CN218416230U - Motor drive circuit and motor driver - Google Patents

Abstract

The application is suitable for the field of motors, and provides a motor driving circuit and a motor driver. A first input end of the first half bridge driving module is electrically connected with the first overshoot suppression module, and a second input end of the first half bridge driving module is electrically connected with the second overshoot suppression module; the first input end of the second half-bridge driving module is electrically connected with the third overshoot suppression module, and the second input end of the second half-bridge driving module is electrically connected with the fourth overshoot suppression module. The motor drive circuit provided by the embodiment of the application is additionally provided with the first overshoot suppression module, the second overshoot suppression module, the third overshoot suppression module and the fourth overshoot suppression module, and can be used for eliminating overshoot voltage generated in the starting or closing process of the motor drive circuit and improving the reliability of the motor driver.

Description

Motor drive circuit and motor driver

Technical Field

The application belongs to the field of motors, and particularly relates to a motor driving circuit and a motor driver.

Background

At present, a driving motor is widely applied to a plurality of fields such as medical equipment, robots and intelligent door locks, and the voltage endurance capability of a motor driving circuit directly influences the reliability of a motor driver. However, an overshoot voltage may be generated during the turn-on or turn-off of the motor driving circuit, which may cause the breakdown of the switching device in the motor driving circuit, resulting in a problem of low reliability of the motor driver.

SUMMERY OF THE UTILITY MODEL

The embodiment of the application provides a motor drive circuit and a motor driver, and can solve the problem that the motor driver has low reliability due to the fact that overshoot voltage is generated in the process of starting or closing the motor drive circuit.

In a first aspect, an embodiment of the present application provides a motor driving circuit, which includes a first half-bridge driving module, a second half-bridge driving module, a first overshoot suppression module, a second overshoot suppression module, a third overshoot suppression module, and a fourth overshoot suppression module, where a first input end of the first half-bridge driving module is electrically connected to the first overshoot suppression module, and a second input end of the first half-bridge driving module is electrically connected to the second overshoot suppression module; the first input end of the second half-bridge driving module is electrically connected with the third overshoot suppression module, and the second input end of the second half-bridge driving module is electrically connected with the fourth overshoot suppression module;

the first overshoot suppression module, the second overshoot suppression module, the third overshoot suppression module, and the fourth overshoot suppression module are all used for eliminating overshoot voltage.

In one possible implementation manner of the first aspect, the first half-bridge driving module includes a first switching unit and a second switching unit;

the first end of the first switch unit is electrically connected with a first power supply, the second end of the first switch unit is electrically connected with the first end of the second switch unit, and the control end of the first switch unit is used as the first input end of the first half-bridge driving module; and the second end of the second switch unit is grounded, and the control end of the second switch unit is used as the second input end of the first half-bridge driving module.

In a possible implementation manner of the first aspect, the first switch unit includes a first switch tube, and the second switch unit includes a second switch tube;

the source electrode of the first switch tube is electrically connected with a first power supply, the drain electrode of the first switch tube is electrically connected with the drain electrode of the second switch tube, the grid electrode of the first switch tube is electrically connected with the first overshoot suppression module, the source electrode of the second switch tube is grounded, and the grid electrode of the second switch tube is electrically connected with the second overshoot suppression module.

In a possible implementation manner of the first aspect, the first overshoot suppression module includes a first resistor and a fifth switching tube;

the first resistor is electrically connected with the drain electrode of the fifth switching tube and the grid electrode of the first switching tube respectively, and the grid electrode of the fifth switching tube is electrically connected with the source electrode of the fifth switching tube and the second power supply respectively.

In a possible implementation manner of the first aspect, the second overshoot suppression module includes a second resistor and a sixth switching tube;

the second resistor is electrically connected with the drain electrode of the sixth switching tube and the grid electrode of the second switching tube respectively, and the grid electrode of the sixth switching tube and the source electrode of the sixth switching tube are electrically connected and grounded.

In one possible implementation of the first aspect, the second half-bridge driving module includes a third switching unit and a fourth switching unit;

a first end of the third switching unit is electrically connected with a third power supply, a second end of the third switching unit is electrically connected with a first end of the fourth switching unit, and a control end of the third switching unit is used as a first input end of the second half-bridge driving module; a second end of the fourth switching unit is grounded, and a control end of the fourth switching unit is used as a second input end of the second half-bridge driving module.

In a possible implementation manner of the first aspect, the third switching unit includes a third switching tube, and the fourth switching unit includes a fourth switching tube;

the source electrode of the third switching tube is electrically connected with a third power supply, the drain electrode of the third switching tube is electrically connected with the drain electrode of the fourth switching tube, the grid electrode of the third switching tube is electrically connected with the third overshoot suppression module, the source electrode of the fourth switching tube is grounded, and the grid electrode of the fourth switching tube is electrically connected with the fourth overshoot suppression module.

In a possible implementation manner of the first aspect, the third overshoot suppression module includes a third resistor and a seventh switching tube;

the third resistor is respectively and electrically connected with the drain electrode of the seventh switching tube and the grid electrode of the third switching tube, and the grid electrode of the seventh switching tube is respectively and electrically connected with the source electrode of the seventh switching tube and the fourth power supply.

In a possible implementation manner of the first aspect, the fourth overshoot suppression module includes a fourth resistor and an eighth switching tube;

the fourth resistor is electrically connected with the drain electrode of the eighth switching tube and the grid electrode of the fourth switching tube respectively, and the grid electrode of the eighth switching tube and the source electrode of the eighth switching tube are electrically connected and grounded.

In a second aspect, embodiments of the present application provide a motor driver, including the motor driving circuit described in any one of the first aspects.

Compared with the prior art, the embodiment of the application has the beneficial effects that:

the motor drive circuit provided by the embodiment of the application comprises a first half-bridge drive module and a second half-bridge drive module, wherein the first half-bridge drive module and the second half-bridge drive module jointly drive a motor. Meanwhile, the motor driving circuit is additionally provided with the first overshoot suppression module, the second overshoot suppression module, the third overshoot suppression module and the fourth overshoot suppression module, when the motor driving circuit is started or closed, if the input end of the first half-bridge driving module or the second half-bridge driving module generates overshoot voltage, the overshoot suppression modules (the first overshoot suppression module, the second overshoot suppression module, the third overshoot suppression module and the fourth overshoot suppression module) can eliminate the overshoot voltage, switching devices in the first half-bridge driving module and the second half-bridge driving module are prevented from being broken down, the motor driving circuit is ensured to work normally, and the reliability of a motor driver is improved.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required to be used in the embodiments or the prior art description will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and for those skilled in the art, other drawings may be obtained according to these drawings without inventive labor.

FIG. 1 is a schematic block diagram of a motor drive circuit provided in an embodiment of the present application;

FIG. 2 is a schematic circuit diagram of a motor driving circuit according to an embodiment of the present application;

FIG. 3 is a schematic diagram illustrating a motor driving circuit controlling a motor to rotate clockwise according to an embodiment of the present application;

fig. 4 is a schematic diagram illustrating that a motor driving circuit controls a motor to rotate counterclockwise according to an embodiment of the present application.

In the figure: 101. a first overshoot suppression module; 102. a second overshoot suppression module; 103. a third overshoot suppression module; 104. a fourth overshoot suppression module; 201. a first switch unit; 202. a second switching unit; 203. a third switching unit; 204. a fourth switching unit; 01. a first half-bridge drive module; 02. a second half-bridge drive module.

Detailed Description

In the following description, for purposes of explanation and not limitation, specific details are set forth, such as particular system structures, techniques, etc. in order to provide a thorough understanding of the embodiments of the present application. It will be apparent, however, to one skilled in the art that the present application may be practiced in other embodiments that depart from these specific details. In other instances, detailed descriptions of well-known systems, devices, circuits, and methods are omitted so as not to obscure the description of the present application with unnecessary detail.

It will be understood that the terms "comprises" and/or "comprising," when used in this specification and the appended claims, specify the presence of stated features, 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.

As used in the specification and appended claims, the term "if" may be interpreted contextually as "when 8230that" or "upon" or "in response to a determination" or "in response to a detection". Similarly, the phrase "if it is determined" or "if a [ described condition or event ] is detected" may be interpreted contextually to mean "upon determining" or "in response to determining" or "upon detecting [ described condition or event ]" or "in response to detecting [ described condition or event ]".

Furthermore, in the description of the present application and the appended claims, the terms "first," "second," "third," and the like are used for distinguishing between descriptions and not necessarily for describing a relative importance or importance.

Reference throughout this specification to "one embodiment" or "some embodiments," or the like, means that a particular feature, structure, or characteristic described in connection with the embodiment is included in one or more embodiments of the present application. Thus, appearances of the phrases "in one embodiment," "in some embodiments," "in other embodiments," or the like, in various places throughout this specification are not necessarily all referring to the same embodiment, but rather mean "one or more but not all embodiments" unless specifically stated otherwise. The terms "comprising," "including," "having," and variations thereof mean "including, but not limited to," unless expressly specified otherwise.

Overshoot voltage is generated during the on or off process of the motor driving circuit, so that the motor driver has the problem of low reliability.

Based on the above problem, the motor driving circuit provided by the embodiment of the application includes a first half-bridge driving module and a second half-bridge driving module, and the first half-bridge driving module and the second half-bridge driving module jointly realize driving of the motor. Meanwhile, the motor driving circuit is additionally provided with the first overshoot suppression module, the second overshoot suppression module, the third overshoot suppression module and the fourth overshoot suppression module, when the motor driving circuit is started or closed, if the input end of the first half-bridge driving module or the second half-bridge driving module generates overshoot voltage, the overshoot suppression modules (the first overshoot suppression module, the second overshoot suppression module, the third overshoot suppression module and the fourth overshoot suppression module) can eliminate the overshoot voltage, switching devices in the first half-bridge driving module and the second half-bridge driving module are prevented from being broken down, the motor driving circuit is ensured to work normally, and the reliability of a motor driver is improved.

In order to explain the technical means described in the present application, the following description will be given by way of specific examples.

Fig. 1 shows a schematic block diagram of a motor driving circuit provided in an embodiment of the present application. Referring to fig. 1, the motor driving circuit includes a first half-bridge driving module 01, a second half-bridge driving module 02, a first overshoot suppression module 101, a second overshoot suppression module 102, a third overshoot suppression module 103, and a fourth overshoot suppression module 104, wherein a first input terminal of the first half-bridge driving module 01 is electrically connected to the first overshoot suppression module 101, and a second input terminal of the first half-bridge driving module 01 is electrically connected to the second overshoot suppression module 102; a first input end of the second half-bridge drive module 02 is electrically connected with the third overshoot suppression module 103, and a second input end of the second half-bridge drive module 02 is electrically connected with the fourth overshoot suppression module 104; the first 101, second 102, third 103 and fourth 104 overshoot suppression modules are used to eliminate the overshoot voltage.

Specifically, when the motor driving circuit is in a use state, the first end of the first half-bridge driving module 01 is electrically connected with the first power VCC1, the first end of the second half-bridge driving module 02 is electrically connected with the third power VCC3, the second end of the first half-bridge driving module 01 and the second end of the second half-bridge driving module 02 are both grounded, and the output end of the first half-bridge driving module 01 and the output end of the second half-bridge driving module 02 are both electrically connected with the motor M. The control unit is electrically connected to the first input terminal of the first half-bridge drive module 01 through the first overshoot suppression module 101, and is configured to input a first voltage signal to the first input terminal of the first half-bridge drive module 01. The control unit is electrically connected to the second input terminal of the first half-bridge driver module 01 through the second overshoot suppression module 102, and is configured to input a second voltage signal to the second input terminal of the first half-bridge driver module 01. The control unit is electrically connected to the first input terminal of the second half-bridge driver module 02 through the third overshoot suppression module 103, and is configured to input a third voltage signal to the first input terminal of the second half-bridge driver module 02. The control unit is electrically connected to the second input terminal of the second half-bridge drive module 02 via the fourth overshoot suppression module 104, and is configured to input a fourth voltage signal to the second input terminal of the second half-bridge drive module 02. The first half-bridge driving module 01 outputs a first driving signal according to the first voltage signal and the second voltage signal, and the second half-bridge driving module 02 outputs a second driving signal according to the third voltage signal and the fourth voltage signal, wherein the first driving signal and the second driving signal can control the rotation of the motor M.

Illustratively, if the current output by the first power source VCC1 sequentially flows through the first half-bridge driving module 01, the motor M, and the second half-bridge driving module 02 to flow back to the ground, at this time, the first half-bridge driving module 01 outputs a high level to the motor M, and the second half-bridge driving module 02 outputs a low level to the motor M, so as to drive the motor M to rotate clockwise. If the current output by the third power VCC3 flows through the second half-bridge driving module 02, the motor M, and the first half-bridge driving module 01 in sequence to flow back to the ground, at this time, the second half-bridge driving module 02 outputs a high level to the motor M, the first half-bridge driving module 01 outputs a low level to the motor M, and the motor M is driven to rotate counterclockwise.

The first voltage signal, the second voltage signal, the third voltage signal and the fourth voltage signal may be PWM signals, and the duty ratio of the PWM signals may be adjusted to adjust the rotation speed of the motor M. For example, if the duty ratio of the PWM signal is 100%, the rotation speed of the motor M is 1000r/min, and if the duty ratio of the PWM signal is 50%, the rotation speed of the motor M is 500r/min.

It should be noted that, the motor M is an inductive load element, a voltage coupling phenomenon exists at the instant of turning on or off the motor driving circuit, the instant of starting the motor M, and the instant of switching the steering mode of the motor M, an overshoot voltage is generated at the input ports of the first half-bridge driving module 01 and the second half-bridge driving module 02, and a peak value of the overshoot voltage is far greater than a voltage value that can be borne by the switching device, so that the switching device is damaged, the motor driving circuit cannot be normally turned on or off, and the normal operation of the motor M is further affected.

The motor driving circuit provided by the embodiment of the application is provided with a first overshoot suppression module 101, a second overshoot suppression module 102, a third overshoot suppression module 103 and a fourth overshoot suppression module 104. The first overshoot suppression module 101 can eliminate the overshoot voltage at the first input terminal of the first half-bridge drive module 01, the second overshoot suppression module 102 can eliminate the overshoot voltage at the second input terminal of the first half-bridge drive module 01, the third overshoot suppression module 103 can eliminate the overshoot voltage at the first input terminal of the second half-bridge drive module 02, and the fourth overshoot suppression module 104 can eliminate the overshoot voltage at the second input terminal of the second half-bridge drive module 02, so as to prevent the overshoot voltage from damaging the switching devices in the first half-bridge drive module 01 and the second half-bridge drive module 02, ensure the normal operation of the motor drive circuit, and improve the reliability of the motor driver.

In one embodiment of the present application, the first half-bridge driving module 01 includes a first switching unit 201 and a second switching unit 202; a first end of the first switch unit 201 is electrically connected to a first power VCC1, a second end of the first switch unit 201 is electrically connected to a first end of the second switch unit 202, and a control end of the first switch unit 201 serves as a first input end of the first half-bridge drive module 01; a second terminal of the second switch unit 202 is grounded, and a control terminal of the second switch unit 202 serves as a second input terminal of the first half-bridge driving module 01.

The second half-bridge driving module 02 includes a third switching unit 203 and a fourth switching unit 204; a first terminal of the third switching unit 203 is electrically connected to the third power VCC3, a second terminal of the third switching unit 203 is electrically connected to a first terminal of the fourth switching unit 204, and a control terminal of the third switching unit 203 serves as a first input terminal of the second half-bridge driving module 02; a second terminal of the fourth switching unit 204 is grounded, and a control terminal of the fourth switching unit 204 serves as a second input terminal of the second half-bridge driving module 02.

Specifically, the first voltage signal and the fourth voltage signal control the first switch unit 201 and the fourth switch unit 204 to be turned on simultaneously (that is, the voltage values of the first voltage signal and the fourth voltage signal are greater than the turn-on voltages of the first switch unit 201 and the fourth switch unit 204), the second voltage signal and the third voltage signal control the second switch unit 202 and the third switch unit 203 to be turned off simultaneously, so that the current output by the first power source VCC1 sequentially flows through the first switch unit 201, the motor M, and the fourth switch unit 204 to flow back to the ground, at this time, the first switch unit 201 outputs a high level to the motor M, and the fourth switch unit 204 outputs a low level to the motor M, so as to drive the motor M to rotate clockwise.

The second voltage signal and the third voltage signal control the second switch unit 202 and the third switch unit 203 to be turned on simultaneously (i.e. the voltage values of the second voltage signal and the third voltage signal are greater than the turn-on voltages of the second switch unit 202 and the third switch unit 203), the first voltage signal and the fourth voltage signal control the first switch unit 201 and the fourth switch unit 204 to be turned off simultaneously, so that the current output by the third power source VCC3 sequentially flows through the third switch unit 203, the motor M and the second switch unit 202 to return to the ground, at this time, the third switch unit 203 outputs a high level to the motor M, the second switch unit 202 outputs a low level to the motor M, and the motor M is driven to rotate counterclockwise.

It should be noted that the first voltage signal and the second voltage signal cannot control the first switch unit 201 and the second switch unit 202 to be turned on simultaneously, otherwise, the current output by the first power supply VCC1 is too large, and the device is damaged. The third switching unit 203 and the fourth switching unit 204 cannot be controlled to be turned on simultaneously by the third voltage signal and the fourth voltage signal, otherwise, the current output by the third power supply VCC3 is too large, and the device is damaged.

For example, the first power source VCC1 and the third power source VCC3 may be the same power source or two different power sources.

Fig. 2 shows a schematic circuit connection diagram of a motor driving circuit provided in an embodiment of the present application. Referring to fig. 2, the first switching unit 201 includes a first switching tube M1, and the second switching unit 202 includes a second switching tube M2; the source of the first switch tube M1 is electrically connected to the first power source VCC1, the drain of the first switch tube M1 is electrically connected to the drain of the second switch tube M2, the gate of the first switch tube M1 is electrically connected to the first overshoot suppression module 101, the source of the second switch tube M2 is grounded, and the gate of the second switch tube M2 is electrically connected to the second overshoot suppression module 102.

The third switching unit 203 comprises a third switching tube M3, and the fourth switching unit 204 comprises a fourth switching tube M4; the source of the third switching tube M3 is electrically connected to the third power source VCC3, the drain of the third switching tube M3 is electrically connected to the drain of the fourth switching tube M4, the gate of the third switching tube M3 is electrically connected to the third overshoot suppression module 103, the source of the fourth switching tube M4 is grounded, and the gate of the fourth switching tube M4 is electrically connected to the fourth overshoot suppression module 104.

Specifically, as shown in fig. 3, the first voltage signal and the fourth voltage signal control the first switch tube M1 and the fourth switch tube M4 to be turned on simultaneously (that is, the voltage values of the first voltage signal and the fourth voltage signal are greater than the turn-on voltages of the first switch tube M1 and the fourth switch tube M4), the second voltage signal and the third voltage signal control the second switch tube M2 and the third switch tube M3 to be turned off simultaneously, so that the current output by the first power VCC1 sequentially flows through the source and the drain of the first switch tube M1, the drain of the motor M, and the drain and the source of the fourth switch tube M4 to flow back to the ground, at this time, the drain of the first switch tube M1 outputs a high level to the motor M, and the drain of the fourth switch tube M4 outputs a low level to the motor M, so as to drive the motor M to rotate clockwise.

As shown in fig. 4, the second voltage signal and the third voltage signal control the second switching tube M2 and the third switching tube M3 to be turned on simultaneously (i.e. the voltage values of the second voltage signal and the third voltage signal are greater than the turn-on voltages of the second switching tube M2 and the third switching tube M3), the first voltage signal and the fourth voltage signal control the first switching tube M1 and the fourth switching tube M4 to be turned off simultaneously, so that the current output by the third power source VCC3 sequentially flows through the source and the drain of the third switching tube M3, the motor M, and the drain and the source of the second switching tube M2 to flow back to the ground, at this time, the drain of the third switching tube M3 outputs a high level to the motor M, and the drain of the second switching tube M2 outputs a low level to the motor M, so as to drive the motor M to rotate counterclockwise.

It should be noted that, in the process of controlling the first switching tube M1 to be turned on or turned off by the first voltage signal, controlling the second switching tube M2 to be turned on or turned off by the second voltage signal, controlling the third switching tube M3 to be turned on or turned off by the third voltage signal, and controlling the fourth switching tube M4 to be turned on or turned off by the fourth voltage signal, a voltage coupling phenomenon may occur, and overshoot voltages are generated on the gate of the first switching tube M1, the gate of the second switching tube M2, the gate of the third switching tube M3, and the gate of the fourth switching tube M4, and the first overshoot suppression module 101, the second overshoot suppression module 102, the third overshoot suppression module 103, and the fourth overshoot suppression module 104 are all used to eliminate the overshoot voltages, so as to implement overshoot suppression on the motor driving circuit, and ensure conduction of the first switching tube M1, the second switching tube M2, the third switching tube M3, and the fourth switching tube M4, thereby ensuring normal operation of the motor M and improving reliability of the motor driver.

For example, the first switching tube M1 and the third switching tube M3 are both P-type switching tubes, and the second switching tube M2 and the fourth switching tube M4 are both N-type switching tubes.

As shown in fig. 2 to 4, the first overshoot suppression module 101 includes a first resistor R1 and a fifth switch M5; the first resistor R1 is electrically connected to the drain of the fifth switch tube M5 and the gate of the first switch tube M1, respectively, and the gate of the fifth switch tube M5 is electrically connected to the source of the fifth switch tube M5 and the second power source VCC2, respectively.

Specifically, the first resistor R1 may be used as a delay resistor, and may adjust the on-off time of the first switching tube M1. For example, the resistance value of R1 is increased, so that the switching rate of the first switching tube M1 can be slowed down, and the phenomenon that the switching rate is too fast to generate a large voltage pulse to damage the first switching tube M1 is avoided.

The gate of the fifth switching tube M5 is electrically connected to the source of the fifth switching tube M5, at this time, the fifth switching tube M5 is equivalent to a diode, when a large overshoot voltage is generated at the gate of the first switching tube M1 due to voltage coupling and the like, and the voltage of the second power source VCC2 is unstable, the overshoot voltage value may be larger than the voltage value of the second power source VCC2, and a current is drained to the second power source VCC2, which is equivalent to a reverse breakdown of the diode. The overshoot voltage is eliminated, the overshoot suppression of the motor driving circuit is realized, the conduction of the first switch tube M1 is ensured, the normal work of the motor M is further ensured, and the reliability of the motor driver is improved.

It should be noted that, within a certain range, such as within the diode reverse breakdown voltage range, the fifth switching tube M5 may be replaced by a diode, and the function of the fifth switching tube M5 for eliminating the overshoot voltage is similar to electrostatic discharge (ESD).

Illustratively, the fifth switch tube M5 is a P-type switch tube.

As shown in fig. 2 to 4, the second overshoot suppression module 102 includes a second resistor R2 and a sixth switching transistor M6; the second resistor R2 is electrically connected to the drain of the sixth switching tube M6 and the gate of the second switching tube M2, respectively, and the gate of the sixth switching tube M6 and the source of the sixth switching tube M6 are electrically connected and grounded.

Specifically, the second resistor R2 may be used as a delay resistor, and may adjust the on-off time of the second switching tube M2. For example, the resistance value of R2 is increased, so that the switching rate of the second switching tube M2 can be slowed down, and the second switching tube M2 is prevented from being damaged due to a large voltage pulse caused by an excessively fast switching rate.

The gate of the sixth switching tube M6 is electrically connected to the source of the sixth switching tube M6, and the sixth switching tube M6 is equivalent to a diode, when a large overshoot voltage is generated at the gate of the second switching tube M2 due to voltage coupling, and the like, the voltage of the ground is unstable, and the overshoot voltage value may be larger than the voltage value of the ground, and the current will be drained to the ground, which is equivalent to a reverse breakdown of the diode. The overshoot voltage is eliminated, the overshoot suppression of the motor driving circuit is realized, the conduction of the second switch tube M2 is ensured, the normal work of the motor M is further ensured, and the reliability of the motor driver is improved.

It should be noted that, within a certain range, such as within the diode reverse breakdown voltage range, the sixth switching tube M6 may be replaced by a diode, and the function of the sixth switching tube M6 for eliminating the overshoot voltage is similar to electrostatic discharge (ESD).

Illustratively, the sixth switching tube M6 is an N-type switching tube.

As shown in fig. 2 to 4, the third overshoot suppression module 103 includes a third resistor R3 and a seventh switch M7; the third resistor R3 is electrically connected to the drain of the seventh switch M7 and the gate of the third switch M3, respectively, and the gate of the seventh switch M7 is electrically connected to the source of the seventh switch M7 and the fourth power VCC4, respectively.

Specifically, the third resistor R3 may be used as a delay resistor, and the on/off time of the third switching tube M3 may be adjusted. For example, if the resistance of R3 is increased, the switching rate of the third switching tube M3 can be slowed down, so as to prevent the third switching tube M3 from being damaged due to a large voltage pulse caused by an excessively fast switching rate.

The gate of the seventh switching transistor M7 is electrically connected to the source of the seventh switching transistor M7, at this time, the seventh switching transistor M7 is equivalent to a diode, when a large overshoot voltage is generated at the gate of the third switching transistor M3 due to voltage coupling and the like, the voltage of the fourth power source VCC4 is unstable, the overshoot voltage value may be larger than the voltage value of the fourth power source VCC4, and a current is drained to the fourth power source VCC4, which is equivalent to a reverse breakdown of the diode. The overshoot voltage is eliminated, the overshoot suppression of the motor driving circuit is realized, the conduction of the third switching tube M3 is ensured, the normal work of the motor M is further ensured, and the reliability of the motor driver is improved.

It should be noted that, in a certain range, such as in the range of the reverse breakdown voltage of the diode, the seventh switching tube M7 may be replaced by a diode, and the function of the seventh switching tube M7 to eliminate the overshoot voltage is similar to electrostatic discharge (ESD).

Illustratively, the seventh switch tube M7 is a P-type switch tube.

As shown in fig. 2 to 4, the fourth overshoot suppression module 104 includes a fourth resistor R4 and an eighth switch transistor M8; the fourth resistor R4 is electrically connected to the drain of the eighth switching tube M8 and the gate of the fourth switching tube M4, respectively, and the gate of the eighth switching tube M8 and the source of the eighth switching tube M8 are electrically connected and grounded.

Specifically, the fourth resistor R4 may be used as a delay resistor, and may adjust the on-off time of the fourth switching tube M4. For example, the resistance value of R4 is increased, so that the switching rate of the fourth switching tube M4 can be reduced, and the situation that the fourth switching tube M4 is damaged due to large voltage pulse caused by excessively fast switching rate is avoided.

The gate of the eighth switching transistor M8 is electrically connected to the source of the eighth switching transistor M8, and at this time, the eighth switching transistor M8 is equivalent to a diode, and when a large overshoot voltage is generated at the gate of the fourth switching transistor M4 due to voltage coupling or the like, the voltage of the ground is unstable, and the overshoot voltage value at this time may be greater than the voltage value of the ground, and the current will be drained to the ground, which is equivalent to a reverse breakdown of the diode. The overshoot voltage is eliminated, the overshoot suppression of the motor driving circuit is realized, the conduction of the fourth switching tube M4 is ensured, the normal work of the motor M is further ensured, and the reliability of the motor driver is improved.

It should be noted that, within a certain range, such as within the diode reverse breakdown voltage range, the eighth switch transistor M8 may be replaced by a diode, and the function of the eighth switch transistor M8 for eliminating the overshoot voltage is similar to electrostatic discharge (ESD).

Illustratively, the eighth switch tube M8 is an N-type switch tube.

The application also discloses a motor driver, including foretell motor drive circuit, motor driver adopts foretell motor drive circuit, can avoid producing the voltage of overshooting at motor drive circuit opening or closing in-process, improves motor driver's reliability.

The above-mentioned embodiments are only used for illustrating the technical solutions of the present application, and not for limiting the same; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; such modifications and substitutions do not depart from the spirit and scope of the embodiments of the present application, and they should be construed as being included in the present application.

Claims (10)

1. A motor driving circuit is characterized by comprising a first half-bridge driving module, a second half-bridge driving module, a first overshoot suppression module, a second overshoot suppression module, a third overshoot suppression module and a fourth overshoot suppression module, wherein a first input end of the first half-bridge driving module is electrically connected with the first overshoot suppression module, and a second input end of the first half-bridge driving module is electrically connected with the second overshoot suppression module; the first input end of the second half-bridge driving module is electrically connected with the third overshoot suppression module, and the second input end of the second half-bridge driving module is electrically connected with the fourth overshoot suppression module;

the first overshoot suppression module, the second overshoot suppression module, the third overshoot suppression module, and the fourth overshoot suppression module are all used for eliminating overshoot voltage.

2. The motor drive circuit of claim 1, wherein the first half-bridge drive module comprises a first switching unit and a second switching unit;

the first end of the first switch unit is electrically connected with a first power supply, the second end of the first switch unit is electrically connected with the first end of the second switch unit, and the control end of the first switch unit is used as the first input end of the first half-bridge driving module; and the second end of the second switch unit is grounded, and the control end of the second switch unit is used as the second input end of the first half-bridge driving module.

3. The motor drive circuit according to claim 2, wherein the first switching unit comprises a first switching tube, and the second switching unit comprises a second switching tube;

the source electrode of the first switch tube is electrically connected with a first power supply, the drain electrode of the first switch tube is electrically connected with the drain electrode of the second switch tube, the grid electrode of the first switch tube is electrically connected with the first overshoot suppression module, the source electrode of the second switch tube is grounded, and the grid electrode of the second switch tube is electrically connected with the second overshoot suppression module.

4. The motor drive circuit of claim 3, wherein the first overshoot suppression module comprises a first resistor and a fifth switching tube;

the first resistor is respectively and electrically connected with the drain electrode of the fifth switch tube and the grid electrode of the first switch tube, and the grid electrode of the fifth switch tube is respectively and electrically connected with the source electrode of the fifth switch tube and the second power supply.

5. The motor drive circuit of claim 3, wherein the second overshoot suppression module comprises a second resistor and a sixth switching tube;

the second resistor is electrically connected with the drain electrode of the sixth switching tube and the grid electrode of the second switching tube respectively, and the grid electrode of the sixth switching tube and the source electrode of the sixth switching tube are electrically connected and grounded.

6. The motor drive circuit of claim 1 wherein the second half-bridge drive module comprises a third switching unit and a fourth switching unit;

a first end of the third switching unit is electrically connected with a third power supply, a second end of the third switching unit is electrically connected with a first end of the fourth switching unit, and a control end of the third switching unit is used as a first input end of the second half-bridge driving module; a second end of the fourth switching unit is grounded, and a control end of the fourth switching unit is used as a second input end of the second half-bridge driving module.

7. The motor drive circuit according to claim 6, wherein the third switching unit includes a third switching tube, and the fourth switching unit includes a fourth switching tube;

the source electrode of the third switching tube is electrically connected with a third power supply, the drain electrode of the third switching tube is electrically connected with the drain electrode of the fourth switching tube, the grid electrode of the third switching tube is electrically connected with the third overshoot suppression module, the source electrode of the fourth switching tube is grounded, and the grid electrode of the fourth switching tube is electrically connected with the fourth overshoot suppression module.

8. The motor drive circuit of claim 7, wherein the third overshoot suppression module comprises a third resistor and a seventh switching tube;

the third resistor is respectively and electrically connected with the drain electrode of the seventh switching tube and the grid electrode of the third switching tube, and the grid electrode of the seventh switching tube is respectively and electrically connected with the source electrode of the seventh switching tube and the fourth power supply.

9. The motor drive circuit of claim 7, wherein the fourth overshoot suppression module comprises a fourth resistor and an eighth switching tube;

the fourth resistor is electrically connected with the drain electrode of the eighth switching tube and the grid electrode of the fourth switching tube respectively, and the grid electrode of the eighth switching tube and the source electrode of the eighth switching tube are electrically connected and grounded.

10. A motor driver comprising a motor drive circuit according to any one of claims 1 to 9.

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