CN114814515A - Short circuit detection circuit and method of SiC MOSFET - Google Patents

Short circuit detection circuit and method of SiC MOSFET Download PDF

Info

Publication number
CN114814515A
CN114814515A CN202210499632.1A CN202210499632A CN114814515A CN 114814515 A CN114814515 A CN 114814515A CN 202210499632 A CN202210499632 A CN 202210499632A CN 114814515 A CN114814515 A CN 114814515A
Authority
CN
China
Prior art keywords
electrically connected
signal
sic mosfet
voltage signal
resistor
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN202210499632.1A
Other languages
Chinese (zh)
Inventor
赵凤俭
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Feicheng Semiconductor Shanghai Co ltd
Original Assignee
Feicheng Semiconductor Shanghai Co ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Feicheng Semiconductor Shanghai Co ltd filed Critical Feicheng Semiconductor Shanghai Co ltd
Priority to CN202210499632.1A priority Critical patent/CN114814515A/en
Publication of CN114814515A publication Critical patent/CN114814515A/en
Pending legal-status Critical Current

Links

Images

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
    • G01R31/26—Testing of individual semiconductor devices
    • G01R31/2601—Apparatus or methods therefor
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
    • G01R31/26—Testing of individual semiconductor devices
    • G01R31/2607—Circuits therefor
    • G01R31/2621—Circuits therefor for testing field effect transistors, i.e. FET's
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
    • G01R31/50—Testing of electric apparatus, lines, cables or components for short-circuits, continuity, leakage current or incorrect line connections
    • G01R31/52—Testing for short-circuits, leakage current or ground faults

Abstract

The technical scheme of the application provides a short circuit detection circuit and a method for a SiC MOSFET, wherein the short circuit detection circuit comprises: the output side logic control module is used for receiving and outputting the driving pulse signal of the SiC MOSFET and is also used for outputting a control signal synchronous with the driving pulse signal; the output stage power amplification circuit is electrically connected with the output side logic control module, is configured to amplify the driving pulse signal and outputs the driving pulse signal to the SiC MOSFET; and the short circuit detection module is electrically connected with the output side logic control module and the drain electrode of the SiC MOSFET, is configured to receive the control signal and obtain a reference voltage signal, simultaneously obtains a drain-source voltage signal of the SiC MOSFET, and outputs a detection result signal to the output side logic control module based on the drain-source voltage signal and the reference voltage signal. The short circuit detection circuit of the technical scheme can be used for carrying out dynamic short circuit monitoring on a circuit where the SiC MOSFET is located.

Description

Short circuit detection circuit and method of SiC MOSFET
Technical Field
The application relates to the technical field of power electronics, in particular to a short circuit detection circuit and method of a SiC MOSFET.
Background
Power electronic power converters play an important role in production and life as an important device for the utilization of electric energy. The core of the power electronic power converter is a power semiconductor device, which largely determines the performance of the power electronic power converter. At present, most power semiconductor devices are made of Si semiconductor materials, the characteristics of which are close to the theoretical limit, and the Si semiconductor materials become the bottleneck of further development of power electronic power converters. Compared with Si power devices, SiC power devices have more excellent characteristics: the SiC power device has higher switching speed, can work at higher junction temperature, and can simultaneously realize high frequency, high voltage and large current. These characteristics can significantly improve the performance of the semiconductor power converter, obtain higher electric energy conversion efficiency, realize higher power density, reduce system cost, and the like.
In the power electronic converter, a control signal sent by a microcontroller belongs to a weak point signal, a power semiconductor device cannot be directly driven, and a driving circuit needs to be arranged between the microcontroller and the power semiconductor device. The driving circuit is mainly used for realizing on-off control of the power semiconductor device after shaping and power amplification of a weak current control signal sent by the microcontroller; when a fault occurs in the power semiconductor device and the circuit in which the power semiconductor device is located, the fault information is also transmitted back to the microcontroller by the driving circuit. Therefore, the driving circuit is a bridge for interaction between the weak current control signal and the strong current power circuit, and the reliability of the driving circuit directly influences the overall reliability of the power electronic converter.
The SiC MOSFET is mainly applied to high-voltage occasions, has high requirement on reliability, and needs short-circuit detection and protection if a circuit in which the SiC MOSFET is arranged is short-circuited to cause serious consequences. At present, a plurality of problems exist when short-circuit protection is carried out by adopting desaturation detection, for example, if the blanking time is short, false operation is easy; if the blanking time is too long, it is difficult to safely shut down within a specified maximum short circuit time. The blanking time is determined by the blanking capacitance value, but the selection of the blanking capacitance value is difficult; after the blanking capacitance value is determined, the blanking capacitance value is also influenced by temperature, and meanwhile, a high-voltage diode in the desaturation detection circuit belongs to a strong interference source.
Disclosure of Invention
The technical problem to be solved by the application is to provide a short circuit detection circuit and a short circuit detection method for a SiC MOSFET, which can monitor a short circuit of a circuit where the SiC MOSFET is located and overcome the existing problem of desaturation detection.
In order to solve the above technical problem, the present application provides a short circuit detection circuit of a SiC MOSFET, including: the output side logic control module is used for receiving and outputting the driving pulse signal of the SiC MOSFET and is also used for outputting a control signal synchronous with the driving pulse signal; the output stage power amplification circuit is electrically connected with the output side logic control module, is configured to amplify the driving pulse signal and outputs the driving pulse signal to the SiC MOSFET; and the short circuit detection module is electrically connected with the output side logic control module and the drain electrode of the SiC MOSFET, is configured to receive the control signal and obtain a reference voltage signal, simultaneously obtains a drain-source voltage signal of the SiC MOSFET, and outputs a detection result signal to the output side logic control module based on the drain-source voltage signal and the reference voltage signal.
In some embodiments of the present application, the short circuit detection module is configured to compare the drain-source voltage signal with the reference voltage signal, when the drain-source voltage signal is greater than the reference voltage signal, the operational amplifier signal is inverted, and the short circuit detection module outputs a short circuit signal to the output side logic control module.
In some embodiments of the present application, the short detection module is further configured to compare the drain-source voltage signal with the reference voltage signal, and when the drain-source voltage signal is less than or equal to the reference voltage signal, the operational amplifier signal does not flip.
In some embodiments of the present application, the short detection module comprises: the comparator comprises a first input end, a second input end and an output end, wherein the output end is electrically connected with the output side logic control module; the drain-source voltage signal source circuit is electrically connected with the first input end; and the reference voltage signal source circuit is electrically connected with the second input end.
In some embodiments of the present application, the drain-source voltage signal source circuit includes: a first end of the fifth resistor is electrically connected with the drain electrode of the SiC MOSFET, and two ends of the fifth resistor are also electrically connected with a second capacitor; a first end of the sixth resistor is electrically connected with a second end of the fifth resistor, and two ends of the sixth resistor are also electrically connected with a third capacitor; a first end of the seventh resistor is electrically connected with a second end of the sixth resistor, a second end of the seventh resistor is electrically connected with the first input end, and two ends of the seventh resistor are also electrically connected with a fourth capacitor; and the first end of the eighth resistor is electrically connected with the first input end, the second end of the eighth resistor is connected with the output side ground, and the two ends of the eighth resistor are also electrically connected with a fifth capacitor.
In some embodiments of the present application, the reference voltage signal source circuit includes: a gate of the third MOS transistor is electrically connected to the output side logic control module, a source of the third MOS transistor is connected to the output side ground, and the third MOS transistor is controlled by the control signal; the anode of the first voltage stabilizing diode is electrically connected with the drain electrode of the third MOS tube; a ninth resistor, a first end of which is electrically connected to the cathode of the first zener diode and a second end of which is electrically connected to the second input terminal; a first end of the sixth capacitor is electrically connected with the second input end, and a second end of the sixth capacitor is connected with the output side ground; and a tenth resistor, wherein a first end of the tenth resistor is electrically connected with the direct-current positive voltage, and a second end of the tenth resistor is electrically connected with the second input end.
In some embodiments of the present application, the short detection circuit further comprises: and the auxiliary detection module is positioned between the Kelvin pin and the source electrode pin of the SiC MOSFET and used for detecting the current change rate of the SiCMOS MOSFET.
In some embodiments of the present application, the auxiliary detection module comprises: the anode of the second diode is connected with the output side ground; an eleventh resistor, a first end of which is electrically connected to the cathode of the second diode, and a second end of which is electrically connected to the source of the SiC MOSFET; a twelfth resistor, a first end of which is electrically connected to the cathode of the second diode; a first end of the seventh capacitor is electrically connected with a second end of the twelfth resistor, and a second end of the seventh capacitor is electrically connected with the source electrode of the SiC MOSFET; and the primary side of the transformer is electrically connected with two ends of the seventh capacitor, one end of the secondary side of the transformer is electrically connected with the output side logic control module, and the other end of the secondary side of the transformer is connected with the output side ground.
In some embodiments of the present application, the output stage power amplifying circuit includes a push-pull driving circuit formed by a PMOS transistor and an NMOS transistor, or includes a push-pull driving circuit formed by an NPN transistor and a PNP transistor.
In some embodiments of the present application, the output stage power amplification circuit comprises: the input end of the amplifier is electrically connected with the output side logic control module, and the amplifier is also electrically connected with a direct current positive voltage, a direct current negative voltage and an output side ground; the source electrode of the PMOS tube is electrically connected with the direct-current voltage, the grid electrode of the PMOS tube is electrically connected with the output end of the amplifier, and the drain electrode of the PMOS tube is electrically connected with the grid electrode of the SiC MOSFET through a third resistor; and the source electrode of the NMOS tube is electrically connected with the direct-current negative voltage, the grid electrode of the NMOS tube is electrically connected with the output end of the amplifier, and the drain electrode of the NMOS tube is electrically connected with the grid electrode of the SiC MOSFET through a first resistor.
In some embodiments of the present application, the short circuit detection circuit further includes an input side logic control module, configured to receive the driving pulse signal of the SiC MOSFET and output the driving pulse signal to the output side logic control module, and the output side logic control module further feeds back a detection result signal to the input side logic control module.
In some embodiments of the present application, a second codec module is electrically connected between the input side logic control module and the output side logic control module, and the second codec module includes: the feedback coding module is electrically connected with the output side logic control module; and the feedback decoding module is in signal isolation with the feedback coding module and is electrically connected with the input side logic control module.
The application also provides a short circuit detection method of the SiC MOSFET, which comprises the following steps: the output side logic control module receives and outputs the driving pulse signal of the SiC MOSFET and is also used for outputting a control signal synchronous with the driving pulse signal; the output stage power amplification circuit amplifies the driving pulse signal and outputs the driving pulse signal to the SiC MOSFET; and the short circuit detection module receives the control signal and obtains a reference voltage signal, obtains a drain-source voltage signal of the SiC MOSFET at the same time, and outputs a detection result signal to the output side logic control module based on the drain-source voltage signal and the reference voltage signal.
In some embodiments of the present application, a method of outputting a detection result signal to the output side logic control module based on the drain-source voltage signal and the reference voltage signal includes: and comparing the drain-source voltage signal with the reference voltage signal, when the drain-source voltage signal is greater than the reference voltage signal, turning over the operational amplifier signal, and outputting a short-circuit signal to the output side logic control module by the short-circuit detection module.
In some embodiments of the present application, the operational amplifier signal does not flip when the drain-source voltage signal is less than the reference voltage signal.
According to the technical scheme, the short circuit detection circuit is provided with the short circuit detection module, and the control signal of the short circuit detection module is synchronous with the driving pulse signal, so that the reference voltage signal has an adjustable characteristic, dynamic detection of the circuit is realized, and the problems that parameters of the existing short circuit detection circuit are difficult to set and other devices are interfered can be solved.
Drawings
The following drawings describe in detail exemplary embodiments disclosed in the present application. Wherein like reference numerals represent similar structures throughout the several views of the drawings. Those of ordinary skill in the art will understand that the present embodiments are non-limiting, exemplary embodiments and that the accompanying drawings are for illustrative and descriptive purposes only and are not intended to limit the scope of the present application, as other embodiments may equally fulfill the inventive intent of the present application. It should be understood that the drawings are not to scale. Wherein:
fig. 1 is a schematic structural diagram of a short circuit detection circuit of a SiC MOSFET according to an embodiment of the present application;
fig. 2 is a schematic structural diagram of another short detection circuit of a SiC MOSFET according to an embodiment of the present application;
FIG. 3 is a change curve of a source-drain voltage signal and a reference voltage signal when a SiC MOSFET is switched from off to on and a circuit in which the SiC MOSFET is in short circuit;
fig. 4 is a schematic structural diagram of a short detection circuit of a further SiC MOSFET according to an embodiment of the present application;
FIG. 5 is a schematic diagram of an output stage power amplifier according to an embodiment of the present disclosure;
fig. 6 is a schematic structural diagram of a short detection circuit of a further SiC MOSFET according to an embodiment of the present application.
Detailed Description
In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings used in the description of the embodiments will be briefly introduced below. It is obvious that the drawings in the following description are only examples or embodiments of the application, from which the application can also be applied to other similar scenarios without inventive effort for a person skilled in the art. Unless otherwise apparent from the context, or otherwise indicated, like reference numbers in the figures refer to the same structure or operation.
It should be understood that "module," "circuit," as used herein, is a method for distinguishing different components, elements, components, portions or assemblies at different levels. However, other words may be substituted by other expressions if they accomplish the same purpose.
The terminology used in the description presented herein is for the purpose of describing particular example embodiments only and is not intended to be limiting. For example, as used herein, the singular forms "a", "an" and "the" may include the plural forms as well, unless the context clearly indicates otherwise. The terms "comprises," "comprising," "includes," and/or "including," when used in this specification, are intended to specify the presence of stated integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. When different components are described in this specification as being associated, they may be in a direct relationship or an indirect relationship. For example, "a and B are connected" may be that a and B are directly connected, or that a and B are indirectly connected through other components.
These and other features disclosed herein, as well as the operation and function of the related elements of structure and the combination of parts and economies of manufacture, may be significantly improved upon consideration of the following description. All of which form a part of the disclosure of this specification, with reference to the accompanying drawings. It is to be expressly understood, however, that the drawings are for the purpose of illustration and description only and are not intended as a definition of the limits of the present disclosure. Flow charts are used herein to illustrate operations performed by systems according to embodiments of the present application. It should be understood that the preceding or following operations are not necessarily performed in the exact order in which they are performed. Rather, the steps may be processed in reverse order or simultaneously. Meanwhile, other operations may be added to the processes, or a certain step or several steps of operations may be removed from the processes.
The following description is presented to enable any person skilled in the art to make and use the present disclosure, and is provided in the context of a particular application and its requirements. Various modifications to the disclosed embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other embodiments and applications without departing from the spirit and scope of the present application. Thus, the present application is not limited to the embodiments shown, but is to be accorded the widest scope consistent with the claims.
At present, short-circuit protection is not arranged in the SiC MOSFET circuit design, and part of the SiC MOSFET circuit design is also provided with the short-circuit protection in application, namely, the protection principle and design of Si IGBT devices are used, and static desaturation detection protection is arranged. Under normal working conditions, the IGBT device works in a saturation region when being switched on, works in a cut-off region when being switched off, and needs to pass through an amplification region in the switching-on and switching-off processes. When the short circuit occurs in the IGBT, the operating point of the IGBT enters the amplification region from the saturation region, i.e., the region with high voltage and large current, which is called desaturation. By sensing the voltage V between the collector and emitter of the IGBT CE Can identify the short circuit of the IGBT and the factThe current approach is generally static desaturation detection protection using diodes.
During detection, the blanking time can be set through the blanking capacitor, so that the SiC MOSFET does not send an error signal before the saturation of the received opening signal. After the blanking capacitance is sized, the tolerance (maximum) and constant current source (minimum) of the internal reference voltage must be known. In addition, considering that the protected SiC MOSFET must be safely turned off within its specified maximum short-circuit time, the identification of desaturation detection, internal processing, and turning off of the SiC MOSFET must be completed within the maximum short-circuit time, so the selection of the size of the blanking capacitor is critical and difficult.
In addition, V DS SAT is measured by determining the voltage V by means of a current source and a high voltage diode DS The high voltage diode has a high junction capacitance and is effective each time the SiC MOSFET is turned on and off, and the displacement current flowing through the high voltage diode is unnecessary and interferes with other electronic devices.
Based on this, the application provides a short circuit detection circuit of SiC MOSFET, can carry out dynamic short circuit monitoring to the circuit that SiC MOSFET belongs to, has solved the difficult problem that sets up of parameter and disturb other devices when short circuit detects at present.
Referring to fig. 1, the short circuit detection circuit of the SiC MOSFET of the embodiment of the present application includes an output side logic control module, an output stage power amplification circuit, and a short circuit detection module, where the output side logic control module is configured to receive and output a driving pulse signal of the SiC MOSFET, and is further configured to output a control signal synchronized with the driving pulse signal, and the control signal is configured to control the short circuit detection module. The output stage power amplification circuit is electrically connected with the output side logic control module, and is configured to amplify the driving pulse signal and output the driving pulse signal to the SiCMOS MOSFET. The short circuit detection module is electrically connected with the output side logic control module and the drain D of the SiC MOSFET, and is configured to receive the control signal and obtain a reference voltage signal, obtain a drain-source voltage signal of the SiC MOSFET at the same time, and output a detection result signal to the output side logic control module based on the drain-source voltage signal and the reference voltage signal.
Specifically, the short circuit detection module may be configured to compare the drain-source voltage signal with the reference voltage signal, and when the drain-source voltage signal is greater than the reference voltage signal, the operational amplifier signal is inverted, and the short circuit detection module outputs a short circuit signal to the output side logic control module. And when the drain-source voltage signal is less than or equal to the reference voltage signal, the operational amplifier signal is not inverted.
Referring to fig. 2, the short detection module 100 may include a comparator, a drain-source voltage signal source circuit, and a reference voltage signal source circuit. The comparator comprises a first input end, a second input end and an output end, wherein the first input end is electrically connected with the drain-source voltage signal source circuit and is used for inputting a source-drain voltage signal V of the SiC MOSFET DS The second input end is electrically connected with the reference voltage signal source circuit and is used for inputting a reference voltage signal V ref And the output end is electrically connected with the output side logic control module and is used for outputting a detection result signal to the output side logic control module.
The drain-source voltage signal source circuit comprises a fifth resistor R5, a sixth resistor R6, a seventh resistor R7 and an eighth resistor R8. The first end of the fifth resistor R5 is electrically connected with the drain D of the SiC MOSFET, the second end of the fifth resistor R5 is electrically connected with the first end of the sixth resistor R6, and the two ends of the fifth resistor R5 are also electrically connected with a second capacitor C2. The second end of the sixth resistor R6 is electrically connected with the first end of the seventh resistor R7, and both ends of the sixth resistor R6 are also electrically connected with a third capacitor C3. The second end of the seventh resistor R7 is electrically connected to the first input end of the comparator, and both ends of the seventh resistor R7 are further electrically connected to a fourth capacitor C4. The first end of the eighth resistor R8 is electrically connected to the first input end of the comparator, the second end of the eighth resistor R8 is connected to the output side GND, and the two ends of the eighth resistor R8 are further electrically connected to a fifth capacitor C5.
The reference voltage signal source circuit may include a third MOS transistor M3, a first zener diode T1, a ninth resistor R9, a sixth capacitor C6, and a tenth resistor R10. The gate of the third MOS transistor M3 is electrically connected to the output-side logic control module, the source of the third MOS transistor M3 is connected to the output-side ground GND, the drain of the third MOS transistor M3 is electrically connected to the anode of the first zener diode T1, and the on-off state of the third MOS transistor is controlled by the control signal output by the output-side logic control module. The first end of the ninth resistor R9 is electrically connected to the cathode of the first zener diode T1, and the second end of the ninth resistor R9 is electrically connected to the second input end of the comparator. The first end of the sixth capacitor C6 is electrically connected to the second input end of the comparator, and the second end of the sixth capacitor C6 is connected to the output side ground GND. The first end of the tenth resistor R10 is electrically connected with the direct-current positive voltage VCC, and the second end of the tenth resistor R10 is electrically connected with the second input end of the comparator.
The embodiment of the application adopts a plurality of resistors connected in series to divide voltage to obtain a drain-source voltage signal V DS And the reference voltage signal V sent by the reference voltage signal source circuit is controlled by the control signal output by the output side logic control module ref While the control signal is synchronous with the drive pulse signal, the reference voltage signal V being on during the turn-on of the SiC MOSFET ref The adjustable characteristic is presented, so that the short circuit detection circuit of the embodiment of the application can realize dynamic detection.
FIG. 3 shows a source-drain voltage signal V when the SiC MOSFET is turned on from off and a short circuit occurs in the circuit DS And a reference voltage signal V ref The change curve of (2). Wherein (a) shows that when the SiC MOSFET is turned off and initially turned on, the third MOS transistor M3 is turned off and the reference voltage signal V is applied ref Maintained at a DC positive voltage VCC, V in the figure T1 Represents the forward voltage, V, of the first zener diode T1 DS-SAT Representing the voltage drop of the SiC MOSFET. When the SiC MOSFET is switched on, the third MOS tube M3 is switched on, and the reference voltage signal V ref From a DC positive voltage VCC to V T1 +V R9 ，V R9 Generally small and essentially negligible. (b) The figure shows that when the SiC MOSFET is in the conducting state, if the circuit in which the SiC MOSFET is located is short-circuited (on-state short-circuit fault occurs at A)) Source drain voltage signal V DS From V DS-SAT Starting to rise when the source-drain voltage signal V DS Greater than the reference voltage signal V ref And when the short circuit occurs, the operational amplifier signal is turned over, and the short circuit signal is reported. (c) The figure shows that when the SiC MOSFET is turned on, if the circuit is short-circuited (short-circuit fault in the turn-on process occurs at B), the source-drain voltage signal V DS Greater than the reference voltage signal V ref And the operational amplifier signal is turned over, and the short circuit signal is reported.
In other embodiments, reasonable series-parallel adjustment of the resistors can be performed on the basis of the short circuit detection module 100 shown in fig. 2, so as to meet the requirement of the magnitude of the resistance in practical use. For example, at least one resistor is connected in series or in parallel with the drain-source voltage signal source circuit, or at least one resistor is connected in series or in parallel with the reference voltage signal source circuit. That is, even if the circuit element is simply adjusted in addition to fig. 2, it is within the scope of the present embodiment as long as the dynamic short detection principle of the present embodiment is adopted.
Referring to fig. 4, the short detection circuit may further include an auxiliary detection module between the kelvin pin K and the source pin of the SiC MOSFET for detecting a current change rate (di/dt) of the SiC MOSFET. The existing driving circuit does not detect the current change rate of the SiC MOSFET, and the SiC MOSFET has larger di/dt under the conditions of normal operation, short-circuit fault, overcurrent fault and the like, so that the embodiment of the application adopts a device in a Kelvin pin packaging form, measures di/dt parameters from parasitic reactance between the Kelvin pin and a source electrode pin, and can be used as an auxiliary criterion for the short-circuit fault or the overcurrent fault.
In some embodiments, the auxiliary detection module 200 includes a second diode Z2, an eleventh resistor R11, a twelfth resistor R12, a seventh capacitor C7 and a transformer, the anode of the second diode Z2 and the kelvin pin are both connected to the output side ground GND, the cathode of the second diode Z2 is electrically connected to a first end of the eleventh resistor R11, and a second end of the eleventh resistor R11 is electrically connected to the source S of the SiC MOSFET. A first end of the twelfth resistor R12 is electrically connected to the cathode of the second diode Z2, a second end of the twelfth resistor R12 is electrically connected to a first end of the seventh capacitor C7, and a second end of the seventh capacitor C7 is electrically connected to the source S of the SiCMOSFET. The primary side of the transformer is electrically connected with two ends of the seventh capacitor C7, one end of the secondary side of the transformer is electrically connected with the output side logic control module, and the other end of the secondary side of the transformer is connected with the output side ground GND.
The output stage power amplifying circuit can be a totem-pole structure built by adopting a power operational amplifier or a discrete element and is used for amplifying the power of a driving signal. By way of example, the output stage power amplifying circuit may be a push-pull driving circuit including a PMOS transistor and an NMOS transistor, or a push-pull driving circuit including NPN and PNP transistors.
Referring to fig. 5, the output stage power amplifying circuit 300 according to the embodiment of the present application is, for example, a push-pull driving circuit including a PMOS transistor and an NMOS transistor. Specifically, the output stage power amplifying circuit 300 may include an amplifier, a PMOS transistor P, NMOS transistor N, and a third resistor R3 as an output resistor, and may further include a resistor R1 as a turn-off resistor. The input end of the amplifier is electrically connected with the output side logic control module, and the amplifier is also electrically connected with a direct current positive voltage VCC, a direct current negative voltage VEE and an output side ground GND. The source electrode of the PMOS tube P is electrically connected with the direct-current voltage VCC, the grid electrode of the PMOS tube P is electrically connected with the output end of the amplifier, and the drain electrode of the PMOS tube P is electrically connected with the grid electrode of the SiC MOSFET through the third resistor R3. The source electrode of the NMOS tube is electrically connected with the direct current negative voltage VEE, the grid electrode of the NMOS tube is electrically connected with the output end of the amplifier, and the NMOS tube is electrically connected with the grid electrode of the SiC MOSFET through a first resistor R1.
The circuit structure of the output side logic control module only needs to be capable of receiving the driving pulse signal of the SiCMOSFET and outputting the driving pulse signal to the output stage power amplifying circuit, and to output the control signal synchronized with the driving pulse signal to the short circuit detection module.
Referring to fig. 6, in some embodiments, the short circuit detection circuit further includes an input side logic control module, configured to receive a driving pulse signal of the SiC MOSFET and output the driving pulse signal to the output side logic control module, and the output side logic control module further feeds back a detection result signal to the input side logic control module. The specific structure of the input side logic control module is not limited, and any circuit structure capable of realizing the above functions may be adopted.
And a second coding and decoding module can be electrically connected between the input side logic control module and the output side logic control module. The second codec module includes: the feedback coding module is electrically connected with the output side logic control module; and the feedback decoding module is in signal isolation with the feedback coding module and is electrically connected with the input side logic control module.
The embodiment of the application also provides a short circuit detection method of the SiC MOSFET, which can be realized by the short circuit detection circuit and can also be realized by other conversion circuits. The short circuit detection method comprises the following steps: the output side logic control module receives and outputs the driving pulse signal of the SiC MOSFET and is also used for outputting a control signal synchronous with the driving pulse signal; the output stage power amplification circuit amplifies the driving pulse signal and outputs the driving pulse signal to the SiCMOS MOSFET; and the short circuit detection module receives the control signal and obtains a reference voltage signal, obtains a drain-source voltage signal of the SiC MOSFET at the same time, and outputs a detection result signal to the output side logic control module based on the drain-source voltage signal and the reference voltage signal.
In some embodiments, the method of outputting a detection result signal to the output side logic control module based on the drain-source voltage signal and the reference voltage signal includes: and comparing the drain-source voltage signal with the reference voltage signal, when the drain-source voltage signal is greater than the reference voltage signal, the operational amplifier signal is turned over, and the short circuit detection module outputs a short circuit signal to the output side logic control module. And when the drain-source voltage signal is smaller than the reference voltage signal, the operational amplifier signal is not turned over.
In view of the above, it will be apparent to those skilled in the art upon reading the present application that the foregoing application content may be presented by way of example only, and may not be limiting. Those skilled in the art will appreciate that the present application is intended to cover various reasonable variations, adaptations, and modifications of the embodiments described herein, although not explicitly described herein. Such alterations, modifications, and variations are intended to be within the spirit and scope of the exemplary embodiments of this application.
It will be further understood that, although the terms first, second, third, etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. Thus, a first element in some embodiments may be termed a second element in other embodiments without departing from the teachings of the present application. The same reference numerals or the same reference characters denote the same elements throughout the specification.

Claims (15)

1. A short detection circuit for a SiC MOSFET, comprising:
the output side logic control module is used for receiving and outputting the driving pulse signal of the SiC MOSFET and is also used for outputting a control signal synchronous with the driving pulse signal;
the output stage power amplification circuit is electrically connected with the output side logic control module, is configured to amplify the driving pulse signal and outputs the driving pulse signal to the SiC MOSFET;
and the short circuit detection module is electrically connected with the output side logic control module and the drain electrode of the SiC MOSFET, is configured to receive the control signal and obtain a reference voltage signal, simultaneously obtains a drain-source voltage signal of the SiC MOSFET, and outputs a detection result signal to the output side logic control module based on the drain-source voltage signal and the reference voltage signal.
2. The short circuit detection circuit of the SiC MOSFET of claim 1, wherein the short circuit detection module is configured to compare the drain-source voltage signal with the reference voltage signal, wherein the operational amplifier signal toggles when the drain-source voltage signal is greater than the reference voltage signal, and wherein the short circuit detection module outputs the short circuit signal to the output side logic control module.
3. The short detection circuit of the SiC MOSFET of claim 2, wherein the short detection module is further configured to compare the drain-source voltage signal to the reference voltage signal, the operational amplifier signal not toggling when the drain-source voltage signal is less than or equal to the reference voltage signal.
4. The short detection circuit of the SiC MOSFET of claim 3, wherein the short detection module comprises:
the comparator comprises a first input end, a second input end and an output end, wherein the output end is electrically connected with the output side logic control module;
the drain-source voltage signal source circuit is electrically connected with the first input end;
and the reference voltage signal source circuit is electrically connected with the second input end.
5. The short detection circuit of the SiC MOSFET of claim 4, wherein said drain-source voltage signal source circuit comprises:
a first end of the fifth resistor is electrically connected with the drain electrode of the SiC MOSFET, and two ends of the fifth resistor are also electrically connected with a second capacitor;
a first end of the sixth resistor is electrically connected with a second end of the fifth resistor, and two ends of the sixth resistor are also electrically connected with a third capacitor;
a first end of the seventh resistor is electrically connected with a second end of the sixth resistor, a second end of the seventh resistor is electrically connected with the first input end, and two ends of the seventh resistor are also electrically connected with a fourth capacitor;
and the first end of the eighth resistor is electrically connected with the first input end, the second end of the eighth resistor is connected with the output side ground, and the two ends of the eighth resistor are also electrically connected with a fifth capacitor.
6. The short circuit detection circuit of the SiC MOSFET of claim 4, wherein the reference voltage signal source circuit comprises:
a gate of the third MOS transistor is electrically connected to the output side logic control module, a source of the third MOS transistor is connected to the output side ground, and the third MOS transistor is controlled by the control signal;
the anode of the first voltage stabilizing diode is electrically connected with the drain electrode of the third MOS tube;
a ninth resistor, a first end of which is electrically connected to the cathode of the first zener diode and a second end of which is electrically connected to the second input terminal;
a first end of the sixth capacitor is electrically connected with the second input end, and a second end of the sixth capacitor is connected with the output side ground;
and a tenth resistor, wherein a first end of the tenth resistor is electrically connected with the direct-current positive voltage, and a second end of the tenth resistor is electrically connected with the second input end.
7. The short circuit detection circuit of the SiC MOSFET of claim 1, further comprising: and the auxiliary detection module is positioned between the Kelvin pin and the source electrode pin of the SiC MOSFET and used for detecting the current change rate of the SiC MOSFET.
8. The short circuit detection circuit of the SiC MOSFET of claim 7, wherein the auxiliary detection module comprises:
the anode of the second diode is connected with the output side ground;
an eleventh resistor, a first end of which is electrically connected to the cathode of the second diode, and a second end of which is electrically connected to the source of the SiC MOSFET;
a twelfth resistor, a first end of the twelfth resistor being electrically connected to the cathode of the second diode;
a first end of the seventh capacitor is electrically connected with a second end of the twelfth resistor, and a second end of the seventh capacitor is electrically connected with the source electrode of the SiC MOSFET;
and the primary side of the transformer is electrically connected with two ends of the seventh capacitor, one end of the secondary side of the transformer is electrically connected with the output side logic control module, and the other end of the secondary side of the transformer is connected with the output side ground.
9. The short circuit detection circuit of the SiC MOSFET as recited in claim 1, wherein the output stage power amplification circuit comprises a push-pull driving circuit formed by a PMOS transistor and an NMOS transistor, or comprises a push-pull driving circuit formed by an NPN transistor and a PNP transistor.
10. The short circuit detection circuit of the SiC MOSFET of claim 9, wherein the output stage power amplification circuit comprises:
the input end of the amplifier is electrically connected with the output side logic control module, and the amplifier is also electrically connected with a direct current positive voltage, a direct current negative voltage and an output side ground;
the source electrode of the PMOS tube is electrically connected with the direct-current voltage, the grid electrode of the PMOS tube is electrically connected with the output end of the amplifier, and the drain electrode of the PMOS tube is electrically connected with the grid electrode of the SiC MOSFET through a third resistor;
and the source electrode of the NMOS tube is electrically connected with the direct-current negative voltage, the grid electrode of the NMOS tube is electrically connected with the output end of the amplifier, and the drain electrode of the NMOS tube is electrically connected with the grid electrode of the SiC MOSFET through a first resistor.
11. The short-circuit detection circuit of the SiC MOSFET of claim 1, further comprising an input-side logic control module for receiving the driving pulse signal of the SiC MOSFET and outputting the driving pulse signal to the output-side logic control module, wherein the output-side logic control module further feeds back a detection result signal to the input-side logic control module.
12. The short circuit detection circuit of SiC MOSFET of claim 11, wherein a second codec module is electrically connected between the input side logic control module and the output side logic control module, and the second codec module comprises:
the feedback coding module is electrically connected with the output side logic control module;
and the feedback decoding module is in signal isolation with the feedback coding module and is electrically connected with the input side logic control module.
13. A short circuit detection method of a SiC MOSFET is characterized by comprising the following steps:
the output side logic control module receives and outputs the driving pulse signal of the SiC MOSFET and is also used for outputting a control signal synchronous with the driving pulse signal;
the output stage power amplification circuit amplifies the driving pulse signal and outputs the driving pulse signal to the SiC MOSFET;
and the short circuit detection module receives the control signal and obtains a reference voltage signal, obtains a drain-source voltage signal of the SiC MOSFET at the same time, and outputs a detection result signal to the output side logic control module based on the drain-source voltage signal and the reference voltage signal.
14. The method of claim 13, wherein the outputting a detection result signal to the output side logic control module based on the drain-source voltage signal and the reference voltage signal comprises: and comparing the drain-source voltage signal with the reference voltage signal, when the drain-source voltage signal is greater than the reference voltage signal, the operational amplifier signal is turned over, and the short circuit detection module outputs a short circuit signal to the output side logic control module.
15. The method of claim 14, wherein the operational amplifier signal is not inverted when the drain-source voltage signal is less than the reference voltage signal.
CN202210499632.1A 2022-05-09 2022-05-09 Short circuit detection circuit and method of SiC MOSFET Pending CN114814515A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202210499632.1A CN114814515A (en) 2022-05-09 2022-05-09 Short circuit detection circuit and method of SiC MOSFET

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202210499632.1A CN114814515A (en) 2022-05-09 2022-05-09 Short circuit detection circuit and method of SiC MOSFET

Publications (1)

Publication Number Publication Date
CN114814515A true CN114814515A (en) 2022-07-29

Family

ID=82514375

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202210499632.1A Pending CN114814515A (en) 2022-05-09 2022-05-09 Short circuit detection circuit and method of SiC MOSFET

Country Status (1)

Country Link
CN (1) CN114814515A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115754656A (en) * 2022-11-23 2023-03-07 东莞光亚智能科技有限公司 Field effect tube damage detection system

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115754656A (en) * 2022-11-23 2023-03-07 东莞光亚智能科技有限公司 Field effect tube damage detection system

Similar Documents

Publication Publication Date Title
CN211930609U (en) SiC MOSFET short-circuit protection circuit based on short-circuit current suppression
US8537515B2 (en) Driving circuit and semiconductor device with the driving circuit
US20110248702A1 (en) Current detection circuit including electrostatic capacitor and rectifying element for increasing gate voltage of protecting mosfet
US9577629B2 (en) Circuit for an active diode and method for operating an active diode
CN102576041A (en) Semiconductor apparatus
US6628532B1 (en) Drive circuit for a voltage-controlled switch
US10084451B2 (en) Level shifter circuit
TW202038559A (en) Cascode compound switch slew rate control
CN113394956A (en) Adjustable soft turn-off and current booster for gate driver
Yin et al. Design considerations and comparison of high-speed gate drivers for Si IGBT and SiC MOSFET modules
CN218386794U (en) Protection circuit of SiC MOSFET
CN111049100B (en) Bootstrap circuit with clamping function
US9568505B2 (en) Semiconductor device
CN114814515A (en) Short circuit detection circuit and method of SiC MOSFET
Zhong et al. 650-V normally-off GaN/SiC cascode device for power switching applications
Basler et al. Function blocks of a highly-integrated all-in-GaN power IC for DC-DC conversion
CN112865767B (en) Circuit for improving response speed of short circuit fault of SiC MOSFET device
Yano et al. Development and verification of protection circuit for hard switching fault of SiC MOSFET by using gate-source voltage and gate charge
CN114915145A (en) Soft turn-off circuit and method of SiC MOSFET
CN111900969B (en) Driving circuit of SiC-MOSFET
US9397207B2 (en) Gated thyristor power device
US20230163759A1 (en) Gate Drive Apparatus and Method Thereof
CN116449249A (en) Silicon carbide MOSFET short circuit detection circuit and device
CN113676029B (en) Active clamp circuit based on IGBT
CN218867915U (en) Protection circuit of SiC MOSFET

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination