Design method of simple HTGB tester

Abstract

The application belongs to the technical field of semiconductor testing devices, and discloses a design method of a simple HTGB tester, which comprises the following steps: main MCU control; the main MCU control is connected with ADC sampling and DAC output; the main MCU control is connected to auxiliary MCU control through connection isolation communication; the main MCU control is connected to temperature / fan control through connection isolation power supply; the auxiliary MCU control is connected with auxiliary power supply and temperature / fan control; the auxiliary MCU control is connected with man-machine interaction touch screen control and DRV1-DRV4 drive management; the isolation power supply is connected with DAC output, ADC sampling and constant current / constant voltage closed loop; the cross current / constant voltage closed loop is connected with DAC output and ADC sampling; the man-machine interaction touch screen control and DRV1-DRV4 drive management are connected with the auxiliary power supply; the auxiliary power supply is connected with optical coupling isolation; and the optical coupling isolation is connected with the cross current / constant voltage closed loop. The application adopts a digital-analog control method, retains the main functions of the HTGB tester while reducing the volume, and has a high cost performance.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of semiconductor testing device, and particularly relates to a design method of a simple HTGB tester. BACKGROUND

[0002] HTGB testing, also known as high-temperature gate bias testing, is one of the most important testing projects of transistors, and can test the voltage resistance, gate reliability and other parameters of Si / SiC / GaN material IGBT / MOSFET / DIODE / BJT power devices, but the general HTGB tester is bulky and expensive, which restricts the development of enterprises.

[0003] Through the above analysis, the problems and defects of the prior art are:

[0004] The general HTGB tester is bulky and expensive, which restricts the development of enterprises. SUMMARY

[0005] In view of the problems existing in the prior art, the present application provides a design method of a simple HTGB tester.

[0006] To solve the above problems, the technical scheme provided by the present application is:

[0007] The present application is implemented as follows: a design method of a simple HTGB tester, comprising:

[0008] Main MCU control;

[0009] The main MCU control connects the ADC sampling and the DAC output, the main MCU control is connected to the auxiliary MCU control through the connection isolation communication, the main MCU control is connected to the temperature / fan control through the connection isolation power supply, the auxiliary MCU control is connected to the auxiliary power supply and the temperature / fan control, the auxiliary MCU control is connected to the man-machine interaction touch screen control and the drive signal interface DRV1-drive signal interface DRV4 drive management, the isolation power supply is connected to the DAC output, the ADC sampling and the constant current / constant voltage closed loop, the cross current / constant voltage closed loop is connected to the DAC output and the ADC sampling, the man-machine interaction touch screen control and the drive signal interface DRV1-drive signal interface DRV4 drive management are connected to the auxiliary power supply, the auxiliary power supply is connected to the optocoupler isolation, and the optocoupler isolation is connected to the cross current / constant voltage closed loop.

[0010] Further, the main MCU collects the output voltage and current, controls the constant current size of the transistor, changes the maximum voltage of the constant current drive, and transmits the parameters to the auxiliary MCU through the isolation communication.

[0011] Further, the auxiliary MCU manages the parameter setting from the man-machine interaction and controls the temperature, fan, drive signal and the like of the whole.

[0012] Further, the input power V1 is a low-voltage isolation input power, the power tube M1, the resistor R1, the triode Q1, the resistor R2, the resistor R3 and the feedback voltage positive interface VFB+ and the feedback voltage negative interface VFB- constitute a linear voltage stabilizing part, the constant current / constant voltage closed loop of the secondary side adjusts the signal size of the feedback voltage positive interface VFB+ and the feedback voltage negative interface VFB- through the optical coupling, controls the conduction depth of the power tube M1 and is used for controlling the high and low of the output voltage.

[0013] Further, the triode Q1, the resistor R2 and the resistor R3 constitute an overcurrent feedback circuit of the linear part, limit the maximum output current of M1, when the output power is large, a plurality of power tubes can be used as linear power units in parallel to increase the output current.

[0014] Further, the power tube M2, the power tube M3, the power tube M4, the power tube M5 and the transformer T1 are an open-loop full-bridge part, an auxiliary MCU outputs a group of complementary PWM signals to a drive management for driving the power tube M2-power tube M5, wherein the power tube M2 and the power tube M4 are switched simultaneously, the power tube M3 and the power tube M5 are switched simultaneously, and the switching frequency is 200KHZ.

[0015] Further, the secondary winding T1-1 and the secondary winding T1-2 are the secondary windings of the transformer T1, the rectifier diode D1-rectifier diode D8 are full-bridge rectifier diodes of the two windings, because the output voltage is high and the frequency is high, the diodes adopt high-voltage silicon carbide diodes, for reducing the loss and improving the reliability.

[0016] Further, the resistor R3-resistor R7 is an output voltage dividing resistor, because the output voltage is high, the voltage dividing resistor needs to be connected in series, the two ends of the resistor R7 obtain an equal proportion output voltage signal, the signal is sent into an ADC for output voltage collection, and the signal is sent into a constant current / constant voltage ring and a VREF-I / -U signal output by a DAC for closed-loop driving an isolation optical coupling, for closed-loop adjustment of the output voltage.

[0017] Further, the transient voltage suppression diode TVS1 and the current sensing resistor RCS2 constitute an output current detection sample, the transient voltage suppression diode TVS1 is used for preventing the voltage at the two ends of the current sensing resistor RCS2 from being too large in the moment of sudden short circuit of the power supply, so as to damage the resistor, the two end signals of the current sensing resistor RCS2 are sent into an ADC for output voltage collection, and the signal is sent into a constant current / constant voltage ring for closed-loop adjustment of the output current.

[0018] Another purpose of the application is to provide a digital-analog control method for realizing the functions of the whole machine.

[0019] Step one: the operational amplifier U1, the resistor R8, the resistor R9 and the capacitor C4 constitute the constant current drive circuit of the power tube M6, the current flowing through the power tube M6 is changed by changing the size of the reference voltage interface VREF1 voltage, and the output signal of the operational amplifier U1 and the signal driving voltage VGS2 of the resistor end of the current limiting resistor RCS1 are introduced.

[0020] Step two: the driving voltage of the power tube M6 is obtained by collecting the difference voltage of the two signals through the ADC, and is finally transmitted to the display screen through isolation communication, so that the driving voltage VGS of the power tube M6 transistor under different currents can be directly seen.

[0021] Step three: the resistor R9 is a resistor with a fuse function, when the power tube M6 is damaged by the measured object, high voltage may exist at the gate of the power tube M6, the safety of the driving circuit is protected by fusing the resistor R9, and the size of the voltage output by the operational amplifier U1 can be used to determine whether the resistor R9 is damaged.

[0022] Step four: the operational amplifier U2, the resistor R10, the resistor R11, the triode Q2, the capacitor C5 and the capacitor C6 constitute a controllable voltage source for supplying power to the operational amplifier U1 constant current operational amplifier, the size of the supply voltage of the operational amplifier U1 is adjusted by adjusting the size of the reference voltage interface VREF2 voltage, and different types of transistor driving are matched.

[0023] In combination with the above technical solutions and the technical problems solved, the technical solutions of the present application have the following advantages and positive effects:

[0024] The present application adopts the method of digital analog control, which retains the main functions of the HTGB tester while reducing the volume, and has high cost performance. BRIEF DESCRIPTION OF DRAWINGS

[0025] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed in the embodiments of the present application will be briefly introduced as follows. Obviously, the drawings described below are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor on the basis of these drawings.

[0026] Fig. 1 It is a simple HTGB tester circuit structure diagram provided by the embodiment of the present application.

[0027] Fig. 2 It is a simple HTGB tester real object diagram provided by the embodiment of the present application. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical scheme and advantages of the present application more clear, the present application is further described in detail below with examples. It should be understood that the specific examples described herein are only used to explain the present application and not to limit the present application.

[0029] In order to make the person skilled in the art fully understand how the present application is specifically implemented, this part is an explanation and description of the examples of the technical scheme of the claims.

[0030] As shown in Figs. 1-2 The present application provides a simple HTGB tester design method, test circuit, comprising:

[0031] The main MCU controls;

[0032] The main MCU controls the ADC sampling and the DAC output, the main MCU controls is connected to the auxiliary MCU control through the connection isolation communication, the main MCU controls is connected to the temperature / fan control through the connection isolation power supply, the auxiliary MCU control is connected to the auxiliary power supply and the temperature / fan control, the auxiliary MCU control is connected to the man-machine interaction touch screen control and the driving signal interface DRV1-driving signal interface DRV4 driving management, the isolation power supply is connected to the DAC output, the ADC sampling and the constant current / constant voltage closed loop, the cross current / constant voltage closed loop is connected to the DAC output and the ADC sampling, the man-machine interaction touch screen control and the driving signal interface DRV1-driving signal interface DRV4 driving management are connected to the auxiliary power supply, the auxiliary power supply is connected to the optocoupler isolation, and the optocoupler isolation is connected to the cross current / constant voltage closed loop.

[0033] The main MCU collects the output voltage and current, controls the transistor constant current size, changes the highest voltage of the constant current drive, and transmits the parameters to the auxiliary MCU through the isolation communication.

[0034] The auxiliary MCU manages the parameter setting from the man-machine interaction and controls the temperature, fan, driving signal and the like of the whole.

[0035] The input power supply V1 is a low-voltage isolation input power supply, the power tube M1, the resistor R1, the triode Q1, the resistor R2, the resistor R3 and the feedback voltage positive interface VFB+ and the feedback voltage negative interface VFB- constitute a linear voltage stabilizing part, the secondary constant current / constant voltage closed loop adjusts the signal size of the feedback voltage positive interface VFB+ and the feedback voltage negative interface VFB- through the optocoupler, controls the conduction depth of the power tube M1, and is used for controlling the high and low of the output voltage.

[0036] The triode Q1, the resistor R2 and the resistor R3 constitute an overcurrent feedback circuit of the linear part, limit the maximum output current of the power tube M1, and when the output power is large, a plurality of power tubes can be used as linear power units in parallel to increase the output current.

[0037] Power tubes M2, M3, M4, and M5, and transformer T1 are open-loop full-bridge parts. The auxiliary MCU outputs a set of complementary PWM signals to the drive management for driving power tubes M2 to M5. Among them, power tubes M2 and M4 are switched at the same time, and power tubes M3 and M5 are switched at the same time because their switching frequency is 200KHZ.

[0038] Secondary winding T1-1 and secondary winding T1-2 are the secondary windings of transformer T1. Rectifier diodes D1 to D8 are full-bridge rectifier diodes of the two windings. Due to the high output voltage and high frequency, the diodes use high-voltage silicon carbide diodes to reduce losses and improve reliability.

[0039] Resistors R3 to R7 are output voltage divider resistors. Because they output high voltage, multiple voltage divider resistors need to be connected in series. The two ends of resistor R7 obtain proportional output voltage signals, which are sent to the ADC for output voltage acquisition. At the same time, the signals are sent to the constant current / constant voltage loop and the VREF-I / -U signal closed-loop drive isolation optocoupler output by the DAC for closed-loop regulation of the output voltage.

[0040] Transient suppressor diode TVS1 and current-sense resistor RCS2 are used for output current detection and sampling. Transient suppressor diode TVS1 prevents excessive voltage across the current-sense resistor RCS2 during a sudden power short, potentially damaging the resistor. The signal from RCS2's terminals is fed into the ADC for output voltage acquisition and into the constant current / constant voltage loop for closed-loop regulation of the output current.

[0041] Another object of the present invention is to provide a digital-analog control method for realizing the functions of the whole machine:

[0042] Step 1: The operational amplifier U1, resistors R8, R9, and capacitor C4 form a constant current drive circuit for the power tube M6. By changing the voltage of the reference voltage interface VREF1, the current flowing through the power tube M6 transistor is changed. At the same time, the output signal of the operational amplifier U1 and the signal drive voltage VGS2 at the resistor end of the current limiting resistor RCS1 are derived.

[0043] Step 2: The drive voltage of the power tube M6 is obtained by collecting the difference voltage of the two signals through the ADC, and finally transmitted to the display screen through isolated communication. The voltage VGS of the power tube M6 transistor at different currents can be directly seen.

[0044] Step 3: Resistor R9 is a resistor with a fuse function. When the power tube M6 is damaged, there may be high voltage on its gate. By fusing the resistor R9, the safety of its driving circuit is protected. At the same time, the voltage output by the operational amplifier U1 can be used to determine whether the resistor R9 is damaged.

[0045] Step four: the operational amplifier U2, resistance R10, resistance R11, triode Q2, capacitor C5, capacitor C6 constitute a controllable voltage source, for constant current operational amplifier U1 power supply, by adjusting the reference voltage interface VREF2 voltage size adjustment operational amplifier U1 power supply voltage size, for matching different types of transistor drive.

[0046] In order to prove the technical scheme of the application of the invention and the technical value, this part is the application of the technical scheme of the claim to the specific product or the related technology.

[0047] The technical principle of the application: after connecting a isolated low-voltage DC source in series with a power tube, the power tube is connected to an open-loop full-bridge circuit, the full-bridge circuit drives a high-frequency transformer for voltage isolation and voltage boosting, the output voltage is adjusted by adjusting the opening depth of the series power tube, and the output voltage and current signals are collected and the DAC output signals controlled by the main MCU are closed-loop, so as to finally control the primary series power tube, realize a program-controlled voltage and current power source. At the same time, a controlled constant current circuit is added to the measured transistor, so that the size of the transistor current can be controlled, and the maximum voltage of the driving transistor can also be adjusted, which is used to drive different types of transistors.

[0048] In the description of the application, unless otherwise specified, the meaning of "a plurality of" is two or more than two; The orientation or positional relationship indicated by the terms "upper", "lower", "left", "right", "inner", "outer", "front end", "rear end", "head", "tail" and the like is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the application and simplifying the description, and does not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, therefore it cannot be understood as a limitation on the application. In addition, the terms "first", "second", "third" and the like are only for the purpose of description, and cannot be understood as indicating or implying relative importance.

[0049] The above is only a specific embodiment of the application, but the protection scope of the application is not limited thereto, any modification, equivalent replacement and improvement made by those skilled in the art within the technical range disclosed by the application, as long as it is within the spirit and principle of the application, should be covered within the protection scope of the application.

Claims

1. A simple HTGB tester, characterized in that: The design method of the simple HTGB tester includes: Main MCU control; The main MCU control is connected to ADC sampling and DAC output. The main MCU control is connected to the auxiliary MCU control through the isolated communication connection. The main MCU control is connected to the temperature / fan control through the isolated power supply. The auxiliary MCU control is connected to the auxiliary power supply and temperature / fan control. The auxiliary MCU control is connected to the human-machine interaction touch screen control and the drive signal interface DRV1-drive signal interface DRV4 drive management. The isolated power supply is connected to the DAC output, ADC sampling and constant current / constant voltage closed loop. The cross-current / constant voltage closed loop connects the DAC output and ADC sampling. The human-machine interaction touch screen control and drive signal interface DRV1-drive signal interface DRV4 drive management are connected to the auxiliary power supply. The auxiliary power supply is connected to the optocoupler isolation. The optocoupler isolation is connected to the cross-current / constant voltage closed loop.

2. The simple HTGB tester according to claim 1, characterized in that: The main MCU collects output voltage and current, controls the constant current of the transistor, changes the maximum voltage of the constant current drive, and transmits the parameters to the auxiliary MCU through isolated communication.

3. The simple HTGB tester according to claim 1, characterized in that: The auxiliary MCU manages the parameter settings from human-computer interaction and controls the overall temperature, fan, and drive signals.

4. The simple HTGB tester according to claim 1, characterized in that: The input power supply V1 is a low-voltage isolated input power supply. The power tube M1, resistor R1, transistor Q1, resistor R2, resistor R3 and the feedback voltage positive interface VFB+ and feedback voltage negative interface VFB- constitute the linear voltage regulation part. The secondary constant current / constant voltage closed loop adjusts the feedback voltage positive interface VFB+ and feedback voltage negative interface VFB- signals through the optocoupler to control the conduction depth of the power tube M1 and thus control the output voltage.

5. The simple HTGB tester according to claim 4, characterized in that: Transistor Q1, resistor R2, and resistor R3 form the overcurrent feedback circuit of the linear part, which limits the maximum output current of the power tube M1. When the output power is large, multiple power tubes can be used as linear power units in parallel to increase the output current.

6. The simple HTGB tester according to claim 1, characterized in that: Power tubes M2, M3, M4, and M5, and transformer T1 form an open-loop full-bridge component. The auxiliary MCU outputs a set of complementary PWM signals to the driver management for driving power tubes M2 to M5. Power tubes M2 and M4 switch simultaneously, and power tubes M3 and M5 switch simultaneously, because their switching frequency is 200 kHz.

7. The simple HTGB tester according to claim 1, characterized in that: Secondary winding T1-1 and secondary winding T1-2 are the secondary windings of transformer T1. Rectifier diodes D1 to D8 are full-bridge rectifier diodes of the two windings. Due to the high output voltage and high frequency, the diodes use high-voltage silicon carbide diodes to reduce losses and improve reliability.

8. The simple HTGB tester according to claim 1, characterized in that: Resistors R3-R7 are output voltage divider resistors. Because they output high voltage, multiple voltage divider resistors need to be connected in series. Resistor R7 and resistor 2 receive a proportional output voltage signal, which is fed into the ADC for output voltage acquisition. At the same time, the signal is fed into the constant current / constant voltage loop and the VREF-I / -U signal closed-loop drive isolation optocoupler output by the DAC for closed-loop regulation of the output voltage.

9. The simple HTGB tester according to claim 1, characterized in that: The transient suppression diode TVS1 and the current-sense resistor RCS2 are composed of output current detection and sampling. The transient suppression diode TVS1 is used to prevent the voltage at the two terminals of the current-sense resistor RCS2 from being too large when the power supply is suddenly short-circuited, thereby damaging the resistor; the signal at the two terminals of the current-sense resistor RCS2 is sent to the ADC for output voltage acquisition, and at the same time the signal is sent to the constant current / constant voltage loop for closed-loop regulation of the output current.

10. The simple HTGB tester according to claim 1, characterized in that: Digital-analog control method to realize simple HTGB tester function: Step 1: The op amp U1, resistors R8, R9, and capacitor C4 form a constant current drive circuit for the power tube M6. By changing the voltage of the reference voltage interface VREF1, the current flowing through the power tube M6 transistor is changed. At the same time, the output signal of the op amp U1 and the signal drive voltage VGS2 at the resistor end of the current limiting resistor RCS1 are derived. Step 2: The ADC collects the difference voltage between the two signals to obtain the driving voltage of the power tube M6, and finally transmits it to the display screen through isolated communication. The voltage VGS of the power tube M6 transistor at different currents can be directly seen; Step 3: Resistor R9 is a resistor with a fuse function. When the power tube M6 is damaged, its gate may have high voltage. By fusing resistor R9, the safety of its driving circuit is protected. At the same time, the voltage output by the op amp U1 can be used to determine whether resistor R9 is damaged. Step 4: Op amp U2, resistor R10, resistor R11, transistor Q2, capacitor C5, and capacitor C6 form a controllable voltage source to power the constant current op amp U1. The supply voltage of op amp U1 can be adjusted by adjusting the voltage of the reference voltage interface VREF2 to match different types of transistor drivers.

Images