TVS test board, test method, and readable storage medium

Abstract

This application provides a TVS test board, a test method, and a readable storage medium. The TVS test board includes a control module, a voltage amplification module, a first scaling module, a second scaling module, a voltage divider module, a switching module, and M on / off units. Different on / off units among the M on / off units are used to connect different TVS diodes of the interface of the product under test (DUT), and the on / off units are used to control the connection and disconnection between the TVS diodes and the switching module. This TVS test board can simultaneously connect multiple DUT interfaces. Each DUT interface has multiple TVS diodes, and the TVS diodes of different DUT interfaces have different specifications. Even for the same DUT interface, there are multiple specifications of TVS diodes. The TVS board completes batch testing by sequentially testing each TVS diode of at least one DUT interface. The testing time is short, and there is no need to use a multimeter or oscilloscope. The process is simple, improving testing efficiency while reducing testing costs.

Description

Technical Field

[0001] This application relates to the field of electronic technology, and in particular to a TVS test board, a test method, and a readable storage medium. Background Technology

[0002] A transient voltage suppressor (TVS), also known as a TVS tube, is a high-efficiency transient overvoltage protection device, commonly used to suppress instantaneous overvoltages.

[0003] Typically, a TVS diode is connected in parallel with the protected circuit. When a surge voltage occurs in the protected circuit, the TVS diode quickly Zener breaks down, changing from a high-resistance state to a low-resistance state, thus shunting and clamping the surge voltage and preventing damage to components in the protected circuit. If the TVS diode fails, it will not provide protection and may even damage the equipment. Therefore, it is necessary to test the TVS diode. The industry uses a multimeter or oscilloscope to test the continuity of the TVS diode. During the test, the multimeter or oscilloscope is adjusted so that its two contacts are connected to the TVS diode to perform a continuity test in one direction. Then, the two contacts are swapped to perform a continuity test in the other direction.

[0004] However, different specifications of TVS diodes have different parameters and different testing requirements. A printed circuit board (PCB) usually has a variety of TVS diodes. Testing different specifications of TVS diodes by adjusting the output voltage of a multimeter or oscilloscope is a cumbersome process, inefficient and costly. Summary of the Invention

[0005] This application provides a TVS test board, a test method, and a readable storage medium. By using a TVS test board to test TVS tubes of different specifications, the TVS test board replaces expensive multimeters or oscilloscopes, the process is simple, and the test efficiency is improved while the test cost is reduced.

[0006] In a first aspect, embodiments of this application provide a TVS test board, comprising: a control module, a voltage amplification module, a first scaling module, a second scaling module, a voltage divider module, a switching module, and M on / off units. Different on / off units among the M on / off units are used to connect different TVS transistors of the interface of the product under test. The interface of the product under test is at least one, and the total number of TVS transistors of at least one interface of the product under test is ≤M, where M≥1. The on / off units are used to control the on / off connection between the TVS transistors and the switching module. At any given time, one on / off unit among the M on / off units is on, while the remaining on / off units are off. The switching module is used to control whether the TVS transistors are subjected to positive or negative testing.

[0007] The control module has at least a DAC pin, a first ADC pin, a second ADC pin, and N+1 input / output pins. The DAC pin is connected to the input terminal of the voltage amplification module, the first ADC pin is connected to the first terminal of the first scaling module, the second ADC pin is connected to the first terminal of the second scaling module, one of the N+1 input / output pins is connected to the switching module, and M of the remaining N input / output pins are respectively connected to different switching units in the M switching units, where M≤N;

[0008] The output terminal of the voltage amplification module is connected to the second terminal of the first scaling module and the first terminal of the voltage divider module.

[0009] The second end of the voltage divider module is connected to the second end of the second scaling module and the switching module.

[0010] Secondly, embodiments of this application provide a testing method applied to a TVS test board implemented as described in the first aspect or various possible implementations of the first aspect, the method comprising:

[0011] Determine the total number of TVS transistors and the TVS queue in at least one interface of the product under test, wherein the TVS queue is obtained by sorting the TVS transistors in the at least one interface of the product under test.

[0012] According to the order indicated by the TVS queue, each TVS tube in the TVS queue is tested sequentially;

[0013] After each TVS tube in the TVS queue is tested, the total number and the number of TVS tubes tested are used to determine whether the testing of all TVS tubes in the TVS queue is complete.

[0014] If the testing of each TVS tube in the TVS queue is not completed, continue testing the TVS tubes in the TVS queue until the testing of each TVS tube in the TVS queue is completed.

[0015] Thirdly, embodiments of this application provide a computer-readable storage medium storing computer instructions that, when executed by a processor, are used to implement the method described in the second aspect above or various possible implementations of the second aspect.

[0016] Fourthly, embodiments of this application provide a computer program product comprising a computing program, wherein when the computer program is executed by a processor, it implements the method described in the second aspect above or various possible implementations of the second aspect.

[0017] The TVS test board, test method, and readable storage medium provided in this application embodiment include a control module, a voltage amplification module, a first scaling module, a second scaling module, a voltage divider module, a switching module, and M on / off units. Different on / off units among the M on / off units are used to connect to different TVS diodes of the interface of the product under test (DUT). The on / off units control the connection between the TVS diodes and the switching module. At any given time, one on / off unit is on, while the others are off. The switching module controls whether the TVS diodes are tested in the forward or reverse direction. This TVS test board can simultaneously connect to multiple DUT interfaces. Each DUT interface has multiple TVS diodes, and the specifications of the TVS diodes on different DUT interfaces are different. Even for the same DUT interface, there are multiple specifications of TVS diodes. The TVS board completes batch testing by sequentially testing each TVS diode of at least one DUT interface. The testing time is short, and there is no need to use a multimeter or oscilloscope. The process is simple, improving testing efficiency while reducing testing costs. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1A This is a schematic diagram of a scenario for the testing method provided in the embodiments of this application;

[0020] Figure 1B This is a schematic diagram of the structure of the TVS test board provided in the embodiments of this application;

[0021] Figure 2A This is a schematic diagram of the TVS test board provided in this embodiment testing the TVS tubes of two product interfaces under test;

[0022] Figure 2BThis is a schematic diagram of the TVS test board used to test the TVS tube of the HDMI interface according to an embodiment of this application;

[0023] Figure 2C This is a schematic diagram of the TVS tube of the test port of the TVS test board provided in the embodiment of this application;

[0024] Figure 2D This is a schematic diagram of the TVS test board provided in this application for testing the TVS tube of the VGA interface;

[0025] Figure 3 This is a partial circuit example diagram of the TVS test board provided in the embodiments of this application;

[0026] Figure 4 This is a flowchart of the testing method provided in the embodiments of this application;

[0027] Figure 5 This is another flowchart of the testing method provided in the embodiments of this application;

[0028] Figure 6 This is another flowchart of the testing method provided in the embodiments of this application. Detailed Implementation

[0029] A TVS diode is an overvoltage protection device with bidirectional voltage regulation and bidirectional negative resistance characteristics, similar to a varistor. TVS diodes are used in various AC and DC power supply circuits to suppress transient overvoltages. When a surge voltage occurs in the protected circuit, the TVS diode quickly breaks down through a Zener diode, changing from a high-resistance state to a low-resistance state, thus shunting and clamping the surge voltage, protecting the components in the circuit from damage. Clamping refers to fixing the voltage across the TVS diode within a relatively small range. TVS diodes include unidirectional and bidirectional types. Unidirectional TVS diodes are designated with the suffix "A," while bidirectional TVS diodes are designated with the suffix "CA." The characteristics of a unidirectional TVS diode are similar to those of a Zener diode, while the characteristics of a bidirectional TVS diode are equivalent to two Zener diodes connected in reverse series.

[0030] Typically, the TVS diode on the PCB board is connected in parallel with the circuit being protected. If the TVS diode fails, it will not provide protection, causing abnormalities in the protected circuit and potentially damaging the equipment. Therefore, the TVS diodes on the PCB board of the equipment need to be tested before leaving the factory. Furthermore, even after the equipment has left the factory and is used by the user, the TVS diodes still need to be tested to repair the equipment in case of malfunction.

[0031] The two most common testing methods for TVS diodes are as follows:

[0032] Method 1: Use a multimeter or oscilloscope to test the continuity of the TVS diode. In this method, connect the two contacts of the multimeter or oscilloscope to the TVS diode to perform a continuity test in one direction. Then, interchange the two contacts to perform a continuity test in the other direction. Because there are many types of TVS diodes, and different specifications have different performance parameters, a PCB board often contains multiple specifications of TVS diodes. Therefore, each time a TVS diode is tested, the output voltage of the multimeter or oscilloscope needs to be adjusted according to the performance parameters of the TVS diode to meet the testing requirements.

[0033] Obviously, method one requires manual replacement of contacts for bidirectional testing and manual setting of multiple output voltage levels to determine whether the TVS tube is working properly. The operation is cumbersome, labor costs are high, and oscilloscopes are expensive, which further increases the testing cost.

[0034] Method 2: Build a test circuit and use the test circuit to test the TVS diode.

[0035] In this method, a test circuit with an indicator light is built based on the performance parameters of the TVS diode. The on / off state of the indicator light determines whether the TVS diode is conducting, making the test method simple. However, one test circuit can only test one type of TVS diode, while PCB boards often have multiple types of TVS diodes. Therefore, a separate test circuit needs to be built for each type of TVS diode, resulting in high testing costs.

[0036] Moreover, the two test methods mentioned above only test the continuity of the TVS diode, without distinguishing the clamping voltage and maximum current of the TVS diode, resulting in low test quality.

[0037] Based on this, embodiments of this application provide a TVS test board, a test method, and a readable storage medium. By using a TVS test board to test TVS tubes of different specifications, the TVS test board replaces expensive multimeters or oscilloscopes, simplifying the process and improving test efficiency while reducing test costs.

[0038] In this embodiment, the TVS diode to be tested is a TVS diode on the PCB board of the product under test. The product under test includes, but is not limited to, smart interactive flat panels, mobile phones, tablets, computers, televisions, virtual reality (VR) terminal devices, augmented reality (AR) terminal devices, wireless terminals in industrial control, wireless terminals in self-driving vehicles, wireless terminals in remote medical surgery, wireless terminals in smart grids, personal digital assistants (PDAs), in-vehicle devices, wearable devices, servers, etc. The product under test has interfaces, and a large number of TVS diodes are arranged in the circuit of the interface of the product under test.

[0039] Taking a smart interactive flat panel as an example, the PCB board of a smart interactive flat panel has many interfaces and plugs, including but not limited to communication interfaces and plugs. TVS diodes are installed in the circuits of these interfaces and plugs to prevent excessive external voltage from damaging the PCB board. Communication interfaces include, but are not limited to: Universal Serial Bus (USB) interfaces, Ethernet ports, High Definition Multimedia Interface (HDMI) interfaces, and Video Graphics Array (VGA) interfaces. USB interfaces include USB 2.0 interfaces and USB 3.0 interfaces. TVS diodes are installed in the circuits of these interfaces under test. For example, a USB 2.0 interface has 4 TVS diodes (also called a 4-channel TVS diode interface), a USB 3.0 interface has 8 TVS diodes, an HDMI interface has 15 TVS diodes, an Ethernet port has 4 TVS diodes, and a VGA interface has 11 TVS diodes. Plugs include, but are not limited to, XH2.54 plugs.

[0040] In this embodiment, a TVS test board is used to test the TVS diodes at the interface of the product under test. Besides testing the continuity of the TVS diodes, the operating or non-operating state of the TVS diode is determined based on the maximum value of a first voltage and the clamping voltage range of the TVS diode. Furthermore, when determining whether the TVS diode is qualified, the voltage divider current and the maximum current of the TVS diode are compared. The first voltage is also called the conduction voltage, and the voltage divider current is also called the conduction current. Therefore, this embodiment not only tests the continuity of the TVS diode but also determines the conduction voltage and conduction current.

[0041] In this embodiment, multiple product-under-test (DUT) interfaces can be inserted into the TVS test board at once via an adapter cable. After starting the test, the TVS diodes of each DUT interface are tested sequentially. The following describes the TVS test board and testing method described in this embodiment using the DUT interface as a communication interface as an example. For illustrative examples, please refer to... Figure 1A .

[0042] Figure 1A This is a schematic diagram of a test method provided in an embodiment of this application. Please refer to... Figure 1A When using the TVS test board 100 to test the TVS diodes on the interface of the product under test (DUT) on the PCB board 200, the TVS test board 100 and the DUT interface are connected via adapter cable 300. For example, the test board 100 is connected to the VGA interface via adapter cable 300, and to the USB 2.0 interface via another adapter cable 300. The TVS test board 100 then tests 15 TVS diodes. These 15 TVS diodes include 11 for the VGA interface and 4 for the USB 2.0 interface.

[0043] The working principle of a TVS diode is as follows: The TVS diode is connected in parallel with the circuit being protected. When the voltage across the TVS diode exceeds its clamping voltage, the TVS diode turns on and enters its working state. It diverts most of the current to ground through its low impedance, and the voltage across the TVS diode is clamped at a fixed value, preventing damage to the downstream protected circuit due to overvoltage. When the overvoltage disappears, the TVS diode switches from its operating state to its non-operating state. At this time, the TVS diode does not activate, and the circuit returns to normal. This operating state is also called the protection state or clamping state.

[0044] Below, based on Figure 1A The scenario shown and the working principle of the TVS diode are explained in detail to illustrate the TVS test board described in the embodiments of this application. For example, please refer to... Figure 1B .

[0045] Figure 1B This is a schematic diagram of the structure of the TVS test board provided in an embodiment of this application. Please refer to... Figure 1BThe TVS test board 100 provided in this application embodiment includes: a control module 11, a voltage amplification module 12, a first scaling module 13, a second scaling module 14, a voltage divider module 15, a switching module 16, and M on / off units 17. Different on / off units 17 among the M on / off units 17 are used to connect different TVS diodes of the interface of the product under test. The product under test has at least one interface, and the total number of TVS diodes of at least one interface of the product under test is ≤M, where M≥1. The on / off units 17 are used to control the connection and disconnection between the TVS diodes and the switching module 16. At any given time, one on / off unit 17 of the M on / off units 17 is on, while the remaining on / off units 17 are off. The switching module 16 is used to control whether the TVS diodes are subjected to positive or negative testing.

[0046] Please refer to Figure 1B The control module 11 has at least a DAC pin, a first ADC pin, a second ADC pin, and N+1 input / output pins. The DAC pin is as follows: Figure 1B In DAC_0, the first ADC pin is as follows: Figure 1B In the ADC_0, the second ADC pin is as follows: Figure 1B ACD_1 in the example. Input / output pins, such as general-purpose input / output (GPIO), N+1 input / output pins, such as... Figure 1B As shown in the diagram, GPIO_0 to GPIO_N are connected to the input terminals of voltage amplification module 12, the first ADC pin is connected to the first terminal of the first scaling module 13, the second ADC pin is connected to the first terminal of the second scaling module 14, one of the N+1 input / output pins is connected to switching module 16, and M of the remaining N input / output pins are connected to different switching units 17 in the M switching units 17, where M ≤ N. For example, the input / output pin connected to switching module 16 is GPIO_0, and GPIO_1 to GPIO_M are connected to switching units 1 to M, respectively. The connection relationships of GPIO_0 to GPIO_N are not shown in the diagram.

[0047] Figure 1B In the process, the output terminal of the voltage amplification module 12 is connected to the second terminal of the first scaling module 13 and the first terminal of the voltage divider module 15; the second terminal of the voltage divider module 15 is connected to the second terminal of the second scaling module 14 and the switching module 16.

[0048] Please refer to Figure 1BMultiple switching units 17 form multiple sockets. For example, M=20, meaning there are 20 switching units 17 in total. Every four switching units 17 form one socket, which is used to connect to the interface of the product under test (DUT) via adapter cables. Since one switching unit 17 can be considered as one test channel, the sockets formed by switching units 1-4 are also called channel 1-4 sockets. Similarly, the sockets formed by switching units 5-8 are also called channel 5-8 sockets, and so on. The sockets are used to connect to the interface of the DUT via adapter cables. The circuit board of the DUT interface has a TVS to be tested. For an example, please refer to... Figures 2A to 2D .

[0049] Figure 2A This is a schematic diagram of the TVS test board provided in this embodiment testing the TVS tubes of two product interfaces under test. Figure 2A In the test setup, one end of adapter cable 300 is inserted into the corresponding sockets for channels 1-4, and the other end is connected to a USB 2.0 interface, which has 4 TVS diodes. Another adapter cable 300 is inserted into sockets for channels 5-8 and 9-12, and the other end is connected to a USB 3.0 interface, which has 8 TVS diodes. After starting the test, the TVS test board tests each of the 12 TVS diodes sequentially.

[0050] It should be noted that, although Figure 2A This example illustrates the use of a USB 2.0 interface and a USB 3.0 interface simultaneously connected to the TVS test board. However, this embodiment is not limited to this. When multiple product-under-test (DUT) interfaces are simultaneously connected to the TVS test board, the number of DUT interfaces is ≥2, such as 2, 3, or 4, and the types of DUT interfaces are the same; or, the multiple DUT interfaces include two or more types of DUT interfaces. For example, two DUT interfaces are simultaneously connected to the TVS test board, both of which are USB 2.0 interfaces and both are USB 3.0 interfaces, or one is a USB 2.0 interface and the other is an HDMI interface. Another example is three DUT interfaces simultaneously connected to the TVS test board: a USB 2.0 interface, an Ethernet port, and a VGA interface.

[0051] Using this approach, the TVS test board can simultaneously establish connections with multiple different types of product-under-test interfaces. After starting the test, the TVS diodes on these product-under-test interfaces are automatically tested sequentially without the need for manual adjustment of the oscilloscope, etc. The test method is simple and fast, thus improving the efficiency of TVS diode testing.

[0052] Figure 2B This is a schematic diagram of the TVS test board used to test the TVS tube of the HDMI interface, provided in an embodiment of this application. Figure 2BIn the middle, one end of the adapter cable 300 is inserted into the channel 1-4 socket, channel 5-8 socket, channel 9-12 socket, and channel 13-16 socket, and the other end is connected to the HDMI interface, which has 15 TVS tubes.

[0053] It's understandable that since the HDMI interface has 15 TVS diodes, and the channel sockets (channels 1-4, 5-8, 9-12, and 13-16) have a total of 16 channels, meaning the HDMI interface corresponds to 16 on / off units, the 16th channel is empty and not connected to any TVS diode.

[0054] Figure 2C This is a schematic diagram of the TVS tube of the test port of the TVS test board provided in the embodiment of this application. Figure 2C In the middle, one end of the adapter cable 300 is inserted into the channel 1-4 socket, and the other end is connected to the network port, which has 4 TVS tubes.

[0055] Figure 2D This is a schematic diagram of the TVS test board provided in this application for testing the TVS tube of the VGA interface. Figure 2D In the middle, one end of the adapter cable 300 is inserted into the channel 1-4 sockets, channel 5-8 sockets, and channel 9-12 sockets, and the other end is connected to the VGA interface, which has 11 TVS diodes. Figure 2B similar, Figure 2D In the middle, the 12th channel is empty, meaning it is not connected to any TVS tube.

[0056] It should be noted that the adapter cable in this embodiment is related to the interface of the product under test. For example, if one end of the adapter cable is a plug for inserting into the socket of the TVS test board, and the other end is a USB 2.0 plug, then this adapter cable is used to connect the TVS test board and the USB 2.0 interface.

[0057] For example, if one end of the adapter cable is a plug for inserting into the socket of the TVS test board, and the other end is a network port plug, then this type of adapter cable is used to connect the TVS test board and the network port.

[0058] Below, in Figures 1A to 2D Based on this, the structure and working principle of the TVS test board described in the embodiments of this application will be explained in detail.

[0059] Figure 3 This is a partial circuit example diagram of the TVS test board provided in this application embodiment. This TVS test board allows for the sequential testing of multiple TVS diodes of different specifications. Please refer to... Figure 3The control module 11 is a microcontroller. The analog-to-digital converter (ADC) uses two sampling channels with a 12-bit sampling precision. The ADC data range is 0-4095, and the input range is 0-3.3V. It uses Direct Memory Access (DMA) for continuous sampling. The digital-to-analog converter (DAC) uses 12-bit digital data conversion. The DAC data range is 0-4095, and the output range is 0-3.3V. It uses DMA for continuous output.

[0060] Please refer to Figure 3 The amplification factor of the voltage amplification module 12 is y0, such as 20, 25, etc., which can be set according to actual needs.

[0061] The first scaling module 13 includes resistors R21, R22 and R23, etc. One end of R23 is connected to the first ADC pin, and the other end is connected to R22 and R21. One end of R22 is grounded, and one end of R21 is connected to the output terminal of the voltage amplification module 12.

[0062] The second scaling module 14 includes resistors R31, R32 and R33, etc. One end of R33 is connected to the second ADC pin, and the other end is connected to R32 and R31. One end of R32 is grounded, and one end of R31 is connected to the output terminal of the voltage divider module 15.

[0063] The voltage divider module 15 includes at least a resistor R11, and the voltages across the voltage divider module 15 are a first voltage V1 and a second voltage V2, respectively.

[0064] The switching module 16 includes at least an intermediate relay K0, which has 6 contacts: contact 2, contact 3, contact 4, contact 5, contact 6 and contact 7, used to control the positive or negative test of the TVS tube.

[0065] In the M switching units, each switching unit contains at least an intermediate relay, as shown by K1 to KM in the figure. The intermediate relays are used to control the switching of the TVS diode and the switching module 16. Taking intermediate relay K1 as an example, when contacts 3 and 5 of intermediate relay K1 are connected, and contacts 6 and 7 are connected, the TVS diode on the interface of the switching module 16 and the product under test is disconnected; when contacts 3 and 4 of intermediate relay K1 are connected, and contacts 5 and 6 are connected, the switching module 16 and the TVS diode on the interface of the product under test form a closed loop.

[0066] Furthermore, when the switching module 16 is connected to the TVS tube, and when contacts 3 and 4, and contacts 5 and 6 of the intermediate relay K0 of the switching module 16 are turned on, the switching module 16 is in positive mode. At this time, the current flows from the positive test pin of the TVS tube to the negative test pin, thereby realizing the positive test of the TVS tube.

[0067] Please refer to Figure 3 The control module 11 has at least N+1 input / output pins, as shown in the figure (GPIO_0-GPIO_N), where M≤N. M of these input / output pins are connected to M on / off units to control the on / off state of each unit. When the switching module 16 is connected to the TVS diode, and when contacts 3 and 5, and contacts 6 and 7 of the intermediate relay K0 of the switching module 16 are closed, the switching module 16 is in negative mode. At this time, current flows from the negative test pin of the TVS diode to the positive test pin, thus achieving negative testing of the TVS diode.

[0068] Figure 3 The M TVS diodes in the diagram represent at least one TVS diode for the interface of the product under test (DUT), and the total number of TVS diodes for at least one DUT interface is M. The output pins are also connected to resistors, etc. Taking GPIO_1 as an example, GPIO_ is connected to resistor R1, K1, and a 5V power supply, etc.

[0069] It should be noted that, Figure 3 For clarity, intermediate relays K0 to KN are drawn after the corresponding input and output pins. In fact, K0 is the intermediate relay in switching module 16, and K1 to KM are the intermediate relays in the corresponding switching units of M switching units, and do not represent new intermediate relays.

[0070] Please refer to Figure 3 The control module 11 outputs a voltage, referred to as the output voltage V0, through the DAC pin. This output voltage V0 is amplified by the voltage amplification module 12 to generate a first voltage V1. The first voltage V1 is then connected back to the first ADC pin of the control module 11 via the first scaling module 13. The control module 11 acquires the voltage at the first ADC pin to obtain the first measured voltage. The scaling factor of the first scaling module 13 is y1, which can be, for example, 34, and can be set according to actual needs.

[0071] Please refer to Figure 3 Because of the voltage divider module 15, the first voltage is reduced to the second voltage V2 after passing through the voltage divider module 15. The second voltage V2 is then connected back to the second ADC pin of the control module 11 via the second scaling module 14. The control module 11 acquires the voltage of the second ADC pin to obtain the second measured voltage. The scaling factor of the second scaling module 14 is y2, such as 34, which can be set according to actual needs.

[0072] The intermediate relay K0 in the switching module 16 is controlled by GPIO_0 to control the mode of the switching module 16. The switching module 16 has two modes: positive mode and negative mode.

[0073] Each switching unit 17 has an intermediate relay controlled by a corresponding GPIO. Taking the switching unit 17 with intermediate relay K2 as an example, intermediate relay K2 is controlled by GPIO_2. When contacts 3 and 4 of intermediate relay K2 are closed, and contacts 5 and 6 are also closed, intermediate relay K2 is said to be closed, and the TVS diode can be tested, such as for positive and negative tests. When contacts 3 and 5 of intermediate relay K2 are closed, and contacts 6 and 7 are also closed, intermediate relay K2 is said to be open, and the TVS diode cannot be tested.

[0074] The following is a specific example illustrating the testing principle of the TVS test board provided in this application.

[0075] Taking the testing of TVS diode 1, which is a bidirectional TVS diode, as an example, the clamping voltage of the bidirectional TVS diode is represented by V4, with a clamping voltage range of 31.10V-34.4V and a maximum current of 1 mA. The voltage drop of the voltage divider module 15 is 0.8V. During the forward test, when the control module 11 controls the contacts 3 and 4 of the intermediate relay K0 to be turned on, and contacts 5 and 6 to be turned on; moreover, the control module 11 controls the contacts 3 and 4 of the intermediate relay K1 to be turned on, and contacts 5 and 6 to be turned on. At the same time, the control module 11 controls the contacts 3 and 5 of the intermediate relays K2 to KM to be turned on, and contacts 6 and 7 to be turned on, thereby disconnecting the switching unit 2-switching unit M.

[0076] Subsequently, the control module 11 determines the starting voltage at the output terminal of the voltage amplification module 12 according to the test requirements, and controls the DAC pin to output an output voltage V0 to start the test. After the test is completed, the starting voltage is increased according to the increase magnitude of the starting voltage until the entire test is completed. The starting voltage, for example, is 5V, the increase magnitude is for example, 5V, and the maximum voltage is for example, 60V, which can be set according to the clamping voltage range of the TVS diode, etc.

[0077] According to the working principle of a TVS diode, when the second voltage V2, i.e., the voltage at the output of voltage divider module 15, is lower than the maximum value of the clamping voltage range, the circuit protected by the TVS diode is in normal operation. Therefore, the voltage difference between the first voltage V1 and the second voltage V2 should be less than the voltage drop of voltage divider module 15. The voltage drop of voltage divider module 15 depends on resistor R11, and is, for example, 0.8V. When the second voltage V2 is higher than the maximum value of the clamping voltage range, the TVS diode is in operation, thus keeping the second voltage V2 within the clamping voltage range.

[0078] Furthermore, the voltage divider current I2 can be calculated based on the first voltage V1 and the second voltage V2:

[0079] I2=(V1-V2) / R11.

[0080] R11 can be, for example, 62000, etc., but this application does not limit the implementation.

[0081] After the control module 11 of the TVS test board determines the first voltage V1, the second voltage V2 and the voltage divider current I2, it can perform a continuity test on the TVS transistor based on the first voltage V1, the second voltage V2 and the voltage divider current I2, and make a judgment on the first voltage V1, the second voltage V2 and the voltage divider current I2, thereby realizing the judgment on the conduction voltage and conduction current of the TVS transistor.

[0082] The TVS test board provided in this application includes a control module, a voltage amplification module, a first scaling module, a second scaling module, a voltage divider module, a switching module, and M on / off units. Different on / off units among the M units are used to connect to different TVS diodes of the interface of the product under test (DUT). The on / off units control the connection between the TVS diodes and the switching module. At any given time, one on / off unit is on, while the others are off. The switching module controls whether the TVS diodes are tested in the forward or reverse direction. This TVS test board can simultaneously connect to multiple DUT interfaces. Each DUT interface has multiple TVS diodes, and the specifications of the TVS diodes on different DUT interfaces are different. Even for the same DUT interface, there are multiple specifications of TVS diodes. The TVS board completes batch testing by sequentially testing each TVS diode of at least one DUT interface. The testing time is short, and there is no need to use a multimeter or oscilloscope. The process is simple, improving testing efficiency while reducing testing costs.

[0083] Based on the aforementioned TVS test board, this application embodiment also provides a test method applied to the aforementioned TVS test board. The test method provided in this application embodiment will be described in detail below. For example, please refer to... Figure 4 .

[0084] Figure 4 This is a flowchart of the testing method provided in this application embodiment. The execution subject of this embodiment is a TVS test board. This embodiment includes the following steps:

[0085] 401. Determine the total number of TVS transistors and the TVS queue in at least one interface of the product under test, wherein the TVS queue is obtained by sorting the TVS transistors in the at least one interface of the product under test.

[0086] Please refer to Figures 1A-3When testing TVS, connect the TVS test board and the interface of the product under test using an adapter cable. For example, if you need to test a TVS tube with a USB 2.0 interface and a TVS tube with a VGA interface, connect the USB 2.0 interface to the TVS test board using an adapter cable, and connect the VGA interface to the TVS test board using another adapter cable.

[0087] For example, if you need to test a TVS diode with a USB 3.0 interface, you can connect the USB 3.0 interface and the TVS test board using an adapter cable.

[0088] For example, if you need to test a TVS tube with two network ports, you can connect the network ports and the TVS test board using two adapter cables respectively.

[0089] In this embodiment, the TVS test board tests all TVS diodes on all interfaces of the product under test (DUT) by default. The TVS test board is connected to at least one DUT interface via an adapter cable; therefore, the total number of TVS diodes is the sum of the number of TVS diodes on at least one DUT interface. For example, both USB 2.0 and USB 3.0 interfaces are connected to the TVS test board via adapter cables. The four TVS diodes of the USB 2.0 interface correspond to intermediate relays K1 to K4, and the eight TVS diodes of the USB 3.0 interface correspond to intermediate relays K5 to K12, for a total of 12 TVS diodes.

[0090] Optionally, the TVS test board may have a serial port, allowing testers to specify which TVS diodes need to be tested and which do not. Continuing with the previous example, the user can configure the serial port to skip testing the TVS diodes controlled by K3 and K10. During testing, the TVS test board will skip the TVS diodes corresponding to K3 and K10.

[0091] In this embodiment, the TVS test board can flexibly determine the test sequence. In one approach, the TVS test board tests M TVS transistors sequentially from K1 to KM, with the test sequence being the same as the numbering sequence of the intermediate relays and also the arrangement sequence of the input / output pins.

[0092] In another approach, the TVS test board determines the testing order of each TVS transistor based on the serial port input.

[0093] 402. Test each TVS tube in the TVS queue in sequence according to the order indicated by the TVS queue.

[0094] For each TVS in the TVS queue, the TVS test board tests it according to the test mode of that TVS tube. For bidirectional TVS tubes, the total duration of the positive and negative tests does not exceed 1 second; for unidirectional TVS tubes, the duration of the positive or negative test does not exceed 0.5 seconds.

[0095] 403. After each TVS tube in the TVS queue is tested, determine whether the testing of all TVS tubes in the TVS queue is completed based on the total number and the number of TVS tubes tested. If the testing of all TVS tubes in the TVS queue is not completed, proceed to step 402; if the testing of all TVS tubes in the TVS queue is completed, then end.

[0096] After testing each TVS diode, the TVS test board increments the count of tested TVS diodes by 1, thus accumulating the total number of tested TVS diodes. Then, the TVS test board compares the number of tested TVS diodes with the total number. If the number of tested TVS diodes is less than the total number, it means there are still untested TVS diodes that need to be tested; if the number of tested TVS diodes equals the total number, the testing is complete.

[0097] The testing method provided in this application involves a TVS test board determining the total number of TVS diodes to be tested and the TVS queue. Following the order indicated by the TVS queue, each TVS diode is tested sequentially. After each TVS diode is tested, the number of tested TVS diodes is accumulated and compared with the latest number. If the testing of all TVS diodes in the TVS queue is not completed, the testing continues until all TVS diodes in the queue are tested. This approach is advantageous because the TVS diodes in the TVS queue originate from at least one interface of a product under test (DUT), which is connected to the TVS test board via an adapter cable. Each DUT interface has multiple TVS diodes, and the specifications of the TVS diodes differ between different DUT interfaces. Even within the same DUT interface, multiple specifications of TVS diodes may exist. By sequentially testing each TVS diode of at least one DUT interface, the TVS board eliminates the need for a multimeter or oscilloscope, simplifying the process and improving testing efficiency while reducing testing costs.

[0098] Optionally, in the above embodiments, the test parameters are used to indicate the test mode. The test mode includes any one of the following: shutdown test, bidirectional test, and unidirectional test. The bidirectional test includes positive test and negative test. When the test mode is that the TVS test board tests each TVS tube in the TVS queue in the order indicated by the TVS queue, when it is the i-th TVS tube's turn, the TVS test board obtains the test parameters of the i-th TVS tube and tests the i-th TVS tube according to the test parameters. When the test mode is bidirectional test or unidirectional test, the test parameters are also used to indicate the voltage drop of the voltage divider module, the clamping voltage range and maximum current of the TVS tube, the starting voltage of the output terminal of the voltage amplification module, the growth amplitude of the starting voltage, and the maximum voltage of the output terminal of the voltage amplification module, where 1 ≤ i ≤ total number and is an integer.

[0099] For example, the TVS test board communicates with a serial port tool. Users can use the serial port tool to specify which TVS diodes need to be tested and which do not. For instance, there are M TVS diodes in total. M=15, including 4 TVS diodes for the USB 2.0 interface and 11 TVS diodes for the VGA interface. The intermediate relays in the on / off units corresponding to these TVS diodes are K1 to KM. By default, all TVS diodes are tested. When users do not want to test certain TVS diodes, they can specify which TVS diodes do not need to be tested via the serial port, such as not testing the TVS diodes corresponding to K2 and T10. During subsequent sequential testing, the TVS test board will skip the TVS diodes corresponding to K2 and T10.

[0100] When testing the i-th TVS diode, the TVS test board acquires the test parameters for the i-th TVS diode. The test parameters include:

[0101] a. Test mode.

[0102] The test modes include any one of the following: shutdown test, bidirectional test, and unidirectional test. A shutdown test means the TVS diode is not tested. A bidirectional test includes positive and negative tests. A unidirectional test is either a positive or negative test, depending on the wiring.

[0103] b. Voltage drop of the voltage divider module.

[0104] Please refer to Figure 3 The voltage drop of the voltage divider module is the voltage difference between the first voltage V1 and the second voltage V2, and it is related to the specifications of the TVS diode. For example, TVS diode 1 is a bidirectional diode with a clamping voltage V4 of 15.60-17.20V, a maximum current of 5mA, and a voltage drop of 0.8V.

[0105] c. Clamping voltage range and maximum current of the TVS diode.

[0106] In the embodiments of the present application, the clamping voltage ranges and the maximum currents of TVS tubes with different specifications are different. For example, for a bidirectional TVS tube of one specification, the clamping voltage range is 15.60 - 17.20V and the maximum current is 5mA. For an unidirectional TVS tube of another specification, the clamping voltage range is 20.00 - 22.1V and the maximum current is 4mA.

[0107] d. Starting voltage, growth amplitude, maximum voltage.

[0108] In the embodiments of the present application, the starting voltage, growth amplitude, maximum voltage are related to the specification of the TVS tube. For example, TVS tube 1 is a bidirectional tube, the clamping voltage V4 is 15.60 - 17.20V, the maximum current is 5mA, the starting voltage V10 = 5V, the growth amplitude V11 = 5V, and the maximum voltage V12 = 60V.

[0109] Adopting this solution, the TVS test board obtains the test parameters for each TVS tube and tests the TVS tube according to the test parameters, achieving the purpose of improving the measurement accuracy.

[0110] Optionally, in the embodiments of the present application, for each TVS tube, multiple rounds of tests are required. The number of test rounds is related to the starting voltage at the output end of the starting voltage amplification module, the growth amplitude of the starting voltage, and the maximum voltage at the output end of the voltage amplification module. The starting voltage, growth amplitude, and maximum voltage are all obtained through serial communication. For example, the test parameters of the i-th TVS tube indicate that the starting voltage V10 = 5V, the growth amplitude V11 = 5V, and the maximum voltage V12 = 60V. It can be seen from this that the number of test rounds for a TVS tube is: 60 / 5 = 12 rounds. Therefore, the number of tests for the i-th TVS tube is 12 times. If each test passes, it means that the i-th TVS tube is qualified and has no faults. If a certain test fails, the test of the i-th TVS tube is stopped, and the i-th TVS tube is unqualified. After that, the test of the (i + 1)-th TVS tube is started.

[0111] Taking the forward test as an example, when the TVS test board performs the first round of test on the i-th TVS tube, the TVS test board determines the target value of the voltage amplification module according to the starting voltage. Then, the TVS test board determines the output voltage of the DAC pin according to the target value and controls the DAC pin to output this output voltage so that the TVS test board starts the first round of test.

[0112] For example, in the first round of testing, the TVS test board uses the initial voltage V10 as the target value of the first voltage V1, and determines the output voltage V0 of the DAC pin based on the target value, where V0 = V1 / y0. Then, the DAC pin outputs this output voltage V0, thereby initiating the first round of testing for the i-th TVS transistor. After the test starts, the TVS test board controls the on / off unit of the i-th TVS transistor to conduct, so that the i-th TVS transistor and the switching module are connected. Please refer to... Figure 3 Taking the i-th TVS diode as TVS diode 1 as an example, the TVS test board controls the intermediate relay K1 to conduct through GPIO_1, thereby enabling the i-th TVS diode and the switching module to conduct. Then, the TVS test board acquires the first measured voltage of the first ADC pin and the second measured voltage of the second ADC pin, as well as the voltage divider current of the voltage divider module. Based on the first and second measured voltages, it determines the first voltage V1 and the second voltage V2 across the voltage divider module. Then, based on the first voltage, the second voltage, and the voltage divider current, it determines the positive test result of the first round of testing for the i-th TVS diode.

[0113] If the test passes, in the second round of testing, let the initial voltage V10 = V10 + 5. Then the target value of the first voltage V1 = V10 + 5 = 15V. Based on the new target value, determine the output voltage V0 of the DAC pin, V0 = 15 / y0. After that, the DAC pin outputs this output voltage V0, thus starting the second round of testing for the i-th TVS diode.

[0114] If the test passes, in the third round of testing, let the initial voltage V10 = 15 + 5, then the target value of the first voltage V1 = 20V. Based on the new target value, determine the output voltage V0 of the DAC pin, V0 = 20 / y0. Then, the DAC pin outputs this output voltage V0, thus starting the third round of testing for the i-th TVS diode... until the testing of the i-th TVS diode is completed.

[0115] The difference between negative and positive testing procedures is that during negative testing, the module is switched to negative mode; otherwise, they are the same. The negative testing procedure will not be elaborated further here.

[0116] Using this approach, the TVS test board automatically performs multiple rounds of testing on the TVS diode based on the starting voltage, growth rate, and maximum voltage in the test parameters, thereby improving the testing efficiency of the TVS diode.

[0117] Optionally, in the above embodiments, when the test mode is bidirectional testing, and a forward test is performed on the i-th TVS tube, the TVS test board controls the switching module to switch to forward mode and performs a forward test on the i-th TVS tube. Please refer to... Figure 3In the forward mode, current flows from the forward test pin of the i-th TVS diode to the negative test pin of the i-th TVS diode. Moreover, the forward test of the i-th TVS diode includes multiple rounds of testing, which are specifically related to the starting voltage, the increase magnitude, and the maximum voltage, etc. For details, please refer to the aforementioned embodiments, which will not be repeated here.

[0118] After performing a positive test on the i-th TVS diode, the switching module is controlled to switch to negative mode. The TVS test board controls the switching module to switch to negative mode and performs a negative test on the i-th TVS diode. Please refer to... Figure 3 In negative mode, current flows from the negative test pin of the i-th TVS diode to the positive test pin of the i-th TVS diode. Similarly, the negative test of the i-th TVS diode also includes multiple rounds of testing.

[0119] It should be noted that, regardless of whether it's a positive or negative test, taking the positive test as an example, if any round of testing fails, it means the i-th TVS diode is defective, and testing of the i-th TVS diode is stopped, and testing of the (i+1)-th TVS diode begins. If all rounds of testing pass, it means the i-th TVS diode passes the positive test. The negative test is similar to the positive test and will not be elaborated here.

[0120] Additionally, it should be noted that the embodiments of this application do not limit the order of positive and negative testing. The testing order can be positive testing first and then negative testing, or negative testing first and then positive testing. When the testing order is positive testing first and then negative testing, if a round of positive testing fails, there is no need to perform negative testing on the i-th TVS diode; instead, testing begins on the (i+1)-th TVS diode.

[0121] Similarly, if the test order is negative test first and then positive test, if a negative test fails in a certain round, there is no need to perform a positive test on the i-th TVS tube, but instead start testing the (i+1)-th TVS tube.

[0122] Using this scheme, for the i-th TVS diode, the TVS test board automatically performs positive and negative tests without the need to manually change the contacts; moreover, after testing the i-th TVS diode, it automatically tests the (i+1)-th TVS diode, thereby improving the testing efficiency of TVS diodes.

[0123] Optionally, in the above embodiments, when the test mode is a unidirectional test, the TVS test board determines whether the unidirectional test is a positive test or a negative test based on the test parameters. When the unidirectional test is a positive test, the TVS test board controls the switching module 16 to switch to positive mode and performs a positive test on the i-th TVS diode. When the unidirectional test is a negative test, the TVS test board controls the switching module 16 to switch to negative mode and performs a negative test on the i-th TVS diode. In the positive mode, current flows from the positive test pin of the i-th TVS diode to the negative test pin of the i-th TVS diode, and in the negative mode, current flows from the negative test pin of the i-th TVS diode to the negative test pin of the i-th TVS diode.

[0124] For example, all TVS diodes at at least one interface of the product under test form a TVS queue, which contains TVS diodes of various specifications. Two TVS diodes of different specifications refer to differences in one or more parameters such as test mode, clamping voltage range, maximum current, starting voltage, increment amplitude, and maximum voltage. For instance, one TVS diode is a unidirectional TVS diode, and the other is a bidirectional TVS diode, with test modes of unidirectional and bidirectional testing, respectively. When a TVS diode is in unidirectional test mode, the TVS test board obtains the test parameters of that TVS diode through serial communication, determines whether the unidirectional test is a positive or negative test based on the test parameters, and then performs the test on the TVS diode.

[0125] With this approach, for the i-th TVS diode, when the TVS diode is unidirectional, the TVS test board determines whether the unidirectional test is a positive or negative test based on the test parameters and performs the test automatically; moreover, after testing the i-th TVS diode, it automatically tests the (i+1)-th TVS diode, thereby improving the efficiency of TVS diode testing.

[0126] The following example illustrates the test method described in this application. In this embodiment, the total number of TVS diodes in at least one interface of the product under test is three, namely TVS diode 1, TVS diode 2, and TVS diode 3. TVS diode 1 is a bidirectional diode with a clamping voltage V4 of 15.60-17.20V and a maximum current of 5mA. TVS diode 2 is a unidirectional diode with a clamping voltage V4 of 20.00-22.1V and a maximum current of 4mA. TVS diode 3 is a bidirectional diode with a clamping voltage V4 of 31.10-34.4V and a maximum current of 1mA. In the TVS test board, the control module 11 is a microcontroller, the ADC uses two sampling channels with a sampling accuracy of 12 bits, an AD data range of 0-4095, an input range of 0-3.3V, and uses DMA for continuous sampling. The DAC uses 12-bit digital data conversion, with a data range of 0-4095 and an output range of 0-3.3V. It uses DMA for continuous output. The testing process can be found in [link to test procedure]. Figure 5 .

[0127] Figure 5 This is another flowchart of the testing method provided in this application embodiment. This embodiment includes:

[0128] 501. TVS test board initialization.

[0129] For example, the TVS test board is initialized with the initial total number P of TVS diodes to be tested and the TVS queue. Since the total number of TVS diodes in at least one interface of the product under test is 3, the total number P = 3, and the TVS queue consists of TVS diode 1, TVS diode 2, and TVS diode 3. Simultaneously, the TVS test board sets i = 1.

[0130] 502. Determine whether the i-th TVS tube needs to be tested. If the i-th TVS tube needs to be tested, proceed to step 503; if the i-th TVS tube does not need to be tested, proceed to step 512.

[0131] 503. Obtain the test parameters of the i-th TVS tube.

[0132] In this embodiment, the test parameters include the test mode, voltage drop of the voltage divider module, clamping voltage range, maximum current, starting voltage, growth amplitude, and maximum voltage. For details, please refer to the above description of the test parameters for the i-th TVS diode; they will not be repeated here.

[0133] 504. Determine whether a forward test is needed for the i-th TVS diode. If a forward test is needed for the i-th TVS diode, proceed to step 505; if a forward test is not needed for the i-th TVS diode, proceed to step 508.

[0134] 505. Switch the control switching module to positive mode.

[0135] In this embodiment, in the forward mode, the current flows from the positive test pin of the i-th TVS transistor to the negative test pin of the i-th TVS transistor. Please refer to... Figure 3 The TVS test board controls the intermediate relay K0 to close, thus entering the positive mode.

[0136] 506. Perform a forward test on the i-th TVS transistor.

[0137] 507. Determine whether the i-th TVS diode passes the forward test. If the i-th TVS diode passes the forward test, proceed to step 508; if the i-th TVS diode fails the forward test, proceed to step 511.

[0138] 508. Determine whether a negative test is needed for the i-th TVS diode. If a negative test is needed for the i-th TVS diode, proceed to step 509; if a negative test is not needed for the i-th TVS diode, proceed to step 511.

[0139] 509. Switch the control switching module to negative mode.

[0140] In this embodiment, in negative mode, current flows from the negative test pin of the i-th TVS diode to the positive test pin of the i-th TVS diode. Please refer to... Figure 3 The TVS test board controls the intermediate relay K0 to disconnect, thus entering the negative mode.

[0141] 510. Perform a negative test on the i-th TVS transistor.

[0142] The TVS test board performs a negative test on the i-th TVS diode and determines whether the i-th TVS diode passes the negative test. If the i-th TVS diode passes the negative test, the test result in step 511 indicates that the i-th TVS diode has passed the negative test; otherwise, the test result in step 511 indicates that the i-th TVS diode has failed the negative test.

[0143] 511. Output the test result of the i-th TVS tube.

[0144] If the TVS test board performs both a positive and a negative test on the i-th TVS diode, it outputs the positive and negative test results, respectively. If the TVS test board performs a positive test on the i-th TVS diode, it outputs the positive test result. If the TVS test board performs a negative test on the i-th TVS diode, it outputs the negative test result.

[0145] The TVS test board can output test results through serial port printing, digital tube display, or communication with a host computer. This application embodiment does not limit the output method of the test results.

[0146] 512. Let i=i+1.

[0147] 513. Determine whether the test is complete. If the test is complete, end the process. If the test is not complete, proceed to step 502.

[0148] For example, the TVS test board determines whether the new i is greater than or equal to the total number P in step 501. When i > P, the TVS test board determines that the test is complete; when i ≤ P, it continues to test the next TVS tube.

[0149] The above Figure 5 In the embodiment, steps 506 and 510 represent positive and negative tests, respectively. The difference between positive and negative tests lies in the operating mode of the switching module. During a positive test, the switching module operates in positive mode; during a negative test, the switching module operates in negative mode. Please refer to... Figure 3 When contacts 3 and 4, and contacts 5 and 6 of intermediate relay K0 are closed, switching module 16 is in positive mode. In this mode, current flows from the positive test pin to the negative test pin of the TVS diode, thus achieving a positive test of the TVS diode. When switching module 16 is connected to the TVS diode, and contacts 3 and 5, and contacts 6 and 7 of intermediate relay K0 of switching module 16 are closed, switching module 16 is in negative mode. In this mode, current flows from the negative test pin to the positive test pin of the TVS diode, thus achieving a negative test of the TVS diode.

[0150] Aside from the different operating modes of the switching modules, the positive and negative tests are similar in all other aspects. Below, we describe in detail one round of positive testing for the i-th TVS diode; the negative test procedure can be referred to the positive test procedure.

[0151] Figure 6 This is another flowchart of the testing method provided in the embodiments of this application. This embodiment includes:

[0152] 601. Determine the target value of the voltage amplification module based on the starting voltage.

[0153] For example, the TVS test board uses the initial voltage V10 as the target value of the first voltage V1. For instance, if V10 = 5V, then the target value of the first voltage V1 is 5V.

[0154] 602. Control the on / off unit of the i-th TVS tube to conduct, so that the i-th TVS tube and the switching module are connected.

[0155] Please refer to Figure 3 Taking the i-th TVS tube as TVS tube 1 as an example, the TVS test board controls the intermediate relay K1 to conduct through GPIO_1, thereby enabling the i-th TVS tube and the switching module to conduct.

[0156] 603. The TVS test board determines the output voltage V0 of the DAC pin based on the target value and controls the DAC pin to output the output voltage V0.

[0157] Please refer to Figure 3 The amplification factor of the voltage amplification module is y0. Therefore, the output voltage V0 = target value / y0. Continuing with the example in step 601, assuming y0 = 20, then V0 = 5 / 20 = 0.25V. After the output voltage V0 is amplified by the voltage amplification module 12, the first voltage V1 is generated.

[0158] It is understandable that, due to losses and other factors, the first voltage V1 may not be equal to the target value.

[0159] 604. The TVS test board acquires the first measured voltage of the first ADC pin and the second measured voltage of the second ADC pin, and determines the voltage divider current of the voltage divider module.

[0160] 605. The TVS test board determines the first voltage V1 and the second voltage V2 across the voltage divider module based on the first measured voltage and the second measured voltage.

[0161] Please refer to Figure 3 The scaling factor of the first scaling module 13 is y1, and the first measured voltage is represented by V20. Then V1 = V20 × y1. When y1 = 34, V1 = V20 × 34.

[0162] Similarly, the scaling factor of the second scaling module 14 is y2, and the second measured voltage is represented by V21, then V2 = V21 × y2. When y2 = 34, V2 = V21 × 34.

[0163] Let I2 represent the voltage divider current, then I2 = (V1 - V2) / R11 × 1000. Taking the resistance of R11 as 62000 ohms as an example, I2 = (V1 - V2) / 62000 × 1000. The reason for multiplying by 1000 is that the current is measured in milliamperes.

[0164] 606. The TVS test board determines whether the first round of testing of the i-th TVS tube passes the first round of testing. If the first round of testing of the i-th TVS tube passes the first round of testing, then proceed to step 607; if the first round of testing of the i-th TVS tube fails the first round of testing, then proceed to step 609.

[0165] The TVS test board determines the forward test result of the first round of testing for the i-th TVS diode based on the first voltage, the second voltage, and the voltage divider current. If the forward test result indicates that the i-th TVS diode has passed the forward test, then step 607 is executed; if the forward test result indicates that the i-th TVS diode has failed the forward test, then step 609 is executed.

[0166] The TVS test board compares the first voltage V1 with the maximum value of the clamping voltage range of the i-th TVS diode. When the first voltage V1 is less than the maximum value of the clamping voltage range, it indicates that the i-th TVS diode is in a non-operating state. When the first voltage V1 is greater than or equal to the maximum value of the clamping voltage range, it indicates that the i-th TVS diode is in an operating state.

[0167] When the i-th TVS diode is in a non-operating state, the TVS test board compares the relationship between the difference between the first voltage V1 and the second voltage V2 and the voltage drop of the voltage divider module, as well as the relationship between the voltage divider current and the maximum current. When the difference between the first voltage V1 and the second voltage V2 is less than the voltage drop V3 of the voltage divider module, and the voltage divider current I2 is less than the maximum current Imax, the TVS test board determines that the TVS diode has passed the first round of forward testing. That is, the forward test result of the first round of testing indicates that the TVS diode has passed the forward test.

[0168] When the difference between the first voltage V1 and the second voltage V2 is greater than or equal to the voltage drop V3 of the voltage divider module, and / or the voltage divider current I2 is greater than or equal to the maximum current Imax, the TVS test board determines that the positive test result of the first round of testing indicates that the TVS tube has failed the positive test.

[0169] Using this approach, when the TVS diode is not in operation, the TVS test board determines whether the TVS diode has passed the current round of forward testing by comparing the difference between the first voltage and the second voltage with the voltage drop of the voltage divider module, as well as the relationship between the voltage divider current and the maximum current. This method is fast and accurate.

[0170] Optionally, when the i-th TVS diode is in operation, the TVS test board compares the relationship between the second voltage V2 and the clamping voltage range, as well as the relationship between the voltage divider current and the maximum current Imax. When the second voltage V2 falls within the clamping voltage range and the voltage divider current is less than the maximum current Imax, the forward test result indicates that the TVS diode has passed the forward test; when the second voltage V2 does not fall within the clamping voltage range, and / or the voltage divider current is greater than or equal to the maximum current Imax, the forward test result of the first round of testing indicates that the TVS diode has failed the forward test.

[0171] Using this approach, when the TVS diode is in operation, the TVS test board determines whether the TVS diode has passed the current round of forward testing based on the relationship between the second voltage V2 and the clamping voltage range, as well as the relationship between the voltage divider current and the maximum current Imax. This method is fast and highly accurate.

[0172] 607. Increase the starting voltage according to the growth rate.

[0173] When the positive test result of the xth test indicates that the TVS diode has passed the positive test, the TVS test board increases the starting voltage according to the increase magnitude to attempt to start the (x+1)th test, where x ≥ 1 and is an integer.

[0174] For example, in the first round of testing, the target value of the first voltage V1 is equal to the starting voltage V0. After the TVS diode passes the first round of testing, the starting voltage V10 is set to V10 + 5, and the target value of the first voltage V1 is V10 = 15V. After the TVS diode passes the second round of testing, the starting voltage V10 is set to 15 + 5, and the target value of the first voltage V1 is V10 = 20V...

[0175] 608. The TVS test board determines whether the increased starting voltage is less than or equal to the maximum voltage. If the increased starting voltage is less than or equal to the maximum voltage, return to step 601; if the increased starting voltage is greater than the maximum voltage, proceed to step 609.

[0176] Each time the starting voltage is increased, the TVS test board determines that the forward test of the i-th TVS tube is completed when the increased starting voltage is greater than the maximum voltage.

[0177] 609. Disconnect the intermediate relay in the on / off unit corresponding to the i-th TVS test tube.

[0178] 610. Output the test results.

[0179] Using this approach, after each round of testing, the TVS test board automatically adjusts the target value of the first voltage and adjusts the output voltage of the DAC pin according to the target value, so as to automatically complete multiple rounds of testing on the TVS tube and improve the testing efficiency of the TVS tube.

[0180] This application also provides a computer-readable storage medium storing computer instructions, which, when executed by a control module on a TVS test board, are used to implement the test method described above.

[0181] This application also provides a computer program product, which includes a computer program that, when executed by a control module on a TVS test board, implements the instance segmentation method described above.

[0182] In this embodiment of the application, the control module on the TVS test board can be implemented using at least one of the following hardware forms: Digital Signal Processing (DSP), Field-Programmable Gate Array (FPGA), and Programmable Logic Array (PLA).

[0183] Those skilled in the art will understand that embodiments of this application provide methods, systems, or computer program products. Therefore, this application may take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0184] The above are merely embodiments of this application and are not intended to limit the scope of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of the claims of this application.

Claims

1. A TVS test board, characterized by, include: The system includes a control module, a voltage amplification module, a first scaling module, a second scaling module, a voltage divider module, a switching module, and M on / off units. Different on / off units among the M on / off units are used to connect different TVS diodes of the interface of the product under test. The product under test has at least one interface, and the total number of TVS diodes of at least one interface of the product under test is ≤M, where M≥1. The on / off units are used to control the connection and disconnection between the TVS diodes and the switching module. At any given time, one on / off unit among the M on / off units is on, while the remaining on / off units are off. The switching module is used to control whether the TVS diodes are tested in the positive or negative direction. The control module has at least a DAC pin, a first ADC pin, a second ADC pin, and N+1 input / output pins. The DAC pin is connected to the input terminal of the voltage amplification module, the first ADC pin is connected to the first terminal of the first scaling module, the second ADC pin is connected to the first terminal of the second scaling module, one of the N+1 input / output pins is connected to the switching module, and M of the remaining N input / output pins are respectively connected to different switching units in the M switching units, where M≤N; The output terminal of the voltage amplification module is connected to the second terminal of the first scaling module and the first terminal of the voltage divider module. The second end of the voltage divider module is connected to the second end of the second scaling module and the switching module.

2. The TVS test board according to claim 1, characterized in that, When the number of at least one product under test interface is ≥2, at least two product under test interfaces contain two or more types of product under test interfaces, and the number of TVS tubes contained in different types of product under test interfaces is different.

3. A test method characterized by, Applied to the TVS test board as described in claim 1 or 2, the method includes: Determine the total number of TVS transistors and the TVS queue in at least one interface of the product under test, wherein the TVS queue is obtained by sorting the TVS transistors in the at least one interface of the product under test. According to the order indicated by the TVS queue, each TVS tube in the TVS queue is tested sequentially; After each TVS tube in the TVS queue is tested, the total number and the number of TVS tubes tested are used to determine whether the testing of all TVS tubes in the TVS queue is complete. If the testing of each TVS tube in the TVS queue is not completed, continue testing the TVS tubes in the TVS queue until the testing of each TVS tube in the TVS queue is completed.

4. The method of claim 3, wherein, The step of testing each TVS tube in the TVS queue sequentially according to the order indicated by the TVS queue includes: When it is the i-th TVS tube in the TVS queue, the test parameters of the i-th TVS tube are obtained. The test parameters are used to indicate the test mode. The test mode includes any one of the following: shutdown test, bidirectional test, and unidirectional test. The bidirectional test includes positive test and negative test. When the test mode is bidirectional test or unidirectional test, the test parameters are also used to indicate the voltage drop of the voltage divider module, the clamping voltage range and maximum current of the TVS tube, the starting voltage of the output terminal of the voltage amplification module, the growth magnitude of the starting voltage, and the maximum voltage of the output terminal of the voltage amplification module, where 1≤i≤total number and are integers. Test the i-th TVS tube according to the test parameters of the i-th TVS tube.

5. The method of claim 4, wherein, The step of testing the i-th TVS diode according to the test parameters of the i-th TVS diode includes: When the test mode is bidirectional test and a positive test is performed on the i-th TVS transistor, the switching module is controlled to switch to positive mode. In the positive mode, the current flows from the positive test pin of the i-th TVS transistor to the negative test pin of the i-th TVS transistor. Perform a forward test on the i-th TVS diode; After performing a positive test on the i-th TVS transistor, the switching module is controlled to switch to a negative mode. In the negative mode, the current flows from the negative test pin of the i-th TVS transistor to the positive test pin of the i-th TVS transistor. Perform a negative test on the i-th TVS transistor.

6. The method of claim 4, wherein, The step of testing the i-th TVS diode according to the test parameters of the i-th TVS diode includes: When the test mode is a one-way test, the one-way test is determined to be a positive test or a negative test according to the test parameters; When the unidirectional test is a positive test, the switching module is controlled to switch to positive mode and a positive test is performed on the i-th TVS tube; When the unidirectional test is a negative test, the switching module is controlled to switch to negative mode and a negative test is performed on the i-th TVS tube; In the positive mode, the current flows from the positive test pin of the i-th TVS transistor to the negative test pin of the i-th TVS transistor, and in the negative mode, the current flows from the negative test pin of the i-th TVS transistor to the negative test pin of the i-th TVS transistor.

7. The method according to claim 5 or 6, characterized in that, The forward test performed on the i-th TVS diode includes: The target value of the voltage amplification module is determined based on the starting voltage; Based on the target value, determine the output voltage of the DAC pin, and control the DAC pin to output the output voltage so that the TVS test board starts the first round of testing; Control the on / off unit of the i-th TVS tube to conduct, so that the i-th TVS tube and the switching module are connected; The first measured voltage of the first ADC pin and the second measured voltage of the second ADC pin, as well as the voltage divider current of the voltage divider module, are collected. The first voltage and the second voltage across the voltage divider module are determined based on the first measured voltage and the second measured voltage. Based on the first voltage, the second voltage, and the voltage divider current, the forward test result of the first round of testing of the i-th TVS diode is determined. The forward test includes multiple rounds of testing, and the number of rounds of testing is determined based on the starting voltage, the growth amplitude, and the maximum voltage.

8. The method of claim 7, wherein, The step of determining the positive test result of the first round of testing of the i-th TVS diode based on the first voltage, the second voltage, and the voltage divider current includes: The TVS diode is determined to be in a non-operating state or an operating state. In the non-operating state, the first voltage is less than the maximum value of the clamping voltage range. In the operating state, the first voltage is greater than or equal to the maximum value of the clamping voltage range. When the TVS diode is in a non-operating state, if the difference between the first voltage and the second voltage is less than the voltage drop of the voltage divider module and the voltage divider current is less than the maximum current, the positive test result of the first round of testing indicates that the TVS diode has passed the positive test. When the TVS diode is in a non-operating state, if the difference between the first voltage and the second voltage is greater than or equal to the voltage drop of the voltage divider module, and / or the voltage divider current is greater than or equal to the maximum current, the positive test result of the first round of testing indicates that the TVS diode has failed the positive test.

9. The method of claim 8, wherein, Also includes: When the TVS diode is in operation, if the second voltage falls within the clamping voltage range and the voltage divider current is less than the maximum current, the positive test result indicates that the TVS diode has passed the positive test. When the TVS diode is in operation, if the second voltage does not fall within the clamping voltage range, and / or the voltage divider current is greater than or equal to the maximum current, the positive test result of the first round of testing indicates that the TVS diode has failed the positive test.

10. The method according to claim 8 or 9, characterized in that, Also includes: When the positive test result of the first round of testing indicates that the TVS tube has passed the positive test, the starting voltage is increased according to the increase amplitude to start the second round of testing; Each time the starting voltage is increased, if the increased starting voltage is greater than the maximum voltage, it is determined that the forward test of the i-th TVS diode is completed.

11. A computer readable storage medium having stored thereon a computer program, characterized in that, When the computer program is executed by a processor, it implements the method as described in any one of claims 3 to 10.

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