Dynamic On-Resistance Test Platform and Method

Abstract

This invention relates to the field of semiconductor switching device testing, and provides a dynamic on-resistance testing platform and method. The dynamic on-resistance testing platform includes a dynamic testing circuit and a control device. The dynamic testing circuit includes a high-voltage source meter and a current-limiting unit connected in series with the semiconductor switching device to form a loop, as well as a clamping circuit, a current and voltage acquisition device, and a driving circuit. The control device contains a control program that controls the dynamic testing circuit to perform current and voltage calibration to obtain current and voltage correction coefficients respectively, controls the dynamic testing circuit to perform dynamic on-resistance testing and obtain test data, and uses the test data, current correction coefficients, and voltage correction coefficients to obtain the corrected dynamic resistance value corresponding to the semiconductor switching device. The dynamic on-resistance testing method performs dynamic on-resistance testing on semiconductor switching devices based on the above-described dynamic on-resistance testing platform. This invention can improve the accuracy of dynamic on-resistance testing.

Description

Technical Field

[0001] This invention relates to the field of testing semiconductor switching devices, and more specifically to a system and method for testing dynamic on-resistance during rapid switching processes. Background Technology

[0002] As switching power supplies evolve towards higher frequencies, higher efficiency, and smaller sizes, the requirements for power switching devices are becoming increasingly demanding, and traditional silicon devices are no longer sufficient. Currently, GaN and SiC, as third-generation semiconductor materials, offer significant advantages over first-generation Si and second-generation GaAs. AlGaN / GaN HEMTs possess a large bandgap, high peak saturation electron velocity, high concentration of two-dimensional electrons, and high electron mobility, making them widely used in RF, microwave, and power switching fields.

[0003] Conventional AlGaN / GAN HEMTs are lateral devices with channels in an extremely thin two-dimensional electron gas region. During turn-off, the large local electric field easily causes electron trapping, leading to current collapse and resulting in high dynamic resistance. Accurate characterization of this dynamic resistance is crucial. Furthermore, since trapping is partially recoverable, the applied voltage, whether hard switching is used, and the waiting time after high voltage are applied all significantly affect the dynamic resistance reading. Additionally, dynamic resistance must be tested in the on-state after high voltage turn-off. Typically, the drain-source voltage and drain-source current are measured during on-state to calculate the dynamic resistance. However, the voltage drop across the drain-source terminals after the device is on is much lower than in the off-state. If the test equipment's range also accommodates the off-state voltage drop, the measurement accuracy of the on-state voltage drop will be very low, making it impossible to measure. Therefore, clamping circuitry is required. Currently used dynamic resistance testing platforms primarily employ clamping circuitry at the device under test (DUT) location to measure the on-state voltage drop. Simultaneously, current is measured through a current-sensing resistor, coaxial shunt, or current probe in the loop to calculate the on-state resistance.

[0004] The main problem with current dynamic resistance testing platforms is that, due to the often large conduction current, short conduction time, and low duty cycle, only an oscilloscope can be used as the measurement device. The resistance range of the devices under test is very wide, often ranging from a few milliohms to several ohms, which translates to a voltage measurement on the oscilloscope between milliohms and ohms, limiting the oscilloscope's measurement accuracy. Furthermore, the long test circuit loop causes oscillations, and although clamping circuits isolate high voltage, oscillating voltages often occur during switching, resulting in the upper and lower limits of the waveform captured by the oscilloscope being much larger than the actual on-state voltage drop of the device under test. This further reduces the accuracy of the on-state voltage drop measurement. The low testing accuracy of current dynamic resistance testing platforms is a problem that urgently needs to be solved. Summary of the Invention

[0005] The technical problem solved by this invention is to improve the testing accuracy of the dynamic on-resistance of semiconductor switching devices, thereby providing a reliable guarantee for their application.

[0006] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows:

[0007] A dynamic on-resistance testing platform for testing the dynamic on-resistance of semiconductor switching devices, comprising:

[0008] A dynamic test circuit includes a high-voltage source meter, a current limiting unit, a clamping circuit, a current and voltage capturing device, and a driving circuit. The high-voltage source meter, the current limiting unit, and the semiconductor switching device are connected in series to form a loop. The clamping circuit is connected in parallel with the semiconductor switching device and has an output terminal. The current and voltage capturing device is connected to the output terminal of the clamping circuit. The driving circuit is connected to the gate of the semiconductor switching device.

[0009] The control device includes a control program that controls the dynamic test circuit to perform current and voltage calibrations and obtain current and voltage correction coefficients, respectively. The control device also controls the dynamic test circuit to perform dynamic on-resistance testing on the semiconductor switching device and obtain test data. Furthermore, the control device uses the test data, the current correction coefficient, and the voltage correction coefficient to obtain the corrected dynamic resistance value of the semiconductor switching device.

[0010] Furthermore, the current limiting unit includes a current limiting resistor or an inductor and diode connected in parallel, and the dynamic test circuit also includes a switch connected in parallel with the current limiting unit.

[0011] This invention also provides a dynamic on-resistance testing method for semiconductor switching devices based on the aforementioned dynamic on-resistance testing platform, the method comprising the following steps:

[0012] Step 1: Preset the parameters required for dynamic on-resistance testing;

[0013] Step 2: Perform current calibration and voltage calibration on the dynamic test circuit, and obtain the current correction coefficient and voltage correction coefficient respectively;

[0014] Step 3: Use the dynamic test circuit to perform dynamic on-resistance testing on the semiconductor switching device and obtain test data;

[0015] Step 4: Using the test data, the current correction factor, and the voltage correction factor, obtain the corrected dynamic resistance value corresponding to the semiconductor switching device.

[0016] In step 1, when the current limiting unit includes a current limiting resistor, the parameters include the resistance value of the current limiting resistor, the upper limit of the voltage required for voltage calibration, and the lower limit of the voltage required for voltage calibration; or the parameters include the resistance value of the current limiting resistor, the test high voltage value of the dynamic resistance, the typical value of the dynamic resistance of the semiconductor switching device, and the voltage fluctuation ratio.

[0017] When the parameters include the resistance value of the current-limiting resistor, the test high voltage value of the dynamic resistance, the typical value of the dynamic resistance of the semiconductor switching device, and the voltage fluctuation ratio, the upper limit voltage value and the lower limit voltage value required for voltage calibration are calculated using the parameters.

[0018] In step 1, when the current limiting unit includes an inductor and a diode connected in parallel, the parameters include the upper limit of the voltage required for voltage calibration and the lower limit of the voltage required for voltage calibration, or the parameters include the equivalent resistance of the current limiting unit, the high voltage value of the dynamic resistance test, the typical value of the dynamic resistance of the semiconductor switching device, and the voltage fluctuation ratio.

[0019] When the parameters include the equivalent resistance of the current limiting unit, the test high voltage value of the dynamic resistance, the typical value of the dynamic resistance of the semiconductor switching device, and the voltage fluctuation ratio, the upper limit voltage value and the lower limit voltage value required for voltage calibration are calculated using the parameters.

[0020] The method for calculating the upper limit and lower limit of the voltage required for voltage calibration is as follows: Current value during dynamic conduction ≈ Test high voltage value of dynamic resistor / Resistance value of current-limiting resistor; or Current value during dynamic conduction ≈ Test high voltage value of dynamic resistor / Equivalent resistance value of current-limiting unit; Detected voltage value of current-voltage sensing device during dynamic conduction ≈ Typical dynamic resistance value of semiconductor switching device * Current value during dynamic conduction; Upper limit of voltage required for voltage calibration = Detected voltage value of current-voltage sensing device during dynamic conduction * (1 + Voltage fluctuation ratio); Lower limit of voltage required for voltage calibration = Detected voltage value of current-voltage sensing device during dynamic conduction * (1 - Voltage fluctuation ratio); The voltage fluctuation ratio ranges from 10% to 50%.

[0021] In step 2, when the current limiting unit includes a current limiting resistor, the method for current calibration is as follows: control the semiconductor switching device to open, use the high voltage source meter to test the resistance value of the loop, and calculate the current correction coefficient = resistance value of the current limiting resistor / resistance value of the loop.

[0022] In step 2, when the current limiting unit includes an inductor and a diode connected in parallel, the current calibration method is as follows: control the semiconductor switching device to open, control the high-voltage source meter to output one or more current signals, and the current value of the current signal output by the high-voltage source meter is within a set current range; when the high-voltage source meter outputs one current signal, use the current-voltage capturing device to capture the current value of a corresponding detection point, and calculate the current correction coefficient = the current value of the detection point / the current value of the current signal or the current correction coefficient = the current value of the detection point - the current value of the current signal; when the high-voltage source meter outputs multiple current signals, use the current-voltage capturing device to capture the current values ​​of multiple corresponding detection points respectively, and then use the current value of the detection point and the current value of the current signal to perform linear fitting to obtain the current correction coefficient.

[0023] The method for voltage calibration is as follows: The semiconductor switching device is turned off, the current limiting unit is short-circuited, and the high-voltage source meter is controlled to output one or more voltage signals. The voltage value of the voltage signal output by the high-voltage source meter is within the voltage range defined by the upper limit and lower limit of the voltage required for voltage calibration. When the high-voltage source meter outputs one voltage signal, the current-voltage capturing device captures the voltage value of a corresponding detection point, and the voltage correction coefficient is calculated as: voltage value of the voltage signal / voltage value of the detection point. When the high-voltage source meter outputs multiple voltage signals, the current-voltage capturing device captures the voltage values ​​of multiple corresponding detection points respectively, and the voltage correction coefficient is obtained by linearly fitting the voltage values ​​of the voltage signals with the corresponding detection point voltage values.

[0024] In step 3, when performing dynamic on-resistance testing, the current and voltage capturing device is used to capture the test current value and / or test voltage value as the test data.

[0025] In step 4, the test current value is corrected using the current correction coefficient to obtain a corrected current value, and the test voltage value is corrected using the voltage correction coefficient to obtain a corrected voltage value. Then, the corrected dynamic resistance value corresponding to the semiconductor switching device is obtained using the corrected current value and the corrected voltage value.

[0026] Specifically, in step 4, firstly, the initial value of the dynamic resistance of the semiconductor switching device is calculated as: the test voltage value / the current value when the semiconductor switching device is dynamically turned on; the voltage correction coefficient includes a voltage correction slope coefficient, or the voltage correction coefficient includes a voltage correction slope coefficient and a voltage correction intercept coefficient; then, the corrected dynamic resistance value corresponding to the semiconductor switching device is calculated as: the initial value of the dynamic resistance of the semiconductor switching device * the current correction coefficient * the voltage correction slope coefficient, or the corrected dynamic resistance value corresponding to the semiconductor switching device = the initial value of the dynamic resistance of the semiconductor switching device * the current correction coefficient * the voltage correction slope coefficient + the voltage correction intercept coefficient.

[0027] Due to the application of the above technical solutions, the present invention has the following advantages compared with the prior art: the present invention can accurately calibrate the conduction voltage and conduction current of semiconductor switching devices, thereby improving the test accuracy of their dynamic conduction resistance test. Attached Figure Description

[0028] Appendix Figure 1 This is a circuit diagram of the dynamic test circuit according to Embodiment 1 of the present invention.

[0029] Appendix Figure 2 This is a circuit diagram of the dynamic test circuit according to Embodiment 2 of the present invention.

[0030] In the above attached diagram: 1. Semiconductor switching device; 2. Clamping circuit; 3. Current limiting unit; 4. Current and voltage sensing device; 5. High voltage source meter; 6. Bus capacitor; 7. Bus switch; 8. Current sensing resistor. Detailed Implementation

[0031] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0032] Example 1: A dynamic on-resistance testing platform, which includes a dynamic testing circuit and a control device.

[0033] As attached Figure 1As shown, the dynamic test circuit includes a high-precision high-voltage source meter, a current-limiting unit, a clamping circuit, a current and voltage acquisition device, and a drive circuit. The high-voltage source meter, the current-limiting unit, and the semiconductor switching device are connected in series to form a loop. The clamping circuit is connected in parallel with the semiconductor switching device and has an output terminal. The current and voltage acquisition device is connected to the output terminal of the clamping circuit for measuring the on-state voltage drop of the semiconductor switching device. The drive circuit is connected to the gate of the semiconductor switching device. The current-limiting unit uses a current-limiting resistor, and a switch capable of short-circuiting it is connected in parallel with the current-limiting resistor; the current and voltage acquisition device uses an oscilloscope. This dynamic test circuit may also include a bus capacitor and a bus switch connected in series and then in parallel across the high-voltage source meter.

[0034] The control device is connected to the aforementioned dynamic test circuit, such as a high-voltage source meter, current and voltage acquisition device, or bus switch, to control them and acquire data. The control device contains a control program specifically used for: ① controlling the dynamic test circuit to perform current and voltage calibration and obtain current and voltage correction coefficients respectively; ② controlling the dynamic test circuit to perform dynamic on-resistance testing on semiconductor switching devices and obtain test data; ③ using the test data, current correction coefficients, and voltage correction coefficients to obtain the corrected dynamic resistance value of the semiconductor switching device.

[0035] Based on the aforementioned dynamic on-resistance testing platform, the specific method for testing the dynamic on-resistance of semiconductor switching devices is as follows:

[0036] Step 1: Preset the parameters required for dynamic on-resistance testing.

[0037] This step is implemented using a control device. The parameters set include the resistance value R1 of the current-limiting resistor, the upper limit voltage V3 required for voltage calibration, and the lower limit voltage V4 required for voltage calibration. Alternatively, the parameters set may include the resistance value R1 of the current-limiting resistor, the high test voltage V1 for dynamic resistance, the typical dynamic resistance value R2 of the semiconductor switching device, and the voltage fluctuation percentage x%. Furthermore, the turn-off voltage, on-state current, turn-off time and on-state time of the semiconductor switching device, and the number of switching operations can be set for the dynamic on-resistance test process.

[0038] For the case where the set parameters include the resistance value R1 of the current limiting resistor, the test high voltage value V1 of the dynamic resistance, the typical value of the dynamic resistance of the semiconductor switching device R2, and the voltage fluctuation ratio x%, the control device needs to calculate the upper limit voltage value V3 and the lower limit voltage value V4 required for voltage calibration based on these parameters.

[0039] The method for calculating the upper limit voltage V3 and the lower limit voltage V4 required for voltage calibration is as follows:

[0040] 1) Using the test high voltage value V1 of the dynamic resistor and the resistance value R1 of the current limiting resistor, calculate the current value I1 ≈ V1 / R1 when the dynamic conduction is on. The current value I1 when the dynamic conduction is on is an estimated value.

[0041] 2) Using the current value I1 during dynamic conduction and the typical dynamic resistance value R2 of the semiconductor switching device, calculate the detection voltage value V2≈R2*I1 of the current and voltage capture device during dynamic conduction. The detection voltage value of the current and voltage capture device during dynamic conduction is an estimated value.

[0042] 3) Using the detected voltage value V2 and voltage fluctuation ratio x% from the dynamic conduction current and voltage capture device, calculate the upper limit voltage required for voltage calibration V3 = V2*(1+x%) and the lower limit voltage required for voltage calibration V4 = V2*(1-x%). Thus, V4~V3 constitute the acceptable voltage range. The voltage fluctuation ratio x% typically ranges from 10% to 50%.

[0043] Step 2: Perform current calibration and voltage calibration on the dynamic test circuit, and obtain the current correction coefficient and voltage correction coefficient respectively.

[0044] This step is accomplished in conjunction with a control device and a dynamic test circuit. The appropriate program is selected within the control device to implement the following current and voltage calibration methods.

[0045] The current calibration method is as follows: if there is a bus capacitor, it is disconnected through the bus switch connected in series, and the semiconductor switching device is turned on. The resistance value R of the loop (including the current-limiting resistor R1, the conducting semiconductor switching device, and other resistors in the loop) is directly measured using a high-precision high-voltage source meter, and then the current correction factor a1 is calculated as: resistance value of the current-limiting resistor / resistance value of the loop, i.e., a1 = R1 / R.

[0046] The voltage calibration method is as follows: If there is a bus capacitor, it is disconnected through the bus switch connected in series, the semiconductor switching device is turned off, and the switch short-circuit current limiting unit is used. The high-voltage source meter is controlled to output one or more voltage signals. The voltage value of the voltage signal output by the high-voltage source meter is within the voltage range defined by the upper limit V3 and the lower limit V4 required for voltage calibration. When the high-voltage source meter outputs one voltage signal, the voltage value at the corresponding detection point is captured using a current-voltage capture device, and the voltage correction coefficient a2 is calculated as: voltage value of the voltage signal / voltage value at the detection point. When the high-voltage source meter outputs multiple voltage signals, the voltage values ​​at the corresponding multiple detection points are captured using the current-voltage capture device, and the voltage correction coefficient a2 is obtained by linearly fitting the voltage values ​​of the voltage signals with the corresponding detection point voltage values.

[0047] Taking dual-point calibration as an example, the high-voltage source meter outputs a voltage signal equal to the upper voltage limit V3, and the oscilloscope captures the corresponding detection point voltage value V5. Then, the high-voltage source meter outputs a voltage signal equal to the lower voltage limit V4, and the oscilloscope captures the corresponding detection point voltage value V6. Linear fitting is performed on the two input voltages V3 and V4 and the two detection voltages V5 and V6, i.e., V3 = a2*V5 + b2, V4 = a2*V6 + b2. This yields a2 = (V3 - V4) / (V5 - V6), and b2 = V3 - a2*V5. In this case, the voltage correction coefficient includes the voltage correction slope coefficient a2 and the voltage correction intercept coefficient b2. However, when using single-point calibration, the voltage correction coefficient may only include the voltage correction slope coefficient a2.

[0048] Step 3: Use a dynamic test circuit to perform dynamic on-resistance testing on the semiconductor switching device and obtain test data.

[0049] This step is completed collaboratively by a control device and a dynamic test circuit. The semiconductor switching device is controlled to be in the off state, and a high-voltage source meter outputs a high voltage. If there is a bus capacitor in the circuit, a certain waiting time is provided to charge the capacitor. The device under test is controlled to perform a pulse-on test for dynamic on-resistance testing. When the device is in a stable position at the moment of conduction, a current-voltage capture device captures the test current value and / or test voltage value as test data and uploads it to the control device. For example, the oscilloscope is triggered to capture the output voltage V7 from the clamping voltage circuit; that is, the current-voltage capture device captures the test voltage value V7 as test data and uploads it to the control device.

[0050] Step 4: Use the test data and the current correction factor and voltage correction factor to obtain the corrected dynamic resistance value of the semiconductor switching device.

[0051] This step is implemented using a control device. The test current value is corrected using a current correction factor to obtain a corrected current value, and the test voltage value is corrected using a voltage correction factor to obtain a corrected voltage value. Then, the corrected dynamic resistance value of the semiconductor switching device is obtained using the corrected current value and the corrected voltage value.

[0052] For example, when only capturing the test voltage value V7, first calculate the initial dynamic resistance value R3 of the semiconductor switching device = test voltage value / current value when the semiconductor switching device is dynamically turned on, i.e., R3 = V7 / I1; then calculate the corrected dynamic resistance value R4 of the semiconductor switching device = initial dynamic resistance value of the semiconductor switching device * current correction coefficient * voltage correction slope coefficient, i.e., R4 = R3 * a1 * a2, or the corrected dynamic resistance value R4 of the semiconductor switching device = initial dynamic resistance value of the semiconductor switching device * current correction coefficient * voltage correction slope coefficient + voltage correction intercept coefficient, i.e., R4 = R3 * a1 * a2 + b2.

[0053] The above-described dynamic on-resistance testing method can obtain a more accurate corrected dynamic resistance value R4 for semiconductor switching devices, thereby improving the testing accuracy.

[0054] Example 2: A dynamic on-resistance testing platform, comprising a dynamic testing circuit and a control device. The difference from Example 1 is that the current-limiting unit in the dynamic testing circuit includes a parallel inductor and a diode, a current-sensing resistor 8 is connected in series in the loop of the dynamic testing circuit, and a method for current and voltage calibration of the current-limiting unit is provided.

[0055] For this dynamic on-resistance test platform and the dynamic on-resistance test method implemented thereunder, the preset required parameters include the upper limit of voltage required for voltage calibration and the lower limit of voltage required for voltage calibration, or the parameters include the equivalent resistance of the current limiting unit, the high voltage value for dynamic resistance testing, the typical value of dynamic resistance of semiconductor switching devices, and the voltage fluctuation ratio.

[0056] Similarly, in step 1, when the parameters include the equivalent resistance of the current limiting unit, the test high voltage value of the dynamic resistance, the typical value of the dynamic resistance of the semiconductor switching device, and the voltage fluctuation ratio, the upper limit voltage value and the lower limit voltage value required for voltage calibration are calculated using the parameters.

[0057] The method for calculating the upper voltage limit V3 and the lower voltage limit V4 required for voltage calibration of the dynamic on-resistance test platform is as follows: Calculate the current value I1 during dynamic on-state operation approximately equal to the high test voltage value V1 of the dynamic resistance / the equivalent resistance value R1 of the current-limiting unit. Calculate the detection voltage value V2 of the current-voltage capture device during dynamic on-state operation approximately equal to the typical dynamic resistance value R2 of the semiconductor switching device * the current value I1 during dynamic on-state operation. Calculate the upper voltage limit V3 required for voltage calibration as V2 * (1 + voltage fluctuation ratio). Calculate the lower voltage limit V4 required for voltage calibration as V2 * (1 - voltage fluctuation ratio). The voltage fluctuation ratio also ranges from 10% to 50%.

[0058] In step 2, the current calibration method is as follows: The semiconductor switching device is turned on, and the high-voltage source meter outputs one or more current signals. The current value of the current signal output by the high-voltage source meter is within a set current range. When the high-voltage source meter outputs a single current signal, the current-voltage capturing device captures the current value at a corresponding detection point, and the current correction coefficient a1 is calculated as: Detection point current value / Current signal value, or Detection point current value - Current signal value. The correction effect of the current correction coefficient calculated using the current ratio is greater than that calculated using the current difference. When the high-voltage source meter outputs multiple current signals, the current-voltage capturing device captures the current values ​​at multiple corresponding detection points respectively. The current correction coefficient a1 is then obtained by linearly fitting the detection point current values ​​with the current signal values.

[0059] The voltage calibration method is as follows: The semiconductor switching device is turned off, the current-limiting unit is short-circuited, and the high-voltage source meter outputs one or more voltage signals. The voltage value of the output voltage signal is within the range defined by the upper voltage limit V3 and the lower voltage limit V4 required for voltage calibration. When the high-voltage source meter outputs one voltage signal, the voltage value at the corresponding detection point is captured using a current-voltage capture device, and the voltage correction coefficient a2 is calculated as: voltage value of the voltage signal / voltage value at the detection point. When the high-voltage source meter outputs multiple voltage signals, the voltage values ​​at the corresponding multiple detection points are captured using the current-voltage capture device, and the voltage correction coefficient a2 is obtained by linearly fitting the voltage values ​​of the voltage signals with the corresponding detection point voltage values.

[0060] The above scheme, through current correction and voltage correction, can calibrate the on-state voltage drop test value and on-state current test value of the north side, thereby improving the test accuracy.

[0061] The above embodiments are only for illustrating the technical concept and features of the present invention, and are intended to enable those skilled in the art to understand the content of the present invention and implement it accordingly. They should not be construed as limiting the scope of protection of the present invention. All equivalent changes or modifications made in accordance with the spirit and essence of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A dynamic on-resistance testing platform for testing the dynamic on-resistance of semiconductor switching devices, characterized in that: The dynamic on-resistance testing platform includes: A dynamic test circuit includes a high-voltage source meter, a current-limiting unit, a clamping circuit, a current and voltage acquisition device, and a driving circuit. The high-voltage source meter, the current-limiting unit, and the semiconductor switching device are connected in series to form a loop. The clamping circuit is connected in parallel with the semiconductor switching device and has an output terminal. The current and voltage acquisition device is connected to the output terminal of the clamping circuit. The driving circuit is connected to the gate of the semiconductor switching device. The current-limiting unit includes a current-limiting resistor or a parallel inductor and diode. The dynamic test circuit also includes a switch connected in parallel with the current-limiting unit. The control device includes a control program that controls the dynamic test circuit to perform current calibration and voltage calibration and obtain current correction coefficients and voltage correction coefficients respectively; controls the dynamic test circuit to perform dynamic on-resistance testing on the semiconductor switching device and obtain test data; and the control device also uses the test data, the current correction coefficients, and the voltage correction coefficients to obtain the corrected dynamic resistance value of the semiconductor switching device. The dynamic on-resistance testing method for semiconductor switching devices using the aforementioned dynamic on-resistance testing platform includes the following steps: Step 1: Preset the parameters required for dynamic on-resistance testing; Step 2: Perform current calibration and voltage calibration on the dynamic test circuit, and obtain the current correction coefficient and voltage correction coefficient respectively; Step 3: Use the dynamic test circuit to perform dynamic on-resistance testing on the semiconductor switching device and obtain test data; Step 4: Using the test data, the current correction factor, and the voltage correction factor, obtain the corrected dynamic resistance value corresponding to the semiconductor switching device; In step 2, when the current limiting unit includes a current limiting resistor, the method for current calibration is as follows: control the semiconductor switching device to open, use the high voltage source meter to test the resistance value of the loop, and calculate the current correction coefficient = resistance value of the current limiting resistor / resistance value of the loop. In step 2, when the current limiting unit includes an inductor and a diode connected in parallel, the current calibration method is as follows: control the semiconductor switching device to open, control the high-voltage source meter to output one or more current signals, and the current value of the current signal output by the high-voltage source meter is within a set current range; when the high-voltage source meter outputs one current signal, use the current-voltage capturing device to capture the current value of a corresponding detection point, and calculate the current correction coefficient = the current value of the detection point / the current value of the current signal; when the high-voltage source meter outputs multiple current signals, use the current-voltage capturing device to capture the current values ​​of multiple corresponding detection points respectively, and then use the current value of the detection point current and the current value of the current signal to perform linear fitting to obtain the current correction coefficient; In step 2, the voltage calibration method is as follows: The semiconductor switching device is turned off, the current limiting unit is short-circuited, and the high-voltage source meter is controlled to output one or more voltage signals. The voltage value of the voltage signal output by the high-voltage source meter is within the voltage range defined by the upper limit and lower limit of the voltage required for voltage calibration. When the high-voltage source meter outputs one voltage signal, the current-voltage capturing device captures the voltage value of a corresponding detection point, and the voltage correction coefficient is calculated as: voltage value of the voltage signal / voltage value of the detection point. When the high-voltage source meter outputs multiple voltage signals, the current-voltage capturing device captures the voltage values ​​of multiple corresponding detection points respectively, and the voltage correction coefficient is obtained by linearly fitting the voltage value of the voltage signal with the corresponding voltage value of the detection point. In step 4, firstly, the initial value of the dynamic resistance of the semiconductor switching device is calculated as: the test voltage value / the current value when the semiconductor switching device is dynamically turned on. The current value when the semiconductor switching device is dynamically turned on is approximately equal to the test high voltage value of the dynamic resistance / the resistance value of the current-limiting resistor, or the current value when the semiconductor switching device is dynamically turned on is approximately equal to the test high voltage value of the dynamic resistance / the equivalent resistance value of the current-limiting unit. The voltage correction coefficient includes a voltage correction slope coefficient, or the voltage correction coefficient includes a voltage correction slope coefficient and a voltage correction intercept coefficient. Then, the corrected dynamic resistance value corresponding to the semiconductor switching device is calculated as: the initial value of the dynamic resistance of the semiconductor switching device * the current correction coefficient * the voltage correction slope coefficient, or the corrected dynamic resistance value corresponding to the semiconductor switching device = the initial value of the dynamic resistance of the semiconductor switching device * the current correction coefficient * the voltage correction slope coefficient + the voltage correction intercept coefficient.

2. The dynamic on-resistance testing platform according to claim 1, characterized in that: In step 1, when the current limiting unit includes a current limiting resistor, the parameters include the resistance value of the current limiting resistor, the upper limit of the voltage required for voltage calibration, and the lower limit of the voltage required for voltage calibration; or the parameters include the resistance value of the current limiting resistor, the test high voltage value of the dynamic resistance, the typical value of the dynamic resistance of the semiconductor switching device, and the voltage fluctuation ratio. When the parameters include the resistance value of the current-limiting resistor, the test high voltage value of the dynamic resistor, the typical value of the dynamic resistance of the semiconductor switching device, and the voltage fluctuation ratio, the upper limit voltage value and the lower limit voltage value required for voltage calibration are calculated using the parameters. In step 1, when the current limiting unit includes an inductor and a diode connected in parallel, the parameters include the upper limit of the voltage required for voltage calibration and the lower limit of the voltage required for voltage calibration, or the parameters include the equivalent resistance of the current limiting unit, the high voltage value of the dynamic resistance test, the typical value of the dynamic resistance of the semiconductor switching device, and the voltage fluctuation ratio. When the parameters include the equivalent resistance of the current limiting unit, the test high voltage value of the dynamic resistance, the typical value of the dynamic resistance of the semiconductor switching device, and the voltage fluctuation ratio, the upper limit voltage value and the lower limit voltage value required for voltage calibration are calculated using the parameters.

3. The dynamic on-resistance testing platform according to claim 2, characterized in that: The method for calculating the upper limit and lower limit of the voltage required for voltage calibration is as follows: Current value during dynamic conduction ≈ Test high voltage value of dynamic resistor / Resistance value of current-limiting resistor; or Current value during dynamic conduction ≈ Test high voltage value of dynamic resistor / Equivalent resistance value of current-limiting unit; Detected voltage value of current-voltage sensing device during dynamic conduction ≈ Typical dynamic resistance value of semiconductor switching device * Current value during dynamic conduction; Upper limit of voltage required for voltage calibration = Detected voltage value of current-voltage sensing device during dynamic conduction * (1 + Voltage fluctuation ratio); Lower limit of voltage required for voltage calibration = Detected voltage value of current-voltage sensing device during dynamic conduction * (1 - Voltage fluctuation ratio); The voltage fluctuation ratio ranges from 10% to 50%.

4. The dynamic on-resistance testing platform according to claim 1, characterized in that: In step 3, when performing dynamic on-resistance testing, the current and voltage capturing device is used to capture the test current value and / or test voltage value as the test data.

5. The dynamic on-resistance testing platform according to claim 4, characterized in that: In step 4, the test current value is corrected using the current correction coefficient to obtain a corrected current value, and the test voltage value is corrected using the voltage correction coefficient to obtain a corrected voltage value. Then, the corrected dynamic resistance value corresponding to the semiconductor switching device is obtained using the corrected current value and the corrected voltage value.

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