A method for testing the voltage resistance of an MLCC and an MLCC testing machine

Abstract

The application discloses a voltage withstand test method of an MLCC, which is applied to a testing machine with a surge test function, and comprises the following steps: under the condition that a to-be-tested MLCC is located at a test position corresponding to a surge test, and a surge instrument is connected with the to-be-tested MLCC, a control device controls the surge instrument to detect the voltage change of the to-be-tested MLCC from an initial value to a target voltage value in a charging process, and the voltage maintaining condition of the to-be-tested MLCC after the charging is completed. The surge instrument provides information about whether the voltage withstand of the to-be-tested MLCC is qualified to the control device according to the voltage change of the to-be-tested MLCC. The control device determines whether the voltage withstand of the to-be-tested MLCC is qualified according to the information. The voltage withstand test of the to-be-tested MLCC in the testing machine is realized through the surge instrument in the MLCC testing machine, the defect of the to-be-tested MLCC can be effectively detected, the precision of the test is greatly improved, and the safety hidden danger of the MLCC is excluded.

Description

Technical Field

[0001] This application relates to the field of capacitor testing technology, and in particular to a method for testing the withstand voltage of MLCCs and an MLCC testing machine. Background Technology

[0002] Against the backdrop of significant advancements in 5G terminal equipment and the smart electric vehicle industry, the domestic multilayer ceramic capacitor (MLCC) industry has experienced rapid development, simultaneously driving the growth of domestically produced equipment based on MLCC manufacturing. However, due to its relatively late start, many testing functions for MLCCs are still under further research compared to imported equipment.

[0003] In existing technologies, domestically produced MLCC testing machines can only test parameters such as capacitance, loss, and insulation. The withstand voltage parameter of MLCCs is typically tested separately using a withstand voltage instrument. The principle is that the withstand voltage instrument is set with parameters such as the theoretical withstand voltage, breakdown current, and power-on time of the MLCC product. An internal timer starts timing and outputs the set voltage. If the output current exceeds the set breakdown current within the set time, it is judged as a withstand voltage failure.

[0004] The drawbacks of using withstand voltage gauges include long testing times, low sensitivity to breakdown current, and inability to detect minor defects such as poor withstand voltage. Furthermore, due to their long testing times and low sensitivity, they are not suitable for installation on high-efficiency MLCC testing machines. Summary of the Invention

[0005] This application provides a method for testing the withstand voltage of MLCCs and an MLCC testing machine, which enables the withstand voltage testing of MLCCs, which originally required separate withstand voltage instruments, to be performed directly on the testing machine, greatly shortening the testing time and improving testing efficiency and accuracy.

[0006] The technical solution is as follows:

[0007] Firstly, a withstand voltage test method for MLCCs is provided, applicable to a test machine equipped with surge meters and control devices. The method includes:

[0008] When the MLCC under test is located at the test position corresponding to the surge meter, and the surge meter is connected to the MLCC under test, the control device controls the surge meter to detect the first voltage change and the second voltage change of the MLCC under test.

[0009] The first voltage change condition is used to reflect the change in the voltage of the to-be-tested MLCC from an initial value to a target voltage value during the charging process of the to-be-tested MLCC, and the second voltage change condition is used to reflect the voltage change of the to-be-tested MLCC during a first time period from the end of the charging moment until the voltage drops from the target voltage value to a preset value;

[0010] The surge meter provides information reflecting whether the withstand voltage of the to-be-tested MLCC is qualified to the control device according to the first voltage change condition and the second voltage change condition;

[0011] The control device determines whether the withstand voltage of the to-be-tested MLCC is qualified according to the information.

[0012] In this application, by adding a customized meter, i.e., a surge meter, to the MLCC tester, the withstand voltage test of the MLCC can be completed in the tester. The control device in the tester controls the surge meter to charge the to-be-tested MLCC, determines the information for judging the withstand voltage according to the change of the voltage of the to-be-tested sample over time within a preset time period, and the controller determines whether the withstand voltage of the to-be-tested MLCC is qualified according to the information. This solution realizes the withstand voltage test of the MLCC in the tester through the surge meter in the MLCC tester, can effectively detect the defect points of the to-be-tested MLCC, greatly improves the accuracy of the test, and eliminates the safety hazards of the MLCC.

[0013] Optionally, the control device controls the surge meter to detect the first voltage change condition and the second voltage change condition of the to-be-tested MLCC, including:

[0014] The control device sends a start test instruction to the surge meter;

[0015] In response to the start test instruction, the surge meter charges the to-be-tested MLCC with a specified charging voltage within a charging time period, and collects the voltage values of the to-be-tested MLCC at different time points within the charging time period to obtain the first voltage change condition;

[0016] The surge meter collects the voltage values of the to-be-tested MLCC at different time points within the first time period to obtain the second voltage change condition,

[0017] The first time period includes the voltage holding time period of the to-be-tested MLCC and the time period during which the voltage of the to-be-tested MLCC drops from the target voltage value to a preset value, and the starting moment of the first time period is the end of the charging moment.

[0018] Optionally, before the control device sends a start test instruction to the surge meter, the method further includes:

[0019] The control device provides the surge meter with charging parameters for charging the MLCC under test based on the user's input operation. The charging parameters include the specified charging voltage when the surge meter charges the MLCC under test and information for determining the charging time period.

[0020] Optionally, the surge meter determines information reflecting the withstand voltage of the MLCC under test based on the first voltage change and the second voltage change, including:

[0021] The surge meter obtains the test waveform of the MLCC under test based on the first voltage change and the second voltage change. The test waveform is used to reflect the voltage change of the MLCC under test over time during the charging period, the voltage holding period, and the voltage drop period.

[0022] The surge meter compares the test waveform with a standard waveform to obtain information reflecting the withstand voltage of the MLCC under test. The standard waveform reflects the voltage change over time of the standard MLCC during the charging period, the holding period, and the voltage drop period.

[0023] Optionally, before testing the withstand voltage of the MLCC under test, the method includes:

[0024] The surge meter outputs a first voltage to charge the standard MLCC during the charging period and records the voltage value of the standard MLCC at different time points during the charging period.

[0025] Starting from the end of charging of the standard MLCC, the surge meter determines the voltage holding time of the standard MLCC, and the voltage value of the standard MLCC at different time points during the voltage drop time after the voltage holding time.

[0026] The standard waveform is obtained based on the voltage values ​​at different time points within the charging time period, the voltage holding time period, and the voltage drop time period.

[0027] Wherein, the first voltage is the maximum voltage that the standard MLCC can withstand.

[0028] The standard MLCC is an MLCC that meets the pressure resistance requirements, and the specifications of the MLCC are the same as those of the MLCC under test.

[0029] Optionally, the surge meter compares the test waveform with a standard waveform to obtain information reflecting the withstand voltage of the sample under test, including:

[0030] If the surge meter determines that the error between the test waveform and the standard waveform is within a preset range, then the withstand voltage of the MLCC under test is deemed qualified.

[0031] If the surge meter determines that the error between the test waveform and the standard waveform is outside the preset range, then the withstand voltage test is deemed unqualified.

[0032] By comparing the waveforms of the MLCC under test with those of qualified MLCCs through surge testing, the accuracy of withstand voltage testing is improved.

[0033] Optionally, the MLCC testing machine has a display device. When the withstand voltage of the MLCC under test is determined to be qualified, the display device displays information indicating that the withstand voltage of the MLCC under test is qualified; when the withstand voltage of the MLCC under test is determined to be unqualified, the display device displays information indicating that the withstand voltage of the MLCC under test is unqualified.

[0034] The changes in the MLCC waveform, including the voltage value at each time point, can be observed intuitively through the display device on the testing machine.

[0035] Optionally, the MLCC testing machine further includes one or more testing instruments, which are connected to the control device. The method further includes:

[0036] The control device determines whether the first performance parameter of the MLCC under test is qualified through one or more of the test instruments. Different test instruments measure different performance parameters. The first performance parameter is the performance parameter of the MLCC under test other than the withstand voltage.

[0037] Based on the information from the first instrument surge meter indicating whether the withstand voltage of the MLCC under test is qualified, and the indication information from one or more of the test instruments indicating whether the first performance parameter of the MLCC under test is qualified, the control device transmits the MLCC under test to the corresponding sorting and receiving box.

[0038] Optionally, the MLCC testing machine is also connected to a moving device for moving the capacitor, and the method further includes:

[0039] The control device determines the test position of each of the test instruments and the surge instrument;

[0040] The testing sequence is determined based on the test position of each of the test instruments and the surge instrument;

[0041] The control device controls the mobile device to pass through the test positions of each of the test instruments and the surge instrument in the order of detection.

[0042] Secondly, an MLCC testing machine is provided, including a surge meter and a control device connected to the surge meter.

[0043] The control device is used to send a test command to the surge meter when it detects that the MLCC under test is located at the test position of the surge meter. The test command is used to detect the first voltage change and the second voltage change of the MLCC under test within a preset time period.

[0044] The surge meter is used to measure the voltage change of the MLCC under test within a preset time period according to the test command, and to provide the control device with information reflecting the withstand voltage of the MLCC under test based on the voltage change of the MLCC under test within the preset time period.

[0045] The control device is also used to determine whether the withstand voltage of the MLCC under test is qualified based on the information.

[0046] It is understandable that the beneficial effects of the second aspect mentioned above can be found in the relevant descriptions of the first aspect mentioned above, and will not be repeated here. Attached Figure Description

[0047] 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.

[0048] Figure 1 This is a flowchart of a pressure resistance test method for MLCCs provided in an embodiment of this application;

[0049] Figure 2 This is a schematic diagram of the structure of an MLCC testing machine provided in an embodiment of this application;

[0050] Figure 3 These are test waveforms and standard waveforms from a withstand voltage test method for MLCCs provided in this application embodiment;

[0051] Figure 4 These are waveform diagrams of MLCCs with and without withstand voltage, provided in the embodiments of this application.

[0052] Figure 5 This is a display interface for an MLCC testing machine provided in an embodiment of this application;

[0053] Figure 6 This is a schematic diagram of an MLCC testing machine with a withstand voltage tester and other test instruments provided in an embodiment of this application;

[0054] Figure 7 This is a schematic diagram of an MLCC testing machine with multiple testing instruments provided in an embodiment of this application. Detailed Implementation

[0055] To make the objectives, technical solutions, and advantages of this application clearer, the embodiments of this application will be described in further detail below with reference to the accompanying drawings.

[0056] It should be understood that "multiple" as mentioned in this application refers to two or more. In the description of this application, unless otherwise stated, " / " indicates "or," for example, A / B can mean A or B; "and / or" in this document is merely a description of the relationship between related objects, indicating that three relationships can exist, for example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Furthermore, to facilitate a clear description of the technical solutions of this application, the terms "first," "second," etc., are used to distinguish identical or similar items with essentially the same function and effect. Those skilled in the art will understand that the terms "first," "second," etc., do not limit the quantity or execution order, and that "first," "second," etc., do not necessarily imply differences.

[0057] Before providing a detailed explanation of the embodiments of this application, the application scenarios of these embodiments will be described first.

[0058] Currently, domestically produced MLCC testers can only test parameters such as capacitance, loss, and insulation of MLCCs. For withstand voltage parameters, the common practice is to use a separate withstand voltage tester to perform a secondary test on the MLCC. The principle is to set the theoretical withstand voltage, breakdown current, and energizing time of the MLCC under test within the withstand voltage tester. The tester's output is connected to the electrodes of the MLCC under test. When the tester is started, its internal timer begins timing and outputs the set voltage. If the output current exceeds the set breakdown current within the set time, it is considered a withstand voltage failure. The drawbacks of this method are the long test time, typically ranging from several seconds to tens of seconds depending on the product specifications; low sensitivity in detecting breakdown current; and inability to detect minor withstand voltage defects. Therefore, withstand voltage testers are not suitable for installation on high-efficiency MLCC testers.

[0059] The following is a detailed explanation of a pressure resistance test method for MLCCs provided in the embodiments of this application.

[0060] Figure 1A method for withstand voltage testing of MLCCs is provided, which is applied in an MLCC testing machine equipped with surge meters and control devices. The surge meters and control devices are communicatively connected.

[0061] Surge meters are instruments customized for testing the withstand voltage of MLCCs. The instruments need to conform to the relevant specifications of the MLCC tester and can be used in conjunction with other instruments in the MLCC tester, such as capacity bridge meters and high resistance insulation meters.

[0062] The control unit consists of the processor and related actuators of the MLCC tester. It receives, processes, and sends test commands input by the user, and operates the MLCC under test through the actuators. The processor can be a host computer or a programmable logic controller (PLC); no limitation is made here. As an example, the surge meter is connected to a host computer.

[0063] The pressure resistance testing method for MLCCs provided in this application includes:

[0064] Step 101: With the MLCC under test located at the corresponding test position of the surge meter, and the surge meter connected to the MLCC under test, the control device controls the surge meter to detect the first voltage change and the second voltage change of the MLCC under test. The first voltage change reflects the process of the MLCC under test's voltage rising from an initial value to a target voltage value during the charging process. The second voltage change determines the voltage holding condition of the MLCC under test after charging ends and the process of the voltage decreasing from the target voltage value to a preset value.

[0065] As an example, a surge meter has a voltage output terminal, and the MLCC under test (MDT) has a terminal. Connecting the surge meter to the MDT means connecting the voltage output terminal to the terminal. This allows the surge meter to provide voltage to the MDT for charging. When the MDT is in the test position of the surge meter, the processor in the control device (such as a host computer) controls the surge meter to rapidly charge the MDT. The voltage of the MDT rises from 0 to the voltage value provided by the surge meter. When the voltage value provided by the surge meter is reached, it is held for a period of time. After a period of stability, the voltage begins to drop, eventually reaching 0. This process is the second voltage change scenario.

[0066] For example, when using a testing machine to test various performance parameters of a to-be-tested MLCC, such as voltage withstand, insulation and other parameters, the to-be-tested MLCC can be installed on a mobile device (for example, the mobile device can include a carrier tray for carrying the to-be-tested MLCC), and then the mobile device can move from a first position to a test position where a surge meter is located under the control of a control device. This process can refer to the description in the prior art, and the embodiments of the present application do not make any limitations.

[0067] Step 102: The surge meter provides information reflecting whether the voltage withstand of the to-be-tested MLCC is qualified to the control device according to the voltage change situation of the to-be-tested MLCC.

[0068] Step 103: The control device determines whether the voltage withstand of the to-be-tested MLCC is qualified according to the information.

[0069] After the surge meter obtains the information, it transmits the information to the control device, and the processor in the control device determines whether the voltage withstand of the to-be-tested MLCC is qualified according to the information.

[0070] In an embodiment of the present application, as Figure 2 shown, the to-be-tested MLCC is located at the test position of the surge meter. The processor 201 sends a test instruction to the surge meter 202. The surge meter 202 charges, holds the voltage and then drops the voltage of the to-be-tested MLCC according to a preset voltage and a preset time, and obtains a curve of the voltage of the to-be-tested MLCC changing with time within the preset time period, that is, the first voltage change situation and the second voltage change situation. The surge meter compares the first voltage change situation and the second voltage change situation of a pre-set standard MLCC with those of the to-be-tested MLCC. When the comparison result shows that the two curves coincide within the error range, the surge meter 202 sends this information to the processor 201, and the processor 201 determines that the voltage withstand of the to-be-tested MLCC is qualified according to the information. When the comparison result shows that the two curves do not coincide within the error range, the surge meter 202 sends this information to the processor 201, and the processor 201 determines that the voltage withstand of the to-be-tested MLCC is unqualified according to the information.

[0071] In the present application, by customizing a meter for testing voltage withstand in an MLCC testing machine, the voltage withstand test of the MLCC can be completed in the testing machine. The control device in the testing machine controls the surge meter to charge the to-be-tested MLCC, and determines the information for judging the voltage withstand according to the change situation of the voltage of the to-be-tested sample with time within the preset time period. The controller determines whether the voltage withstand of the to-be-tested MLCC is qualified according to the information. This solution enables the voltage withstand test to be also carried out through the testing machine, without the need to test the voltage withstand of the MLCC through a separate voltage withstand test meter, greatly improving the testing efficiency.

[0072] In one embodiment of this application, the control device controls a surge meter to detect a first voltage change and a second voltage change of the MLCC under test, including: the control device sending a start test command to the surge meter; the surge meter responding to the start test command, charging the MLCC under test with a specified charging voltage during a charging period, and collecting the voltage value of the MLCC under test at different time points during the charging period to obtain the first voltage change; and after charging is completed, the surge meter collecting the voltage value of the MLCC under test at different time points during the first time period to obtain the second voltage change.

[0073] The first time period includes the voltage holding period of the MLCC under test and the period during which the voltage of the MLCC under test decreases from the target voltage value to the preset value. The voltage holding period is the time during which the voltage of the MLCC under test is maintained at the target voltage value after the voltage of the MLCC under test reaches the target voltage value.

[0074] For example, the start test command is sent from the host computer to the surge meter. Specifically, the host computer can send the start test command when it detects a user-triggered start test command or when the MLCC under test is located at the corresponding test position on the surge meter and the surge meter is connected to the MLCC under test. After charging stops, the MLCC under test undergoes a voltage holding phase and a voltage drop phase, and the surge meter collects the voltage change curve over time during this period.

[0075] In one embodiment of this application, before the control device sends a start test command to the surge meter, the method further includes: the control device providing charging parameters for charging the MLCC under test to the surge meter based on user input, the charging parameters including the charging voltage and charging time when the surge meter charges the MLCC under test. Optionally, the above charging parameters can also be set by default in the surge meter.

[0076] As an example, the user inputs charging parameters on the MLCC tester's interface, including the charging voltage and time for the MLCC under test, as well as the holding voltage time and voltage drop time. After input, the host computer of the MLCC tester sends the charging parameters to the surge meter, which then provides the test charging voltage and charging time for the MLCC under test based on the parameters.

[0077] In one embodiment of this application, a surge meter determines information reflecting the withstand voltage of the MLCC under test based on its voltage changes. This includes: the surge meter obtaining a test waveform of the MLCC under test based on a first voltage change and a second voltage change. The test waveform reflects the voltage change over time of the MLCC under test during the charging period, the holding period, and the voltage drop period. The surge meter compares the test waveform with a standard waveform to obtain information reflecting the withstand voltage of the MLCC under test. The standard waveform reflects the voltage change over time of a standard MLCC during the charging period, the holding period, and the voltage drop period.

[0078] The standard waveform can be a waveform input to the surge meter via an MLCC tester, or it can be a waveform obtained by testing a known standard MLCC with the surge meter. The obtained waveform is then stored in the surge meter for comparison with the waveform to be tested.

[0079] like Figure 3 Test waveforms and standard waveforms are provided, such as Figure 3 As shown, waveform 301 is the standard waveform, and waveform 302 is the test waveform. Taking the standard waveform 301 as an example, t0~t1 is the charging period, during which the surge meter rapidly charges the MLCC sample under test, and the voltage is the first voltage. At time t1, the voltage of the MLCC sample under test will theoretically reach the first voltage. t1~t2 is the voltage holding period, during which the voltage of the MLCC sample under test remains unchanged. t2~t3 is the voltage drop period, during which the voltage of the MLCC sample under test begins to decrease, and at time t3, the voltage drops to 0.

[0080] In one embodiment of this application, before testing the withstand voltage of the MLCC under test, the method includes: a surge meter outputting a first voltage to charge a standard MLCC during a charging period, and recording the voltage values ​​of the standard MLCC at different time points during the first period. After stopping charging the standard MLCC, the surge meter determines the holding voltage period of the standard MLCC, and the voltage values ​​of the standard MLCC at different time points during the voltage drop period after the holding voltage period. A standard waveform is obtained based on the voltage values ​​at different time points during the charging period, the holding voltage period, and the voltage drop period. The first voltage is the maximum voltage that the standard MLCC can withstand, the standard MLCC is an MLCC that meets the withstand voltage requirements, and the specifications of the standard MLCC are the same as those of the MLCC under test.

[0081] Among them, the waveform reference of standard MLCC Figure 3For the waveform 302 in [reference], the first voltage is usually three times the working voltage of the MLCC, which is also the maximum voltage that the MLCC can withstand. The specifications of the MLCC generally refer to the same capacitance value, that is, the MLCC under test and the standard MLCC have the same capacitance value of the same specification.

[0082] In an embodiment of the present application, the surge meter compares the test waveform with the standard waveform to obtain information reflecting the voltage withstand of the sample under test, including: when the surge meter determines that the error between the test waveform and the standard waveform is within the preset range, it determines that the voltage withstand of the MLCC under test is qualified. When the surge meter determines that the error between the test waveform and the standard waveform is outside the preset range, it determines that the voltage withstand is unqualified.

[0083] As an example, after the surge meter charges the MLCC sample under test with the first voltage, the voltage of the MLCC under test reaches the second voltage. Due to some differences in different MLCCs, even if the voltage withstand of the MLCC is qualified, there may still be a difference between the second voltage and the first voltage, so preset conditions are set. Figure 4 The difference between the voltage during the voltage holding period of the dashed horizontal line in [reference] and the standard waveform is the preset condition. When the difference between the first voltage and the second voltage is lower than or equal to the preset condition, the voltage withstand of the MLCC sample under test can be regarded as qualified, as shown in Figure 4 (a) in [reference]. When the difference between the first voltage and the second voltage is higher than the preset condition, the voltage withstand of the MLCC sample under test is unqualified, as shown in Figure 4 (b) in [reference].

[0084] In an embodiment of the present application, the MLCC tester has a display device. When it is determined that the voltage withstand of the MLCC under test is qualified, the display device displays information indicating that the voltage withstand of the MLCC under test is qualified. When it is determined that the voltage withstand of the MLCC under test is unqualified, the display device displays information indicating that the voltage withstand of the MLCC under test is unqualified.

[0085] In an embodiment of the present application, the display device is connected to the MLCC tester, and displays the test waveform 501 of the MLCC under test and the standard waveform 502 of the standard MLCC by the surge meter, as shown in Figure 5 [reference], where the prompt information 503 is shown in the upper right corner of the display device. Figure 5 In (a) of [reference], when the waveform 501 is the same as the waveform 502, the prompt information �03 is displayed as the first information "OK", indicating that the voltage withstand of the MLCC sample under test is qualified. Figure 5 In (b) of [reference], when the waveform 501 is different from the waveform 502, the prompt information 503 is displayed as the second information "NG", indicating that the voltage withstand of the MLCC sample under test is unqualified.

[0086] In one embodiment of the present application, the MLCC testing machine further has one or more testing instruments, and one or more of the testing instruments are connected to the control device to determine the indication information of whether the first performance parameter of the MLCC to be tested is qualified. Different testing instruments measure different performance parameters, and the first performance parameter is a performance parameter of the MLCC to be tested other than the withstand voltage. According to the information indicating whether the withstand voltage of the MLCC to be tested reflected by the surge instrument and the indication information of whether the first performance parameter of the MLCC to be tested by one or more testing instruments is qualified, the control device transfers the MLCC to be tested to the corresponding sorting and collecting box.

[0087] As an example, as Figure 6 shown, the MLCC testing machine has a testing instrument. The testing instrument 602 and the surge instrument 603 are connected to the processor 601 in the control device, and the determination actuator 604 is connected to the processor 601. The surge instrument 603 is a customized instrument for testing the withstand voltage of the MLCC, and the testing instrument 602 is a capacitance instrument for testing the capacitance of the MLCC. After the customized instrument tests the MLCC to be tested, it sends the tested withstand voltage result to the processor 601. After the capacitance instrument tests the MLCC to be tested, it sends the tested capacitance result to the processor 601. The processor 601 controls the determination actuator 604 to transfer the MLCC to be tested to the corresponding sorting and collecting box 605 according to the capacitance size and the qualification of the withstand voltage.

[0088] In one embodiment of the present application, the MLCC testing machine is also connected to a moving device for driving the capacitor to move. The method provided by the embodiment of the present application further includes: the control device controls the moving device to sequentially pass through the test positions of each testing instrument and the surge instrument.

[0089] The structure of the moving device can refer to the description in the prior art and will not be elaborated here. Any device that can drive the capacitor to move can be regarded as the moving device of the present application.

[0090] In a possible implementation manner, the moving device for driving the capacitor to move includes a loading tray for placing the MLCC to be tested and a conveyor belt matching the MLCC testing machine.

[0091] As an example, as Figure 7As shown, one or more testing instruments include the following: capacitance meter 702, first insulation meter 703, and second insulation meter 704. The capacitance meter 702 is used to test the capacitance of the MLCC under test. The first MLCC sample under test moves sequentially, being tested at the corresponding stations of capacitance meter 702, first insulation meter 703, second insulation meter 704, and surge meter 705. After each instrument completes its test, the result is sent to processor 701 for processing. Processor 701 controls the judgment execution mechanism 706 to transfer the MLCC sample under test to the corresponding sorting and receiving box 707 based on the test results of all instruments.

[0092] This application provides an MLCC testing machine, including a surge meter and a control device connected to the surge meter. The control device sends a test command to the surge meter when it detects that the MLCC under test is in the test position of the surge meter. The test command is used to detect the voltage change of the MLCC under test within a preset time period. The surge meter measures the voltage change of the MLCC under test within the preset time period according to the test command, and provides information reflecting the withstand voltage of the MLCC under test to the control device based on the voltage change of the MLCC under test within the preset time period. The control device is also used to determine whether the withstand voltage of the MLCC under test is qualified based on the information.

[0093] Optionally, the MLCC testing machine further includes: one or more testing instruments, which are connected to the control device. The control device is also used to determine, through the one or more testing instruments, whether a first performance parameter of the MLCC under test is qualified, wherein different testing instruments measure different performance parameters, and the first performance parameter is a performance parameter of the MLCC under test other than the withstand voltage.

[0094] The control device is also used to transfer the MLCC under test to the corresponding sorting and receiving box based on the information from the surge meter reflecting whether the withstand voltage of the MLCC under test is qualified, and the indication information from one or more of the test meters indicating whether the first performance parameter of the MLCC under test is qualified.

[0095] In the above embodiments, the descriptions of each embodiment have different focuses. For parts that are not described in detail or recorded in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0096] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0097] The above-described embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. A method of testing the voltage resistance of an MLCC, characterized by, The method is applied to an MLCC testing machine with a surge instrument and a control device, and the method comprises: When a to-be-tested MLCC is located at a test position of the surge instrument and the surge instrument is connected with the to-be-tested MLCC, the control device controls the surge instrument to detect a first voltage variation condition and a second voltage variation condition of the to-be-tested MLCC, The first voltage variation condition is used to reflect a variation of a voltage of the to-be-tested MLCC from an initial value to a target voltage value in a charging process of the to-be-tested MLCC, and the second voltage variation condition is used to reflect a variation of the voltage of the to-be-tested MLCC in a first time period from a time when the charging ends to a time when the voltage of the to-be-tested MLCC decreases from the target voltage value to a preset value; The surge instrument obtains a test waveform of the to-be-tested MLCC according to the first voltage variation condition and the second voltage variation condition, and the test waveform is used to reflect a rule of a variation of the voltage of the to-be-tested MLCC with time in a charging time period, a voltage-maintaining time period and a voltage-falling-back time period; The surge instrument compares the test waveform with a standard waveform to obtain information used to reflect a voltage resistance of the to-be-tested MLCC, and the standard waveform is used to reflect a rule of a variation of a voltage of a standard MLCC with time in the charging time period, the voltage-maintaining time period and the voltage-falling-back time period; The control device determines whether the voltage resistance of the to-be-tested MLCC is qualified according to the information used to reflect the voltage resistance of the to-be-tested MLCC.

2. The method of claim 1, wherein, The control device controls the surge instrument to detect the first voltage variation condition and the second voltage variation condition of the to-be-tested MLCC, and the control device comprises: The control device sends a start testing instruction to the surge instrument; The surge instrument charges the to-be-tested MLCC with a specified charging voltage in a charging time period in response to the start testing instruction, and collects voltage values of the to-be-tested MLCC at different time points in the charging time period to obtain the first voltage variation condition; The surge instrument collects the voltage values of the to-be-tested MLCC at different time points in a first time period to obtain the second voltage variation condition, The first time period comprises a voltage-maintaining time period of the to-be-tested MLCC and a time period in which the voltage of the to-be-tested MLCC decreases from the target voltage value to a preset value, and a starting time point of the first time period is the time when the charging ends.

3. The method of claim 2, wherein, Before the control device sends the start testing instruction to the surge instrument, the method further comprises: The control device provides charging parameters for charging the to-be-tested MLCC to the surge instrument according to an input operation of a user, and the charging parameters comprise the specified charging voltage of the surge instrument for charging the to-be-tested MLCC and information used to determine the charging time period.

4. The method of claim 1, wherein, Before detecting the voltage resistance of the to-be-tested MLCC, the method comprises: The surge instrument charges the standard MLCC with a first voltage in a charging time period, and records voltage values of the standard MLCC at different time points in the charging time period; The surge instrument determines a voltage value of the standard MLCC at different time points in a voltage falling period after a pressure maintaining period of the standard MLCC, from a charging end time point of the standard MLCC; The standard waveform is obtained according to the voltage values at different time points in the charging period, the pressure maintaining period and the voltage falling period; The first voltage is a maximum voltage that can be borne by the standard MLCC, The standard MLCC is an MLCC with required pressure resistance, and the standard MLCC has the same specification as the to-be-tested MLCC.

5. The method of claim 1, wherein, The surge instrument compares the test waveform with the standard waveform to obtain information reflecting pressure resistance of the to-be-tested sample, including: When the surge instrument determines that an error between the test waveform and the standard waveform is within a preset range, it is determined that the pressure resistance of the to-be-tested MLCC is qualified; When the surge instrument determines that the error between the test waveform and the standard waveform is outside the preset range, it is determined that the pressure resistance is unqualified.

6. The method according to any one of claims 1 to 5, characterized in that, The MLCC testing machine has a display device, When it is determined that the pressure resistance of the to-be-tested MLCC is qualified, the display device displays information indicating that the pressure resistance of the to-be-tested MLCC is qualified; When it is determined that the pressure resistance of the to-be-tested MLCC is unqualified, the display device displays information indicating that the pressure resistance of the to-be-tested MLCC is unqualified.

7. The method according to any one of claims 1 to 5, characterized in that, The MLCC testing machine further has one or more test instruments, and the control device is connected to the one or more test instruments, and the method further includes: The control device determines, through the one or more test instruments, indication information of whether a first performance parameter of the to-be-tested MLCC is qualified, different test instruments measure different performance parameters, and the first performance parameter is a performance parameter of the to-be-tested MLCC other than the pressure resistance; The control device determines, according to the information reflecting whether the pressure resistance of the to-be-tested MLCC is qualified and the indication information of whether the first performance parameter of the to-be-tested MLCC is qualified, the control device transfers the to-be-tested MLCC to a corresponding classification receiving box.

8. The method of claim 7, wherein, The MLCC testing machine is further connected to a moving device for moving the to-be-tested MLCC, and the method further includes: The control device determines test positions of each of the test instruments and the surge instrument; According to the test positions of each of the test instruments and the surge instrument, a detection sequence is determined; The control device controls the moving device to sequentially pass through the test positions of each of the test instruments and the surge instrument according to the detection sequence.

9. An MLCC tester characterized by, The MLCC testing machine includes a surge instrument and a control device connected to the surge instrument, The control device is configured to send a test instruction to the surge instrument when it is detected that the to-be-tested MLCC is located at a test position of the surge instrument and the surge instrument is connected to the to-be-tested MLCC, the test instruction being used to detect a first voltage variation condition and a second voltage variation condition of the to-be-tested MLCC, The first voltage variation condition is used to reflect a variation of the voltage of the to-be-tested MLCC from an initial value to a target voltage value in a charging process of the to-be-tested MLCC, and the second voltage variation condition is used to reflect a variation of the voltage of the to-be-tested MLCC in a first time period from a time when the charging ends to a time when the voltage decreases from the target voltage value to a preset value. The surge instrument is configured to obtain a test waveform of the to-be-tested MLCC according to the first voltage variation condition and the second voltage variation condition, the test waveform being used to reflect a rule of a variation of the voltage of the to-be-tested MLCC with time in a charging time period, a voltage-maintaining time period and a voltage-falling-back time period. The surge instrument is further configured to compare the test waveform with a standard waveform to obtain information used to reflect a voltage resistance of the to-be-tested MLCC, the standard waveform being used to reflect a rule of a variation of a voltage of a standard MLCC with time in the charging time period, the voltage-maintaining time period and the voltage-falling-back time period. The control device is further configured to determine whether the voltage resistance of the to-be-tested MLCC is qualified according to the information used to reflect the voltage resistance of the to-be-tested MLCC.

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