Circuit for suppressing driving crosstalk between power devices

Abstract

The invention relates to the technical field of power device driving, in particular to a circuit for suppressing driving crosstalk between power devices, and the suppressed driving circuit comprises an upper bridge power device UH, a lower bridge power device UL and a driving module; the positive electrode of the negative voltage source VEE and the ground end of the UL are grounded together; the filter capacitor C1 is connected in parallel between the driving end and the ground end of the UL; after the driving module is electrically connected with the capacitor parallel control module, the capacitor parallel control module is electrically connected between the filter capacitor C1 and the ground end of the UL; when the UL is switched off, the capacitor parallel control module is switched on, so that the filter capacitor C1 is connected in parallel; the negative crosstalk suppression module is electrically connected between the output end of the driving module and the driving end of the UL, is switched on in a delayed manner after UH switch-off and switch-on, is switched off in a delayed manner after UL switch-off and switch-on, and is used for suppressing negative crosstalk caused by UH switch-off and switch-on; the problems that a filter capacitor affects the conduction speed of a power device and the crosstalk suppression effect is not ideal are solved.

Description

Technical Field

[0001] The invention relates to the technical field of power device driving, in particular to a circuit for suppressing driving crosstalk between power devices. Background Art

[0002] Power devices generally include IGBT, MOSFET, etc., which are usually mainly composed of two MOS tubes as the core of the drive circuit, which are connected to the power device through two drive resistors to drive the power device to turn on or off (such as Figure 1 As shown in the figure); when two power devices form a power device group to complete a specific function (such as upper and lower bridge IGBTs to achieve power conversion), during this working process, the change of transient voltage or current will cause electromagnetic radiation. When the power device is turned on or off, the drive circuit will generate high-frequency pulse signals. These signals are transmitted to the power device itself and will form electromagnetic waves in the surrounding space. If the distance between the power devices is too close, or there is a poor electrical connection between the drive signal line and the power device pins, or there is parasitic capacitance between the power device pins (taking IGBT as an example, there is a parasitic capacitance C GC , C GE , C CE ), these electromagnetic waves may affect the behavior of adjacent power devices; for example, when a power device is turned off, the voltage between its drive pin and the ground pin (taking IGBT as an example, between the gate and the emitter) is affected by another power device, resulting in positive crosstalk or negative crosstalk (or positive or negative crosstalk spikes), causing the low level to exceed the zero level or even approach the high level, resulting in the power device being unable to accurately respond to the drive signal and completely shut down, manifested as reduced switching speed, inconsistent turn-on time or prolonged turn-off time, thereby affecting the performance and reliability of the entire system.

[0003] At present, the method of suppressing driving crosstalk is usually to connect a filter capacitor in parallel between the driving pin and the ground pin of the power device (taking IGBT as an example, that is, between the gate and the emitter) to attenuate high-frequency harmonic noise and improve signal quality; although this can suppress crosstalk to a certain extent, it cannot ensure that the voltage between the driving pin and the ground pin of the power device is always below zero level; and the filter capacitor will also reduce the conduction speed of the power device when the power device is turned on; so, in general, the suppression effect is not ideal. Summary of the invention

[0004] In view of the above-mentioned defects, the purpose of the present invention is to provide a circuit for suppressing driving crosstalk between power devices, which solves the problem that the filter capacitor affects the conduction speed of the power device and the crosstalk suppression effect is not ideal.

[0005] To achieve this object, the present invention adopts the following technical solutions:

[0006] A circuit for suppressing driving crosstalk between power devices, wherein the suppressed driving circuit includes an upper bridge power device U H , lower bridge power device U L and a driving module; the upper bridge power device U H and the lower bridge power device U L The output end of the driving module is electrically connected to the lower bridge power device U through the intermediate circuit. L The driving end is electrically connected;

[0007] The driving module includes a negative pressure source V EE , the negative pressure source V EE The positive electrode and the lower bridge power device U L The ground terminals are connected to the ground;

[0008] The suppression circuit includes a filter capacitor C1, a capacitor parallel control module and a negative crosstalk suppression module; the filter capacitor C1 is connected in parallel to the lower bridge power device U L The output end of the driving module is electrically connected to the input end of the capacitor parallel control module, and the output end of the capacitor parallel control module is electrically connected to the filter capacitor C1 and the lower bridge power device U L between the ends of the land;

[0009] When the lower bridge power device U L When turned off, the capacitor parallel control module is turned on, and the filter capacitor C1 is connected in parallel to the lower bridge power device U L Between the driving end and the ground end;

[0010] The negative crosstalk suppression module is electrically connected to the output end of the driving module and the lower bridge power device U L Between the driving ends, in the upper bridge power device U H After the shutdown is turned on, the lower bridge power device U L After the shutdown is turned on, the delay shutdown is used to suppress the upper bridge power device U H Negative crosstalk caused by turn-off to turn-on.

[0011] Furthermore, the negative crosstalk suppression module includes a diode D1, a MOS tube Q2, a comparator COM2, an inverter and a delay circuit; the output end of the driving module is electrically connected to the inverter and the delay circuit in sequence, and then electrically connected to the positive input end of the comparator COM2; the negative input end of the comparator COM2 is connected to the reference voltage V REF2 , the power supply terminal of the comparator COM2 is connected to the positive voltage power supply V CC1 , the ground terminal of the comparator COM2 is connected to the negative voltage power supply V EE1The output end of the comparator COM2 is electrically connected to the gate of the MOS tube Q2, the drain of the MOS tube Q2 is grounded, the source of the MOS tube Q2 is electrically connected to the anode of the diode D1, the cathode of the diode D1 is electrically connected to the lower bridge power device U L The driving end is electrically connected;

[0012] When the positive input terminal of the comparator COM2 receives an inverting driving voltage greater than the reference voltage V REF2 When , the MOS tube Q2 is turned on.

[0013] Furthermore, the delay time of the delay circuit is greater than the upper bridge power device U H The drive signal turns high and the lower bridge power device U L The time difference of the driving signal turning high level is less than the upper bridge power device U H The duration of the high level of the driving signal.

[0014] Furthermore, the capacitor parallel control module includes a MOS tube Q1, a comparator COM1 and a signal acquisition circuit; the output end of the driving module is electrically connected to the signal acquisition circuit and then electrically connected to the negative input end of the comparator COM1; the positive input end of the comparator COM1 is connected to the reference voltage V REF1 , the power supply terminal of the comparator COM1 is connected to the positive voltage power supply V CC1 , the ground terminal of the comparator COM1 is connected to the negative voltage power supply V EE1 , the output end of the comparator COM1 is electrically connected to the gate of the MOS tube Q1, the source of the MOS tube Q1 is grounded, and the drain of the MOS tube Q2 is electrically connected to the filter capacitor C1;

[0015] When the negative input terminal of the comparator COM1 receives a driving voltage less than the reference voltage V REF1 When , the MOS tube Q1 is turned on.

[0016] Furthermore, the delay circuit includes a resistor R3, a resistor R4 and a capacitor C2; the inverter is electrically connected to one end of the resistor R3, the other end of the resistor R3, one end of the resistor R4, and one end of the capacitor C2 are all electrically connected to the positive input terminal of the comparator COM2, and the other end of the resistor R4 and the other end of the capacitor C2 are both grounded.

[0017] Furthermore, the inverter includes a MOS tube Q3 and a MOS tube Q4; the gate of the MOS tube Q3 and the gate of the MOS tube Q4 are both electrically connected to the output end of the driving module, and the source of the MOS tube Q3 is connected to the positive voltage power supply V CC1The source of the MOS tube Q4 is grounded, and the drain of the MOS tube Q3 and the drain of the MOS tube Q4 are both electrically connected to the delay circuit.

[0018] Furthermore, the signal acquisition circuit includes a resistor R1 and a resistor R2; the output end of the driving module is electrically connected to one end of the resistor R1, the other end of the resistor R1 and one end of the resistor R2 are both electrically connected to the negative input end of the comparator COM1, and the other end of the resistor R2 is grounded.

[0019] Furthermore, the driving module further includes a MOS transistor Q5 and a MOS transistor Q6; the source of the MOS transistor Q5 is connected to a positive voltage power supply V CC The gate of the MOS tube Q5 and the gate of the MOS tube Q6 are connected to the input signal, the drain of the MOS tube Q5 and the drain of the MOS tube Q6 are connected to serve as the output end, and the source of the MOS tube Q6 and the negative voltage source V EE The negative electrode is electrically connected to the

[0020] Furthermore, the reference voltage V REF2 is greater than a low level value output by the driving module, and is less than a high level value output by the driving module.

[0021] Furthermore, the reference voltage V REF1 is greater than a low level value output by the driving module, and is less than a high level value output by the driving module.

[0022] The technical solution provided by the present invention may have the following beneficial effects: H and the lower bridge power device U L When the power device U is connected electrically, L For example, only when the driver module drives the lower bridge power device U L When turned off, the control capacitor parallel control module is turned on, so that the filter capacitor C1 is connected in parallel with the lower bridge power device U L between the driving end and the ground end, thereby filtering out the power from the upper bridge device U H Positive and negative crosstalk (mainly the upper bridge power device U H The forward crosstalk caused by the switch-off transition is Figure 3 At t2 in the figure, avoid the lower bridge power device U L It is not possible to accurately respond to the drive signal and completely shut down, and it is also possible to timely switch on the lower bridge power device U L Disconnect the filter capacitor C1 when conducting to avoid affecting the lower bridge power device U L The conduction speed.

[0023] At the same time, based on the lower bridge power device U L The ground terminal is connected to the negative pressure source VEE , ensuring that the lower bridge power device U L When turned off, the crosstalk is filtered out by the filter capacitor C1 and is always less than zero level, optimizing the forward crosstalk suppression effect (such as Figure 3 (as shown in the figure at time t1-t3).

[0024] However, the negative crosstalk suppression module needs to be placed in the upper bridge power device U H After the switch-off (i.e. Figure 3 After the middle t2 moment) delay turn-on, the lower bridge power device U L After the switch-off (i.e. Figure 3 After t5, the delay shutdown is used to suppress the upper bridge power device U H The negative crosstalk caused by the switch-off transition is eliminated; and at this time, the filter capacitor C1 is also in a parallel state, which can help filter out the negative crosstalk and optimize the negative crosstalk suppression effect (such as Figure 3 (as shown in the figure at time t3-t5). BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a driving circuit schematic diagram of an existing power device.

[0026] Figure 2 The present invention is a schematic circuit diagram of a circuit for suppressing driving crosstalk between power devices according to one embodiment of the present invention.

[0027] Figure 3 Yes Figure 2 The upper bridge power device U H (V IN_H ), lower bridge power device U L (V IN_L ), lower bridge power device U L The voltage between the driving end and the ground end (V GE_L ), MOS tube Q1 (V g_Q1 ) and MOS tube Q2 (V g_Q2 ) waveform comparison chart.

[0028] Among them: upper bridge power device U H , lower bridge power device U L , driving module 3, negative pressure source V EE , filter capacitor C1, capacitor parallel control module 1, negative crosstalk suppression module 2, diode D1, MOS tube Q2, comparator COM2, inverter 21, delay circuit 22, MOS tube Q1, comparator COM1, signal acquisition circuit 11, resistor R3, resistor R4, capacitor C2, MOS tube Q3, MOS tube Q4, resistor R1, resistor R2, MOS tube Q5, MOS tube Q6. DETAILED DESCRIPTION

[0029] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0030] In the description of the embodiments of the present invention, the terms "first" and "second" are used for descriptive purposes only and are not to be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the embodiments of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0031] In the description of the embodiments of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected or indirectly connected through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present invention can be understood according to specific circumstances.

[0032] Combine the following Figures 2 to 3 , describing a circuit for suppressing driving crosstalk between power devices according to an embodiment of the present invention.

[0033] A circuit for suppressing driving crosstalk between power devices, wherein the suppressed driving circuit includes an upper bridge power device U H , lower bridge power device U L and drive module 3; upper bridge power device U H and the lower bridge power device U L The output end of the driving module 3 is electrically connected to the lower bridge power device U through the intermediate circuit. L The driving end is electrically connected;

[0034] The driving module 3 includes a negative pressure source V EE , negative pressure source V EE The positive electrode and the lower bridge power device U L The ground terminals are connected to the ground;

[0035] The suppression circuit includes a filter capacitor C1, a capacitor parallel control module 1 and a negative crosstalk suppression module 2; the filter capacitor C1 is connected in parallel to the lower bridge power device U LThe output end of the driving module 3 is electrically connected to the input end of the capacitor parallel control module 1, and the output end of the capacitor parallel control module 1 is electrically connected to the filter capacitor C1 and the lower bridge power device U L between the ends of the land;

[0036] When the lower bridge power device U L When turned off, the capacitor parallel control module 1 is turned on, and the filter capacitor C1 is connected in parallel to the lower bridge power device U L Between the driving end and the ground end;

[0037] The negative crosstalk suppression module 2 is electrically connected to the output end of the driving module 3 and the lower bridge power device U L Between the driving ends of the upper bridge power device U H After the shutdown is turned on, the delay is turned on. L After the shutdown is turned on, the delay is turned off to suppress the upper bridge power device U H Negative crosstalk caused by turn-off to turn-on.

[0038] The present invention proposes a preferred embodiment of a circuit for suppressing driving crosstalk between power devices, such as Figure 2 and 3 As shown, Figure 3 Middle: V IN_H Represents the upper bridge power device U H The turn-on and turn-off conditions, V IN_L Represents the lower bridge power device U L The turn-on and turn-off conditions, V GE_L Represents the lower bridge power device U L The voltage between the driving end and the ground end.

[0039] In the upper bridge power device U H and the lower bridge power device U L When the power device U is connected electrically, L For example, only when the driver module 3 drives the lower bridge power device U L When turned off, the control capacitor parallel control module 1 is turned on, so that the filter capacitor C1 is connected in parallel to the lower bridge power device U L between the driving end and the ground end, thereby filtering out the power from the upper bridge device U H Positive and negative crosstalk (mainly the upper bridge power device U H The forward crosstalk caused by the switch-off transition is Figure 3 At t2 in the figure, avoid the lower bridge power device U L It is not possible to accurately respond to the drive signal and completely shut down, and it is also possible to timely switch on the lower bridge power device U L Disconnect the filter capacitor C1 when conducting to avoid affecting the lower bridge power device U L The conduction speed.

[0040] At the same time, based on the lower bridge power device U L The ground terminal is connected to the negative pressure source V EE , ensuring that the lower bridge power device U L When turned off, the crosstalk is filtered out by the filter capacitor C1 and is always less than zero level, optimizing the forward crosstalk suppression effect (such as Figure 3 (as shown in the figure at time t1-t3).

[0041] However, the negative crosstalk suppression module 2 needs to be connected to the upper bridge power device U H After the switch-off (i.e. Figure 3 After the middle t2 moment) delay turn-on, the lower bridge power device U L After the switch-off (i.e. Figure 3 After t5, the delay shutdown is used to suppress the upper bridge power device U H The negative crosstalk caused by the switch-off transition is eliminated; and at this time, the filter capacitor C1 is also in a parallel state, which can help filter out the negative crosstalk and optimize the negative crosstalk suppression effect (such as Figure 3 (as shown in the figure at time t3-t5).

[0042] It should be noted that the negative crosstalk suppression module 2 is in the upper bridge power device U H The reason why the negative crosstalk suppression module 2 is not turned on before the switch-off is to prevent the filter capacitor C1 from filtering out the positive crosstalk and thus avoid affecting the filtering out of the positive crosstalk. H After the shutdown is turned on, the delay is turned on. L The purpose of delaying shutdown after shutdown and turning on is to turn on in time after the positive crosstalk is filtered out, participate in the suppression of negative crosstalk, and shut down in time after suppression.

[0043] Furthermore, the negative crosstalk suppression module 2 includes a diode D1, a MOS tube Q2, a comparator COM2, an inverter 21 and a delay circuit 22; the output end of the driving module 3 is electrically connected to the inverter 21 and the delay circuit 22 in sequence, and then electrically connected to the positive input end of the comparator COM2; the negative input end of the comparator COM2 is connected to the reference voltage V REF2 , the power supply terminal of comparator COM2 is connected to the positive voltage power supply V CC1 , the ground terminal of comparator COM2 is connected to the negative voltage power supply V EE1 The output end of the comparator COM2 is electrically connected to the gate of the MOS tube Q2, the drain of the MOS tube Q2 is grounded, the source of the MOS tube Q2 is electrically connected to the anode of the diode D1, and the cathode of the diode D1 is electrically connected to the lower bridge power device U L The driving end is electrically connected;

[0044] When the positive input terminal of comparator COM2 receives an inverting driving voltage greater than the reference voltage VREF2 When , MOS tube Q2 is turned on.

[0045] In this embodiment, Figure 2 and 3 As shown, Figure 3 V g_Q2 Represents the on or off status of MOS tube Q2. The negative crosstalk suppression module 2 mainly suppresses the negative crosstalk by the on-voltage of MOS tube Q2 and diode D1 after MOS tube Q2 is turned on. To this end, it is necessary to realize the upper bridge power device U H After the shutdown is turned on, the delay is turned on. L After the shutdown is turned on and then turned off, the reverse driving voltage of the driving module 3 needs to be obtained through the inverter 21, and the reverse driving voltage is sent to the comparator COM2 through the reference voltage V REF2 The MOS tube Q2 is judged to be turned on or off, thereby the lower bridge power device U L The transition point prediction of the upper bridge power device U H The switching point is then delayed by the delay circuit 22 to avoid the lower bridge power device U L The transition point from off to on includes the upper bridge power device U H The switching point from off to on enables the negative crosstalk suppression module 2 to be turned on during the negative crosstalk time period.

[0046] Furthermore, the delay time of the delay circuit 22 is greater than the delay time of the upper bridge power device U H The driving signal turns high and the lower bridge power device U L The time difference of the driving signal turning high level is less than the time difference of the upper bridge power device U H The duration of the high level of the driving signal.

[0047] In this embodiment, in order to prevent the delay circuit 22 from delaying too much and causing the negative crosstalk suppression module 2 to miss the negative crosstalk time period, the delay circuit 22 is set to a delay time greater than the upper bridge power device U H The driving signal turns high and the lower bridge power device U L The time difference of the driving signal turning high level (i.e. Figure 3 The duration from t1 to t2 in the figure is smaller than the duration from t1 to t2 in the figure and ...2 to t2 in the figure and is smaller than the duration from t1 to t2 in the figure and is smaller than the duration from t1 to t H The duration of the high level in the driving signal (i.e. Figure 3 The negative crosstalk suppression module 2 will definitely encounter the upper bridge power device U during the conduction time. H Turn-off to turn-on time (i.e. Figure 3 (at time t4).

[0048] Furthermore, the capacitor parallel control module 1 includes a MOS tube Q1, a comparator COM1 and a signal acquisition circuit 11; the output end of the driving module 3 is electrically connected to the signal acquisition circuit 11, and then electrically connected to the negative input end of the comparator COM1; the positive input end of the comparator COM1 is connected to the reference voltage V REF1 , the power supply terminal of comparator COM1 is connected to the positive voltage power supply V CC1 , the ground terminal of comparator COM1 is connected to the negative voltage power supply V EE1 , the output end of the comparator COM1 is electrically connected to the gate of the MOS tube Q1, the source of the MOS tube Q1 is grounded, and the drain of the MOS tube Q2 is electrically connected to the filter capacitor C1;

[0049] When the negative input terminal of comparator COM1 receives a driving voltage less than the reference voltage V REF1 , MOS tube Q1 is turned on.

[0050] In this embodiment, Figure 2 and 3 As shown, Figure 3 V g_Q1 Represents the on or off status of the MOS tube Q1. The capacitor parallel control module 1 collects the lower bridge power device U through the signal acquisition circuit 11. L The driving voltage is sent to the comparator COM1, which can be REF1 Determine the lower bridge power device U L The on and off conditions of the MOS tube Q1 are controlled so that the MOS tube Q1 is only L When turned off, the filter capacitor C1 is connected in parallel to the lower bridge power device U L The positive and negative crosstalk is suppressed between the driving end and the ground end, and the lower bridge power device U L Disconnect the filter capacitor C1 when conducting to avoid affecting the lower bridge power device U L The conduction speed.

[0051] Furthermore, the delay circuit 22 includes a resistor R3, a resistor R4 and a capacitor C2; the inverter 21 is electrically connected to one end of the resistor R3, the other end of the resistor R3, one end of the resistor R4, and one end of the capacitor C2 are all electrically connected to the positive input terminal of the comparator COM2, and the other end of the resistor R4 and the other end of the capacitor C2 are both grounded.

[0052] In this embodiment, the delay circuit 22 is preferably composed of a resistor R3, a resistor R4 and a capacitor C2 to form an RC charging and discharging circuit, so that the delay time can be configured by the parameter values ​​of the resistor R3, the resistor R4 and the capacitor C2, thereby matching the upper bridge power device U H The duration of the high level of the driving signal.

[0053] Specifically, the delay circuit 22 is Figure 3The charging starts at time t1, and the charging time is used to avoid the upper bridge power device U H At the moment of switching off and on, charging is completed at time t3, and MOS tube Q2 is turned on; after passing through the upper bridge power device U H After the on-off moment, the lower bridge power device U L When the switch is turned off, discharge starts, and the MOS tube Q2 is completely turned off at time t6, entering the next cycle.

[0054] Furthermore, the inverter 21 includes a MOS transistor Q3 and a MOS transistor Q4; the gate of the MOS transistor Q3 and the gate of the MOS transistor Q4 are both electrically connected to the output end of the driving module 3, and the source of the MOS transistor Q3 is connected to the positive voltage power supply V CC1 The source of the MOS tube Q4 is grounded, and the drain of the MOS tube Q3 and the drain of the MOS tube Q4 are both electrically connected to the delay circuit 22 .

[0055] In this embodiment, the MOS transistor Q3 and the MOS transistor Q4 constitute the inverter 21, which can not only realize the inversion effect, but also play the role of filtering, isolation and amplification, so that the subsequent comparator COM2 can accurately determine the lower bridge power device U L The turn-on and turn-off conditions.

[0056] Furthermore, the signal acquisition circuit 11 includes a resistor R1 and a resistor R2; the output end of the driving module 3 is electrically connected to one end of the resistor R1, the other end of the resistor R1 and one end of the resistor R2 are both electrically connected to the negative input end of the comparator COM1, and the other end of the resistor R2 is grounded.

[0057] In this embodiment, the signal acquisition circuit 11 realizes the signal acquisition function by forming a voltage divider circuit through the resistor R1 and the resistor R2.

[0058] Furthermore, the driving module 3 further includes a MOS transistor Q5 and a MOS transistor Q6; the source of the MOS transistor Q5 is connected to a positive voltage power supply V CC The gate of MOS tube Q5 and the gate of MOS tube Q6 are connected to the input signal, the drain of MOS tube Q5 and the drain of MOS tube Q6 are connected to serve as the output terminal, and the source of MOS tube Q6 and the negative voltage source V EE The negative electrode is electrically connected to the

[0059] In this embodiment, the negative pressure source V of the driving module 3 EE To provide a low-side power device U L Providing a negative voltage source to assist the filter capacitor C1 in suppressing positive crosstalk is mainly achieved by connecting the MOS transistor Q5 and the MOS transistor Q6 in the driving module 3 and setting it between the MOS transistor Q6 and the ground. The MOS transistor Q5 and the MOS transistor Q6 drive the lower bridge power device U L When the ground is turned off, the turn-off voltage is the negative voltage source V EE The voltage VEE .

[0060] Furthermore, the reference voltage V REF2 Greater than the low level value output by the driving module 3 , and less than the high level value output by the driving module 3 .

[0061] In this embodiment, the comparator COM2 determines the lower bridge power device U through the positive input terminal. L The reference voltage V REF2 It must be greater than the low level value output by the driver module 3 (driving the lower bridge power device U L off), and must be less than the high level value output by the driver module 3 (driving the lower bridge power device U L conduction).

[0062] Furthermore, the reference voltage V REF1 Greater than the low level value output by the driving module 3 , and less than the high level value output by the driving module 3 .

[0063] In this embodiment, the comparator COM1 determines the lower bridge power device U through the negative input terminal. L The reference voltage V REF1 It must be greater than the low level value output by the driver module 3 (driving the lower bridge power device U L off), and must be less than the high level value output by the driver module 3 (driving the lower bridge power device U L conduction).

[0064] Other structures and operations of a circuit for suppressing driving crosstalk between power devices according to an embodiment of the present invention are known to those skilled in the art and will not be described in detail here.

[0065] In the description of this specification, the description with reference to the terms "embodiment", "example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0066] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A circuit for suppressing driving crosstalk between power devices, characterized in that: The inhibited driving circuit includes the upper bridge power device U H , lower bridge power device U L and a driving module; the upper bridge power device U H and the lower bridge power device U L The output end of the driving module is electrically connected to the lower bridge power device U through the intermediate circuit. L The driving end is electrically connected; The driving module includes a negative pressure source V EE , the negative pressure source V EE The positive electrode and the lower bridge power device U L The ground terminals are connected to the ground; The suppression circuit includes a filter capacitor C1, a capacitor parallel control module and a negative crosstalk suppression module; the filter capacitor C1 is connected in parallel to the lower bridge power device U L The output end of the driving module is electrically connected to the input end of the capacitor parallel control module, and the output end of the capacitor parallel control module is electrically connected to the filter capacitor C1 and the lower bridge power device U L between the ends of the land; When the lower bridge power device U L When turned off, the capacitor parallel control module is turned on, and the filter capacitor C1 is connected in parallel to the lower bridge power device U L Between the driving end and the ground end; The negative crosstalk suppression module is electrically connected to the output end of the driving module and the lower bridge power device U L Between the driving ends, in the upper bridge power device U H After the shutdown is turned on, the lower bridge power device U L After the shutdown is turned on, the delay shutdown is used to suppress the upper bridge power device U H Negative crosstalk caused by turn-off to turn-on.

2. The circuit for suppressing driving crosstalk between power devices according to claim 1, characterized in that: The negative crosstalk suppression module includes a diode D1, a MOS tube Q2, a comparator COM2, an inverter and a delay circuit; the output end of the driving module is electrically connected to the inverter and the delay circuit in sequence, and then electrically connected to the positive input end of the comparator COM2; the negative input end of the comparator COM2 is connected to a reference voltage V REF2 , the power supply terminal of the comparator COM2 is connected to the positive voltage power supply V CC1 , the ground terminal of the comparator COM2 is connected to the negative voltage power supply V EE1 The output end of the comparator COM2 is electrically connected to the gate of the MOS tube Q2, the drain of the MOS tube Q2 is grounded, the source of the MOS tube Q2 is electrically connected to the anode of the diode D1, the cathode of the diode D1 is electrically connected to the lower bridge power device U L The driving end is electrically connected; When the positive input terminal of the comparator COM2 receives an inverting driving voltage greater than the reference voltage V REF2 When , the MOS tube Q2 is turned on.

3. The circuit for suppressing driving crosstalk between power devices according to claim 2, characterized in that: The delay time of the delay circuit is greater than that of the upper bridge power device U H The drive signal turns high and the lower bridge power device U L The time difference of the driving signal turning high level is less than the upper bridge power device U H The duration of the high level of the driving signal.

4. The circuit for suppressing driving crosstalk between power devices according to claim 1, characterized in that: The capacitor parallel control module includes a MOS tube Q1, a comparator COM1 and a signal acquisition circuit; the output end of the driving module is electrically connected to the signal acquisition circuit and then electrically connected to the negative input end of the comparator COM1; the positive input end of the comparator COM1 is connected to a reference voltage V REF1 , the power supply terminal of the comparator COM1 is connected to the positive voltage power supply V CC1 , the ground terminal of the comparator COM1 is connected to the negative voltage power supply V EE1 , the output end of the comparator COM1 is electrically connected to the gate of the MOS tube Q1, the source of the MOS tube Q1 is grounded, and the drain of the MOS tube Q2 is electrically connected to the filter capacitor C1; When the negative input terminal of the comparator COM1 receives a driving voltage less than the reference voltage V REF1 When , the MOS tube Q1 is turned on.

5. The circuit for suppressing driving crosstalk between power devices according to claim 2, characterized in that: The delay circuit includes a resistor R3, a resistor R4 and a capacitor C2; the inverter is electrically connected to one end of the resistor R3, the other end of the resistor R3, one end of the resistor R4, and one end of the capacitor C2 are all electrically connected to the positive input end of the comparator COM2, and the other end of the resistor R4 and the other end of the capacitor C2 are both grounded.

6. The circuit for suppressing driving crosstalk between power devices according to claim 2, characterized in that: The inverter includes a MOS tube Q3 and a MOS tube Q4; the gate of the MOS tube Q3 and the gate of the MOS tube Q4 are both electrically connected to the output end of the driving module, and the source of the MOS tube Q3 is connected to the positive voltage power supply V CC1 The source of the MOS tube Q4 is grounded, and the drain of the MOS tube Q3 and the drain of the MOS tube Q4 are both electrically connected to the delay circuit.

7. The circuit for suppressing driving crosstalk between power devices according to claim 4, characterized in that: The signal acquisition circuit includes a resistor R1 and a resistor R2; the output end of the driving module is electrically connected to one end of the resistor R1, the other end of the resistor R1 and one end of the resistor R2 are both electrically connected to the negative input end of the comparator COM1, and the other end of the resistor R2 is grounded.

8. The circuit for suppressing driving crosstalk between power devices according to claim 1, characterized in that: The driving module also includes a MOS transistor Q5 and a MOS transistor Q6; the source of the MOS transistor Q5 is connected to a positive voltage power supply V CC The gate of the MOS tube Q5 and the gate of the MOS tube Q6 are connected to the input signal, the drain of the MOS tube Q5 and the drain of the MOS tube Q6 are connected to serve as the output end, and the source of the MOS tube Q6 and the negative voltage source V EE The negative electrode is electrically connected to the 9. The circuit for suppressing driving crosstalk between power devices according to claim 2, characterized in that: The reference voltage V REF2 is greater than a low level value output by the driving module, and is less than a high level value output by the driving module.

10. The circuit for suppressing driving crosstalk between power devices according to claim 4, characterized in that: The reference voltage V REF1 is greater than a low level value output by the driving module, and is less than a high level value output by the driving module.

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