Power device online test system and power device test control method

Abstract

The invention relates to a power device online test system and a power device test control method. The system comprises an upper computer, a test board and a digital signal generator, the test board and the digital signal generator are connected with the upper computer, n aging circuits, driving circuits and measuring circuits are integrated on the test board, and the upper computer is used for determining test parameters of periodic tests of at least one to-be-tested power device and determining the test parameters of the to-be-tested power device for each test. Determining a performance test type of the to-be-tested power device according to the test parameters, generating a performance test instruction corresponding to the performance test type, and sending the performance test instruction to a digital signal generator; generating a corresponding pulse test signal, and transmitting the pulse test signal to the driving circuit; a relay in a test channel is controlled to be switched on and / or switched off according to the pulse test signal, a performance test corresponding to the performance test type is achieved for the to-be-tested power device through the test channel, and the test channel comprises an aging circuit and a measuring circuit.

Description

Technical Field

[0001] The present application relates to the field of device testing technology, and in particular to a power device online testing system and a power device testing control method. Background Art

[0002] Power devices (e.g., GaN power devices) play a key role in various electronic devices and power systems, but their applications face many reliability issues, and power devices generally operate under high voltage, high power, and high temperature conditions. In order to ensure their practical application in complex environments, it is very important to study the reliability of the devices and the mechanism of failure. Among them, the current collapse effect has become the most critical issue in the use of power devices, resulting in an increase in dynamic on-resistance after switching from the high-voltage off state. At present, high temperature reverse bias (HTRB) and high temperature gate bias (HTGB) stress tests are often used to evaluate the degradation mechanism of GaN power devices.

[0003] In the related art, the test of power devices can only be controlled offline, resulting in low test efficiency and test reliability. Summary of the invention

[0004] Based on this, it is necessary to provide a power device online testing system and a power device testing control method that can improve the efficiency of power device testing and ensure test reliability in response to the above technical problems.

[0005] In a first aspect, the present application provides an online testing system for a power device, the system comprising a host computer, a test board connected to the host computer, and a digital signal generator, the test board integrating n aging circuits, each of which is connected to a drive circuit measurement circuit, the test board is provided with at least one power device to be tested, the test board is placed outside an aging device, the aging device is connected to the aging circuit, and is used to perform an aging test on the power device to be tested, and the measurement circuit is used to measure the dynamic on-resistance of the power device to be tested, wherein:

[0006] The host computer is used to determine the test parameters of the periodic test of at least one of the power devices to be tested, determine the performance test type of the power device to be tested according to the test parameters for each test, generate a performance test instruction corresponding to the performance test type, and send the performance test instruction to the digital signal generator; the performance test type includes an aging test and an on-resistance measurement;

[0007] The digital signal generator is used to generate a corresponding pulse test signal according to the performance test instruction, and transmit the pulse test signal to the driving circuit;

[0008] The driving circuit is used to control the closing and / or opening of the relay in the test channel according to the pulse test signal, and to implement a performance test corresponding to the performance test type on the power device to be tested through the test channel. The test channel includes the aging circuit and the measurement circuit.

[0009] In one embodiment, the test parameters include aging environment parameters and test conditions of the aging test, the aging environment parameters include at least aging temperature and voltage stress, and the test conditions include at least temperature application cycle, voltage stress application cycle, parameter collection cycle, on-resistance measurement and online collection of current and voltage.

[0010] Among them, the temperature application cycle and the voltage stress application cycle each include at least two preset time intervals, and the preset time interval is the time period for applying dynamic pulse voltage stress to the power device to be tested when performing a dynamic stress aging test. The dynamic on-resistance is tested in each of the preset time intervals, and the current and voltage are collected online during the application of temperature and voltage stress.

[0011] In one of the embodiments, the driving circuit is further used to control the relay in the test channel to turn on and / or off according to the first pulse signal corresponding to the aging test, turn on the aging circuit, keep the measurement circuit disconnected, and perform the aging test on the power device to be tested when the performance test type is an aging test;

[0012] In the case where the testable type is the on-resistance measurement, the relay in the test channel is controlled to be turned on and / or off according to a second pulse signal corresponding to the on-resistance measurement, the measurement circuit is turned on, the aging circuit is kept disconnected, and dynamic on-resistance measurement is performed on the power device to be tested.

[0013] In one embodiment, the power device to be tested is a GaN power device, and the host computer is further used to collect aging data of the power device to be tested and dynamic resistance data of the power device to be tested in each test, and determine the on-resistance of the power device to be tested according to the dynamic resistance data;

[0014] Among them, the aging data at least includes gate leakage current, drain voltage, drain leakage current, temperature and cumulative aging times; the dynamic resistance data includes, in the case of on-resistance measurement, the clamping point voltage value in the clamping circuit in the measurement circuit, the drain voltage value of the power device to be measured and the sampling resistance in the measurement circuit.

[0015] In one of the embodiments, the host computer is further used to perform device failure analysis on the power device to be tested according to the aging data and the on-resistance to obtain device failure analysis data.

[0016] In one of the embodiments, the host computer is further used to perform an aging test on the power device to be tested for each test, and collect current aging data of the current aging test;

[0017] If the current aging data does not exceed the preset device failure threshold or the calculated on-resistance does not exceed the preset on-resistance, a threshold voltage test instruction is generated, wherein the threshold voltage test instruction is used to instruct an external voltage source to apply voltage to the test board to perform a threshold voltage test and obtain the threshold voltage of the power device to be tested;

[0018] Performing an on-resistance test on the power device to be tested, obtaining and saving the current dynamic on-resistance of the power device to be tested;

[0019] If the number of test cycles in the current aging data is greater than the preset number, or the current on-resistance is greater than the preset dynamic on-resistance, or the threshold voltage is greater than the preset threshold voltage, the test of the power device to be tested is terminated.

[0020] In one of the embodiments, the digital signal generator is further used to generate a corresponding double-pulse test signal or a multi-pulse test signal according to the performance test instruction, and transmit the double-pulse test signal or the multi-pulse test signal to the driving circuit.

[0021] In one of the embodiments, the system further includes an oscilloscope, which is used to display electrical parameters of the power device under test during the test process.

[0022] In one of the embodiments, the host computer is further used to obtain a target image including the power device to be tested, identify the target image, determine the test type of the power device to be tested; and determine test parameters matching the test type from preset test parameters.

[0023] In a second aspect, the present application further provides a control method for power device testing, which is applied to any of the above-mentioned systems, and the method includes:

[0024] Determine a test parameter for a periodic test of at least one of the power devices to be tested, determine a performance test type of the power device to be tested according to the test parameter for each test, and generate a performance test instruction corresponding to the performance test type; the performance test type includes an aging test and an on-resistance measurement;

[0025] The performance test instruction is sent to the digital signal generator to instruct the digital signal generator to generate a corresponding pulse test signal according to the performance test instruction, and the pulse test signal is transmitted to the drive circuit so that the drive circuit controls the relay in the test channel to close and / or open according to the pulse test signal, and a performance test corresponding to the performance test type is performed on the power device to be tested through the test channel, and the test channel includes the aging circuit and the measurement circuit.

[0026] The above-mentioned power device online testing system and power device testing control method determine the test parameters of at least one power device to be tested by a host computer, wherein the power device to be tested is arranged on a test board, and the host computer determines the performance test type of each power device to be tested according to the test parameters. Based on this test board, at least one power device to be tested can be tested and controlled at the same time. After completing the aging test, the test instructions for measuring the on-resistance of each power device to be tested can be directly output according to the test parameters to realize the on-resistance measurement. There is no need to move the power device to be tested to measure the on-resistance. In addition, by connecting the host computer, the power device to be tested and the test board, the test control of the power device to be tested can be directly realized online, thereby improving the test efficiency and ensuring the reliability of the test. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions in the embodiments of the present application or related technologies, the drawings required for use in the embodiments of the present application or related technical descriptions will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0028] Figure 1 A structural block diagram of an online testing system for a power device in one embodiment;

[0029] Figure 2 A schematic diagram of the structure of a test board in one embodiment;

[0030] Figure 3 A flowchart of mode switching and dynamic detection in one embodiment;

[0031] Figure 4 A structural block diagram of an online testing system for a power device in another embodiment;

[0032] Figure 5 A schematic diagram of ports on a test board in one embodiment;

[0033] Figure 6A schematic diagram of performing a stress test on a power device to be tested under high temperature conditions in an embodiment;

[0034] Figure 7 is dynamic on-resistance measurement data of a power device to be tested in one embodiment;

[0035] Figure 8 is a control timing diagram of a relay in an aging mode in one embodiment;

[0036] Fig. 9 A schematic flow chart of a control method for testing a power device in one embodiment;

[0037] Fig.10 FIG. 4 is a diagram showing the internal structure of a computer device in one embodiment. DETAILED DESCRIPTION

[0038] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0039] It is understandable that during the aging process, leakage current and voltage are generally collected online. However, for collecting dynamic on-resistance, the usual practice is to remove the device from the aging module after a test cycle and then evaluate its dynamic on-resistance. Obviously, offline data collection will introduce inaccuracies in the test, and the related technology lacks a way to monitor and evaluate the degradation degree of GaN power devices online. Based on this, a power device online test system is proposed.

[0040] In an exemplary embodiment, Figure 1 As shown, a power device online test system is provided, the system includes a host computer, a test board connected to the host computer and a digital signal generator, the test board integrates n aging circuits, each aging circuit is connected to a drive circuit measurement circuit, the test board is provided with at least one power device to be tested, the test board is placed outside the aging device, the aging device is connected to the aging circuit, and is used to perform an aging test on the power device to be tested, and the measurement circuit is used to measure the dynamic on-resistance of the power device to be tested, wherein:

[0041] A host computer is used to determine test parameters for periodic testing of at least one power device to be tested. For each test, a performance test type of the power device to be tested is determined according to the test parameters, a performance test instruction corresponding to the performance test type is generated, and the performance test instruction is sent to a digital signal generator; the performance test type includes an aging test and an on-resistance measurement; the digital signal generator is used to generate a corresponding pulse test signal according to the performance test instruction, and transmit the pulse test signal to a drive circuit; the drive circuit is used to control the closing and / or opening of a relay in a test channel according to the pulse test signal, and a performance test corresponding to the performance test type is implemented on the power device to be tested through the test channel, and the test channel includes an aging circuit and a measurement circuit.

[0042] Among them, the power device to be tested can be but is not limited to a GaN device, including various types of GaN power devices, for example, p-GaN, cascode structure, etc. This embodiment is described by taking the power device to be tested as a GaN device as an example. The power device to be tested can be a test board with a patch on the plug-in, or it can be set on the test board by other means, which is not limited here. The power device to be tested is a GaN device, and the corresponding aging test can include a high-temperature gate dynamic aging test and a high-temperature drain dynamic aging test.

[0043] The aging device can be a device that can perform aging experiments such as HTRB, HTGB, PC, etc. The high-temperature equipment in the aging device is a heating table, oven and other equipment. The voltage device used to provide power to the system can be a DC stabilized voltage, an AC voltage source, etc. Among them, the high-temperature application mode includes at least one of a blast drying oven and high-temperature silicone oil configured on the heating plate. This high-temperature application mode creates a temperature field for the device under test (DUT), which can heat the device under test from room temperature to 180°C, ensuring uniform temperature distribution and eliminating the influence of humidity stress. At the same time, by optimizing the device placement method, the evaluation board is placed away from the high-temperature source to prevent components from aging during accelerated life tests.

[0044] A test cycle of the power device to be tested includes aging test and on-resistance measurement, and the test parameters of each test cycle are pre-set. During the entire aging process, the gate leakage current, drain leakage current, temperature, voltage of the device, and the shell temperature of the power device to be tested can be collected online in real time. In order to ensure the accuracy and repeatability of the test, the test board includes at least 3 or more channels. For example, a four-channel test system can also be used to test 3 devices, 2 devices or a single device, and the channel switching can be achieved by controlling the relay on the test channel.

[0045] The test board integrates n aging circuits, each aging circuit is connected to a drive circuit measurement circuit, and the test board is provided with at least one power device to be tested. Figure 2 As shown, a structural schematic diagram of a test board is provided, which can perform two aging tests, HTGB stress and HTRB stress, on the power device to be tested, n is 4, and the four driving circuits are Driver1, Driver2, Driver3 and Driver4, respectively, and Driver1, Driver2, Driver3 and Driver4 are respectively connected with PWM control1 (Pulse Width Modulation, pulse width modulation), PWMcontrol2, PWM control3 and PWM control4. The test board is also provided with a power module, which includes a power supply V_bus and a capacitor C2 connected in parallel with the power supply.

[0046] The power devices to be tested corresponding to each driving circuit are GaN power devices, namely DUT1, DUT2, DUT3 and DUT4. Some relays in the switch circuits of the aging circuit and the measurement circuit, for example, the common switch circuit of the aging circuit and the measurement circuit is The aging relays Relay1_3, Relay2_3, Relay3_3, Relay4_3 and Relay_HTRB connected by stress, the switching circuit in the first aging circuit includes 4 switching devices, namely relays Relay1_1, Relay1_2, Relay1_3 and Relay_HTRB, the switching circuit in the second aging circuit includes 4 switching devices, namely relays Relay2_1, Relay2_2, Relay2_3 and Relay_HTRB, the switching circuit in the third aging circuit includes 4 switching devices, namely relays Relay3_1, Relay3_2, Relay3_3 and Relay_HTRB, and the switching circuit in the fourth aging circuit includes 4 switching devices, namely relays Relay4_1, Relay4_2, Relay4_3 and Relay_HTRB.

[0047] The measurement circuit includes a load circuit and a clamp circuit. The load circuit includes a power device S1 and an inductor L1. The power device S1 and the inductor L1 are connected in parallel. One end of the parallel connection is electrically connected to the switching module, and the other end of the parallel connection is connected to the power module. The clamp circuit includes a first diode D1, a first resistor R1, a first capacitor C1 and a low-voltage DC power supply V. The anode of the first diode D1 is connected to one end of the first resistor R1, the cathode of the first diode D1 is connected to the module to be measured, and the first capacitor C1 is connected in parallel to the low-voltage DC power supply V. One end of the parallel connection is grounded, and the other end is electrically connected to the other end of the first resistor R1. Figure 2 As can be seen from the test board shown, it can be seen that the circuit includes multiple test channels, each test channel includes at least two half-bridge circuits of GaN devices, a gate drive circuit and a clamping circuit. Further, on the basis of the gate drive circuit and the clamping circuit included in the test board, the half-bridge circuit composed of GaN devices (e.g., including the power device to be tested and the power device S1) and the sampling resistor Isen can be called a hard switching test circuit, and the other parts of the circuit can be called a soft switching test circuit. It should be noted that the clamping circuit can be an active clamping circuit or a passive clamping circuit.

[0048] The control method of the upper computer for the aging test and on-resistance measurement of the power device to be tested can be, when it is determined that at least one power device to be tested needs to be tested, generating the corresponding performance test instructions according to the test parameters of each power device to be tested. Among them, the performance test instructions include aging test instructions and on-resistance measurement instructions. In the same test cycle, the aging tests of all the power devices to be tested can be executed at the same time, and the aging time of each power device to be tested can be equal or unequal. The on-resistance measurement instructions of all the power devices to be tested are not executed at the same time, and only the on-resistance measurement of one power device to be tested can be executed at a time. If after a certain aging of all the power devices to be tested is completed, the resistance measurement priority of the power devices to be tested after aging can be determined according to the order of the aging end time.

[0049] For example, when it is monitored that the power device to be tested needs to be aged, an aging test instruction for the aging test is generated, and the digital signal generator is controlled to generate a corresponding pulse signal according to the aging test instruction, which is output to a drive circuit matching the power device to be tested, and the relay in the test channel is controlled to be closed and / or disconnected, the aging circuit is turned on, and the aging device is controlled to meet the preset aging conditions according to the aging test instruction, and an aging test is performed on the power device to be tested. When it is monitored that the aging test is ended and the preset end conditions are not met, a mode switching instruction is generated to end the current aging test, switch to the on-resistance measurement mode, and measure the on-resistance of the power device to be tested.

[0050] It is understandable that the digital signal generator can provide a double pulse or multi-pulse test signal. Accordingly, the digital signal generator is also used to generate a corresponding double pulse test signal or a multi-pulse test signal according to the performance test instruction, and transmit the double pulse test signal or the multi-pulse test signal to the drive circuit.

[0051] The above-mentioned power device online test system determines the test parameters of at least one power device to be tested through a host computer, wherein the power device to be tested is arranged on a test board, and the host computer determines the performance test type of each power device to be tested according to the test parameters. Based on this test board, at least one power device to be tested can be tested and controlled at the same time. After completing the aging test, the test instructions for measuring the on-resistance of each power device to be tested can be directly output according to the test parameters to realize the on-resistance measurement, and the power device to be tested does not need to be moved for the on-resistance measurement. In addition, by connecting the host computer, the power device to be tested and the test board, the test control of the power device to be tested can be directly realized online, thereby improving the test efficiency and ensuring the reliability of the test.

[0052] In an exemplary embodiment, the test parameters of each test cycle include aging environment parameters and test conditions of the aging test, the aging environment parameters include at least aging temperature and voltage stress, and the test conditions include at least temperature application cycle, voltage stress application cycle, parameter acquisition cycle, on-resistance measurement, and online current and voltage acquisition.

[0053] Among them, the temperature application cycle and the voltage stress application cycle each include at least two preset time intervals, the preset time interval is the time period for applying dynamic pulse voltage stress to the power device to be tested during the dynamic stress aging test, each preset time interval tests the dynamic on-resistance, and the current and voltage are collected online during the temperature and voltage stress application. It can be understood that the test parameters of each test cycle can be set according to actual needs, that is, dynamically adjusted, for example, the test temperature (that is, ambient temperature), electrical stress (which may include voltage stress and current stress) and the preset time interval are dynamically set according to the device to be tested. Optionally, the electrical stress application cycle includes a gate stress application cycle and a drain stress application cycle.

[0054] In an exemplary embodiment, a working mode of the driving circuit in the above system is provided, including the following:

[0055] The driving circuit is further used for controlling the relay in the test channel to be turned on and / or off according to the first pulse signal corresponding to the aging test, turning on the aging circuit, keeping the measuring circuit disconnected, and performing the aging test on the power device to be tested when the performance test type is an aging test;

[0056] When the test type is on-resistance measurement, the relay in the test channel is controlled to be turned on and / or off according to the second pulse signal corresponding to the on-resistance measurement, the measurement circuit is turned on, the aging circuit is kept disconnected, and dynamic on-resistance measurement is performed on the power device to be tested.

[0057] For example, Figure 2 Taking the driving circuit Driver1 in the test board shown as an example, when the aging test of HTGB stress is performed on the power device DUT1 to be tested, the first pulse signal controls Relay1_2, Relay1_HTRB and Relay1_1 in the test channel to be disconnected, and Relay1_3 to be closed. If the aging test of HTRB stress is performed, Relay1_HTRB and Relay1_1 are closed, and Relay1_2 and Relay1_3 are disconnected. After the aging test is completed, the on-resistance measurement mode is entered. At this time, Relay1_2 and the corresponding Relay1_1 are closed, and all other relays are disconnected.

[0058] In the above method, the host computer generates aging test instructions and on-resistance measurement instructions, and drives the closing and opening of the relay in the test channel online to realize mode switching, thereby avoiding frequent movement of the resistance device to be tested during the test and simplifying the test operation.

[0059] In order to realize the analysis of the power device to be tested, it is necessary to determine the data used for the analysis. In an exemplary embodiment, the power device to be tested is a GaN power device, and the host computer is also used to collect the aging data of the power device to be tested and the dynamic resistance data of the power device to be tested in each test, and determine the on-resistance of the power device to be tested according to the dynamic resistance data;

[0060] Among them, the aging data at least includes gate leakage current, drain voltage, drain leakage current, temperature and cumulative aging times; the dynamic resistance data includes, in the case of on-resistance measurement, the clamp point voltage value in the clamp circuit in the measurement circuit, the drain voltage value of the power device to be tested and the sampling resistance in the measurement circuit. It should be noted that the dynamic on-resistance data in the online test includes double-pulse test data and multi-pulse test data. The dynamic on-resistance test includes the dynamic resistance data corresponding to the hard switch and the dynamic on-resistance data corresponding to the soft switch. The double pulse and multi-pulse here are test pulse settings, and the hard switch and soft switch are test circuit designs.

[0061] Exemplarily, when performing a high-temperature gate dynamic aging test on a GaN power device, the aging data obtained includes at least the gate leakage current, the device case temperature of the GaN power device, and the cumulative number of aging times. When performing a high-temperature drain dynamic aging test on a GaN power device, the aging data obtained includes the drain turn-on voltage, the drain turn-on current, the drain turn-off leakage current, the device case temperature of the GaN power device, and the cumulative number of aging times.

[0062] The on-resistance of the power device to be tested can be determined based on the dynamic resistance data: the voltage at both ends of the power device to be tested can be determined by subtracting the voltage at the clamping point from the voltage at the drain voltage of the power device to be tested (i.e., the voltage at both ends of the first diode D1), and the current can be obtained by dividing the voltage at both ends of the sampling resistor by the resistance value of the sampling resistor. Based on the voltage and current at both ends of the power device to be tested, the on-resistance of the GaN power device can be determined. This method of resistance calculation can avoid the influence of the measurement value of the dynamic on-resistance at the millivolt level and the voltage at the hundred-volt level when the device is turned off on the measurement accuracy, thereby ensuring the measurement accuracy.

[0063] It can be understood that the purpose of the above system is to analyze the power device to be tested and to more accurately evaluate the usage of the power device under working conditions.

[0064] In an exemplary embodiment, the host computer is further used to perform device failure analysis on the power device to be tested according to the aging data and the on-resistance to obtain device failure analysis data.

[0065] Among them, the aging data and on-resistance include multiple collections. Optionally, the host computer is also used to perform an aging test on the power device to be tested for each test, and collect the current aging data of the current aging test; if the current aging data does not exceed the preset device failure threshold or the calculated on-resistance does not exceed the preset on-resistance, a threshold voltage test instruction is generated, and the threshold voltage test instruction is used to instruct an external voltage source to apply voltage to the test board, perform a threshold voltage test, and obtain the threshold voltage of the power device to be tested; perform an on-resistance test on the power device to be tested, obtain the current on-resistance of the power device to be tested and save it; if the number of device test cycles in the current aging data is greater than the preset number, or the current dynamic on-resistance is greater than the preset dynamic on-resistance, or the threshold voltage is greater than the preset threshold voltage, then the test of the power device to be tested is terminated.

[0066] The on-resistance is the on-resistance calculated during the aging process, which can be determined based on Figure 2The circuit board shown sets a voltage sampling point at the drain of the device under test to obtain a first sampling voltage, and subtracts the voltage of the sampling resistor Isense from the first sampling voltage to obtain a voltage difference, which is calculated based on the voltage difference divided by the current flowing through the sampling resistor. This calculation method is different from the calculation method of the dynamic on-resistance.

[0067] In an exemplary embodiment, Figure 3 As shown, a flow chart of mode switching and dynamic detection is provided, the power device to be tested on the test board enters the aging mode, the upper computer collects the aging data of the power device to be tested online to calculate the on-resistance, and judges whether the aging data or the on-resistance exceeds the corresponding threshold value, if it exceeds, the current test is terminated, if it does not exceed, the threshold voltage test of the power device to be tested is performed, and the threshold voltage is saved. In order to ensure the reliability of the on-resistance measurement, it is often necessary to subtract the diode conduction voltage drop from the clamping point voltage measurement value and then subtract the error value of the system board, so it is necessary to calibrate the diode voltage drop and the system board error under different current and temperature conditions before the dynamic on-resistance can be calculated. Therefore, after the threshold voltage test, the dynamic on-resistance test error will be calibrated, and the error calibration process can be to control the power device to be tested to turn on, measure the clamping point voltage value and the drain voltage value (that is, the voltage across D1, the value will be different under different temperature and current conditions, normally as the temperature decreases, the current increases, and the diode voltage drop increases), and the difference between the measured clamping point voltage value and the drain voltage value will be used as a fixed value to calculate the on-resistance value. On this basis, a dynamic on-resistance test is performed and the data is saved. It is determined again if the number of device test cycles in the current aging data meets the requirements, such as being greater than the preset number or being within the preset value range, or the current dynamic on-resistance is greater than the preset dynamic on-resistance, or the threshold voltage is greater than the preset threshold voltage, then the test of the power device to be tested is terminated.

[0068] In an exemplary embodiment, the system further includes an oscilloscope, which is used to display the electrical parameters of the power device under test during the test process. Specifically, the oscilloscope can record the changes in information such as voltage and current of the power device under test in each test cycle over time, thereby helping engineers or technicians understand the characteristics of electronic signals. Information such as voltage and current includes but is not limited to data such as gate leakage current, drain voltage, and drain leakage current. The number of oscilloscopes can be two or more.

[0069] In an exemplary embodiment, Figure 4As shown, a power device online test system is provided, which includes the oscilloscope, a drive circuit, a digital signal generator, an auxiliary power supply, a high-voltage programmable DC power supply, an isolation transformer, a heating system (i.e., an aging device), a test board and a host computer, wherein the host computer is integrated with control acquisition and data processing software, as well as a temperature and data acquisition card. It is understandable that the drive circuit may be integrated on the test board or not integrated on the test board.

[0070] Among them, the auxiliary power supply is usually used to provide the required stable voltage and current for other components in the system. In the test system of GaN power devices, the auxiliary power supply may be used to drive electronic devices such as digital signal generators, control acquisition and data processing software to ensure that they can work properly. The role of the auxiliary power supply is to provide a stable power supply to ensure the reliability and stability of system components.

[0071] The high-voltage programmable DC power supply is used in the system to provide high-voltage DC power to apply voltage stress to the GaN power device and simulate the voltage environment under actual working conditions. The isolation transformer plays the role of electrical isolation in the system. It can isolate the high-voltage power supply from the control circuit to prevent electrical interference and potential safety risks.

[0072] The isolation transformer can also change the voltage level as needed to ensure that the GaN power device receives the appropriate voltage and current. The heating system can be called a heating table, which is used in the aging device to heat the power device under test. The load circuit can be regarded as a drive circuit.

[0073] based on Figure 2 The test board structure shown in the figure, in order to realize the mode conversion and online acquisition of the power device to be tested, the corresponding test board is provided with corresponding ports, such as Figure 5As shown, it includes acquisition ports and control ports. The red box represents the control port, and the blue box represents the acquisition port. The acquisition port includes the voltage and current acquisition ports during the aging process. For example, the signals acquired by the oscilloscope include the double pulse test V_sense acquisition X1, the double pulse test V_clamp acquisition X1, and the acquisition card signal acquisition includes the threshold voltage test Vgs acquisition X1, the threshold voltage test Id acquisition X1, the HTGB_Gate static current and voltage signal X4, the HTRB_Drain static current and voltage signal X4, the PC drain voltage signal X4, the thermocouple temperature acquisition, and the device shell temperature acquisition X8 of the power device to be tested. The control port includes the control signal port of the signal generator, the control port of the programmable voltage source, the port of the relay control signal and other control ports. The relay control signal port includes the drive relay control X4, the HTGB relay control X4 and the HTRB relay control X4. The signal generator includes a dual pulse control signal X1, the programmable voltage source port includes V_bus power supply voltage source (0-600v) X1, HTGB aging power supply (0-50v) X1, HTRB aging power supply (0-600v) X1, and other control ports include incubator temperature control X1.

[0074] It can be understood that the specific implementation amount of this embodiment can be achieved by the method recorded in any of the above embodiments, which will not be repeated here.

[0075] like Figure 6 As shown, two different bias test methods for performing stress testing on a power device to be tested under high temperature conditions in an exemplary embodiment are shown: a high temperature reverse bias stress test and a high temperature gate bias stress test.

[0076] Figure (a) High temperature reverse bias stress test, where the vertical axis (Y axis): source-drain voltage (Vds), in volts (V); horizontal axis (X axis): time (t), in hours (h). Test points: 1. Threshold voltage (Vth): the voltage at which the component starts to conduct; 2. Dynamic on-resistance: the resistance of the component when it is on at a specific voltage. Stress: During the test, a voltage higher than the normal operating voltage is applied to the component to simulate performance under extreme conditions. Aging temperature: The test is performed in a temperature range of 30°C to 150°C.

[0077] Figure (b) High temperature gate bias stress test: vertical axis (Y axis): gate-source voltage (Vgs), unit is volts (V); horizontal axis (X axis): time (t), unit is hours (h). Test points: 1. 1. Threshold voltage (Vth): the voltage at which the component starts to conduct; 2. Dynamic on-resistance: the resistance of the component when it is on at a specific voltage. Stress: During the test, a voltage is applied to the gate of the component to simulate performance under extreme conditions. Aging temperature: also carried out in the temperature range of 30℃ to 150℃.

[0078] Among them, the circuit symbols in the figure are: Vdstess: maximum source-drain voltage, Vg: gate-source voltage; S: source; G: gate; D: drain.

[0079] Based on the above system, performing a dynamic stress aging experiment on the GaN power device according to the aging mode and collecting electrical parameters of the tested GaN power device during the aging process may include:

[0080] Perform an initial test on the GaN power device, collect electrical parameters such as dynamic on-resistance and threshold voltage; place the GaN power device on a heating table, adjust the temperature to the required temperature, and apply gate bias; during the aging process, the host computer automatically records the gate leakage current online; after 24 hours of aging, control the relay and switch to the test mode to perform online tests on the dynamic on-resistance and threshold voltage; after the test is completed, switch to the aging mode again for aging, and record the gate leakage current online, and repeat this cycle. During the device aging process, monitor the changes in parameters such as dynamic on-resistance, threshold voltage, and leakage current online to explore the failure mechanism of the device. Based on this, the dynamic on-resistance measurement data of the power device to be tested is obtained, such as Figure 7 As shown, the horizontal axis of the graph represents time in nanoseconds (ns), and the vertical axis represents dynamic on-resistance in milliohms (mΩ). In the first few hundred nanoseconds after the test, the dynamic on-resistance has large fluctuations. This may be due to the transient response of the component when the stress is first applied, or the stabilization process of the test equipment in the initial stage. After about 500 nanoseconds, the fluctuation of the dynamic on-resistance begins to decrease and enters a relatively stable fluctuation range. This shows that the on-resistance of the component tends to stabilize after the initial transient response. From 500 nanoseconds to 2000 nanoseconds, the dynamic on-resistance remains at a relatively stable level, although there are still some small fluctuations. This shows that under long-term stress, the on-resistance of the component does not change much, showing good stability.

[0081] It is understandable that in the aging mode, the corresponding relay will be turned off to prevent electrical stress from being applied to the test circuit. The aging program is set through the host computer, and experiments such as HTRB, HTGB, and power cycling are performed. Another mode is the test, acquisition, and processing mode of dynamic on-resistance. Through the integrated design of the test module and the aging module, the device can be fully automatically aged in high temperature, high voltage and other environments, and the dynamic on-resistance can be fully automatically acquired online. The safety threshold can be set through the software, and the experiment will stop automatically when the parameter reaches the set value. During the entire aging process, the gate leakage current, drain leakage current, and temperature of the device can be collected online in real time. During the entire test process, the device remains stationary, preventing the inaccuracy of parameter acquisition caused by artificial movement of the device.

[0082] Furthermore, when there are a large number of power devices to be tested, in order to avoid manually inputting the test parameters of each power device to be tested one by one, the parameters of the power devices to be tested can be set in batches in the following manner.

[0083] In an exemplary embodiment, the host computer is further used to obtain a target image including the power device to be tested, identify the target image, determine the test type of the power device to be tested, and determine the test parameters matching the test type from the preset test parameters. The identification of the target image can be achieved by existing technology, which will not be described in detail here.

[0084] Based on any of the above embodiments, in an exemplary embodiment, a plurality of test channels are integrated on the test board, and different channels need to be turned on alternately through relay control, and at most one channel is turned on at any time. The cycle time and the duty cycle of the opening time of each channel are determined according to the aging requirements, and t1, t2, t3, and t4 can be set to be the same or different, and the total duty cycle does not exceed 100%. Figure 8 As shown in FIG. 1 , a control timing diagram of a relay in an aging mode is provided. This aging mode is different from HTGB and HTRB. It is a power cycle aging mode. The relay here is as follows Figure 2 RlayX_1 and RlayX_1 shown in , X represents the test channel, X is 1, 2, 3...n. The horizontal axis is the test cycle, and the vertical axis is the relay opening voltage. Taking the number of test channels X as 4, at each moment in the first cycle, only one channel among the four channels is opened, only channel 1 is opened at t1, only channel 2 is opened at t2, only channel 3 is opened at t3, and only channel 4 is opened at t4. Based on the same inventive concept, the embodiment of the present application also provides a control method for implementing the power device test of the power device online test system involved above. The implementation scheme for solving the problem provided by the method is similar to the implementation scheme recorded in the above system, so the specific limitations in the control method embodiments of one or more power device tests provided below can refer to the limitations of the power device online test system method above, and will not be repeated here.

[0085] In an exemplary embodiment, Fig. 9 As shown, a control method for power device testing is provided, which is described by applying the method to a system in any of the above embodiments, and includes the following steps 902 to 904. Among them:

[0086] Step 902, determine the test parameters of the periodic test of at least one power device to be tested, determine the performance test type of the power device to be tested according to the test parameters for each test, and generate a performance test instruction corresponding to the performance test type; the performance test type includes aging test and on-resistance measurement.

[0087] Step 904, sending the performance test instruction to the digital signal generator, instructing the digital signal generator to generate a corresponding pulse test signal according to the performance test instruction, transmitting the pulse test signal to the drive circuit, so that the drive circuit controls the relay in the test channel to close and / or open according to the pulse test signal, and performing a performance test corresponding to the performance test type on the power device to be tested through the test channel, and the test channel includes an aging circuit and a measurement circuit.

[0088] It should be noted that the specific implementation method can be achieved through the method described in the above embodiment, which will not be described in detail here.

[0089] The control method for power device testing described above determines the test parameters of at least one power device to be tested by a host computer, wherein the power device to be tested is arranged on a test board, and the host computer determines the performance test type of each power device to be tested according to the test parameters. Based on this test board, at least one power device to be tested can be tested and controlled simultaneously, and after the aging test is completed, the test instructions for measuring the on-resistance of each power device to be tested can be directly output according to the test parameters to realize the on-resistance measurement, and the power device to be tested does not need to be moved for the on-resistance measurement. In addition, by connecting the host computer, the power device to be tested and the test board, the test control of the power device to be tested can be directly realized online, thereby improving the test efficiency and ensuring the reliability of the test.

[0090] It should be understood that, although the various steps in the flowcharts involved in the above-mentioned embodiments are displayed in sequence according to the indication of the arrows, these steps are not necessarily executed in sequence according to the order indicated by the arrows. Unless there is a clear explanation in this article, the execution of these steps does not have a strict order restriction, and these steps can be executed in other orders. Moreover, at least a part of the steps in the flowcharts involved in the above-mentioned embodiments can include multiple steps or multiple stages, and these steps or stages are not necessarily executed at the same time, but can be executed at different times, and the execution order of these steps or stages is not necessarily to be carried out in sequence, but can be executed in turn or alternately with other steps or at least a part of the steps or stages in other steps.

[0091] Each module in the above-mentioned power device online test system can be implemented in whole or in part by software, hardware and their combination. Each of the above-mentioned modules can be embedded in or independent of the processor in the computer device in the form of hardware, or can be stored in the memory in the computer device in the form of software, so that the processor can call and execute the corresponding operations of each of the above modules.

[0092] In an exemplary embodiment, a computer device is provided. The computer device may be a terminal, and its internal structure diagram may be as shown in FIG. Fig.10 As shown. The computer device includes a processor, a memory, an input / output interface, a communication interface, a display unit and an input device. The processor, the memory and the input / output interface are connected through a system bus, and the communication interface, the display unit and the input device are connected to the system bus through the input / output interface. The processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The input / output interface of the computer device is used to exchange information between the processor and an external device. The communication interface of the computer device is used to communicate with an external terminal in a wired or wireless manner, and the wireless manner can be implemented through WIFI, a mobile cellular network, near field communication (Near Field Communication, NFC) or other technologies. When the computer program is executed by the processor, a control method for power device testing is implemented. The display unit of the computer device is used to form a visually visible picture, which can be a display screen, a projection device or a virtual reality imaging device. The display screen can be a liquid crystal display screen or an electronic ink display screen, and the input device of the computer device can be a touch layer covering the display screen, or a button, trackball or touchpad set on the computer device shell, or an external keyboard, touchpad or mouse.

[0093] Those skilled in the art will understand that Fig.10 The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application is applied. The specific computer device may include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.

[0094] In one embodiment, a computer device is further provided, including a memory and a processor, wherein a computer program is stored in the memory, and the processor implements the steps in the above-mentioned method embodiments when executing the computer program.

[0095] In one embodiment, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the steps in the above-mentioned method embodiments are implemented.

[0096] In one embodiment, a computer program product is provided, including a computer program, which implements the steps in the above method embodiments when executed by a processor.

[0097] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, stored data, displayed data, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, use and processing of relevant data must comply with relevant regulations.

[0098] Those of ordinary skill in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to the memory, database or other medium used in the embodiments provided in the present application can include at least one of non-volatile memory and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. As an illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM). The database involved in each embodiment provided in this application may include at least one of a relational database and a non-relational database. Non-relational databases may include distributed databases based on blockchains, etc., but are not limited to this. The processor involved in each embodiment provided in this application may be a general-purpose processor, a central processing unit, a graphics processor, a digital signal processor, a programmable logic device, a data processing logic device based on quantum computing, an artificial intelligence (AI) processor, etc., but are not limited to this.

[0099] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this application.

[0100] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. A power device online testing system, characterized in that: The system includes a host computer, a test board connected to the host computer, and a digital signal generator. The test board integrates n aging circuits, a drive circuit, and a measurement circuit. Each aging circuit is connected to a drive circuit. The test board is provided with at least one power device to be tested. The test board is placed outside the aging device. The aging device is connected to the aging circuit and is used to perform an aging test on the power device to be tested. The measurement circuit is used to measure the dynamic on-resistance of the power device to be tested, wherein: The host computer is used to determine the test parameters of the periodic test of at least one of the power devices to be tested, determine the performance test type of the power device to be tested according to the test parameters for each test, generate a performance test instruction corresponding to the performance test type, and send the performance test instruction to the digital signal generator; the performance test type includes an aging test and an on-resistance measurement; The digital signal generator is used to generate a corresponding pulse test signal according to the performance test instruction, and transmit the pulse test signal to the driving circuit; The driving circuit is used to control the closing and / or opening of the relay in the test channel according to the pulse test signal, and to implement a performance test corresponding to the performance test type on the power device to be tested through the test channel. The test channel includes the aging circuit and the measurement circuit.

2. The system according to claim 1, characterized in that The test parameters include aging environment parameters and test conditions of the aging test, the aging environment parameters include at least aging temperature and voltage stress, and the test conditions include at least temperature application cycle, voltage stress application cycle, parameter collection cycle, on-resistance measurement and online collection of current and voltage, Among them, the temperature application cycle and the voltage stress application cycle each include at least two preset time intervals, and the preset time interval is the time period for applying dynamic pulse voltage stress to the power device to be tested when performing a dynamic stress aging test. The dynamic on-resistance is tested in each of the preset time intervals, and the current and voltage are collected online during the application of temperature and voltage stress.

3. The system according to claim 2, characterized in that The driving circuit is further used for controlling the relay in the test channel to be turned on and / or off according to the first pulse signal corresponding to the aging test, turning on the aging circuit, keeping the measuring circuit disconnected, and performing the aging test on the power device to be tested when the performance test type is an aging test; In the case where the testable type is the on-resistance measurement, the relay in the test channel is controlled to be turned on and / or off according to a second pulse signal corresponding to the on-resistance measurement, the measurement circuit is turned on, the aging circuit is kept disconnected, and dynamic on-resistance measurement is performed on the power device to be tested.

4. The system according to any one of claims 1 to 3, characterized in that: The power device to be tested is a GaN power device, and the host computer is further used to collect aging data of the power device to be tested and dynamic resistance data of the power device to be tested in each test, and determine the on-resistance of the power device to be tested according to the dynamic resistance data; Among them, the aging data at least includes gate leakage current, drain voltage, drain leakage current, temperature and cumulative aging times; the dynamic resistance data includes, in the case of on-resistance measurement, the clamping point voltage value in the clamping circuit in the measurement circuit, the drain voltage value of the power device to be measured and the sampling resistance in the measurement circuit.

5. The system according to claim 4, characterized in that The host computer is also used to perform device failure analysis on the power device to be tested according to the aging data and the on-resistance to obtain device failure analysis data.

6. The system according to claim 5, characterized in that The host computer is also used to perform an aging test on the power device to be tested for each test and collect current aging data of the current aging test; If the current aging data does not exceed the preset device failure threshold or the calculated on-resistance does not exceed the preset on-resistance, a threshold voltage test instruction is generated, wherein the threshold voltage test instruction is used to instruct an external voltage source to apply voltage to the test board to perform a threshold voltage test and obtain the threshold voltage of the power device to be tested; Performing an on-resistance test on the power device to be tested, obtaining and saving the current dynamic on-resistance of the power device to be tested; If the number of test cycles in the current aging data is greater than the preset number, or the current dynamic on-resistance is greater than the preset dynamic on-resistance, or the threshold voltage is greater than the preset threshold voltage, the test of the power device to be tested is terminated.

7. The system according to claim 1, characterized in that The digital signal generator is further used to generate a corresponding double-pulse test signal or a multi-pulse test signal according to the performance test instruction, and transmit the double-pulse test signal or the multi-pulse test signal to the drive circuit.

8. The system according to claim 1, characterized in that The system further comprises an oscilloscope, which is used to display the electrical parameters of the power device to be tested during the test process.

9. The system according to claim 1, characterized in that The host computer is also used to obtain a target image including the power device to be tested, identify the target image, determine the test type of the power device to be tested; and determine test parameters matching the test type from preset test parameters.

10. A control method for power device testing, characterized in that: Applied to the system according to any one of claims 1 to 9, the method comprises: Determine a test parameter for a periodic test of at least one of the power devices to be tested, determine a performance test type of the power device to be tested according to the test parameter for each test, and generate a performance test instruction corresponding to the performance test type; the performance test type includes an aging test and an on-resistance measurement; The performance test instruction is sent to the digital signal generator to instruct the digital signal generator to generate a corresponding pulse test signal according to the performance test instruction, and the pulse test signal is transmitted to the drive circuit so that the drive circuit controls the relay in the test channel to close and / or open according to the pulse test signal, and a performance test corresponding to the performance test type is performed on the power device to be tested through the test channel, and the test channel includes the aging circuit and the measurement circuit.

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