Intelligent power module and electronic equipment

Abstract

The present application discloses an intelligent power module and an electronic device, the intelligent power module includes a high-voltage integrated circuit chip, at least one upper bridge IGBT and at least one lower bridge IGBT, the bonding wire of the lower bridge IGBT has a parasitic resistance, the high-voltage integrated circuit chip includes an overcurrent protection unit, the overcurrent protection unit obtains the saturation voltage between the collector and the emitter of the upper bridge IGBT, and obtains the voltage generated by the lower bridge IGBT current passing through the parasitic resistance to monitor the working state of the upper bridge IGBT and the lower bridge IGBT. The present application improves the detection reliability by integrating the overcurrent protection unit into the high-voltage integrated circuit chip, and the overcurrent protection unit performs overcurrent detection protection on the upper bridge IGBT and the lower bridge IGBT at the same time. At the same time, the overcurrent protection unit uses the parasitic resistance of the bonding wire of the lower bridge IGBT itself for sampling, and does not need to set an additional sampling resistor for sampling, thereby reducing the parasitic inductance of the detection circuit.

Description

Technical Field

[0001] The present application relates to the technical field of intelligent power module fault detection, and in particular to an intelligent power module and an electronic device. Background Art

[0002] Intelligent Power Module (IPM) is an advanced power switching device. It is essentially a module that integrates power devices and their drive circuit chips. One of the important functions of the intelligent power module is overcurrent protection to prevent high-power MOSFET or IGBT devices from being damaged due to excessive current.

[0003] In the prior art, a sampling resistor Rs is usually set outside the intelligent power module. The sampling resistor Rs is connected in series with the bottom end (U-, V-, W-) of the three-phase bridge arm. Voltage sampling is performed through the sampling resistor Rs to detect the short-circuit state of the intelligent power module. Summary of the invention

[0004] The present application at least provides an intelligent power module and an electronic device to implement overcurrent detection of the upper bridge IGBT and the lower bridge IGBT, thereby improving detection reliability.

[0005] In a first aspect, the present application provides an intelligent power module, which includes a high-voltage integrated circuit chip, at least one upper bridge IGBT and at least one lower bridge IGBT, the bonding wire of the lower bridge IGBT has a parasitic resistance, the high-voltage integrated circuit chip includes an overcurrent protection unit,

[0006] The overcurrent protection unit obtains the saturation voltage between the collector and emitter of the upper bridge IGBT, and obtains the voltage generated by the lower bridge IGBT current passing through the parasitic resistance, so as to monitor the working status of the upper bridge IGBT and the lower bridge IGBT.

[0007] Optionally, the overcurrent protection unit includes a first overcurrent protection circuit, which obtains a saturation voltage and controls a working state of the upper bridge IGBT based on the saturation voltage and a reference voltage.

[0008] Optionally, the first overcurrent protection circuit includes a comparator, a first detection circuit and a voltage source;

[0009] The first input terminal of the comparator is connected to the collector of the upper bridge IGBT through a first detection circuit, and the first detection circuit obtains a first detection voltage based on the saturation voltage;

[0010] The second input terminal of the comparator is connected to one end of the voltage source, the other end of the voltage source is connected to the ground voltage, and the second input terminal of the comparator obtains a reference voltage through the voltage source.

[0011] Optionally, the first overcurrent protection circuit further includes a current source, and the first detection circuit includes:

[0012] A first MOS tube, a first end of which is connected to the collector of the upper bridge IGBT, and a control end of the first MOS tube is connected to the second end of the first MOS tube;

[0013] A first resistor has one end connected to the second end of the first MOS tube and the other end connected to the first input end of the comparator; a current source is connected to the first input end of the comparator and is used to control the conduction of the first MOS tube.

[0014] Optionally, the first detection voltage is the sum of a saturation voltage drop, a conduction voltage drop of the first MOS tube and a first voltage, and the first voltage is a voltage generated by the first resistor according to a current flowing through the first resistor generated by a current source.

[0015] Optionally, the first overcurrent protection circuit also includes a second detection circuit, the second detection circuit includes a second MOS tube, the first end of the second MOS tube is connected to the first input end of the comparator, the second end of the second MOS tube is connected to the second input end of the comparator, and the second MOS tube is used to control the voltage of the first input end of the comparator.

[0016] Optionally, the gate of the upper bridge IGBT receives the second control signal, the gate of the second MOS tube receives the third control signal, and the phases of the first control signal and the second control signal are set oppositely.

[0017] Optionally, the overcurrent protection unit includes a second overcurrent protection circuit, and the second overcurrent protection circuit obtains a second detection voltage based on an operating current of a parasitic resistance of the bonding wire to monitor an operating state of the lower bridge IGBT.

[0018] Optionally, the intelligent power module also includes a ground wire, the emitter of the lower bridge IGBT is connected to the ground wire through a bonding wire, and the second overcurrent protection circuit is connected to the emitter of the lower bridge IGBT to obtain a second detection voltage based on the working current flowing through the bonding wire.

[0019] Optionally, the intelligent power module further includes a fast recovery diode and a ground wire, the bonding wire includes a first bonding wire and a second bonding wire, the emitter of the lower bridge IGBT is connected to the anode of the fast recovery diode through the first bonding wire, and the anode of the fast recovery diode is connected to the ground wire through the second bonding wire, so that the emitter of the lower bridge IGBT is connected to the ground wire;

[0020] The second overcurrent protection circuit is connected to the emitter of the lower bridge IGBT, and obtains a second detection voltage according to the working current flowing through the first bonding wire and the second bonding wire.

[0021] Optionally, the high-voltage integrated circuit chip includes an ITRIP port, and the second overcurrent protection circuit is detected through the ITRIP port.

[0022] A second aspect of the present application provides an electronic device, comprising the intelligent power module as described above.

[0023] The beneficial effects of the present application are as follows: Different from the prior art, the present application improves the detection reliability of the intelligent power module by integrating the overcurrent protection unit into the high-voltage integrated circuit chip, and the overcurrent protection unit performs overcurrent detection protection on both the upper bridge IGBT and the lower bridge IGBT. At the same time, the overcurrent protection unit uses the parasitic resistance of the bonding wire of the lower bridge IGBT for sampling, and does not need to set up an additional sampling resistor for sampling, thereby reducing the parasitic inductance of the detection circuit and preventing the parasitic inductance from causing detection signal noise, resulting in false triggering of the overcurrent protection.

[0024] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative work, among which:

[0026] Figure 1 is a schematic diagram of an equivalent circuit of an embodiment of the intelligent power module of the present application;

[0027] Figure 2 is a circuit diagram of an embodiment of a first overcurrent protection circuit of the present application;

[0028] Figure 3 is a circuit diagram of another embodiment of the first overcurrent protection circuit of the present application;

[0029] Figure 4 is a logic schematic diagram of the first overcurrent protection circuit of the present application;

[0030] Figure 5 This is a structural schematic diagram of an embodiment of a lower bridge IGBT bonding wire of the present application;

[0031] Figure 6 This is a schematic diagram of the structure of another embodiment of the lower bridge IGBT bonding wire of the present application;

[0032] Figure 7 is a schematic diagram of an equivalent circuit of another embodiment of the intelligent power module of the present application;

[0033] Figure 8 It is a structural schematic diagram of an embodiment of the electronic device of the present application. DETAILED DESCRIPTION

[0034] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. It will be understood that the specific embodiments described herein are only used to explain the present application, rather than to limit the present application. It should also be noted that, for ease of description, only some but not all structures related to the present application are shown in the drawings. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without making creative work are within the scope of protection of the present application.

[0035] The terms "first", "second", etc. in this application are used to distinguish different objects, rather than to describe a specific order. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but optionally includes steps or units that are not listed, or optionally includes other steps or units inherent to these processes, methods, products or devices.

[0036] In addition, the terms "first" or "second" used in this specification to refer to numbers or ordinals are only used for descriptive purposes and cannot be understood as explicitly or implicitly indicating relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of this specification, the meaning of "plurality" is at least two, such as two, three or more, etc., unless otherwise clearly and specifically defined.

[0037] As a module that integrates power devices and their drive circuit chips, the Intelligent Power Module (IPM) has one of its important functions: overcurrent protection to prevent damage to high-power MOSFET or IGBT devices caused by excessive current.

[0038] In the prior art, a sampling resistor Rs is usually set outside the intelligent power module. The sampling resistor Rs is connected in series with the bottom end (U-, V-, W-) of the three-phase bridge arm. The intelligent power module performs voltage sampling through the sampling resistor Rs to detect the short-circuit state of the high-power MOSFET or IGBT device.

[0039] IGBT (Insulated Gate Bipolar Transistor) is a composite fully controlled voltage-driven power semiconductor device composed of BJT (bipolar junction transistor) and MOS (insulated gate field effect transistor). It has the advantages of both MOSFET's high input impedance and GTR's low on-state voltage drop.

[0040] GTR has low saturation voltage drop, high current density, but high driving current; MOSFET has low driving power, fast switching speed, but high conduction voltage drop and low current density. IGBT combines the advantages of the above two devices, with low driving power and low saturation voltage drop, and is very suitable for use in converter systems with DC voltage of 600V and above, such as AC motors, inverters, switching power supplies, lighting circuits, traction drives and other fields.

[0041] Among them, the key to the overcurrent protection circuit is how to realize the current sampling of the power tube. Taking IGBT as an example, sampling through the saturation voltage drop between the collector C and the emitter E is also one of the commonly used methods.

[0042] In current technology, a VCE detection and signal processing circuit is integrated in the HVIC. At the same time, components such as sampling resistors, filter capacitors, and diodes are arranged on the periphery of the HVIC. The VCE detection and signal processing circuit samples and processes the saturation voltage drop between the collector C and the emitter E of the IGBT through peripheral components.

[0043] Since both HVIC and IPM are highly integrated devices, multiple components are arranged around the HVIC, which increases the difficulty of peripheral line wiring and packaging costs.

[0044] Different from the prior art, the present application provides an intelligent power module to simultaneously implement lossless overcurrent detection on the upper bridge IGBT and the lower bridge IGBT, thereby improving detection reliability.

[0045] See also Figure 1 , Figure 1 Schematic diagram of an equivalent circuit of an embodiment of the intelligent power module of the present application. Figure 1 As shown, the intelligent power module 1 includes a high-voltage integrated circuit chip 10, at least one upper bridge IGBT 20 and at least one lower bridge IGBT 30, and the bonding wire of the lower bridge IGBT 30 has a parasitic resistance R B The high-voltage integrated circuit chip 10 includes an over-current protection unit 11 .

[0046] The overcurrent protection unit 11 obtains the saturation voltage between the collector and the emitter of the upper bridge IGBT 20 and obtains the parasitic resistance R of the lower bridge IGBT 30. B The operating current is used to monitor the operating status of the upper bridge IGBT20 and the lower bridge IGBT30.

[0047] Optionally, the high-voltage integrated circuit chip 10 may include a signal processing circuit, which is respectively connected to the overcurrent protection unit 11 , the gate of at least one upper bridge IGBT 20 , and the gate of at least one lower bridge IGBT 30 .

[0048] Among them, the signal processing circuit may include a filtering circuit and a drive control circuit. The signal processing circuit performs signal processing on the acquired saturation voltage and working current through the filtering circuit and the drive control circuit to generate a drive control signal to control the working state of the upper bridge IGBT20 and the lower bridge IGBT30.

[0049] A freewheeling diode can be connected in parallel to the collector of the upper bridge IGBT20 and the emitter of the upper bridge IGBT20, as well as the collector of the lower bridge IGBT30 and the emitter of the lower bridge IGBT30, respectively, to provide a current freewheeling path for the upper bridge IGBT20 and the lower bridge IGBT30, thereby preventing overvoltage from damaging the device when the current of the upper bridge IGBT20 or the lower bridge IGBT30 is reversed.

[0050] like Figure 1 As shown, the overcurrent protection unit 11 includes a first overcurrent protection circuit 111 and a second overcurrent protection circuit 112. The first overcurrent protection circuit 111 obtains the saturation voltage between the collector and the emitter of the upper bridge IGBT 20, and controls the working state of the upper bridge IGBT based on the saturation voltage and the reference voltage. The second overcurrent protection circuit 112 obtains the second detection voltage based on the working current of the lower bridge IGBT 30 to monitor the working state of the lower bridge IGBT 30.

[0051] Combination Figure 1 , see further Figure 2 , Figure 2 1 is a circuit diagram of an embodiment of the first overcurrent protection circuit of the present application. Figure 2 As shown, the first overcurrent protection circuit 111 includes a comparator 1111, a first detection circuit 1112, a second detection circuit 1113 and a voltage source V ref .

[0052] The first input terminal V1 of the comparator 1111 is connected to the collector of the upper bridge IGBT 20 through the first detection circuit 1112. The first detection circuit 1112 obtains a detection voltage based on a saturation voltage between the collector and the emitter of the upper bridge IGBT 20.

[0053] The second input terminal V2 of the comparator 1111 is connected to the voltage source V ref One end of the voltage source V ref The other end of the comparator 1111 is connected to the ground voltage, and the second input terminal V2 of the comparator 1111 is connected to the ground voltage through the voltage source V ref Get the reference voltage V ref Among them, the emitter of the upper bridge IGBT20 is connected to the voltage source V ref The other end is further connected to the ground voltage.

[0054] Where, the voltage source V ref is a constant voltage source, used to provide a reference voltage V to the second input terminal V2 of the comparator 1111ref Furthermore, the voltage source V ref It can be a built-in voltage source of the high-voltage integrated circuit chip 10, without the need to set up an external voltage source, thereby reducing electronic components and improving integration.

[0055] One end of the second detection circuit 1113 is connected to the first input end V1 of the comparator 1111 , and the other end of the second detection circuit 1113 is connected to the ground voltage. The second detection circuit 1113 is used to control the voltage of the first input end V1 of the comparator 1111 .

[0056] Optionally, in this embodiment, the first input terminal V1 of the comparator 1111 is a positive input terminal, and the second input terminal V2 of the comparator 1111 is a negative input terminal. Optionally, in other embodiments, the first input terminal V1 of the comparator 1111 may be a negative input terminal, and the second input terminal V2 of the comparator 1111 may be a positive input terminal.

[0057] Combination Figure 1-2 , see further Figure 3 , Figure 3 1 is a circuit diagram of an embodiment of the first overcurrent protection circuit of the present application. Figure 3 As shown, the first detection circuit 1112 includes a first MOS transistor D1 and a first resistor R1.

[0058] A first end of the first MOS transistor D1 is connected to the collector of the upper bridge IGBT20 , and a gate of the first MOS transistor D1 is connected to the second end of the first MOS transistor D1 .

[0059] One end of the first resistor R1 is connected to the second end of the first MOS transistor D1, and the other end of the first resistor R1 is connected to the first input end V1 of the comparator 1111. The first resistor R1 is a current limiting resistor, which is used to reduce the load end current and limit the current of the first detection circuit 1112 to prevent the comparator 1111 connected in series from being burned out by excessive current.

[0060] Optionally, in this embodiment, the first MOS tube D1 is a high-voltage NMOSFET, the first end of the first MOS tube D1 is the drain of the first MOS tube D1, and the second end of the first MOS tube D1 is the source of the first MOS tube D1. In this embodiment, by using a high-voltage MOSFET as the first MOS tube D1, the upper bridge IGBT 20 is effectively prevented from overcurrent, so that the saturation voltage between the collector and the emitter of the upper bridge IGBT 20 is too large, resulting in an error in the first overcurrent protection circuit 111.

[0061] Optionally, in other embodiments, the first MOS transistor D1 may be a high-voltage PMOSFET, or other transistors or diodes with a high conduction voltage drop.

[0062] like Figure 3As shown, the first overcurrent protection circuit 111 further includes a current source 1114, which is connected to the first input terminal V1 of the comparator 1111 and is used to control the first MOS transistor D1 to be turned on. In this embodiment, the built-in current source of the high-voltage integrated circuit chip 10 is used to provide current to control the first MOS transistor D1 to be turned on, and there is no need to set an external current source, thereby reducing electronic components and improving integration.

[0063] Among them, the current source 1114 is a built-in current source of the high-voltage integrated circuit chip 10, and the current source 1114 outputs current to the first detection circuit 1112. The current is transmitted to the gate of the first MOS tube D1 through the first resistor R1, controlling the first MOS tube D1 to turn on, so that the first detection circuit 1112 is turned on.

[0064] Specifically, the first input terminal V1 of the comparator 1111 obtains a detection voltage through the first detection circuit 1112. The specific calculation formula of the detection voltage is as follows:

[0065] V1=V CESAT +V f +I1*R1

[0066] Among them, V1 is the detection voltage, V CESAT is the saturation voltage between the collector and emitter of the upper bridge IGBT20, V f is the on-state voltage drop of the first MOS tube D1, I1 is the current output by the current source 1114, R1 is the first resistor R1, the product of I1 and R1 is the first voltage, specifically, the voltage generated by the first resistor R1 according to the current flowing through the first resistor R1 generated by the current source 1114, then the detection voltage is the sum of the saturation voltage between the collector and the emitter of the upper bridge IGBT20, the on-state voltage drop of the first MOS tube D1 and the first voltage.

[0067] The second input terminal V2 of the comparator 1111 is connected to the voltage source V ref Get the reference voltage V ref After that, the comparator 1111 will convert the reference voltage V ref The voltage V1 is compared with the detection voltage V1 obtained from the first input terminal V1 of the comparator 1111 .

[0068] Since the saturation voltage between the collector and emitter of the upper bridge IGBT20 is positively correlated with the current flowing through the upper bridge IGBT20, as the current of the upper bridge IGBT20 increases, the saturation voltage between the collector and emitter of the upper bridge IGBT20 increases, and the detection voltage obtained by the first input terminal V1 of the comparator 1111 increases.

[0069] When the detection voltage is greater than the reference voltage V ref When the comparator 1111 generates an output signal V OUT , and the output signal VOUT Output to the subsequent signal processing circuit, the signal processing circuit according to the output signal V OUT A driving control signal is generated and output to the gate of the upper bridge IGBT 20 to control the upper bridge IGBT 20 to stop working, thereby controlling the high-voltage integrated circuit chip 10 to stop working.

[0070] At the same time, the high voltage integrated circuit chip 10 outputs the signal V OUT Output an alarm signal to indicate that the upper bridge IGBT 20 is in an overcurrent state. Wherein, an overcurrent state may occur in the upper bridge IGBT 20 if the operating current of the upper bridge IGBT 20 is too large or the upper bridge IGBT 20 is short-circuited.

[0071] When the high-voltage integrated circuit chip 10 of this embodiment indicates that the upper bridge IGBT 20 is in an overcurrent state, the upper bridge IGBT 20 can be further detected to determine the cause of the overcurrent in the upper bridge IGBT 20 to prevent the short-circuited upper bridge IGBT 20 from being continued to be used, thereby preventing further damage to the high-voltage integrated circuit chip 10 and the intelligent power module 1.

[0072] like Figure 3 As shown, the second detection circuit 1113 includes a second MOS transistor D2, a first end of the second MOS transistor D2 is connected to the first input terminal V1 of the comparator 1111, a second end of the second MOS transistor D2 is connected to the emitter of the upper bridge IGBT20, and the emitter of the upper bridge IGBT20 and the second end of the second MOS transistor D2 are further connected to the ground voltage.

[0073] Optionally, in this embodiment, the second MOS transistor D2 is an NMOSFET, the first end of the second MOS transistor D2 is the source of the second MOS transistor D2, and the second end of the second MOS transistor D2 is the drain of the second MOS transistor D2.

[0074] When the second MOS transistor D2 is turned on, the voltage at the first input terminal V1 of the comparator 1111 is pulled down to the ground voltage; when the second MOS transistor D2 is turned off, the voltage at the first input terminal V1 of the comparator 1111 is the detection voltage.

[0075] The gate of the upper bridge IGBT20 receives the first control signal V in The gate of the second MOS transistor D2 receives the second control signal VT, and the second control signal VT and the first control signal V in Phase-opposite setting.

[0076] Optionally, the gate of the second MOS tube D2 and the gate of the upper bridge IGBT20 are connected to the drive control circuit, and an inverter is provided between the drive control circuit and the gate of the second MOS tube D2, or between the drive control circuit and the gate of the upper bridge IGBT20, so that when the same control signal is transmitted to the second MOS tube D2 and the IGBT device 2, the phases thereof are opposite.

[0077] The inverter may be a TTL NAND gate inverter, a PMOS inverter, an NMOS inverter, a static CMOS inverter, a saturated load digital inverter, a triode inverter or a switch inverter.

[0078] Specifically, when the first control signal Vin is at a low level and the second control signal VT is at a high level, the upper bridge IGBT20 is turned off, the second MOS tube D2 is turned on, the voltage at the first input terminal V1 of the comparator 1111 is the ground voltage, and the first overcurrent protection circuit 111 stops working;

[0079] When the first control signal V in is high level, the second control signal VT is low level, the upper bridge IGBT20 is turned on, the second MOS tube D2 is turned off, the voltage at the first input terminal V1 of the comparator 1111 is the detection voltage, and the first overcurrent protection circuit 111 starts to work.

[0080] The second MOS transistor D2 is a low-voltage MOSFET, and has a smaller on-state voltage drop and a faster response speed, thereby improving the response speed of the first overcurrent protection circuit 111 .

[0081] Combination Figure 1-3 , see further Figure 4 , Figure 4 is a logic diagram of the first overcurrent protection circuit of the present application. The logic changes of the first overcurrent protection circuit 111 are as follows: Figure 4 shown.

[0082] (1) When the second control signal VT is at a high level, the second MOS transistor D2 is turned on, and the voltage V1 at the first input terminal V1 of the comparator 1111 is the ground voltage, that is, V1 is at a low level;

[0083] At this time, the first control signal Vin, which is set in opposite phase to the second control signal VT, is at a low level, the upper bridge IGBT 20 is in a cut-off state, and no current flows through the upper bridge IGBT 20 (leakage current is ignored). At this time, the first overcurrent protection circuit 111 does not work and does not detect, and the output signal Vout output by the comparator 1111 is at a low level.

[0084] (2) When the second control signal VT changes from a high level to a low level, the second MOS transistor D2 is turned off, and the first overcurrent protection circuit 111 can work normally. The voltage V1 of the first input terminal V1 of the comparator 1111 begins to increase, and the saturation voltage V between the collector and the emitter of the saturated upper bridge IGBT20 can be monitored. CESAT ;

[0085] At this time, the first control signal Vin, which is set in phase opposite to the second control signal VT, is at a high level, the upper bridge IGBT 20 is turned on, and current flows through the upper bridge IGBT 20 .

[0086] When the current I through the upper bridge IGBT20 is low, its saturation voltage V CESAT The comparator 1111 outputs an output signal V OUT The output signal is at a low level and there is no fault error, that is, the upper bridge IGBT20 is not short-circuited or overcurrent.

[0087] When the current I through the upper bridge IGBT20 increases, its saturation voltage V CESAT When the current I is higher than a certain value, V1 will be higher than the reference potential Vref, V OUT A high-level signal is output, and the high-voltage integrated circuit chip 10 reports an error, indicating that the upper bridge IGBT 20 is overcurrent or short-circuited.

[0088] The signal processing circuit receives the high-level signal and generates a driving control signal to control the upper bridge IGBT20 to stop working, so as to turn off the upper bridge IGBT20 to prevent the continuous large current from causing damage to the device or equipment;

[0089] At this time, the output signal V output by the comparator 1111 OUT From high level to low level.

[0090] In this embodiment, the high-voltage integrated circuit chip 10 sets the phases of the first control signal Vin and the second control signal VT in opposite directions, so that the first overcurrent protection circuit 111 stops working when the upper bridge IGBT20 is in the cut-off state, and starts working when the upper bridge IGBT20 is in the on state, thereby reducing the power loss of the high-voltage integrated circuit chip 10.

[0091] At the same time, the high-voltage integrated circuit chip 10 of this embodiment obtains the detection voltage in real time through the comparator 1111 and compares it with the reference voltage Vref, so as to monitor the working state of the upper bridge IGBT 20 in real time and prevent the upper bridge IGBT 20 from being in an overcurrent state for a long time.

[0092] like Figure 3As shown, the first overcurrent protection circuit 111 also includes a filter capacitor C1, one end of the filter capacitor C1 is connected to the first end of the second MOS transistor D2, and the other end of the filter capacitor C1 is connected to the second end of the second MOS transistor D2. The filter capacitor C1 is used to eliminate the current noise or interference caused by overshoot generated by the switching state of the upper bridge IGBT20.

[0093] Specifically, the filter capacitor C1 is a leading edge blanking capacitor, and the leading edge blanking time of the filter capacitor C1 is related to the reference voltage V ref Related, the calculation formula of the leading edge blanking time of the filter capacitor C1 is as follows:

[0094] T1=C1*(V ref / I1)

[0095] Where, T1 is the leading edge blanking time of filter capacitor C1, C1 is the capacitance value of filter capacitor C1, V ref is the reference voltage.

[0096] Optionally, one end of the filter capacitor C1 is connected to a voltage source V ref The other end is connected to the emitter of the upper bridge IGBT20 and is further grounded. Specifically, the grounding can be achieved through the ground port GND on the high-voltage integrated circuit chip 10.

[0097] In this embodiment, the first overcurrent protection circuit 111 is disposed in the high-voltage integrated circuit chip 10, and the first overcurrent protection circuit 111 directly obtains the saturation voltage between the collector and the emitter of the upper bridge IGBT 20, and obtains the detection voltage based on the saturation voltage. By comparing the saturation voltage with the reference voltage V ref , determine the working state of the upper bridge IGBT20; when it is determined that the upper bridge IGBT20 is in an overcurrent state, the output drive control signal controls the upper bridge IGBT20 to stop working, and then controls the high-voltage integrated circuit chip 10 to stop working.

[0098] This embodiment integrates the first overcurrent protection circuit 111 into the high-voltage integrated circuit chip 10, thereby reducing the difficulty of peripheral circuit wiring of the high-voltage integrated circuit chip 10 while satisfying the overcurrent protection function of the high-voltage integrated circuit chip 10, further improving the integration level, and reducing the size of the intelligent power module 1 and the packaging cost.

[0099] Combination Figure 1 , see further Figure 5 , Figure 5 1 is a schematic diagram of the structure of an embodiment of the lower bridge IGBT bonding wire of the present application. Figure 5As shown, the lower bridge IGBT 30 and its parallel fast recovery diode 31 (FRD, Fast Recovery Diode) are located on the metal 32, and the fast recovery diode 31 serves as a freewheeling diode of the lower bridge IGBT 30. The metal 32 is a conductive material, which can be a metal element, an alloy (copper alloy, aluminum alloy, etc.) or a composite metal.

[0100] Specifically, the collector of the lower bridge IGBT 30 is connected to the metal 32, the cathode of the fast recovery diode 31 is connected to the metal 32, the emitter of the lower bridge IGBT 30 is connected to the ground wire 33 through the first bonding wire 34, the anode of the fast recovery diode 31 is connected to the ground wire 33 through the second bonding wire 35, and the metal 32 and the ground wire 33 are both arranged on the substrate 36. Optionally, the ground wire 33 is Figure 1 COM port as shown.

[0101] The emitter of the lower bridge IGBT 30 and the ground line 33 are connected via a first bonding line 34 to form a bonding line path. The bonding line path generates a parasitic resistance R B By measuring the resistivity, diameter and length of the first bonding wire 34, the parasitic resistance R B resistance value.

[0102] The high voltage integrated circuit chip 10 includes an ITRIP port. The second overcurrent protection circuit 112 detects through the ITRIP port and utilizes the parasitic resistance R of the first bonding wire 34 between the emitter of the lower bridge IGBT 30 and the ground wire 33. B The collector current of the lower bridge IGBT 30 is detected.

[0103] Specifically, the collector current of the lower bridge IGBT 30 flows through the parasitic resistor R B When the parasitic resistance R B A voltage difference VR will be generated at both ends B , the current flowing through the lower bridge IGBT30 increases, and the parasitic resistance R B The voltage difference between the two ends VR B The second overcurrent protection circuit 112 is connected to the emitter of the lower bridge IGBT 30 to detect the collector current flowing through the first bonding wire 34, that is, to obtain the operating current of the parasitic resistance flowing through the first bonding wire 34, and obtain the parasitic resistance R according to the operating current. B The voltage difference between the two ends VR B , at this time the voltage difference VR B That is the second detection voltage.

[0104] When the second over-current protection circuit 112 detects the voltage difference VR BWhen the second detection voltage exceeds the preset threshold, it can be determined that the lower bridge IGBT30 has an overcurrent. The second overcurrent protection circuit 112 generates an output signal and outputs it to the subsequent signal processing circuit. The signal processing circuit generates a drive control signal according to the output signal, and outputs the drive control signal to the gate of the lower bridge IGBT30 to control the lower bridge IGBT30 to stop working, thereby controlling the high-voltage integrated circuit chip 10 and the intelligent power module 1 to stop working.

[0105] Optionally, the signal processing circuit may further include a signal amplifying circuit, a comparing circuit and a filtering circuit, wherein the second overcurrent protection circuit 112 , the signal amplifying circuit, the comparing circuit, the filtering circuit and the gate of the lower bridge IGBT 30 are connected in sequence.

[0106] Due to the parasitic resistance R B The voltage difference between the two ends VR B The second overcurrent protection circuit 112 can detect the parasitic resistance R through the ITRIP port. B The voltage difference between the two ends VR B , and the voltage difference VR B Output to the signal amplification circuit;

[0107] The signal amplifier circuit converts the voltage difference VR B Amplify the voltage difference VR B The signal is further output to a comparison circuit and a filter circuit for comparison and filtering to generate a drive control signal, and the drive control signal is output to the gate of the lower bridge IGBT30 to control the lower bridge IGBT30 to stop working, thereby controlling and protecting the high-voltage integrated circuit chip 10 and the intelligent power module 1.

[0108] In this embodiment, the second overcurrent protection circuit 112 is connected to the lower bridge IGBT 30 through the parasitic resistance R B To detect the change of the collector current of the lower bridge IGBT30, no additional sampling resistor is required; on the other hand, the detection loop of the second overcurrent protection circuit 112 is located inside the intelligent power module 1, which is different from the prior art in which the sampling resistor and the filter components are located on the PCB board outside the IPM module, resulting in an overcurrent detection loop that is too long. The detection loop of the second overcurrent protection circuit 112 in this embodiment is shortened, reducing the parasitic inductance of the detection loop and the detection signal noise caused by other line noise, resulting in the probability of false triggering of the overcurrent protection.

[0109] Combination Figure 1 , see further Figure 6 , Figure 6 1 is a schematic diagram of another embodiment of the lower bridge IGBT bonding wire of the present application. Figure 6As shown, different from the above embodiment, the emitter of the lower bridge IGBT 30 in this embodiment is connected to the anode of the fast recovery diode 31 through the first bonding wire 34, and the anode of the fast recovery diode 31 is further connected to the ground wire through the second bonding wire 35, so that the emitter of the lower bridge IGBT 30 is connected to the ground wire. The detection principle of the second overcurrent protection circuit 112 is as described in the above embodiment, and will not be repeated here.

[0110] Further reading Figure 7 , Figure 7 FIG. 1 is a schematic diagram of an equivalent circuit of another embodiment of the intelligent power module of the present application. Figure 7 As shown, the intelligent power module 1 of this embodiment includes three upper bridge IGBTs 20 and three lower bridge IGBTs 30 , and the high voltage integrated circuit chip 10 includes three first overcurrent protection circuits 111 and one second overcurrent protection circuit 112 .

[0111] Optionally, in this embodiment, the intelligent power module 1 may use a single 6-channel IGBT device, or three half-bridge IGBT devices.

[0112] The three first overcurrent protection circuits 111 are respectively connected to the three upper bridge IGBTs 20 to perform overcurrent detection protection on the three upper bridge IGBTs 20. The second overcurrent protection circuit 112 is connected to the parasitic resistance R of the bonding wires of the three lower bridge IGBTs 30. B , in order to perform over-current detection and protection on the three lower bridge IGBT30s.

[0113] Optionally, in other embodiments, the high-voltage integrated circuit chip 10 may be provided with three second overcurrent protection circuits 112, so that the three second overcurrent protection circuits 112 are respectively connected to the parasitic resistances R of the first bonding wires 34 of the three lower bridge IGBTs 30. B .

[0114] The present application integrates an overcurrent protection unit 11 into a high-voltage integrated circuit chip 10, and the overcurrent protection unit 11 simultaneously performs overcurrent detection protection on the upper bridge IGBT 20 and the lower bridge IGBT 30 through a first overcurrent protection circuit 111 and a second overcurrent protection circuit 112, thereby improving the detection reliability of the intelligent power module 1.

[0115] This application also provides an electronic device, see Figure 8 , Figure 8 Schematic diagram of the structure of an electronic device according to an embodiment of the present application. Figure 8 As shown, the electronic device 80 includes an intelligent power module 81. The intelligent power module 81 is the intelligent power module 1 disclosed in the above embodiment, which will not be described in detail here.

[0116] Specifically, the intelligent power module 81 is widely used in the field of energy management, among which the energy system in household appliances is the most common energy management field. Therefore, the electronic device 80 can be any household appliance.

[0117] The electronic device 80 may be a refrigeration appliance, such as a household refrigerator, a cold drink machine, etc. The electronic device 80 may be an air conditioner, such as an air conditioner, a hot and cold blower, an electric fan, etc. The electronic device 80 may be a cleaning appliance, such as a washing machine, a dryer, a vacuum cleaner, etc. The electronic device 80 may be a kitchen appliance, such as an electric rice cooker, a microwave oven, an electric oven, etc. The electronic device 80 may be an electric heating appliance, such as an electric blanket, electric heating clothes, a space heater, etc. The electronic device 80 may be an audio-visual appliance, such as a projector, a television, a video recorder, etc.

[0118] Taking a household refrigerator as an example, when an overcurrent occurs in the household refrigerator, the intelligent power module 81 outputs an alarm signal and shuts down the household refrigerator in time to prevent damage to the household refrigerator. At the same time, the intelligent power module 81 monitors the working state of the household refrigerator in real time to improve the reliability of the household refrigerator working system.

[0119] The above description is only an implementation method of the present application, and does not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly used in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. An intelligent power module, characterized in that: The intelligent power module includes a high-voltage integrated circuit chip, at least one upper bridge IGBT and at least one lower bridge IGBT, the bonding wire of the lower bridge IGBT has a parasitic resistance, and the high-voltage integrated circuit chip includes an overcurrent protection unit. The overcurrent protection unit obtains the saturation voltage between the collector and the emitter of the upper bridge IGBT, and obtains the voltage generated by the current of the lower bridge IGBT passing through the parasitic resistor, so as to monitor the working status of the upper bridge IGBT and the lower bridge IGBT; Wherein, the overcurrent protection unit comprises a first overcurrent protection circuit, the first overcurrent protection circuit acquires the saturation voltage, and controls the working state of the upper bridge IGBT based on the saturation voltage and a reference voltage; The first overcurrent protection circuit includes a comparator, a first detection circuit, a second detection circuit and a voltage source; The first input terminal of the comparator is connected to the collector of the upper bridge IGBT through the first detection circuit, and the first detection circuit obtains a first detection voltage based on the saturation voltage; The second input terminal of the comparator is connected to one end of the voltage source, the other end of the voltage source is connected to the ground voltage, and the second input terminal of the comparator obtains the reference voltage through the voltage source; The second detection circuit includes a second MOS tube, a first end of the second MOS tube is connected to the first input end of the comparator, a second end of the second MOS tube is connected to the second input end of the comparator, and the second MOS tube is used to control the voltage of the first input end of the comparator; wherein the gate of the upper bridge IGBT receives a first control signal, the gate of the second MOS tube receives a second control signal, and the second control signal and the first control signal are set in opposite phase.

2. The intelligent power module according to claim 1, characterized in that: The first overcurrent protection circuit further includes a current source, and the first detection circuit includes: A first MOS tube, a first end of which is connected to the collector of the upper bridge IGBT, and a control end of the first MOS tube is connected to the second end of the first MOS tube; A first resistor, one end of which is connected to the second end of the first MOS tube, and the other end of which is connected to the first input end of the comparator; the current source is connected to the first input end of the comparator and is used to control the first MOS tube to be turned on.

3. The intelligent power module according to claim 2, characterized in that: The first detection voltage is the sum of the saturation voltage drop, the conduction voltage drop of the first MOS tube and the first voltage, and the first voltage is the voltage generated by the first resistor according to the current flowing through the first resistor generated by the current source.

4. The intelligent power module according to any one of claims 1 to 3, characterized in that: The overcurrent protection unit includes a second overcurrent protection circuit, and the second overcurrent protection circuit obtains a second detection voltage based on the operating current of the parasitic resistance of the bonding wire to monitor the operating state of the lower bridge IGBT.

5. The intelligent power module according to claim 4, characterized in that: The intelligent power module also includes a ground wire, the emitter of the lower bridge IGBT is connected to the ground wire through the bonding wire, and the second overcurrent protection circuit is connected to the emitter of the lower bridge IGBT to obtain the second detection voltage according to the working current flowing through the bonding wire.

6. The intelligent power module according to claim 4, characterized in that: The intelligent power module further includes a fast recovery diode and a ground wire, the bonding wire includes a first bonding wire and a second bonding wire, the emitter of the lower bridge IGBT is connected to the anode of the fast recovery diode through the first bonding wire, and the anode of the fast recovery diode is connected to the ground wire through the second bonding wire, so that the emitter of the lower bridge IGBT is connected to the ground wire; The second overcurrent protection circuit is connected to the emitter of the lower bridge IGBT, and obtains the second detection voltage according to the operating current flowing through the first bonding wire and the second bonding wire.

7. The intelligent power module according to claim 4, characterized in that: The high-voltage integrated circuit chip includes an ITRIP port, and the second overcurrent protection circuit is detected through the ITRIP port.

8. An electronic device, characterized in that: Comprising the intelligent power module as described in any one of claims 1-7.

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