapter circuit through the SI simulation tool.

For example, the SI simulation tool may be a High Frequency Structure Simulator (HFSS).

Generally, the SI simulation tool is deployed on an electronic device, such as a computer.

Based on this, optionally, fig. 4 is a schematic structural diagram of a signal testing system provided in the present application, and as shown in fig. 4, the signal testing system further includes, on the basis of the signal testing system shown in fig. 3: an electronic device 24.

Wherein the electronic device 24 is in communication connection with the oscilloscope 23.

The electronic device 24 is configured to obtain the S parameter of the switching circuit 21 and send the S parameter to the oscilloscope 23.

For example, the electronic device 24 may be in direct communication with the oscilloscope 23, such as via a wired connection or a wireless connection, for data transfer.

The electronic device 24 may also be indirectly connected to the oscilloscope 23 in a communication manner, for example, the electronic device 24 may be communicated with a mobile storage medium such as a usb disk, the S parameter of the switching circuit 21 is acquired and stored from the electronic device 24, and then the mobile storage medium such as the usb disk storing the S parameter of the switching circuit 21 is communicated with the oscilloscope 23, so that the oscilloscope 23 acquires the S parameter of the switching circuit 21.

The signal test system that this application passed through, NVME4.0 signal conversion that will await measuring equipment output is for PCIE4.0 signal through the switching circuit, and then tests this conversion PCIE4.0 signal that comes through the test equipment that the PCIE4.0 signal corresponds, has realized the test to the NVME4.0 signal of awaiting measuring equipment output, has overcome the difficult problem that can't test NVME4.0 signal among the prior art.

Fig. 5 is a schematic flowchart of a signal testing method provided in the present application, the signal testing method is applied to the signal testing system provided in the foregoing embodiment, as shown in fig. 5, the method includes:

s501, obtaining S parameters of the switching circuit.

Specifically, the S parameter of the through circuit can be obtained by an oscilloscope.

For example, the scattering parameters of the patch circuit may be input by a user via an interactive interface or an interactive interface of the oscilloscope.

When the signal testing system comprises the electronic equipment with the SI simulation tool, S parameters of the switching circuit can be obtained through the electronic equipment, and the electronic equipment is in communication connection with the oscilloscope, so that the electronic equipment transmits the scattering parameters to the oscilloscope.

S502, according to the S parameter, the loss of the switching circuit is adjusted so that the loss of the switching circuit is smaller than or equal to a preset value.

Specifically, one possible implementation manner of adjusting the loss of the through circuit according to the S parameter so that the loss of the through circuit is less than or equal to the preset value is as follows:

according to the S parameter, performing de-embedding operation on the switching circuit; and performing embedding operation on the switching circuit to adjust the loss of the switching circuit so that the loss of the switching circuit is less than or equal to a preset value.

For example, the oscilloscope performs a de-embedding operation on the switching circuit according to the S parameter to eliminate the loss of the switching circuit, then performs an embedding operation on the switching circuit to embed a certain amount of loss, and further adjusts the loss of the switching circuit so that the loss of the switching circuit is less than or equal to a preset value.

When the signal loss of the switching circuit is equal to the preset value, the present application further provides a signal testing method, which can be applied to the signal testing system provided in the above embodiment.

Specifically, when the NVME4.0 signal is tested by the signal testing system through the method, the signal is directly input into the oscilloscope through the oscilloscope test, the S parameter of the switching circuit does not need to be acquired, and the loss of the switching circuit is adjusted according to the S parameter.

Because, when the signal loss of the switching circuit is equal to the preset value, the total loss of the signals in the signal testing system meets the requirement of the PCIE4.0 signal test, so that the PCIE4.0 signal converted from the NVME4.0 signal can be tested through the PCIE4.0 standard testing device without performing de-embedding and embedding operations on the switching circuit, and further, the test on the NVME4.0 signal is indirectly realized.

The application also provides a chip, and the chip comprises any one of the switching circuits provided by the embodiments.

The chip can realize the signal testing method, and the content and the effect of the signal testing method can be referred to the embodiment part of the method, which is not described again.

The application also provides an adapter card which comprises the chip provided by the embodiment.

The adapter card can realize the signal testing method, and the content and the effect of the signal testing method can be referred to the embodiment part of the method, which is not described again.

Other embodiments of the disclosure will be apparent to those skilled in the art from consideration of the specification and practice of the disclosure disclosed herein. This application is intended to cover any variations, uses, or adaptations of the disclosure following, in general, the principles of the disclosure and including such departures from the present disclosure as come within known or customary practice within the art to which the disclosure pertains. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the disclosure being indicated by the following claims. It will be understood that the present disclosure is not limited to the precise arrangements described above and shown in the drawings and that various modifications and changes may be made without departing from the scope thereof. The scope of the present disclosure is limited only by the appended claims.

Claims

1. A patching circuit, comprising: the output end of the first connector is connected with the input end of the second connector;

the first connector is used for receiving NVME4.0 signals and transmitting the NVME4.0 signals to the second connector;

2. The patching circuit of claim 1, wherein a power loss of the patching circuit is less than a preset value.

3. A signal testing system, comprising: the patching circuit of claim 1 or 2, a device under test, and a test device; the signal output end of the device to be tested is connected with the input end of the switching circuit, and the output end of the switching circuit is connected with the input end of the test device;

the device to be tested is used for outputting NVME4.0 signals;

the switching circuit is used for converting the NVME4.0 signal into a PCIE4.0 signal and transmitting the PCIE4.0 signal to the test equipment;

the test equipment is used for testing the PCIE4.0 signal.

4. The system of claim 3, wherein the test equipment comprises a PCIE4.0 test fixture and an oscilloscope;

the output end of the switching circuit is connected with the input end of the PCIE4.0 test fixture;

the output end of the PCIE4.0 test fixture is connected with the oscilloscope;

5. The system of claim 4, wherein the oscillograph is specifically configured to perform a de-embedding operation on the transit circuit and a de-embedding operation on the transit circuit according to the scattering parameter to adjust the loss of the transit circuit to be less than or equal to a predetermined value.

6. The system of claim 4 or 5, further comprising: the electronic equipment is in communication connection with the oscilloscope;

7. A signal testing method applied to the system according to any one of claims 3 to 5, the method comprising:

acquiring scattering parameters of the switching circuit;

8. The method of claim 7, wherein the adjusting the loss of the switching circuit to be less than or equal to a predetermined value according to the scattering parameter comprises:

according to the scattering parameters, performing de-embedding operation on the switching circuit;

9. A chip comprising a through circuit as claimed in claim 1 or 2.

10. An adapter card comprising the chip of claim 9.