A high-voltage, high-current high-end suspension driver circuit test method

Abstract

The present invention belongs to the technical field of integrated circuit testing, and specifically is a method for testing a high-voltage, high-current, high-end suspended driver circuit. The square wave generated by the digital channel of the tester is enhanced by an N-channel MOSFET tube as a logic input signal for the driver circuit; the high-end power supply terminal of the driver circuit and the floating source H terminal are connected in series, the floating source L terminal is connected to the H terminal of the high-voltage source of the tester, and the H terminal of the high-voltage source of the tester is connected to the high-end suspended offset voltage terminal of the driver circuit, thereby realizing high-voltage power supply and further testing all parameters of the driver circuit. The present invention only requires the production of a test circuit board to complete the testing needs of the entire circuit, saving testing costs.

Description

Technical Field

[0001] The invention belongs to the technical field of integrated circuit testing, in particular to a method for testing a high-voltage, high-current, high-end suspension driver circuit. Background Art

[0002] In power conversion devices, depending on the structure of the main circuit, the power switching devices generally adopt two methods: direct drive and isolation drive. Isolation drive is divided into electromagnetic isolation and optoelectronic isolation. Optoelectronic isolation has the disadvantages of poor common-mode suppression and slow transmission speed. Electromagnetic isolation uses pulse transformers as isolation components, which have fast response and strong anti-interference ability. However, the maximum transmission width of the signal is limited by the magnetic saturation characteristics, so the top of the signal is not easy to transmit. The driver circuit takes into account the advantages of optocoupler isolation and electromagnetic isolation, and is the first choice for small and medium-sized power conversion devices.

[0003] The driver's test conditions of high voltage, high current, and high input signal level have always been the key factors limiting the driver circuit test. The test efficiency is low and the test result stability is poor when assembling test equipment such as power supply, signal source, and oscilloscope together. However, using the test system as a platform and the system platform's technical indicators as the premise, the test conditions are converted by using peripheral components to meet the test requirements, thereby achieving full parameter testing, taking into account the stability and accuracy of the test results, and improving test efficiency. This is a better solution for driver circuit testing. Summary of the Invention

[0004] The purpose of the present invention is to provide a test method for a high-voltage, high-current suspension driver circuit, which can realize full-parameter testing of the circuit and make up for the defect of insufficient driving capability of the integrated circuit test system.

[0005] The technical solution adopted by the present invention to achieve the above-mentioned purpose is:

[0006] A high-voltage and high-current high-end suspension driver circuit test system comprises an N-channel MOSFET tube, a driver circuit, multiple resistors, and multiple relays, wherein: the gate of the N-channel MOSFET tube is connected to a digital channel of a test machine through a resistor R1, the drain of the N-channel MOSFET tube is respectively connected to a logic input terminal IN of the driver circuit and to a common power supply terminal FOVI-0 of the test machine through a resistor R2, the high-end power supply terminal VB of the driver circuit is connected to the H-end of a floating power supply FPVI-0 of the test machine, the high-end suspension offset voltage terminal VS of the driver circuit is connected to the H-end of a high-voltage source HVIK of the test machine through a relay K3, the H-end of the floating power supply FPVI-0 of the test machine is connected to the H-end of the high-voltage source HVIK of the test machine through relays K2 and K3 in sequence, and the L-end of the floating power supply FPVI-0 of the test machine is connected to the H-end of the high-voltage source HVIK of the test machine through relay K1.

[0007] A high-voltage and high-current high-end suspension driver circuit testing method comprises the following steps: inputting a square wave output by a tester into the driver circuit via an N-channel MOSFET; connecting the driver circuit's high-end power supply terminal VB, the high-end suspension offset voltage terminal VS, the tester's floating power supply FPVI-0, and the tester's high-voltage source HVIK via different relays; and controlling the on and off of different relays to respectively test the driver circuit's AC parameters, high-voltage leakage parameters, and short-circuit pulse current.

[0008] Test the AC parameters of the driver circuit, specifically:

[0009] Set the voltage threshold A of the logic input terminal IN and the voltage threshold B of the output terminal of the driver circuit. When the voltage value of the logic input terminal IN reaches threshold A, the time at this time is used as reference time 1. When the voltage value of the output terminal reaches threshold B, the time at this time is used as reference time 2. The difference between reference time 2 and reference time 1 is the AC parameter to be tested.

[0010] Test the high voltage leakage parameters of the driver circuit, specifically:

[0011] By controlling relay K2, the high-end power supply terminal VB and the high-end floating offset voltage terminal VS are short-circuited through the relay, and the high-end floating offset voltage terminal VS is connected to the high-voltage source HVIK through relay K3. The high-voltage source HVIK provides high voltage to VB and VS at the same time. The sum of the currents on VB and VS at this time is tested, which is the high-voltage leakage parameter to be tested.

[0012] Test the short-circuit pulse current of the driver circuit, specifically:

[0013] Connect a resistor to the output end of the driver circuit, input a square wave to the gate of the N-channel MOSFET tube through the digital channel of the tester, obtain a reverse square wave at the drain of the N-channel MOSFET tube, connect the drain to the logic input terminal IN of the driver circuit, and collect the voltage value of the output waveform within one cycle or multiple cycles at the output end of the driver circuit according to the sampling period and sampling interval, and calculate the average value of the collected voltage. The ratio of the average voltage value to the resistance value is the short-circuit pulse current to be detected.

[0014] The present invention has the following beneficial effects and advantages:

[0015] 1. The present invention can use one test device to complete the full parameter test of the entire circuit.

[0016] 2. The present invention can be used on any test machine as long as the hardware specifications of the test machine meet the specification requirements of the circuit itself.

[0017] 3. The present invention only requires one test circuit board to complete the testing needs of the entire circuit, saving testing costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 is a flow chart of the present invention;

[0019] Figure 2 This is the MOSFET driver schematic;

[0020] Figure 3 This is the circuit connection diagram;

[0021] Figure 4 It is the test waveform;

[0022] Figure 5 This is the AC parameter test block diagram;

[0023] Figure 6 This is the block diagram of the driver circuit structure. DETAILED DESCRIPTION

[0024] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0025] A method for testing a high-voltage, high-current suspension driver circuit, comprising:

[0026] The large current is a current with a value exceeding 1A. The test program developer shall select appropriate components to meet the test requirements based on the detailed specifications of the high-end suspension driver circuit or the logic input signal high-level voltage, high-end power supply terminal voltage, high-end suspension offset voltage terminal voltage, high pulse short-circuit current and low pulse short-circuit current values required by foreign documents. Figure 3 As shown, the components include: the MOSFET circuit required for high-level input; the high-voltage relay required for high-end power supply voltage and high-end suspension offset voltage; the filter capacitor required for output AC parameter testing; and the high-current relay and power resistor required for output short-circuit current. The components on the circuit test board were arranged according to the circuit pinout, isolating the high-voltage input section without copper plating. Debugging was performed directly on the tester according to the documentation requirements, completing full parameter testing of the high-voltage and high-current suspension driver, resolving the issues of low digital channel input levels and low measurement voltages.

[0027] A high-voltage, high-current high-end suspension driver circuit test method is to connect the digital channel of the tester to the G terminal of the N-channel MOSFET tube through resistor R1, and the common source of the tester is connected to the D terminal of the MOSFET tube through resistor R2. The other end of resistor R2 is connected to the logic input terminal of the driver circuit to enhance the driving capability of the digital channel of the tester and generate a new waveform as the logic input signal of the driver circuit. Figure 2 As shown. Connect the high-end power supply terminal VB pin of the driver circuit and the H terminal of the floating source PVI in series. The L terminal of the PVI source is connected to the ground through the normally closed terminal of relay K1, and the normally open terminal is connected to the H terminal of the high-voltage source. The H terminal of the high-voltage source HVIK is connected to the high-end floating offset voltage terminal VS of the driver circuit through the normally open terminal of relay K3. The L terminal of the high-voltage source HVIK is grounded, and the normally closed terminal of relay K3 is grounded. The VB and VS pins are short-circuited through relay K2. Figure 1 As shown, by closing the normally open end of relay K1, the floating source and the high-voltage source are connected in series, thereby providing a maximum voltage of 1040V; K1 is in the normally closed state, and the VB pin is in the normal power supply state; K2 is closed and K3 is normally open, thereby providing the same high voltage to VB and VS, while K3 is in the normally closed mode and K2 is open, thereby achieving direct grounding of VS; and K3 is closed in the normally open mode and K2 is open, achieving high-voltage power supply to VS; according to the above description, different operations are performed on the relay according to the test conditions of the driver circuit parameters to achieve full parameter testing.

[0028] like Figure 6As shown in the figure, a driver circuit is used to drive MOSFET components. Its structure generally includes logic inputs, power supplies, outputs, control terminals, and ground terminals. The power supply includes a low-side power supply, which primarily powers the low-side outputs and the device's logic inputs and control terminals. The high-side power supply primarily powers the high-side outputs and, in conjunction with the high-side floating offset voltage terminal, provides a higher voltage for the high-side outputs. As can be seen from the above, the driver's logic input is a key factor in determining the proper function of the device. For example, IR's IR2110L4 requires a high input voltage ≥9.5V and a low input voltage ≤6.0V at room temperature. However, under high and low temperature conditions, the input high voltage must be ≥10V and the input low voltage must be ≤5.7V. For familiar integrated circuit test systems such as the J750, 93000K, Ultra Flex, and STS8205, which have input voltage limits of -2.5V to 7V, this cannot directly meet the testing requirements of circuits like the IR2110L4. Considering that every test system comes with an arbitrary waveform generator, a square wave can be generated using the waveform generator, and then an N-channel MOSFET can be used to enhance the tester's input signal drive capability. This will meet the input level requirements of the driver circuit. The MOSFET selection is based on the input level and AC parameter values of the driver circuit under test.

[0029] like Figure 3 As shown in the documentation, during parameter testing, the voltage difference between the driver's high-side power supply and the high-side floating offset voltage terminal must be 15V, and the voltage at the high-side floating offset voltage terminal must be ≥100V. Therefore, the high-side power supply voltage must be ≥115V. In this case, the test system's floating source is connected in series—that is, a high-voltage source and a floating source are connected in series. The positive terminal of the high-voltage source must be connected to the high-side floating offset voltage terminal, and the floating source connected in series is connected to the high-side power supply terminal. This achieves high-voltage power supply. Taking the IR2110L4 as an example, this circuit requires high voltage to be applied to the circuit during certain parameter tests. The power supply voltage of a typical integrated circuit test system ranges from 40V to 180V. As long as the tester's power supply can be connected in series and meets the test requirements, any tester can be used. The entire circuit test was performed on the STS8205 tester, a domestically produced tester that provides a 1000V high-voltage source and a 40V universal power supply, making it more convenient and flexible to use. The HVIK high-voltage source and FPVI source on the test machine are selected and connected in series through a relay, that is, the L_F and L_S of FPVI are short-circuited with the HVIKH_F and HVIKH_S of the high-voltage source, the H_S and H_F of FPVI are connected to the high-side power supply end, and the HVIKL_S and HVIKL_F are connected to the ground end, so as to meet the test requirements.

[0030] like Figure 4 As shown, when performing AC parameter testing, the output voltage amplitude is basically equal to the high-end power supply voltage, and the time measurement reference point of the AC parameter is at 10% of the rising edge of the input voltage and 90% of the output voltage. For an output voltage of 115V, 90% is 103.5V. The maximum voltage measurement point of the time measurement module of the tester is 25V, which cannot meet the requirements. The AC measurement of the driver circuit generally requires a capacitive load at the output end. Therefore, a capacitor with a withstand voltage greater than 2 times the output voltage is connected to the output end. However, due to the relatively small impedance of the capacitor, direct grounding of the capacitor will introduce very obvious noise. Therefore, a large resistance resistor is connected to the ground at the end of the capacitor. The resistance of the resistor is above KΩ, and the test waveform is smooth and stable.

[0031] When testing the AC parameters of the driver circuit, connect the time measurement units QTMUA and QTMUB of the tester to the logic input terminal and the output terminal of the driver circuit respectively. Figure 5 As shown. Figure 4 The test waveform of the circuit, QTMUA collects the waveform of the logic input end of the driver circuit, and QTMUB collects the waveform of the output end of the driver circuit. Taking the test of the AC parameter Ton as an example, first observe the measurement range of Ton in the test waveform diagram, the time difference between 50% of the rising edge of the input waveform and 10% of the rising edge of the output waveform, so before the test, the voltage values of these two points must be set in the program. QTMUA will collect this voltage value according to the voltage value set in the test program and use it as the reference voltage. The time at this time is used as the reference time. At the same time, QTMUB collects the voltage value and time value set at the output end, and the difference between these two time values is Ton.

[0032] When performing the high-voltage leakage test required in the documentation, it is necessary to connect the high-end power supply terminal and the high-end floating offset voltage terminal together through a relay, or directly connect the high-end floating offset voltage terminal to the high-voltage source. At this time, it is important to note that the leakage current is very small, generally at the microampere level. During the PCB production process, the output terminals of the components involved in the high-voltage source leakage current test cannot be copper-plated, otherwise it will cause large leakage current and cause misjudgment of the circuit. Therefore, in the PCB layout, high-voltage components, high-voltage output terminals, etc. should be placed in the same area and isolated from the copper-plated area;

[0033] When testing the high-voltage leakage parameters of the driver circuit, short-circuit the high-end power supply terminal VB and the high-end floating offset voltage terminal VS through a relay, connect the high-end floating offset voltage terminal VS to a high-voltage source through a relay, and provide high voltage to VB and VS at the same time through the high-voltage source. Test the sum of the currents on the VB and VS pins at this time.

[0034] According to the requirements of the driver data, a short-circuit pulse current test is required. Generally, the short-circuit pulse current value is above 1A, and the effective pulse duration is 10μs. According to the current technical indicators of the analog integrated circuit test system, it is not possible to measure the current using a source. The fastest measurement speed of the source is 10μs. Therefore, the voltage measurement module on the test machine is used. The suspension driver is used as a driver for the MOSFET circuit, and the on-resistance of the MOSFET is very small, so the resistor selected at the output end should preferably be within 100mΩ. In the test program, compile as many vectors as possible, but only one vector in the middle is the required low pulse or high pulse. However, it is necessary to collect the output of all vectors, compare the expected test results with the actual measurement results, find the collection point of the required test results, select 30-80 points after this collection point for data collection, and calculate the average voltage to obtain the short-circuit current.

[0035] The high voltage and high current driver circuit test method provided by the embodiment of the present application can complete the conversion of input high level and low level from low voltage to high voltage according to the circuit data, thereby meeting the circuit input conditions; by connecting the high voltage source and the floating source in series, with the help of the high voltage relay, the voltage difference between the high-end power supply end and the high-end floating offset voltage end is achieved to meet the test condition requirements, thereby smoothly realizing the AC parameter test; for short pulse current testing, a small resistor is connected to the output end, multiple sets of data are collected, and the ampere-level short-circuit current test is realized by analyzing the data; in the production of the test circuit board, the high voltage related parts are placed in one area, and copper plating is not used to avoid excessive leakage current and misjudgment. Through the above description, by selecting different components, full parameter testing of high voltage and high current driver circuits can be achieved.

[0036] Example 1

[0037] Figure 1 This is a flow chart of a test method for a high voltage, high current driver circuit provided in Example 1 of this patent. This embodiment is applicable to the test of high voltage, high current circuits, as follows:

[0038] 1. Check whether the high-level voltage and low-level voltage values of the logic input signal in the circuit data meet the requirements of the tester. If not, use a MOSFET circuit to drive the logic input signal of the tester so that the MOSFET output signal meets the requirements of the driver circuit.

[0039] 2. Under the test conditions, the maximum voltage required by the high-end power supply terminal and the high-end floating offset voltage terminal is determined by the voltage provider of the high-end floating offset voltage terminal. If the voltage exceeds the voltage that the test machine source can provide, the high-voltage source and floating source series mode is adopted. In the series mode, all relays use high-voltage relays, and any device directly connected to the high-voltage pin needs to use a high-voltage relay for safety. It is also required that the current limiting range of the high-voltage source cannot be less than the current limiting range of the floating source in series with it.

[0040] 3. According to 1 and 2, the functional test of the driver circuit can be realized. The corresponding input and output waveforms can be observed through the oscilloscope, but the test machine cannot normally collect the voltage value of the output end. Therefore, a capacitive load is connected to the output end. The withstand voltage value of the capacitive load should be twice the voltage value of the high-end floating offset voltage end. In order to reduce noise, a resistor with a resistance value of more than KΩ is connected to the end of the capacitive load. At this time, the test machine can measure DC parameters and AC parameters between the capacitive load and the resistor.

[0041] 4. Based on the functional test of the driver circuit that can be achieved according to 1 and 2, a small resistor of less than 100mΩ is connected to the output end through a high-current relay. When measuring high pulse short-circuit current, the test vector is invalid at the beginning. Among the 100 compiled vectors, only one vector is valid, and the effective pulse width of the vector is 10μS. The voltage across the resistor is measured using the voltmeter of the test machine. The sampling time of the voltmeter is 0.1μS. 10,000 data are collected in 100 vectors, and these data are judged. The data that meets the requirements are counted, and the short-circuit voltage is obtained by calculating the average value, and the short-circuit current is never obtained.

[0042] 5. For other parameters in the data, they can be applied according to the test conditions to complete the full parameter test of the circuit.

Claims

1. A high voltage and high current high end suspension driver circuit test system, characterized in that: It includes an N-channel MOSFET tube, a driver circuit, multiple resistors and multiple relays, wherein: the gate of the N-channel MOSFET tube is connected to the digital channel of the test machine through a resistor R1, the drain of the N-channel MOSFET tube is respectively connected to the logic input terminal IN of the driver circuit and the common power supply terminal FOVI-0 of the test machine through a resistor R2, the high-end power supply terminal VB of the driver circuit is connected to the H end of the floating power supply FPVI-0 of the test machine, the high-end floating offset voltage terminal VS of the driver circuit is connected to the H end of the high-voltage source HVIK of the test machine through a relay K3, the H end of the floating power supply FPVI-0 of the test machine is connected to the H end of the high-voltage source HVIK of the test machine through relays K2 and K3 in sequence, and the L end of the floating power supply FPVI-0 of the test machine is connected to the H end of the high-voltage source HVIK of the test machine through a relay K1.

2. A high-voltage and high-current high-end suspension driver circuit testing method, applied to a high-voltage and high-current high-end suspension driver circuit testing system according to claim 1, characterized in that: The square wave output by the tester is input into the driver circuit through the N-channel MOSFET tube, and the high-end power supply terminal VB of the driver circuit, the high-end floating offset voltage terminal VS, the floating power supply FPVI-0 of the tester and the high-voltage source HVIK of the tester are connected through different relays. By controlling the on and off of different relays, the AC parameters, high-voltage leakage parameters and short-circuit pulse current of the driver circuit are tested respectively.

3. A high voltage and high current high end suspension driver circuit testing method according to claim 2, characterized in that: Test the AC parameters of the driver circuit, specifically: Set the voltage threshold A of the logic input terminal IN and the voltage threshold B of the output terminal of the driver circuit. When the voltage value of the logic input terminal IN reaches threshold A, the time at this time is used as reference time 1. When the voltage value of the output terminal reaches threshold B, the time at this time is used as reference time 2. The difference between reference time 2 and reference time 1 is the AC parameter to be tested.

4. A high-voltage and high-current high-end suspension driver circuit testing method according to claim 2, characterized in that: Test the high voltage leakage parameters of the driver circuit, specifically: By controlling the relay K2, the high-end power supply terminal VB and the high-end suspension offset voltage terminal VS are short-circuited through the relay, and the high-end suspension offset voltage terminal VS is connected to the high-voltage source HVIK through the relay K3. The high-voltage source HVIK provides high voltage to the high-end power supply terminal VB of the driver circuit and the high-end suspension offset voltage terminal VS of the driver circuit at the same time. The sum of the currents on the high-end power supply terminal VB of the driver circuit and the high-end suspension offset voltage terminal VS of the driver circuit at this time is tested, which is the high-voltage leakage parameter to be tested.

5. The method for testing a high-voltage and high-current high-end suspension driver circuit according to claim 2, wherein: Test the short-circuit pulse current of the driver circuit, specifically: Connect a resistor to the output end of the driver circuit, input a square wave to the gate of the N-channel MOSFET tube through the digital channel of the tester, obtain a reverse square wave at the drain of the N-channel MOSFET tube, connect the drain to the logic input terminal IN of the driver circuit, and collect the voltage value of the output waveform within one cycle or multiple cycles at the output end of the driver circuit according to the sampling period and sampling interval, and calculate the average value of the collected voltage. The ratio of the average voltage value to the resistance value is the short-circuit pulse current to be detected.

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