Semi-automatic middle test bench for IGBT module and test method

Abstract

The invention relates to the field of IGBT module testing, and provides a semi-automatic middle testing table for an IGBT module and a testing method. The longitudinal module is arranged on the base, and the output end of the longitudinal module moves back and forth in the first direction; the transverse module is arranged on the base through a support, the output end of the transverse module moves back and forth in the second direction, and the second direction and the first direction are perpendicular to each other and both parallel to the horizontal plane; the vertical module is arranged at the output end of the transverse module, the output end of the vertical module moves back and forth in the third direction, and the third direction is perpendicular to the first direction and the second direction; the mounting box is arranged at the output end of the vertical module; the mounting plate is detachably arranged on the lower surface of the mounting box; a plurality of test pins, which can be in contact with a plurality of pins on the IGBT module to be tested; and a control module. According to the invention, a plurality of parameters of the IGBT module can be tested.

Description

Technical Field

[0001] The present invention relates to the field of IGBT module testing, and in particular to a semi-automatic test bench and a test method for an IGBT module. Background Art

[0002] When testing existing IGBT models, one device can often only test one data. Different devices are required when testing different parameters, and different testing devices are also required when testing different IGBT modules, which increases production costs. Summary of the invention

[0003] The main purpose of the present invention is to provide a semi-automatic test bench and a test method for an IGBT module, so as to solve the above technical problems.

[0004] In order to achieve the above objectives, the technical solution adopted by the present invention is: a semi-automatic test bench for IGBT modules, comprising: Base; A longitudinal module is arranged on the base, and an output end of the longitudinal module moves back and forth along a first direction; A transverse module is arranged on the base through a bracket, and an output end of the transverse module moves back and forth along a second direction, and the second direction is perpendicular to the first direction and parallel to the horizontal plane; A vertical module is arranged on the output end of the horizontal module, and the output end of the vertical module moves back and forth along a third direction, wherein the third direction is perpendicular to the first direction and the second direction; A mounting box is arranged on the output end of the vertical module; A mounting plate, detachably disposed on the lower surface of the mounting box; There are multiple test pins, which are vertically arranged on the mounting plate according to a predetermined layout. Through the movement of the longitudinal module, the transverse module and the vertical module, the multiple test pins can contact multiple pins on the IGBT module to be tested; The control module can selectively control the electrical connection, on-off condition and applied current or voltage of the pin, and then judge the quality of the IGBT module through the feedback signal. The control module includes a first terminal, a second terminal and a third terminal.

[0005] Preferably, there are a plurality of mounting boards, each of which is provided with a pin layout corresponding to a different IGBT module.

[0006] The present invention also provides a test method for an IGBT module, using the above-mentioned test bench, wherein the IGBT module includes an upper bridge and a lower bridge, the upper bridge and the lower bridge have the same structure, both include an IGBT, the IGBT has a built-in diode, one end of the diode is connected to the drain D of the IGBT, the other end is connected to the source S, and the diode is turned on in the direction from the source S to the drain D, the drain D of the lower bridge is connected to the first pin, the source S of the lower bridge is connected to the second pin and the seventh pin, the gate G of the lower bridge is connected to the sixth pin, the drain D of the upper bridge is connected to the third pin, the source of the upper bridge is connected to the first pin, and the gate G of the upper bridge is connected to the fourth pin; The testing method specifically comprises the following steps: Step 1: Select a test pin corresponding to the pin layout on the IGBT module; Step 2: Move the longitudinal module, the transverse module and the vertical module to make the test pin contact with the corresponding first pin to the seventh pin; Step 3: The control module controls the states of the first pin to the seventh pin to implement the test of the IGBT module.

[0007] Preferably, the test method is used to test Vth, and the step three specifically includes the following steps: Step 31: Test the upper bridge, including the following steps: Step 311: The control module controls the first terminal to be electrically connected to the fourth pin, the second terminal to be electrically connected to the third pin, and the third terminal to be electrically connected to the first pin and the fifth pin; Step 312: The control module short-circuits the first wiring terminal and the second wiring terminal; Step 313: The control module outputs a voltage between the first terminal and the third terminal to the gate G and the source S of the upper bridge and adjusts the voltage so that a current of 1 mA is present between the gate G and the source S of the upper bridge. At this time, the voltage value between the gate G and the source S is the threshold voltage Vth. Step 314: Compare the obtained threshold voltage Vth with the theoretical value to determine whether there is a problem with the upper bridge; Step 32: Go down the bridge for testing, which specifically includes the following steps: Step 321, connecting the first terminal to the sixth pin, connecting the second terminal to the first pin and the fifth pin, and connecting the third terminal to the second pin and the seventh pin; Step 322, the control module short-circuits the first terminal and the second terminal, outputs voltage to the first terminal and the third terminal, and adjusts the voltage so that a current of 1 mA exists between the gate G and the source S of the lower bridge. At this time, the voltage value between the gate G and the source S is the threshold voltage Vth; Step 323: Compare the obtained threshold voltage Vth with the theoretical value to determine whether there is a problem with the upper bridge.

[0008] Preferably, the test method is used to test Iges, and specifically comprises the following steps: Step 33: Test the upper bridge, including the following steps: Step 331, connecting the first terminal of the control module to the fourth pin, connecting the second terminal to the third pin, and electrically connecting the third terminal to the first pin and the fifth pin; Step 332: The control module controls the second terminal and the third terminal to be short-circuited, and outputs a 20V voltage between the gate G and the source S of the upper bridge through the first terminal and the third terminal; Step 333: monitor the current between the gate G and the source S of the upper bridge, and determine whether there is leakage between the gate G and the source S according to the magnitude of the current; Step 34: testing the lower bridge, specifically including the following steps: Step 341: The control module connects the first terminal to the sixth pin, connects the second terminal to the first pin and the fifth pin, and connects the third terminal to the second pin and the seventh pin; Step 342: The control module controls the second terminal and the third terminal to be short-circuited, and outputs a 20V voltage between the gate G and the source S of the upper bridge through the first terminal and the third terminal; Step 343: monitor the current between the gate G and the source S of the upper bridge, and determine whether there is leakage between the gate G and the source S according to the magnitude of the current.

[0009] Preferably, the testing method is used to test Ices, and specifically comprises the following steps: Step 35: Test the upper bridge, including the following steps: Step 351, connecting the first terminal of the control module to the fourth pin, connecting the second terminal of the control module to the third pin, and electrically connecting the third terminal to the first pin and the fifth pin; Step 352: The control module controls the first terminal and the third terminal to be short-circuited, and applies a voltage of 600V between the drain D and the source S of the upper bridge through the second terminal and the third terminal; Step 353: monitor the current between the drain electrode D and the source electrode S, and determine whether leakage occurs between the drain electrode D and the source electrode S according to the magnitude of the current; Step 36: Test the lower bridge, specifically including the following steps: Step 361, connecting the first terminal to the sixth pin, connecting the second terminal to the first pin and the fifth pin, and connecting the third terminal to the second pin and the seventh pin; Step 362: The control module controls the first terminal and the third terminal to be short-circuited, and applies a voltage of 600V between the D pole and the S pole of the upper bridge through the second terminal and the third terminal; Step 363: monitor the current between the drain electrode D and the source electrode S, and determine whether leakage occurs between the drain electrode D and the source electrode S based on the magnitude of the current.

[0010] Compared with the prior art, the present invention has the following beneficial effects: The test bench and the test method of the present invention can realize the test of multiple parameters of the IGBT module, and during the test, it is only necessary to contact the test needle with the pin of the IGBT module at the beginning. There is no need to move it when testing multiple parameters subsequently, and it is only necessary to change the state of the circuit; and the test bench can realize the test of different IGBT modules, and it is only necessary to replace the mounting plate and the test needle. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 This is the circuit diagram in the IGBT module; Figure 2 This is a structural diagram of a semi-automatic test bench for IGBT modules; Figure 3 This is a structural diagram from another angle of the semi-automatic center test bench for IGBT modules; Figure 4 yes Figure 3 The enlarged view of point A in the middle; Figure 5 It is a schematic diagram of the connection between each pin and the three terminals; Figure 6 This is a connection diagram of the three terminals. DETAILED DESCRIPTION

[0012] The following description is used to disclose the present invention so that those skilled in the art can implement the present invention. The preferred embodiments described below are only examples, and those skilled in the art may think of other obvious variations. Example

[0013] like Figure 2-4As shown, a semi-automatic test bench for an IGBT module comprises a base 101, a longitudinal module 104 arranged on the base 101, a transverse module 103 arranged on the base 101 through a bracket 102, a vertical module 105 arranged on the output end of the transverse module 103, a mounting box 106 arranged on the output end of the vertical module 105, a mounting plate 108 arranged on the lower surface of the mounting box 104, a plurality of test pins 107 arranged below the mounting plate 108, a support plate 109 arranged on the output end of the longitudinal module 104, and a tool 110 placed on the support plate 109, wherein the output end of the longitudinal module 104 The moving direction of the output end, the moving direction of the output end of the horizontal module 103 and the moving direction of the output end of the vertical module 105 are perpendicular to each other, and the moving direction of the output end of the longitudinal module 104 and the moving direction of the output end of the horizontal module 103 are both horizontal. The horizontal module 103 and the longitudinal module 104 are both located directly above the support plate 109. The test pin 107 is conductive, and the test pin 107 is electrically connected to the control module through a wire. When the test pin 107 moves downward and contacts the test point on the IGBT module on the tooling 110, the control module can determine whether there is a problem with the IGBT module according to the change of the electrical signal. Preferably, the mounting plate 108 is detachably mounted on the lower surface of the mounting box 104. In practice, a plurality of mounting plates 108 are provided, and different mounting plates 108 are provided with a plurality of test pins 107 in different arrangements to correspond to different IGBT modules to be tested. Different IGBT modules have different test points. When testing different IGBT modules, only the corresponding mounting plate 108 needs to be replaced. Example

[0014] This embodiment is a method for testing the threshold voltage (Vth) of an IGBT module using the intermediate test bench in the first embodiment. The IGBT module includes two IGBTs, each IGBT has a built-in diode, one end of the diode is connected to the drain D of the IGBT, and the other end is connected to the source S, and the diode is turned on in the direction from the source S to the drain D. For the convenience of description, the two IGBTs are respectively referred to as an upper bridge and a lower bridge, the drain D of the lower bridge is connected to the first pin 1, the source S of the lower bridge is connected to the second pin 2 and the seventh pin 7, the gate G of the lower bridge is connected to the sixth pin 6, the drain D of the upper bridge is connected to the third pin 3, the source S of the upper bridge is connected to the first pin 1, and the gate G of the upper bridge is connected to the fourth pin 4. During the test, the arrangement of the corresponding test pins 107 is selected according to the type of the IGBT module. The IGBT module is placed on the tooling 110, and the control module controls the relative movement of the horizontal module 103 and the longitudinal module 4, so that the test needle 107 moves to the top of the test point corresponding to the IGBT module, and the control module controls the vertical module 105 to move downward, so that the test needle 107 contacts the corresponding test point, which is the above-mentioned pin. In practice, the upper bridge and the lower bridge are tested separately during the test. The connection end of the control module has three terminals, namely the first terminal, the second terminal and the third terminal, which correspond to the gate G, the drain D and the source S of the IGBT respectively. During the test, the test needle 107 contacts the pins on the upper bridge and the lower bridge at the same time, and the connection between the pins and the three poles of the control module can be achieved by only controlling the conduction or closing of the circuit.

[0015] When testing the upper bridge, the control module controls the first terminal to be electrically connected to the fourth pin 4, the second terminal to be electrically connected to the third pin 3, and the third terminal to be electrically connected to the first pin 1 and the fifth pin 5. Then the control module short-circuits the first terminal and the second terminal, outputs voltage between the G pole and the S pole of the upper bridge through the first terminal and the third terminal, and adjusts the voltage so that there is a 1mA current between the G pole and the S pole of the upper bridge. The voltage value is the threshold voltage vth, and whether there is a problem with the upper bridge is determined based on the obtained threshold voltage vth.

[0016] When testing the lower bridge, the first terminal is connected to the sixth pin 6, the second terminal is connected to the first pin 1 and the fifth pin 5, and the third terminal is connected to the second pin 2 and the seventh pin 7. Then the control module short-circuits the first terminal and the second terminal, outputs voltage to the first terminal and the third terminal, and adjusts the voltage so that there is a 1mA current between the G pole and the S pole of the lower bridge. The voltage at this time is the threshold voltage vth. Whether there is a problem with the upper bridge is determined based on the obtained threshold voltage vth.

[0017] In actual testing, the number of test pins 107 is the same as the number of pins on the IGBT module, that is, there are seven in this embodiment. The test pin 107 contacts seven pins at the same time, and only the circuit in the control module needs to realize the connection between the third terminal and different pins. Example

[0018] The gate-emitter leakage current (Iges) is tested using the test bench of Example 1, and the tested IGBT module is the same as that of Example 2. When testing the upper bridge, the first terminal of the control module is connected to the fourth pin 4, the second terminal of the control module is connected to the third pin 3, and the third terminal is electrically connected to the first pin 1 and the fifth pin 5. Then the control module controls the second terminal and the third terminal to be short-circuited, and outputs a 20V voltage between the G pole and the S pole of the upper bridge through the first terminal and the third terminal, monitors the current between the G pole and the S pole of the upper bridge, and determines whether there is leakage between the G pole and the S pole by the magnitude of the current.

[0019] When testing the lower bridge, the first terminal is connected to the sixth pin 6, the second terminal is connected to the first pin 1 and the fifth pin 5, and the third terminal is connected to the second pin 2 and the seventh pin 7. Then the control module controls the second terminal and the third terminal to short-circuit, and outputs a 20V voltage between the G pole and the S pole of the upper bridge through the first terminal and the third terminal. The current between the G pole and the S pole of the upper bridge is monitored, and whether there is leakage between the G pole and the S pole is determined by the magnitude of the current. Example

[0020] The Ices of the IGBT module is tested using the test bench of Example 1, and the IGBT module is the same as that of Example 1. When testing the upper bridge, the first terminal of the control module is connected to the fourth pin 4, the second terminal of the control module is connected to the third pin 3, and the third terminal is electrically connected to the first pin 1 and the fifth pin 5. Then the control module controls the first terminal and the third terminal to be short-circuited, and a voltage of 600V is applied between the D pole and the S pole of the upper bridge through the second terminal and the third terminal to monitor whether leakage occurs between the D pole and the S pole.

[0021] When testing the lower bridge, the first terminal is connected to the sixth pin 6, the second terminal is connected to the first pin 1 and the fifth pin 5, and the third terminal is connected to the second pin 2 and the seventh pin 7. Then the control module controls the first terminal and the third terminal to short-circuit, and a 600V voltage is applied between the D pole and the S pole of the upper bridge through the second terminal and the third terminal to monitor whether leakage occurs between the D pole and the S pole.

[0022] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions only describe the principles of the present invention. The present invention may be subject to various changes and improvements without departing from the spirit and scope of the present invention. These changes and improvements fall within the scope of the present invention. The scope of protection claimed by the present invention is defined by the attached claims and their equivalents.

Claims

1. A semi-automatic test bench for IGBT modules, characterized in that: include: Base; A longitudinal module is arranged on the base, and an output end of the longitudinal module moves back and forth along a first direction; A transverse module is arranged on the base through a bracket, and an output end of the transverse module moves back and forth along a second direction, and the second direction is perpendicular to the first direction and parallel to the horizontal plane; A vertical module is arranged on the output end of the horizontal module, and the output end of the vertical module moves back and forth along a third direction, wherein the third direction is perpendicular to the first direction and the second direction; A mounting box is arranged on the output end of the vertical module; A mounting plate, detachably disposed on the lower surface of the mounting box; There are multiple test pins, which are vertically arranged on the mounting plate according to a predetermined layout. Through the movement of the longitudinal module, the transverse module and the vertical module, the multiple test pins can contact multiple pins on the IGBT module to be tested; The control module can selectively control the electrical connection, on-off condition and applied current or voltage of the pin, and then judge the quality of the IGBT module through the feedback signal. The control module includes a first terminal, a second terminal and a third terminal.

2. A semi-automatic test bench for IGBT modules according to claim 1, characterized in that: There are multiple mounting plates, and each mounting plate is provided with a pin layout corresponding to a different IGBT module.

3. A method for testing an IGBT module, using a semi-automatic test bench for an IGBT module as claimed in claim 2, wherein the IGBT module comprises an upper bridge and a lower bridge, the upper bridge and the lower bridge have the same structure, both comprise an IGBT, the IGBT has a built-in diode, one end of the diode is connected to the drain D of the IGBT, the other end is connected to the source S, and the diode is turned on in a direction from the source S to the drain D, the drain D of the lower bridge is connected to the first pin, the source S of the lower bridge is connected to the second pin and the seventh pin, the gate G of the lower bridge is connected to the sixth pin, the drain D of the upper bridge is connected to the third pin, the source of the upper bridge is connected to the first pin, and the gate G of the upper bridge is connected to the fourth pin; characterized in that The testing method specifically comprises the following steps: Step 1: Select a test pin corresponding to the pin layout on the IGBT module; Step 2: Move the longitudinal module, the transverse module and the vertical module to make the test pin contact with the corresponding first pin to the seventh pin; Step 3: The control module controls the circuit state of the first pin to the seventh pin to implement the test of the IGBT module.

4. The IGBT module testing method according to claim 3, characterized in that: The test method is used to test Vth, and the step three specifically includes the following steps: Step 31: Test the upper bridge, including the following steps: Step 311: The control module controls the first terminal to be electrically connected to the fourth pin, the second terminal to be electrically connected to the third pin, and the third terminal to be electrically connected to the first pin and the fifth pin; Step 312: The control module short-circuits the first wiring terminal and the second wiring terminal; Step 313: The control module outputs a voltage between the first terminal and the third terminal to the gate G and the source S of the upper bridge and adjusts the voltage so that a current of 1 mA is present between the gate G and the source S of the upper bridge. At this time, the voltage value between the gate G and the source S is the threshold voltage Vth. Step 314: Compare the obtained threshold voltage Vth with the theoretical value to determine whether there is a problem with the upper bridge; Step 32: Go down the bridge for testing, which specifically includes the following steps: Step 321, connecting the first terminal to the sixth pin, connecting the second terminal to the first pin and the fifth pin, and connecting the third terminal to the second pin and the seventh pin; Step 322, the control module short-circuits the first terminal and the second terminal, outputs voltage to the first terminal and the third terminal, and adjusts the voltage so that a current of 1 mA exists between the gate G and the source S of the lower bridge. At this time, the voltage value between the gate G and the source S is the threshold voltage Vth; Step 323: Compare the obtained threshold voltage Vth with the theoretical value to determine whether there is a problem with the upper bridge.

5. The IGBT module testing method according to claim 3, characterized in that: The test method is used to test Iges, and specifically comprises the following steps: Step 33: Test the upper bridge, specifically including the following steps: Step 331, connecting the first terminal of the control module to the fourth pin, connecting the second terminal to the third pin, and electrically connecting the third terminal to the first pin and the fifth pin; Step 332: The control module controls the second terminal and the third terminal to be short-circuited, and outputs a 20V voltage between the gate G and the source S of the upper bridge through the first terminal and the third terminal; Step 333: monitor the current between the gate G and the source S of the upper bridge, and determine whether there is leakage between the gate G and the source S according to the magnitude of the current; Step 34: testing the lower bridge, specifically including the following steps: Step 341: The control module connects the first terminal to the sixth pin, connects the second terminal to the first pin and the fifth pin, and connects the third terminal to the second pin and the seventh pin; Step 342: The control module controls the second terminal and the third terminal to be short-circuited, and outputs a 20V voltage between the gate G and the source S of the upper bridge through the first terminal and the third terminal; Step 343: monitor the current between the gate G and the source S of the upper bridge, and determine whether there is leakage between the gate G and the source S according to the magnitude of the current.

6. The IGBT module testing method according to claim 3, characterized in that: The test method is used to test Ices, and specifically comprises the following steps: Step 35: Test the upper bridge, including the following steps: Step 351, connecting the first terminal of the control module to the fourth pin, connecting the second terminal of the control module to the third pin, and electrically connecting the third terminal to the first pin and the fifth pin; Step 352: The control module controls the first terminal and the third terminal to be short-circuited, and applies a voltage of 600V between the drain D and the source S of the upper bridge through the second terminal and the third terminal; Step 353: monitor the current between the drain electrode D and the source electrode S, and determine whether leakage occurs between the drain electrode D and the source electrode S according to the magnitude of the current; Step 36: Test the lower bridge, specifically including the following steps: Step 361, connecting the first terminal to the sixth pin, connecting the second terminal to the first pin and the fifth pin, and connecting the third terminal to the second pin and the seventh pin; Step 362: The control module controls the first terminal and the third terminal to be short-circuited, and applies a voltage of 600V between the drain D and the source S of the upper bridge through the second terminal and the third terminal; Step 363: monitor the current between the drain electrode D and the source electrode S, and determine whether leakage occurs between the drain electrode D and the source electrode S based on the magnitude of the current.

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