Method and device for testing fatigue characteristics of bidirectional conduction device

Abstract

The application discloses a kind of bidirectional conducting device fatigue characteristic test method and device, belong to semiconductor technical field, wherein, one end of the bidirectional conducting device to be measured is connected with pulse generator, the other end is connected with capacitor;Test method includes: S1, sends continuous pulse signal to the bidirectional conducting device to be measured by pulse generator;Wherein, the amplitude of pulse signal is greater than the threshold voltage of bidirectional conducting device, and pulse width is greater than the opening time of bidirectional conducting device;S2, the voltage V C When voltage V C When the condition is not satisfied, the opening number of the bidirectional conducting device is obtained based on the number of pulse signals emitted by the current pulse generator;The application detects the fatigue characteristic parameters of the bidirectional conducting device based on the capacitor voltage, and the charging time of the capacitor can ensure the normal opening of the bidirectional conducting device to be measured, avoiding the rapid shutdown phenomenon after the voltage drop caused by the resistance change of the bidirectional conducting device, which is more accurate and the test circuit is relatively simple.

Description

Technical Field

[0001] This invention belongs to the field of semiconductor technology, and more specifically, relates to a method and apparatus for testing the fatigue characteristics of bidirectional conductive devices. Background Technology

[0002] With the rapid development of information network technology, information is exploding, creating new demands in fields such as memory and communication systems. Bidirectional conductive devices are widely used due to their versatility and superior integration. For example, bidirectional diodes play a crucial role in sensitive circuits, protecting devices by limiting voltage. Furthermore, selector transistors also hold an irreplaceable position in the memory field. In practical applications, the number of switching cycles of a bidirectional conductive device determines its lifespan; therefore, the fatigue characteristics (i.e., the number of switching cycles) of a bidirectional conductive device determine its practical application. Based on this, researching a testing method and apparatus for the fatigue characteristics of bidirectional conductive devices and conducting accurate fatigue characteristic tests is of great significance.

[0003] In existing technical solutions, the commonly used fatigue testing method for bidirectional conducting devices involves connecting a series resistor, using a pulse generator to output pulses to operate the bidirectional conducting device, and then reading the device's on-state current or off-state resistance to determine if the device has failed. This method requires a relatively complex reading circuit for device status detection. Furthermore, only a small series resistor can be used, limiting current-limiting capability; otherwise, voltage division can cause device oscillation, which is detrimental to fatigue characteristic testing. Also, since bidirectional conducting devices often operate under high-frequency signals and have short on-time, real-time monitoring is inconvenient. Monitoring is typically done by applying a certain number of pulses and then checking the device's status, which is not suitable for real-time detection. In addition, if monitoring the on-state current is used to determine if a bidirectional conducting device has failed, a wider pulse is needed to accurately observe its operating state, which affects the device's fatigue characteristics, resulting in lower accuracy. Similarly, if monitoring the off-state resistance of the bidirectional conducting device is used to determine failure, the accuracy is also low because there are cases where the bidirectional conducting device is not turned on when the off-state resistance is normal. Summary of the Invention

[0004] In view of the above-mentioned defects or improvement needs of the prior art, the present invention provides a fatigue characteristic testing device and method for bidirectional conductive devices, which solves the technical problem that the prior art cannot accurately detect the fatigue characteristics of bidirectional conductive devices with a relatively simple testing circuit.

[0005] To achieve the above objectives, in a first aspect, the present invention provides a method for testing the fatigue characteristics of a bidirectional conductive device, wherein one end of the bidirectional conductive device under test is connected to a pulse generator, and the other end is connected to a capacitor; the other end of the capacitor is grounded.

[0006] The fatigue characteristic test method for bidirectional conductive devices includes the following steps:

[0007] S1. A continuous pulse signal is sent to the bidirectional conducting device under test through a pulse generator; wherein the amplitude of the pulse signal is greater than the threshold voltage of the bidirectional conducting device under test, and the pulse width is greater than the turn-on time of the bidirectional conducting device under test.

[0008] S2. Detect the voltage V across the capacitor. C When the voltage V C Not satisfied Under certain conditions, based on the number of pulse signals emitted by the current pulse generator, the number of times the bidirectional conducting device under test is turned on is obtained;

[0009] Where V0 is the amplitude of the pulse signal; R OFF X represents the off-state resistance of the bidirectional conductive device under test; C is the capacitance impedance of the capacitor.

[0010] More preferably, the capacitance C of the capacitor is selected based on the magnitude I of the current when the bidirectional conducting device under test is actually working and the signal output frequency f of the pulse generator;

[0011] The capacitance C, the current I, and the signal output frequency f satisfy the following relationship:

[0012]

[0013]

[0014] Among them, R ON The on-state resistance of the bidirectional conductive device under test is given.

[0015] More preferably, when When V is reached, it is determined that the bidirectional conductive device under test has not yet failed; when V C When V = 0, the bidirectional conducting device under test is determined to have low resistance failure; when When the high resistance of the bidirectional conductive device under test is detected, it is determined that the device has failed.

[0016] More preferably, the pulse signal is a positive or negative pulse signal; in this case, the number of times the bidirectional conduction device is turned on is the number of pulse signals emitted by the current pulse generator.

[0017] More preferably, the pulse signal is a unidirectional pulse signal; in this case, the number of times the bidirectional conduction device is turned on is twice the number of pulse signals emitted by the current pulse generator.

[0018] More preferably, the pulse width of the pulse signal is 2 to 3 times the turn-on time of the bidirectional conducting device under test.

[0019] Secondly, the present invention provides a fatigue characteristic testing device for bidirectional conductive devices, comprising:

[0020] A pulse generator is connected to one end of the bidirectional conductive device under test and is used to send continuous pulse signals to the bidirectional conductive device under test.

[0021] A capacitor, one end of which is connected to the other end of the bidirectional conductive device under test, and the other end is grounded;

[0022] The test module is used to detect the voltage V across the capacitor. C When the voltage V C Not satisfied Under certain conditions, based on the number of pulse signals emitted by the current pulse generator, the number of times the bidirectional conduction device is turned on is obtained;

[0023] Wherein, the amplitude of the pulse signal is greater than the threshold voltage of the bidirectional conducting device under test, and the pulse width is greater than the turn-on time of the bidirectional conducting device under test; V0 is the amplitude of the pulse signal; R OFF X represents the off-state resistance of the bidirectional conductive device under test; C is the capacitance impedance of the capacitor.

[0024] More preferably, the capacitance C of the capacitor is selected based on the magnitude I of the current when the bidirectional conducting device under test is actually working and the signal output frequency f of the pulse generator;

[0025] The capacitance C, the current I, and the signal output frequency f satisfy the following relationship:

[0026]

[0027]

[0028] Among them, R ON The on-state resistance of the bidirectional conductive device under test is given.

[0029] In summary, the above-described technical solutions conceived in this invention can achieve the following beneficial effects:

[0030] 1. This invention provides a method and apparatus for testing the fatigue characteristics of a bidirectional conductive device. The bidirectional conductive device under test is connected in series with a capacitor, and a continuous pulse signal is sent to the device via a pulse generator. This invention uses the capacitor voltage as the basis for detecting the fatigue characteristic parameters of the bidirectional conductive device. The charging time of the capacitor ensures that the bidirectional conductive device under test can turn on normally, avoiding the uncertainty of the number of turns caused by oscillations due to voltage division changes caused by changes in the resistance of the bidirectional conductive device. It also reduces the difficulty of monitoring the working state of bidirectional conductive devices in existing technologies. Therefore, it enables more accurate detection, and the test circuit is relatively simple.

[0031] 2. In the fatigue characteristic testing method and apparatus for bidirectional conductive devices provided by the present invention, the capacitance of the capacitor is selected according to the actual current magnitude of the bidirectional conductive device under test and the signal output frequency of the pulse generator, so as to select a capacitor of appropriate size, thereby more accurately controlling the current magnitude in the circuit, making it closer to the actual current during operation, and thus achieving more accurate detection.

[0032] 3. The fatigue characteristic testing method and apparatus for bidirectional conducting devices provided by the present invention sends continuous alternating positive and negative pulses to the bidirectional conducting device under test through a pulse generator, thereby increasing the voltage difference across the bidirectional conducting device by utilizing the voltage retained on the capacitor. This can effectively solve the technical problem that the bidirectional conducting device cannot be turned on due to the drift of the threshold voltage and holding voltage of the bidirectional conducting device under test.

[0033] 4. The fatigue characteristic testing method and apparatus for bidirectional conducting devices provided by the present invention retains the response of the capacitor to the previous pulse. Even under narrow pulse signals, the capacitor can still retain the response to the pulse. Therefore, it can monitor the working status of the bidirectional conducting device under test in real time and realize the real-time testing of the fatigue characteristics of the bidirectional conducting device. Attached Figure Description

[0034] Figure 1 A flowchart of the fatigue characteristic testing method for bidirectional conductive devices provided by the present invention;

[0035] Figure 2 This is a schematic diagram of a fatigue characteristic testing device for bidirectional conduction devices provided in an embodiment of the present invention;

[0036] Figure 3 This is a schematic diagram of the method for calculating the turn-on time of the selector provided in an embodiment of the present invention;

[0037] Figure 4 This is a schematic diagram of the apparatus for testing the fatigue characteristics of a selector tube provided in an embodiment of the present invention;

[0038] Figure 5 The current-time relationship diagram of the selector tube using a series large resistor current limiting scheme provided in an embodiment of the present invention;

[0039] Figure 6 This is a schematic diagram of the current-time relationship of the bidirectional selector before the selector fails when the pulse generator 101 outputs a unidirectional pulse signal, provided in an embodiment of the present invention.

[0040] Figure 7 This is a schematic diagram illustrating the voltage-time relationship between the output pulse and the capacitor before the selector fails when the pulse generator 101 outputs a unidirectional pulse signal, as provided in an embodiment of the present invention.

[0041] Figure 8 This is a schematic diagram illustrating the voltage-time relationship between the output pulse and the capacitor after the low resistance of the selector fails when the pulse generator 101 outputs a unidirectional pulse signal, as provided in an embodiment of the present invention.

[0042] Figure 9 This is a schematic diagram of the voltage-time relationship between the output pulse and the capacitor after the high impedance of the selector fails when the pulse generator 101 outputs a unidirectional pulse signal, provided in an embodiment of the present invention.

[0043] Figure 10 This is a schematic diagram of the current-time relationship of the bidirectional selector before it fails when the pulse generator 101 outputs a positive or negative pulse signal, provided in an embodiment of the present invention.

[0044] Figure 11 This is a schematic diagram illustrating the voltage-time relationship between the output pulse and the capacitor before the selector fails, provided by an embodiment of the present invention, when the pulse generator 101 outputs a positive or negative pulse signal.

[0045] Figure 12 This is a schematic diagram illustrating the voltage-time relationship between the output pulse and the capacitor after the low resistance of the selector fails when the pulse generator 101 outputs a positive or negative pulse signal, as provided in an embodiment of the present invention.

[0046] Figure 13 This is a schematic diagram illustrating the voltage-time relationship between the output pulse and the capacitor after the high impedance of the selector fails when the pulse generator 101 outputs a positive or negative pulse signal, as provided in an embodiment of the present invention. Detailed Implementation

[0047] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0048] To achieve the above objectives, in a first aspect, the present invention provides a method for testing the fatigue characteristics of a bidirectional conductive device, wherein one end of the bidirectional conductive device under test is connected to a pulse generator, and the other end is connected to a capacitor; the other end of the capacitor is grounded.

[0049] like Figure 1 As shown, the fatigue characteristic test method for bidirectional conductive devices includes the following steps:

[0050] S1. A continuous pulse signal is sent to the bidirectional conducting device under test via a pulse generator; wherein the amplitude of the pulse signal is greater than the threshold voltage of the bidirectional conducting device under test, and the pulse width is greater than the turn-on time of the bidirectional conducting device under test; preferably, the pulse width of the pulse signal is 2 to 3 times the turn-on time of the bidirectional conducting device under test.

[0051] S2. Detect the voltage V across the capacitor. C When the voltage V C Not satisfied Under certain conditions, the bidirectional conducting device under test is in a failed state. At this time, based on the number of pulse signals emitted by the current pulse generator, the number of times the bidirectional conducting device under test is turned on is obtained; where V0 is the amplitude of the pulse signal; R OFF X represents the off-state resistance of the bidirectional conductive device under test; C is the capacitance impedance of the capacitor.

[0052] It should be noted that in this invention, the capacitor is connected in series with the device. When the bidirectional conducting device under test fails due to high resistance, the bidirectional conducting device under test is in the off state, and the resistance is R. OFF The capacitance impedance is X C The total resistance of the circuit is R. OFF +X C According to the series voltage divider principle, the voltage drop across the capacitor is now... When the low-resistance component fails, it conducts. Compared to the capacitor's impedance, its resistance is negligible, and the capacitor voltage is the output voltage V0. However, when the capacitor voltage divider is in... Between V0 and V0, the bidirectional conductive device under test has not yet failed. Therefore, this invention can not only test and obtain the fatigue characteristic parameters of the bidirectional conductive device (the number of times the bidirectional conductive device is turned on), but also the failure type of the bidirectional conductive device. Specifically, when... When V is reached, it is determined that the bidirectional conductive device under test has not yet failed; when V C When V = 0, the bidirectional conducting device under test is determined to have low resistance failure; when When the high resistance of the bidirectional conductive device under test is detected, it is determined that the device has failed.

[0053] It should be noted that the aforementioned pulse signal can be a unidirectional pulse signal or a positive and negative pulse signal. When the pulse signal is a unidirectional pulse signal, the number of switching times of the bidirectional conducting device is twice the number of pulse signals emitted by the current pulse generator. When the pulse signal is a positive and negative pulse signal, the number of switching times of the bidirectional conducting device is the number of pulse signals emitted by the current pulse generator. Since alternating positive and negative pulses can effectively solve the problem of the bidirectional conducting device failing to open due to the drift of the threshold voltage and holding voltage of the bidirectional conducting device under test, positive and negative pulse signals are preferred in this embodiment.

[0054] Furthermore, since the operating current of bidirectional conducting devices varies greatly under different application scenarios, testing the fatigue characteristics of bidirectional conducting devices under conventional on-state current cannot reflect the true fatigue characteristics under that application scenario. To solve the above problem, in this invention, a capacitor 103 of appropriate capacitance can be selected to adjust the circuit current, making the on-state current of the bidirectional conducting device closer to the actual operating current. Preferably, the capacitance C of the capacitor is selected according to the actual operating current I of the bidirectional conducting device under test and the signal output frequency f of the pulse generator;

[0055] The capacitance C, the current I, and the signal output frequency f satisfy the following relationship:

[0056]

[0057]

[0058] Among them, R ON The on-state resistance of the bidirectional conductive device under test is given.

[0059] By selecting a capacitor of appropriate size based on the above method, the current in the circuit can be controlled more accurately, making it closer to the actual current during operation, thereby achieving more accurate detection.

[0060] Secondly, the present invention provides a fatigue characteristic testing device for bidirectional conductive devices, such as... Figure 2 As shown, it includes:

[0061] A pulse generator is connected to one end of the bidirectional conductive device under test and is used to send continuous pulse signals to the bidirectional conductive device under test.

[0062] A capacitor, one end of which is connected to the other end of the bidirectional conductive device under test, and the other end is grounded;

[0063] The test module is used to detect the voltage V across the capacitor. C When the voltage V C Not satisfied Under certain conditions, based on the number of pulse signals emitted by the current pulse generator, the number of switching times of the bidirectional conduction device is obtained;

[0064] Wherein, the amplitude of the pulse signal is greater than the threshold voltage of the bidirectional conducting device under test, and the pulse width is greater than the turn-on time of the bidirectional conducting device under test; V0 is the amplitude of the pulse signal; R OFF X represents the off-state resistance of the bidirectional conductive device under test; C is the capacitance impedance of the capacitor.

[0065] The related technical solutions are the same as the fatigue characteristic test method for bidirectional conductive devices provided in the first aspect of this invention, and will not be described in detail here.

[0066] It should be noted that the bidirectional conducting device in this invention can be a selector tube, a bidirectional diode, an OTS memory, etc., that have bidirectional conducting characteristics.

[0067] To further illustrate the fatigue characteristic testing method and apparatus for bidirectional conductive devices provided by the present invention, a detailed description is given using a selector tube with bidirectional conductive characteristics as an example:

[0068] In this embodiment, the turn-on time of the transistor under test (TUT) is measured using a Keysight B1530A (Semiconductor Device Parameter Analyzer). Specifically, a triangular wave is first generated using the WGFMU module, and a current sampling event is set. The voltage change of the triangular wave emitted by the instrument and the current change in the loop are observed. The time difference between the voltage drop and the current surge is the turn-on time of the TUT. Figure 3 As shown.

[0069] The apparatus for testing the fatigue characteristics of the selector tube provided in this embodiment is as follows: Figure 4 As shown, it includes: a pulse generator 101 and a capacitor 103; wherein, the capacitor 103 is connected to the selector transistor 102 under test, and plays the role of characterizing the holding voltage of the selector transistor and controlling the current; the other end of the capacitor 103 is grounded to realize the test path of the device.

[0070] In addition, the device in this embodiment also includes an oscilloscope 104; wherein, the oscilloscope 104 is connected in parallel with the pulse generator 101 and the capacitor 103 respectively, its first probe is connected to the non-grounded end of the capacitor, and its second probe is connected to the signal output end of the pulse generator, which can monitor the output pulse of the pulse generator and the voltage change across the capacitor in real time, so as to reflect whether the selector can be turned on and off normally, and can observe the change of the holding voltage of the selector.

[0071] As can be seen, the device of this application connects the gate transistor 102 under test in series with the capacitor 103, and the oscilloscope 104 in parallel with the capacitor 103. This allows the device to reasonably control the gate transistor's turn-on circuit and monitor the gate transistor's operating status in real time, thus eliminating the need for a reading circuit. Furthermore, the oscilloscope can reflect the gate transistor's operating status and holding voltage in real time, enabling better observation of the gate transistor's performance changes during the testing process.

[0072] Among them, capacitor 103 has a constant capacitance, which controls the conduction current of the selector and synchronizes the holding voltage of the selector. For example... Figure 1 As shown, the oscilloscope 104, pulse generator 101, and capacitor 103 are connected in parallel to reflect the voltage change across the selector transistor.

[0073] It should be noted that, if the existing method is used to limit the current of the selector under test using a large resistor R, when the selector under test is turned on, its on-state resistance RON A voltage drop much smaller than the series resistor R will cause the voltage across the selector to rapidly decrease to its holding voltage V. hold The following describes how to quickly turn off the selector transistor under test. Since the applied pulse width is 2-3 times the turn-on time of the selector transistor, it will turn on and off multiple times, which is detrimental to fatigue testing. Furthermore, its turn-on time is too short, making it difficult to monitor its normal operation with a standard oscilloscope. The corresponding current-time relationship diagram for the selector transistor is shown below. Figure 5 As stated above.

[0074] Under the testing apparatus and method provided by this invention:

[0075] 1) For the case where pulse generator 101 outputs a unidirectional pulse signal:

[0076] When pulse generator 101 outputs a pulse signal with an amplitude of V0, the voltage across selector transistor 102 is V. hold The voltage across capacitor 103 is V. C , where V0 and V C satisfy:

[0077] V0-V hold >V th

[0078] V C =V0-V hold

[0079] Among them, V hold To maintain the position of the gate; V th This is the threshold voltage of the selector.

[0080] Before the selector fails: When the pulse amplitude V0 output by pulse generator 101 is equal to the holding voltage V hold The difference is greater than the threshold voltage V of the selector 102. th When the selector transistor 102 is turned on, the resistance decreases and the current increases. After the selector transistor 102 is turned on, the capacitor 103 begins to charge, and the circuit current begins to decrease. The voltage across the selector transistor decreases. When the voltage across the selector transistor 102 drops to the holding voltage V... hold When the following condition is met, the selector transistor 102 is turned off, and capacitor 103 stops charging. At this time, the voltage V across capacitor 103 is... C =V0-V hold Then, when the output voltage V0' of the pulse generator 101 drops to V0 or below, the potential difference across the selector transistor 102 is V. C -V0'>V th At this point, selector 102 is turned on again. When the capacitor discharges to V... C =V hold Afterwards, the selector transistor 102 is turned off again, and the capacitor voltage is V. holdThroughout the process, for every pulse output by pulse generator 101, the selector transistor turns on and off twice. Therefore, during counting, the number of times the selector transistor switches on and off is twice the number of pulse signals emitted by the pulse generator. Specifically, the current-time relationship diagram of the bidirectional selector transistor before failure is shown below. Figure 6 As shown in the figure, the corresponding output pulse and the voltage-time relationship of the capacitor are illustrated in the diagram below. Figure 7 As shown.

[0081] After the high-resistance gate fails: Using the aforementioned gate 102 device with bidirectional conduction characteristics, when a fixed pulse is applied to the gate 102, the voltage of capacitor 103 after charging drops significantly, to less than or equal to... The corresponding output pulse and the voltage-time relationship of the capacitor are shown in the diagram below. Figure 8 As shown; where R OFF This is the off-state resistance of the selector transistor.

[0082] After the low-resistance of the selector fails: Utilizing the selector 102 with bidirectional conduction characteristics, when a fixed pulse is applied to the selector 102, the voltage obtained by capacitor 103 during charging will be equal to the pulse amplitude V0. The corresponding output pulse and the voltage-time relationship of the capacitor are shown in the diagram below. Figure 9 As shown.

[0083] 2) For the case where pulse generator 101 outputs positive and negative pulse signals:

[0084] When the pulse amplitude V0 output by pulse generator 101 is greater than the threshold voltage V of selector 102 th When the selector transistor 102 is turned on, the resistance decreases and the current increases. After the selector transistor 102 is turned on, the capacitor 103 begins to charge, and the circuit current begins to decrease. When the voltage across the selector transistor 102 drops to the holding voltage V... hold When the following condition is met, the selector transistor 102 is turned off, and capacitor 103 stops charging. At this time, the voltage V across capacitor 103 is... C =V0-V hold Then, pulse generator 101 outputs a negative pulse, at which point the potential difference across selector 102 is V. C -(-V0), because the selector transistor 102 has bidirectional conduction characteristics, when the potential difference is greater than or equal to the threshold voltage V th At this time, the selector transistor 102 turns on again, the resistance decreases, and the circuit current increases. Then, capacitor 103 begins to discharge, and when V... C When the voltage drops to 0, reverse charging begins again, and the voltage across the selector transistor 102 starts to decrease. When it drops to the holding voltage V... hold When the following occurs, the selector transistor 102 is turned off again, and capacitor 103 stops charging. At this time, the voltage V across capacitor 103 is... C For Vhold -V0. Throughout the process, the selector transistor turns on and off once for each pulse output by the pulse generator 101. Therefore, during counting, the number of times the selector transistor switches on and off is equal to the number of pulse signals emitted by the pulse generator. Specifically, the current-time relationship diagram of the bidirectional selector transistor before failure is shown in the figure below. Figure 10 As shown in the figure, the corresponding output pulse and the voltage-time relationship of the capacitor are illustrated in the diagram below. Figure 11 As shown.

[0085] After the high-resistance gate fails: Using the aforementioned gate 102 device with bidirectional conduction characteristics, when a fixed pulse is applied to the gate 102, the voltage of capacitor 103 after charging drops significantly, to less than or equal to... The corresponding output pulse and the voltage-time relationship of the capacitor are shown in the diagram below. Figure 12 As shown; where R OFF This is the off-state resistance of the selector transistor.

[0086] After the low-resistance of the selector fails: Utilizing the selector 102 with bidirectional conduction characteristics, when a fixed pulse is applied to the selector 102, the voltage obtained by capacitor 103 during charging will be equal to the pulse amplitude V0. The corresponding output pulse and the voltage-time relationship of the capacitor are shown in the diagram below. Figure 13 As shown.

[0087] It should be noted that bidirectional diode failures are categorized into open-circuit failures (high-resistance failures) and short-circuit failures (low-resistance failures). Their operating principle is that they conduct when the voltage is above the threshold voltage and turn off when the voltage is below the threshold voltage. OTSmemory utilizes the threshold voltage change of a selector transistor to store data; it is a device composed of selector transistors and also exhibits high-resistance and low-resistance failures. The test patterns for bidirectional diodes and OTSmemory are essentially the same as those for selector transistors; only the parameters need to be adjusted according to the device itself. The exact same test methods can also be used, which will not be elaborated upon here.

[0088] Based on the above analysis, it can be seen that the detection device in this invention has a simple structure. The charging time of the capacitor ensures the normal operation of the bidirectional conductive device under test, avoiding the uncertainty in the number of times the device can be turned on due to oscillations caused by voltage changes resulting from resistance variations in the bidirectional conductive device. It also reduces the difficulty of monitoring the operating status of bidirectional conductive devices in existing technologies. Therefore, this invention can accurately detect the fatigue characteristic parameters (number of times the bidirectional conductive device can be turned on) and the corresponding failure type of the bidirectional conductive device based on the capacitor voltage. Furthermore, under narrow pulse signals, the capacitor can still retain its response to the pulse, thus enabling real-time monitoring of the operating status of the bidirectional conductive device under test and realizing real-time testing of its fatigue characteristics. In addition, the voltage holding time after capacitor charging can be adjusted by the pulse interval, facilitating oscilloscope sampling and observation of its operating status.

[0089] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for testing the fatigue characteristics of a bidirectional conductive device, characterized in that, One end of the bidirectional conducting device under test is connected to a pulse generator, and the other end is connected to a capacitor; the other end of the capacitor is grounded. The fatigue characteristic testing method for the bidirectional conductive device includes the following steps: S1. A continuous pulse signal is sent to the bidirectional conducting device under test through the pulse generator; the amplitude of the pulse signal is greater than the threshold voltage of the bidirectional conducting device under test, and the pulse width is greater than the turn-on time of the bidirectional conducting device under test. S2. Detect the voltage V across the capacitor. C When the voltage V C Not satisfied Under certain conditions, based on the number of pulse signals emitted by the pulse generator, the number of times the bidirectional conducting device under test is turned on is obtained; Where V0 is the amplitude of the pulse signal; R OFF X is the off-state resistance of the bidirectional conducting device under test; C Let be the capacitive impedance of the capacitor.

2. The fatigue characteristic testing method for bidirectional conductive devices according to claim 1, characterized in that, The capacitance C of the capacitor is selected based on the magnitude I of the current when the bidirectional conducting device under test is actually working and the signal output frequency f of the pulse generator; The capacitor C, the current magnitude I, and the signal output frequency f satisfy the following relationship: Among them, R ON The on-state resistance of the bidirectional conductive device under test is given.

3. The fatigue characteristic testing method for bidirectional conductive devices according to claim 1, characterized in that, when When V is reached, it is determined that the bidirectional conducting device under test has not yet failed; C When V = V0, the bidirectional conducting device under test is determined to have low resistance failure; when When the high resistance of the bidirectional conducting device under test is determined, it is determined to be a failure.

4. The fatigue characteristic testing method for bidirectional conductive devices according to any one of claims 1-3, characterized in that, The pulse signal is a positive and negative pulse signal; at this time, the number of times the bidirectional conducting device under test is turned on is the number of pulse signals emitted by the pulse generator.

5. The fatigue characteristic testing method for bidirectional conductive devices according to any one of claims 1-3, characterized in that, The pulse signal is a unidirectional pulse signal; at this time, the number of times the bidirectional conducting device under test is turned on is twice the number of pulse signals emitted by the pulse generator.

6. The fatigue characteristic testing method for bidirectional conductive devices according to any one of claims 1-3, characterized in that, The pulse width of the pulse signal is 2 to 3 times the turn-on time of the bidirectional conducting device under test.

7. A fatigue characteristic testing device for a bidirectional conductive device, characterized in that, include: A pulse generator is connected to one end of the bidirectional conductive device under test and is used to send continuous pulse signals to the bidirectional conductive device under test. A capacitor, one end of which is connected to the other end of the bidirectional conductive device under test, and the other end is grounded; The test module is used to detect the voltage V across the capacitor. C When the voltage V C Not satisfied Under certain conditions, based on the number of pulse signals emitted by the pulse generator, the number of times the bidirectional conducting device under test is turned on is obtained; Wherein, the amplitude of the pulse signal is greater than the threshold voltage of the bidirectional conducting device under test, and the pulse width is greater than the turn-on time of the bidirectional conducting device under test; V0 is the amplitude of the pulse signal; R OFF X is the off-state resistance of the bidirectional conducting device under test; C Let be the capacitive impedance of the capacitor.

8. The fatigue characteristic testing device for bidirectional conductive devices according to claim 7, characterized in that, The capacitance C of the capacitor is selected based on the magnitude I of the current when the bidirectional conducting device under test is actually working and the signal output frequency f of the pulse generator; The capacitor C, the current magnitude I, and the signal output frequency f satisfy the following relationship: Among them, R ON The on-state resistance of the bidirectional conductive device under test is given.

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