Test circuit, test method and chip

Abstract

The invention discloses a test circuit, a test method and a chip, and the test circuit comprises a protected module which is suitable for outputting a performance parameter of the protected module when a performance test signal is loaded; and the electrostatic discharge module is coupled with the protected module, is arranged in parallel with the protected module, and is suitable for being conducted when the electrostatic discharge test signal is loaded so as to discharge the electrostatic current. According to the electrostatic discharge module, when the electrostatic discharge test signal is loaded, the effect of reducing damage of electrostatic current to the protected module can be achieved, that is, when the electrostatic discharge test signal is loaded, not only can the electrical performance of the electrostatic discharge module be tested, but also the protection effect of the electrostatic discharge module to the protected module can be tested; therefore, the practical application scene of the electrostatic discharge module can be well simulated, the reliability of the test circuit can be improved, and the reliability of the test result can be improved.

Description

Technical Field

[0001] Embodiments of the present invention relate to the field of semiconductor manufacturing, and in particular, to a test circuit, a test method, and a chip. Background Art

[0002] Static electricity is an objective natural phenomenon that can be generated in various ways, such as contact, friction, and induction between electrical appliances. Static electricity has the characteristics of long-term accumulation, high voltage, low power, small current, and short action time.

[0003] For electronic products, electrostatic discharge (ESD) is a major factor affecting the reliability of integrated circuits. ESD is a rapid charge neutralization process. Since the static electricity voltage is very high, it will bring destructive consequences to the integrated circuit and cause the failure of the integrated circuit. Therefore, in order to protect the integrated circuit from ESD damage, ESD protection devices are also designed in the integrated circuit to prevent the integrated circuit from being damaged by ESD. Correspondingly, the ESD protection devices will also be tested to obtain relevant test results, so as to ensure that the ESD protection devices can meet the design requirements.

[0004] However, the reliability of the test results of current ESD protection devices still needs to be improved. Summary of the Invention

[0005] The problem solved by the embodiments of the present invention is to provide a test circuit, a test method, and a chip to improve the reliability of test results.

[0006] To solve the above problems, embodiments of the present invention provide a test circuit, including: a protected module, adapted to output performance parameters of the protected module when a performance test signal is loaded; an electrostatic discharge module, coupled to the protected module and arranged in parallel, adapted to conduct when an electrostatic discharge test signal is loaded to discharge the electrostatic current.

[0007] Optionally, the protected module includes one or more of a metal oxide semiconductor field effect transistor, a bipolar transistor, and a resistor.

[0008] Optionally, the electrostatic discharge module includes one or more of a gate-grounded N-channel metal oxide semiconductor field effect transistor, a gate-connected power supply P-channel metal oxide semiconductor field effect transistor, a bipolar transistor, a Zener diode, and a common diode.

[0009] Optionally, the number of the protected modules is one or more.

[0010] Optionally, the number of the protected modules is multiple, and the multiple protected modules are arranged in parallel or in series.

[0011] Optionally, the number of the electrostatic discharge modules is one or more.

[0012] Optionally, the number of the electrostatic discharge modules is multiple, and the electrostatic discharge modules are arranged in parallel with each other.

[0013] Optionally, the protected module includes a first power signal loading terminal, the electrostatic discharge module includes a second power signal loading terminal, and the test circuit further includes: a resistor having a first end and a second end, the first end being coupled to the first power signal loading terminal, and the second end being coupled to the second power signal loading terminal.

[0014] Correspondingly, an embodiment of the present invention further provides a chip including the test circuit provided by the embodiment of the present invention.

[0015] Correspondingly, an embodiment of the present invention further provides a test method suitable for testing the test circuit provided by the embodiment of the present invention. The test method includes: loading a performance test signal to the protected module to perform an initial performance test so as to output initial performance parameters of the protected module; after the initial performance test, performing a protection ability test, where the protection ability test includes: loading an electrostatic discharge test signal to the electrostatic discharge module to perform an electrostatic current discharge test; after the electrostatic current discharge test, loading a performance test signal to the protected module to perform a final state performance test so as to output final state performance parameters of the protected module; determining whether a difference between the initial performance parameters and the final state performance parameters is within a range of a test error, and if so, increasing the electrostatic discharge test signal and repeating the protection ability test, otherwise, completing the evaluation of the protection ability of the electrostatic discharge module.

[0016] Optionally, the number of times of performing the protection ability test is greater than or equal to 10 times.

[0017] Compared with the prior art, the technical solution of the embodiment of the present invention has the following advantages:

[0018] In the test circuit provided by the embodiment of the present invention, a protected module and an electrostatic discharge module connected in parallel with the protected module are included, so that when an electrostatic discharge test signal is loaded, the electrostatic discharge module can play a role in reducing damage to the protected module caused by the electrostatic current. That is to say, when the electrostatic discharge test signal is loaded, not only the electrical performance of the electrostatic discharge module can be tested, but also the protection effect of the electrostatic discharge module on the protected module can be tested, thereby being able to better simulate the actual application scenario of the electrostatic discharge module, being beneficial to improving the reliability of the test circuit, and further being beneficial to improving the reliability of the test result.

[0019] In the test method provided by the embodiment of the present invention, an initial performance test is first performed to output initial performance parameters, and then a protection ability test is performed. The protection ability test includes an electrostatic current discharge test and a final state performance test performed in sequence to output final state performance parameters. It is judged whether the difference between the initial performance parameters and the final state performance parameters is within the range of test errors. If so, the electrostatic discharge test signal is increased and the protection ability test is repeated. Otherwise, the evaluation of the protection ability of the electrostatic discharge module is completed. Since the electrostatic discharge module of the test circuit is connected in parallel with the protected module, when the electrostatic discharge test signal is loaded, the electrostatic discharge module can play a role in reducing the damage caused by the electrostatic current to the protected module. That is to say, when the electrostatic discharge test signal is loaded, not only the electrical performance of the electrostatic discharge module can be tested, but also the protection effect of the electrostatic discharge module on the protected module can be tested, so that the actual application scenario of the electrostatic discharge module can be better simulated, which is beneficial to improving the reliability of the test circuit and further beneficial to improving the reliability of the test results. Description of the Drawings

[0020] Figure 1 is a schematic structural diagram of a test circuit;

[0021] Figure 2 is a schematic framework diagram of an embodiment of the test circuit of the present invention;

[0022] Figure 3 is a schematic circuit diagram of an embodiment of the test circuit of the present invention;

[0023] Figure 4 is a schematic flow diagram corresponding to an embodiment of the test method of the present invention. Detailed Embodiments

[0024] At present, the reliability of the test results still needs to be improved. Now, in combination with a test circuit, the reasons why the reliability of the test results still needs to be improved are analyzed. Figure 1 is a schematic structural diagram of a test circuit.

[0025] Reference Figure 1 , the test circuit 1 includes: an electrostatic discharge module 2, which is adapted to conduct when an electrostatic discharge test signal is loaded to discharge the electrostatic current.

[0026] This test structure is used to test the performance of the electrostatic discharge module 2. However, the test results of the performance of the electrostatic discharge module 2 cannot accurately characterize the actual protection ability of the electrostatic discharge module 2 to the protected device.

[0027] It has been found through research that in practical applications, due to various reasons (such as process fluctuations, etc.), the protection capabilities of ESD devices often vary. Since ESD is an instantaneous large current, these differences may lead to poor protection effects of ESD devices, resulting in damage to the protected devices. Moreover, conventional test circuits cannot evaluate the actual protection effect of ESD devices on the protected devices, thus making the reliability of test results to be improved.

[0028] To solve the above technical problems, an embodiment of the present invention provides a test circuit, including: a protected module, which is adapted to output the performance parameters of the protected module when loading a performance test signal; an electrostatic discharge module, which is coupled to and arranged in parallel with the protected module, and is adapted to conduct when loading an electrostatic discharge test signal to discharge the electrostatic current.

[0029] In the test circuit provided by the embodiment of the present invention, it includes a protected module and an electrostatic discharge module in parallel with the protected module, so that when loading an electrostatic discharge test signal, the electrostatic discharge module can play a role in reducing the damage caused by the electrostatic current to the protected module. That is to say, when loading an electrostatic discharge test signal, it can not only test the electrical performance of the electrostatic discharge module, but also test the protection effect of the electrostatic discharge module on the protected module, thus being able to better simulate the actual application scenario of the electrostatic discharge module, which is beneficial to improving the reliability of the test circuit and further beneficial to improving the reliability of test results.

[0030] In order to make the above objects, features, and advantages of the embodiments of the present invention more obvious and understandable, the following will describe the specific embodiments of the present invention in detail with reference to the accompanying drawings.

[0031] Figure 2 is a schematic diagram of the frame structure of an embodiment of the test circuit of the present invention; Figure 3 is a schematic diagram of the circuit structure of an embodiment of the test circuit of the present invention.

[0032] Refer to Figures 2 to 3 In this embodiment, the test circuit 10 includes: a protected module 100, which is adapted to output the performance parameters of the protected module 100 when loading a performance test signal; an electrostatic discharge module 101, which is coupled to and arranged in parallel with the protected module 100, and is adapted to conduct when loading an electrostatic discharge test signal to discharge the electrostatic current I total for discharge.

[0033] Since the electrostatic discharge module 101 of the test circuit is in parallel with the protected module 100, when loading an electrostatic discharge test signal, the electrostatic discharge module 101 can play a role in reducing the protection electrostatic current I totalThe effect of damaging the protected module 100, that is, when loading an electrostatic discharge test signal, not only can the electrical performance of the electrostatic discharge module 101 be tested, but also the protection effect of the electrostatic discharge module 101 on the protected module 100 (i.e., the discharge performance of the electrostatic discharge module 101) can be tested, so that the actual application scenario of the electrostatic discharge module 101 can be better simulated, which is beneficial to improving the reliability of the test circuit 10 and further beneficial to improving the reliability of the test results.

[0034] First, a performance test signal is loaded onto the protected module 100 to perform an initial performance test, so as to output the initial performance parameters of the protected module 100. At this time, the current flowing through the protected module 100 is the working current I of the protected module 100. device And the electrostatic discharge module 101 does not work when performing a performance test on the protected module 100, that is, when loading a performance test signal, the working current I of the protected module 100 device does not flow through the electrostatic discharge module 101.

[0035] Then, an electrostatic discharge test signal is loaded onto the electrostatic discharge module 101 to perform an electrostatic current discharge test to discharge the electrostatic current I. total for discharging.

[0036] It should be noted that when an electrostatic discharge test signal is loaded and the electrostatic discharge module 101 has sufficient discharge ability for the electrostatic current I, total the electrostatic discharge module 101 conducts to form a low-resistance path, so that all of the electrostatic current I total can be discharged through the electrostatic discharge module 101. Therefore, the current I flowing through the protected module 100 1 is zero, that is, the electrostatic current I total is equal to the current I flowing through the electrostatic discharge module 101, esd so that the protected module 100 will not be impacted and the protected module 100 is protected; when an electrostatic discharge test signal is loaded and the electrostatic discharge module 101 has insufficient discharge ability for the electrostatic current I, total part of the electrostatic current I total (i.e., the current I flowing through the electrostatic discharge module 101 esd ) is discharged through the electrostatic discharge module 101, and the remaining electrostatic current I total (i.e., the current I flowing through the protected module 100 1 ) is discharged through the protected module 100, thus impacting the protected module 100 and causing the protected module 100 to be damaged.

[0037] It should also be noted that when the protected module 100 is damaged, a performance test signal is loaded onto the protected module 100, and there will be a large difference between the output final performance parameters and the initial performance parameters, that is, the difference between the final performance parameters and the initial performance parameters is not within the range of the test error.

[0038] Therefore, after the static current discharge test, a performance test signal is loaded onto the protected module 100 to perform a final performance test to output the final performance parameters of the protected module 100. When the difference between the initial performance parameters and the final performance parameters is within the range of the test error, the electrostatic discharge test signal is increased and the protection ability test is repeated; when the difference between the initial performance parameters and the final performance parameters is not within the range of the test error, the evaluation of the protection ability of the electrostatic discharge module 101 is completed.

[0039] Among them, the test error is determined by the accuracy of the test machine. The difference between the initial performance parameters and the final performance parameters being within the range of the test error here means that the difference between the initial performance parameters and the final performance parameters is less than or equal to the lower limit value of the accuracy of the test machine. Therefore, the difference between the initial performance parameters and the final performance parameters being within the range of the test error means that the initial performance parameters are equal to or close to the final performance parameters, and the difference between the initial performance parameters and the final performance parameters not being within the range of the test error means that the difference between the initial performance parameters and the final performance parameters is large.

[0040] It can be seen that the test circuit 10 includes a first test branch (not labeled) and a second test branch (not labeled) connected in parallel with each other. The first test branch includes the protected module 100, and the second test branch includes the electrostatic discharge module 101. By the first test branch (not labeled) and the second test branch connected in parallel with each other, the performance of the protected module 100 in the first test branch and the performance of the electrostatic discharge module 101 in the second test branch can be tested respectively.

[0041] The protected module 100 is a module that needs to be protected by the electrostatic discharge module 101 to prevent it from being damaged due to electrostatic discharge.

[0042] Specifically, the protected module 100 includes electronic components or devices that need to be protected from electrostatic discharge damage. For example, the protected module 100 includes one or more of a metal oxide semiconductor field effect transistor, a bipolar transistor, and a resistor.

[0043] In this embodiment, the protected module 100 is a metal-oxide-semiconductor field-effect transistor (MOSFET). Metal-oxide-semiconductor field-effect transistors have the characteristics of good temperature stability, low noise, low power consumption, and easy integration, and are therefore widely used in integrated circuits. As an example, the metal-oxide-semiconductor field-effect transistor is an N-channel metal-oxide-semiconductor (NMOS) field-effect transistor.

[0044] In this embodiment, the protected module 100 includes a first power signal loading terminal H1.

[0045] The first power signal loading terminal H1 is used to load a power supply voltage signal during performance testing.

[0046] It should be noted that the protected module 100 further includes a first grounding terminal L1.

[0047] The first grounding terminal L1 is used to load a grounding voltage signal during performance testing.

[0048] It can be understood that the protected module 100 is coupled between the voltage source signal and the grounding voltage signal. That is to say, the power supply voltage signal loaded on the first power signal loading terminal H1 and the grounding voltage signal loaded on the first grounding terminal L1 are used as performance test signals for the protected module 100.

[0049] As Figure 3 shown, as an example, the protected module 100 is an N-channel metal-oxide-semiconductor field-effect transistor; correspondingly, the N-channel metal-oxide-semiconductor field-effect transistor has a drain D, a source S, a base B, and a gate G; wherein, the drain D serves as the first power signal loading terminal H1 for loading a power supply voltage signal, the source S and the base B serve as the first grounding terminal L1 for loading a grounding voltage signal, and the gate G loads different voltage signals (for example: a positive voltage signal or a zero voltage signal) according to the actual application requirements of the N-channel metal-oxide-semiconductor field-effect transistor.

[0050] It should be noted that in this embodiment, the power supply voltage loaded on the drain D is a positive voltage. In other embodiments, when the protected module is a P-channel metal-oxide-semiconductor field-effect transistor, the power supply voltage loaded on the drain is a negative voltage.

[0051] In this embodiment, the number of the protected modules 100 is one or more.

[0052] Since integrated circuits are easily damaged by static electricity, in order to reduce the probability of integrated circuit failure, the number of the protected modules 100 needs to be set according to actual requirements.

[0053] As an example, the number of the protected modules 100 is one.

[0054] In other embodiments, the number of the protected modules is plural, and the plural protected modules are arranged in parallel or in series.

[0055] Generally, in order to implement a certain function, it is often necessary to arrange multiple functional modules in parallel or in series. To prevent the above-mentioned multiple functional modules from being damaged by static electricity, it is necessary to perform electrostatic discharge protection on the above-mentioned multiple functional modules. For this reason, the number of the protected modules is plural, and the plural protected modules are arranged in parallel or in series.

[0056] The electrostatic discharge module 101 is a module for performing electrostatic discharge protection on the protected module 100 to prevent the protected module 100 from being damaged by electrostatic discharge.

[0057] Specifically, the electrostatic discharge module 101 includes one or more of a gate-grounded N-channel metal oxide semiconductor (GGNMOS) field effect transistor, a gate-to-drain P-channel metal oxide semiconductor (GDPMOS) field effect transistor, a bipolar transistor, a Zener diode, and a common diode. Among them, the common diode is a semiconductor device formed by a PN structure.

[0058] In this embodiment, the electrostatic discharge module 101 is a gate-grounded N-channel metal oxide semiconductor field effect transistor (as Figure 3 shown).

[0059] In this embodiment, the electrostatic discharge module 101 includes a second power signal loading terminal H2.

[0060] The second power signal loading terminal H2 is used to load a pulse voltage signal during the electrostatic current I total discharge test.

[0061] It should be noted that the electrostatic discharge module 101 further includes a second grounding terminal L2.

[0062] The second grounding terminal L2 is used to load a grounding voltage signal during the electrostatic current I total discharge test.

[0063] It can be understood that the electrostatic discharge module 101 is coupled between the power supply voltage signal and the ground voltage signal. That is to say, the pulse voltage signal applied to the second power signal loading terminal H2 and the ground voltage signal applied to the second ground terminal L2 are used as the electrostatic discharge test signal applied to the electrostatic discharge module 101. When the electrostatic discharge test signal is applied, the electrostatic discharge module 101 conducts to discharge the electrostatic current I total ; and when the performance test signal is applied, the electrostatic discharge module 101 does not work. That is, when the performance test signal is applied, the working current I of the protected module 100 device does not flow through the electrostatic discharge module 101 to perform a performance test on the protected module 100.

[0064] Since applying the electrostatic discharge test signal to the electrostatic discharge module 101 is for discharging test of the electrostatic current I total and applying the performance test signal to the protected module 100 is to obtain the initial performance parameters of the protected module 100 before the electrostatic current I total discharging test, and to obtain the final performance parameters of the protected module 100 after the electrostatic current I total discharging test. When the difference between the initial performance parameters and the final performance parameters is within the range of the test error, increase the electrostatic discharge test signal and sequentially repeat the protection ability test and the final performance test. When the difference between the initial performance parameters and the final performance parameters is not within the range of the test error, complete the evaluation of the protection ability of the electrostatic discharge module.

[0065] In this embodiment, the number of the electrostatic discharge modules 101 is one or more.

[0066] To ensure the protection effect on the protected module 100 and reduce the probability of integrated circuit failure, it is necessary to set the number of the electrostatic discharge modules 101 according to actual requirements.

[0067] In a specific embodiment, the number of the electrostatic discharge modules 101 is one.

[0068] In another specific embodiment, the number of the electrostatic discharge modules 101 is multiple, and the electrostatic discharge modules 101 are arranged in parallel.

[0069] The electrostatic discharge modules 101 are arranged in parallel, that is, multiple electrostatic discharge modules 101 can all play a role in protecting the protected module 100 from the electrostatic current I total so that the protection effect of the electrostatic discharge module 101 on the protected module 100 is better.

[0070] In this embodiment, the first test branch further includes a resistor 103. The resistor 103 has a first end 1031 and a second end 1032. The first end 1031 is coupled to the first power signal loading terminal H1, and the second end 1032 is coupled to the second power signal loading terminal H2 (as Figure 2 and Figure 3 shown).

[0071] Correspondingly, the test circuit 10 also further includes the resistor 103.

[0072] During the electrostatic current I total discharge test, when the electrostatic discharge module 101 has insufficient discharge capacity for the electrostatic current I total , and part of the electrostatic current I total is discharged through the electrostatic discharge module 101, and the remaining electrostatic current I total is discharged through the protected module 100, the resistor 103 can play a certain voltage-dividing role, thereby reducing the current impact on the protected module 100, and further reducing the probability of the protected module 100 being damaged by electrostatic discharge. Correspondingly, the application range of the electrostatic discharge module 101 is also expanded.

[0073] Moreover, in practical applications, the protected module 100 is usually also connected in series with the resistor 103. Therefore, the first end 1031 of the resistor 103 is coupled to the first power signal loading terminal H1, and the second end 1032 of the resistor 103 is coupled to the second power signal loading terminal H2, which can better simulate the actual application scenario.

[0074] In this embodiment, the resistor 103 can be a single resistor or a resistor module formed by connecting multiple resistors in series or in parallel. The present application does not limit this.

[0075] Correspondingly, the present invention also provides a test method suitable for testing the aforementioned test circuit. Figure 4 is a schematic flowchart corresponding to an embodiment of the test method of the present invention. The test method of this embodiment will be described in detail below with reference to the accompanying drawings.

[0076] It should be noted that for the detailed description of the aforementioned test circuit, please refer to the corresponding description in the previous part, and details will not be repeated here.

[0077] Refer to Figure 2 and 4 , and perform step S1: Load a performance test signal on the protected module 100 to perform an initial performance test to output the initial performance parameters of the protected module 100.

[0078] By obtaining initial performance parameters for comparison with the final performance parameters obtained subsequently, the parameter value changes of the electrostatic discharge module 101 before and after the electrostatic current I total discharge test are detected.

[0079] Load a performance test signal on the protected module 100 to perform an initial performance test to output the initial performance parameters of the protected module 100. At this time, the current flowing through the protected module 100 is the working current I device (as Figure 2 shown); since the loaded performance test signal is for outputting the performance parameters of the protected module 100, the electrostatic discharge module 101 does not work at this time, that is, when the performance test signal is loaded, the working current I device of the protected module 100 does not flow through the electrostatic discharge module 101 to perform a performance test on the protected module 100.

[0080] In this embodiment, the protected module 100 includes a first power signal loading terminal H1.

[0081] The first power signal loading terminal H1 is used to load a power supply voltage signal during the performance test.

[0082] It should be noted that the protected module 100 further includes a first grounding terminal L1.

[0083] The first grounding terminal L1 is used to load a grounding voltage signal during the performance test.

[0084] It can be understood that the protected module 100 is coupled between the voltage source signal and the grounding voltage signal. That is to say, the power supply voltage signal loaded on the first power signal loading terminal H1 and the grounding voltage signal loaded on the first grounding terminal L1 are used as the performance test signals loaded on the protected module 100.

[0085] In this embodiment, the initial performance parameters can be current, resistance, or other parameters that can characterize the electrical performance of the protected module. As an example, the initial performance parameter is current.

[0086] Refer to Figure 2 and 4 , execute step S2: After the initial performance test, perform a protection ability test. The protection ability test includes: loading an electrostatic discharge test signal on the electrostatic discharge module 101 to perform an electrostatic current I total discharge test; after the electrostatic current I total discharge test, load a performance test signal on the protected module 100 to perform a final performance test to output the final performance parameters of the protected module 100.

[0087] Apply an electrostatic discharge test signal to the electrostatic discharge module 101 to conduct an electrostatic current discharge test for the electrostatic current I total for discharging.

[0088] It should be noted that when an electrostatic discharge test signal is applied and the electrostatic discharge module 101 has sufficient discharge capacity for the electrostatic current I total the electrostatic discharge module 101 conducts to form a low-resistance path, enabling the electrostatic current I total to be discharged through the electrostatic discharge module 101. Therefore, the current I flowing through the protected module 100 1 is zero, that is, the electrostatic current I tota is equal to the current I flowing through the electrostatic discharge module 101 esd , thus not impacting the protected module 100, and the protected module 100 is protected; when an electrostatic discharge test signal is applied and the electrostatic discharge module 101 has insufficient discharge capacity for the electrostatic current I total part of the electrostatic current I total (i.e., the current I flowing through the electrostatic discharge module 101 esd ) is discharged through the electrostatic discharge module 101, and the remaining electrostatic current I total (i.e., the current I flowing through the protected module 100 1 ) is discharged through the protected module 100, thereby impacting the protected module 100 and causing damage to the protected module 100.

[0089] In this embodiment, the electrostatic discharge module 101 includes a second power supply signal loading terminal H2.

[0090] The second power supply signal loading terminal H2 is used to load a pulse voltage signal during the electrostatic current I total discharge test.

[0091] It should be noted that the electrostatic discharge module 101 further includes a second grounding terminal L2.

[0092] The second grounding terminal L2 is used to load a grounding voltage signal during the electrostatic current I total discharge test.

[0093] It can be understood that the electrostatic discharge module 101 is coupled between the power supply voltage signal and the grounding voltage signal. That is to say, the pulse voltage signal loaded on the second power supply signal loading terminal H2 and the grounding voltage signal loaded on the second grounding terminal L2 are used as the electrostatic discharge test signal applied to the electrostatic discharge module 101. When the electrostatic discharge test signal is applied, the electrostatic discharge module 101 conducts to discharge the electrostatic current I tota for discharging.

[0094] Since the purpose of loading an electrostatic discharge test signal to the electrostatic discharge module 101 is to conduct an electrostatic current I total discharge test, and the purpose of loading a performance test signal to the protected module 100 is to obtain the initial performance parameters of the protected module 100 before the electrostatic current I total discharge test, and to obtain the final performance parameters of the protected module 100 after the electrostatic current I total discharge test. When the difference between the initial performance parameters and the final performance parameters is within the range of the test error, increase the electrostatic discharge test signal and repeat the protection ability test and the final performance test in sequence. When the difference between the initial performance parameters and the final performance parameters is not within the range of the test error, complete the evaluation of the protection ability of the electrostatic discharge module. Therefore, when loading an electrostatic discharge test signal, the electrostatic discharge module 101 is turned on, and when loading a performance test signal, the electrostatic discharge module 101 does not work, that is, when loading a performance test signal, the working current I device of the protected module 100 does not flow through the electrostatic discharge module 101 to perform a performance test on the protected module 100.

[0095] In this embodiment, when conducting the electrostatic current I total discharge test, the first power signal loading terminal H1 is floating, and the first grounding terminal L1 is floating or loaded with a grounding voltage signal.

[0096] In this embodiment, the electrostatic current I total discharge test includes a Transmission Line Pulse (TLP) test.

[0097] Refer to Figure 4 , perform step S3: Determine whether the difference between the initial performance parameters and the final performance parameters is within the range of the test error.

[0098] Perform step S4: If so, increase the electrostatic discharge test signal and repeat the protection ability test.

[0099] It can be understood that repeating the protection ability test means: under the condition of increasing the electrostatic discharge test signal, perform step S2 again to conduct the protection ability test.

[0100] Perform step S5: Otherwise, complete the evaluation of the protection ability of the electrostatic discharge module.

[0101] When the protected module 100 is damaged, a performance test signal is loaded onto the protected module 100, and there will be a large difference between the output final performance parameters and the initial performance parameters, that is, the difference between the final performance parameters and the initial performance parameters is not within the range of the test error.

[0102] Therefore, after the static current discharge test, a performance test signal is loaded onto the protected module 100 to conduct a final performance test to output the final performance parameters of the protected module. When the difference between the initial performance parameters and the final performance parameters is within the range of the test error, the static discharge test signal is increased and the protection ability test is repeated; when the difference between the initial performance parameters and the final performance parameters is not within the range of the test error, the evaluation of the protection ability of the static discharge module is completed.

[0103] Among them, the test error is determined by the accuracy of the test machine. The difference between the initial performance parameters and the final performance parameters being within the range of the test error here means that the difference between the initial performance parameters and the final performance parameters is less than or equal to the lower limit value of the accuracy of the test machine. Therefore, when the difference between the initial performance parameters and the final performance parameters is within the range of the test error, that is, the initial performance parameters are equal to or close to the final performance parameters; when the difference between the initial performance parameters and the final performance parameters is not within the range of the test error, that is, the difference between the initial performance parameters and the final performance parameters is large.

[0104] When the difference between the initial performance parameters and the final performance parameters is within the range of the test error, it indicates that the static discharge module 101 has sufficient discharge ability for the static current I total Therefore, the static discharge test signal can be increased and the protection ability test can be repeated to make a more accurate evaluation of the protection ability of the static discharge module 101. When the difference between the initial performance parameters and the final performance parameters is not within the range of the test error, it indicates that the static discharge module 101 has insufficient discharge ability for the static current I total At this time, the evaluation of the protection ability of the static discharge module 101 is completed, that is, the protection ability of the static discharge module 101 can be evaluated more accurately.

[0105] As an example, increasing the static discharge test signal means increasing the value of the pulse voltage signal, and correspondingly increasing the value of the static current I total value, so as to facilitate obtaining the maximum pulse voltage value that the static discharge module 101 can withstand, and correspondingly facilitating obtaining the maximum static current I total value that the static discharge module 101 can withstand, and then completing the evaluation of the protection ability of the static discharge module 101.

[0106] In this embodiment, the number of times of performing the protection ability test is greater than or equal to 10 times.

[0107] The number of times of performing the protection ability test being greater than or equal to 10 times is conducive to making the increase amplitude between the subsequent electrostatic discharge test signal and the previous electrostatic discharge test signal smaller, thereby being conducive to making the accuracy of evaluating the protection ability of the electrostatic discharge module 101 relatively ideal.

[0108] Although the present invention is disclosed as above, the present invention is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention should be subject to the scope defined by the claims.

Claims

1. A test circuit, characterized in that: include: The protected module is adapted to output the performance parameters of the protected module when a performance test signal is loaded; The electrostatic discharge module is coupled to the protected module and arranged in parallel, and is suitable for being turned on when an electrostatic discharge test signal is loaded to discharge the electrostatic current.

2. The test circuit according to claim 1, characterized in that: The protected module includes one or more of a metal oxide semiconductor field effect transistor, a bipolar transistor and a resistor.

3. The test circuit according to claim 1, characterized in that: The electrostatic discharge module includes one or more of a gate-grounded N-type channel metal oxide semiconductor field effect transistor, a gate-powered P-type channel metal oxide semiconductor field effect transistor, a bipolar transistor, a Zener diode and a common diode.

4. The test circuit according to claim 1, characterized in that: The number of the protected modules is one or more.

5. The test circuit according to claim 4, characterized in that: There are multiple protected modules, and the multiple protection modules are connected in parallel or in series.

6. The test circuit according to claim 1, characterized in that: The number of the electrostatic discharge module is one or more.

7. The test circuit according to claim 6, characterized in that: There are multiple electrostatic discharge modules, and each of the electrostatic discharge modules is arranged in parallel.

8. The test circuit according to any one of claims 1 to 7, characterized in that: The protected module includes a first power signal loading terminal, the electrostatic discharge module includes a second power signal loading terminal, and the test circuit also includes: a resistor, the resistor has a first end and a second end, the first end is coupled to the first power signal loading terminal, and the second end is coupled to the second power signal loading terminal.

9. A chip, characterized in that: The method comprises the test circuit as claimed in any one of claims 1 to 8.

10. A testing method, characterized in that: Suitable for testing the test circuit according to any one of claims 1 to 8, the test method comprising: Loading a performance test signal to the protected module to perform an initial performance test to output initial performance parameters of the protected module; After the initial performance test, a protection capability test is performed, and the protection capability test includes: loading an electrostatic discharge test signal on the electrostatic discharge module to perform an electrostatic current discharge test; after the electrostatic current discharge test, loading a performance test signal on the protected module to perform a final state performance test to output the final state performance parameters of the protected module; Determine whether the difference between the initial performance parameter and the final performance parameter is within the range of the test error. If so, increase the electrostatic discharge test signal and repeat the protection capability test; otherwise, complete the evaluation of the protection capability of the electrostatic discharge module.

11. The testing method according to claim 10, characterized in that: The protection capability test is performed for a number of times greater than or equal to 10 times.

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