WO2020191996A1

WO2020191996A1 - Motor driving circuit and system

Info

Publication number: WO2020191996A1
Application number: PCT/CN2019/100993
Authority: WO
Inventors: 赵立群; 吕少波; 陈建群
Original assignee: 广州皓醒湾科技有限公司
Priority date: 2019-03-28
Filing date: 2019-08-16
Publication date: 2020-10-01
Also published as: CN109818533A

Abstract

The present invention relates to the technical field of motor driving, and provides a motor driving circuit and system. The motor driving circuit comprises a forward rotation driving port, a reverse rotation driving port, and first to fourth control circuits. The first control circuit is separately connected to a power supply, the forward rotation driving port, and a first end of a motor to be controlled. The second control circuit is separately connected to the power supply, the reverse rotation driving port, and a second end of the motor to be controlled. The third control circuit is separately connected to the forward rotation driving port, the first end of the motor to be controlled, and a grounding end. The fourth control circuit is separately connected to the reverse rotation driving port, the second end of the motor to be controlled, and the grounding end. When no effective driving signal is inputted, a current on the motor to be controlled is transmitted to the grounding end by means of the third control circuit and the fourth control circuit, so as to stop operating. The third control circuit and the fourth control circuit each comprises resistors and a switch tube. The invention would not cause high-frequency oscillation and noise increase, and alleviates the technical problem in the prior art of high operating noise of a motor driving circuit of an electric toothbrush.

Description

Motor drive circuit and system

Cross references to related applications

This application claims the priority of the Chinese patent application with the application number 201910243365X and the name "Motor Drive Circuit and System" filed with the Chinese Patent Office on March 28, 2019, the entire content of which is incorporated into this application by reference.

Technical field

The present disclosure relates to the field of motor drive technology, and in particular to a motor drive circuit and system.

Background technique

When using ordinary toothbrushes, excessive brushing force or incorrect methods will cause damage to teeth and gums. Studies have shown that electric toothbrushes can reduce the strength of brushing by about 60%, making the process of brushing safer and more effective.

In the prior art, the driving circuit of the motor in the electric toothbrush is shown in FIG. 1. Among them, the drive signal of the motor has a dead time in the process of alternating high and low levels, that is, no drive waveform is output. At this time, the motor stops running, but the current on the path where the motor is located cannot be directly reduced to 0 milliamps (mA), but freewheeling through the diode. This freewheeling method causes the equivalent inductance of the motor to be equivalent to that of the diode The capacitor oscillates at a high frequency, causing machine noise.

In summary, the motor drive circuit of the electric toothbrush in the prior art has a technical problem of large operating noise.

Summary of the invention

In view of this, one of the objectives of the present disclosure is to provide a motor drive circuit and system to alleviate the technical problem of high operating noise of the motor drive circuit of the electric toothbrush in the prior art.

In a first aspect, the present disclosure provides a motor drive circuit, including: a forward drive port, a reverse drive port, a first control circuit, a second control circuit, a third control circuit, and a fourth control circuit;

The first end of the first control circuit is connected to the power supply, the second end of the first control circuit is connected to the forward drive port, and the third end of the first control circuit is connected to the first end of the motor to be controlled. One end connected

The first end of the second control circuit is connected to the power supply, the second end of the second control circuit is connected to the inversion drive port, and the third end of the second control circuit is connected to the standby The second end of the control motor is connected;

The first end of the third control circuit is connected to the forward drive port, the second end of the third control circuit is connected to the first end of the motor to be controlled, and the third end of the third control circuit is connected to the first end of the motor to be controlled. The terminal is connected to the ground terminal;

The first end of the fourth control circuit is connected to the reverse drive port, the second end of the fourth control circuit is connected to the second end of the motor to be controlled, and the third end of the fourth control circuit is The terminal is connected to the ground terminal;

When neither the forward drive port nor the reverse drive port has a valid drive signal input, the first control circuit and the second control circuit are closed, and the current on the motor to be controlled passes through the third The control circuit and the fourth control circuit are transmitted to the ground to stop the motor to be controlled from running, wherein the third control circuit and the fourth control circuit include a resistor and a switch tube.

With reference to the first aspect, the present disclosure provides a first possible implementation manner of the first aspect, wherein the third control circuit and the fourth control circuit do not include diodes.

With reference to the first aspect, the present disclosure provides a second possible implementation manner of the first aspect, wherein the conduction level of the first control circuit and the second control circuit is a first level, and the first The conduction level of the third control circuit and the fourth control circuit is a second level; wherein, one of the first level and the second level is a high level, and the other is a low level.

With reference to the first aspect, the present disclosure provides a third possible implementation manner of the first aspect, wherein, when the forward rotation drive port has a valid drive signal input, and the reverse rotation drive port has no valid drive signal input, The first control circuit and the fourth control circuit are turned on, and the second control circuit and the third control circuit are turned off, so that the motor to be controlled rotates forward;

When the forward drive port has no effective drive signal input and the reverse drive port has an effective drive signal input, the second control circuit and the third control circuit are turned on, and the first control circuit and The fourth control circuit is closed, so that the motor to be controlled reverses;

The effective driving signal is one of the first level and the second level.

With reference to the first aspect, the present disclosure provides a fourth possible implementation manner of the first aspect, wherein the first control circuit includes: a first switch tube, a first resistor, and a second resistor;

Wherein, the source of the first switch tube is respectively connected to the power supply and the first end of the first resistor, and the second end of the first resistor is respectively connected to the first end and the first end of the second resistor. The gate of the first switch tube is connected, and the second end of the second resistor is connected to the forward drive port;

The drain of the first switch tube is connected to the first end of the motor to be controlled.

With reference to the first aspect, the present disclosure provides a fifth possible implementation manner of the first aspect, wherein the second control circuit includes: a second switch tube, a third resistor, and a fourth resistor;

Wherein, the source of the second switch tube is respectively connected to the power supply and the first end of the third resistor, and the second end of the third resistor is respectively connected to the first end and the first end of the fourth resistor. The gate of the second switch tube is connected, and the second end of the fourth resistor is connected to the inversion drive port;

The drain of the second switch tube is connected to the second end of the motor to be controlled.

With reference to the first aspect, the present disclosure provides a sixth possible implementation manner of the first aspect, wherein the third control circuit includes: a third switch tube, a fifth resistor, and a sixth resistor;

Wherein, the first end of the fifth resistor is connected to the forward drive port, and the second end of the fifth resistor is respectively connected to the first end of the sixth resistor and the gate of the third switch tube. Connected, the second end of the sixth resistor is respectively connected to the source and ground of the third switch tube;

The drain of the third switch tube is connected to the first end of the motor to be controlled.

With reference to the first aspect, the present disclosure provides a seventh possible implementation manner of the first aspect, wherein the fourth control circuit includes: a fourth switch tube, a seventh resistor, and an eighth resistor;

Wherein, the first end of the seventh resistor is connected to the inversion drive port, and the second end of the seventh resistor is respectively connected to the first end of the eighth resistor and the gate of the fourth switch tube. Connected, the second end of the eighth resistor is respectively connected to the source and ground of the fourth switch tube;

The drain of the fourth switch tube is connected to the second end of the motor to be controlled.

With reference to the first aspect, the present disclosure provides an eighth possible implementation manner of the first aspect, wherein the first switch tube includes a PMOS tube.

With reference to the first aspect, the present disclosure provides a ninth possible implementation manner of the first aspect, wherein the second switch tube includes a PMOS tube.

With reference to the first aspect, the present disclosure provides a tenth possible implementation manner of the first aspect, wherein the third switch tube includes an NMOS tube.

With reference to the first aspect, the present disclosure provides an eleventh possible implementation manner of the first aspect, wherein the fourth switch tube includes an NMOS tube.

With reference to the first aspect, the present disclosure provides a twelfth possible implementation manner of the first aspect, wherein the effective driving signal is a low level.

With reference to the first aspect, the present disclosure provides a thirteenth possible implementation manner of the first aspect, wherein the effective drive signal is at a high level, and both the first control circuit and the second control circuit adopt NMOS The tube is used as a switch tube, and the third control circuit and the fourth control circuit both use PMOS tubes as the switch tube.

In a second aspect, the present disclosure also provides a motor drive system, the system includes the motor drive circuit described in the above first aspect, and further includes: a motor to be controlled;

The motor to be controlled is connected to the motor drive circuit.

Other features and advantages of the present disclosure will be described in the following specification, and partly become obvious from the specification, or understood by implementing the present disclosure. The purpose and other advantages of the present disclosure are realized and obtained by the structures specifically pointed out in the specification, claims and drawings.

In order to make the above-mentioned objects, features and advantages of the present disclosure more obvious and understandable, preferred embodiments are described in detail below in conjunction with accompanying drawings.

Description of the drawings

In order to more clearly describe the specific embodiments of the present disclosure or the technical solutions in the prior art, the following will briefly introduce the drawings that need to be used in the specific embodiments or the description of the prior art. Obviously, the appendix in the following description The drawings are some embodiments of the present disclosure. For those of ordinary skill in the art, other drawings may be obtained based on these drawings without creative work.

FIG. 1 is a driving circuit of a motor in the prior art provided by the present disclosure;

2 is a schematic diagram of the structure of a motor drive circuit of the present disclosure;

3 is a schematic diagram of circuit connection of a motor drive circuit of the present disclosure;

Fig. 4 is a schematic structural diagram of a motor drive system of the present disclosure.

icon:

1-motor drive circuit; 2-motor to be controlled; 11-first control circuit; 12-second control circuit; 13-third control circuit; 14-fourth control circuit.

detailed description

In order to make the objectives, technical solutions and advantages of the present disclosure clearer, the technical solutions of the present disclosure will be described clearly and completely with reference to the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present disclosure, but not all of them. Examples. Based on the embodiments in the present disclosure, all other embodiments obtained by those of ordinary skill in the art without creative work shall fall within the protection scope of the present disclosure.

Fig. 2 is a schematic structural diagram of a motor drive circuit provided according to the present disclosure. As shown in FIG. 2, the motor drive circuit includes: a forward drive port INA, a reverse drive port INB, a first control circuit 11, a second control circuit 12, a third control circuit 13, and a fourth control circuit 14.

The motor to be controlled includes two connection terminals. The first control circuit 11, the second control circuit 12, the third control circuit 13, and the fourth control circuit 14 each include three connection terminals.

The first terminal of the first control circuit 11 is connected to the power supply VBAT, the second terminal of the first control circuit 11 is connected to the forward drive port INA, and the third terminal of the first control circuit 11 is connected to the first terminal of the motor to be controlled.端连接。 End connection.

The first end of the second control circuit 12 is connected to the power supply VBAT, the second end of the second control circuit 12 is connected to the inversion drive port INB, and the third end of the second control circuit 12 is connected to the second end of the motor to be controlled .

The first end of the third control circuit 13 is connected to the forward drive port INA, the second end of the third control circuit 13 is connected to the first end of the motor to be controlled, and the third end of the third control circuit 13 is connected to the ground end.

The first end of the fourth control circuit 14 is connected to the inversion drive port INB, the second end of the fourth control circuit 14 is connected to the second end of the motor to be controlled, and the third end of the fourth control circuit is connected to the ground end.

When the motor drive waveform is in the dead time period, that is, when there is no valid drive signal input to the forward drive port INA and the reverse drive port INB, the first control circuit 11 and the second control circuit 12 are closed, and the motor The current is transmitted to the ground through the third control circuit 13 and the fourth control circuit 14 to stop the motor to be controlled. The third control circuit 13 and the fourth control circuit 14 include resistors and switch tubes, but do not include diodes.

Specifically, the motor drive circuit provided by the present disclosure is specifically composed of a first control circuit 11, a second control circuit 12, a third control circuit 13, a fourth control circuit 14, a forward rotation drive port INA and a reverse rotation drive port INB.

According to the above circuit connection mode, the forward drive port INA is connected to the second end of the first control circuit 11 and the first end of the third control circuit 13 respectively, and the reverse drive port INB is connected to the first end of the second control circuit 12 respectively. The second terminal is connected to the first terminal of the fourth control circuit 14, the first terminal of the first control circuit 11 and the first terminal of the second control circuit 12 are connected to the power supply VBAT, and the third terminal of the third control circuit 13 is connected to the fourth terminal. The third end of the control circuit 14 is grounded, the first end of the motor to be controlled is connected to the third end of the first control circuit 11 and the second end of the third control circuit 13 respectively, and the second end of the motor to be controlled is connected to the second The third terminal of the control circuit 12 is connected to the second terminal of the fourth control circuit 14. The specific circuit structure of each control circuit will be described in detail below.

In this embodiment, when there is no valid drive signal input at the forward drive port INA and the reverse drive port INB, the third control circuit 13 and the fourth control circuit 14 will be in a conducting state, and the first end of the waiting motor will pass The third control circuit 13 is grounded, and the second end of the motor to be controlled is grounded through the fourth control circuit 14, so that the inductive current in the motor to be controlled is released through the ground loop, and the motor stops running.

The third control circuit 13 and the fourth control circuit 14 of the present disclosure are both composed of resistors and switch tubes, and do not include diodes that can oscillate at high frequency with the equivalent inductance of the motor. Therefore, the motor will not be caused by high frequency during operation. Noise caused by oscillations.

When the forward drive port INA inputs a valid drive signal and the reverse drive port INB has no valid drive signal input, the third control circuit 13 is closed, the first control circuit 11 is turned on, the fourth control circuit 14 is turned on, and the second control circuit 12 is closed, and the current flows from the first end of the motor to be controlled to the second end of the motor to be controlled, so that the motor to be controlled realizes forward rotation.

When the reverse drive port INB inputs a valid drive signal and the forward drive port INA has no valid drive signal input, the fourth control circuit 14 is turned off, the second control circuit 12 is turned on, the third control circuit 13 is turned on, and the first control circuit 11 is closed, and current flows from the second end of the motor to be controlled to the first end of the motor to be controlled, so that the motor to be controlled can reverse.

In the motor drive circuit of the electric toothbrush in the prior art, when there is no drive signal input, the diode freewheeling method is used to gradually reduce the current in the motor to 0mA, and the equivalent inductance of the motor in this circuit structure will be the same as that of the diode. The equivalent capacitor oscillates at a high frequency, causing machine noise. Compared with the motor drive circuit in the prior art, the motor drive circuit provided by the present disclosure, when there is no valid drive signal input at the forward drive port INA and the reverse drive port INB, the current on the motor to be controlled will pass through the third The control circuit 13 and the fourth control circuit 14 are transmitted to the ground terminal to stop the motor to be controlled. Since the third control circuit 13 and the fourth control circuit 14 include resistors and switch tubes, there are no diodes, so high frequency will not be caused. Oscillation increases operating noise and alleviates the technical problem of high operating noise of the motor drive circuit of the electric toothbrush in the prior art.

In this embodiment, the conduction levels of the first control circuit 11 and the second control circuit 12 are the same, and both are the first level. The conduction levels of the third control circuit 13 and the fourth control circuit 14 are the same, and both are the second level. Among them, one of the first level and the second level is a high level, and the other is a low level. In this way, the motor to be controlled can realize forward or reverse rotation by controlling the drive signals input to the forward drive port INA and the reverse drive port INB.

The foregoing is a brief description of the composition structure of the motor drive circuit of the present disclosure, and the specific circuit structure of the first control circuit 11 is described in detail below.

In an alternative embodiment, referring to FIG. 3, the first control circuit 11 includes a first switch tube Q1, a first resistor R1, and a second resistor R2, and the first switch tube Q1 includes a PMOS tube.

Wherein, the source S of the first switching tube Q1 is respectively connected to the power supply VBAT and the first end of the first resistor R1, and the second end of the first resistor R1 is connected to the first end of the second resistor R2 and the first switching tube respectively. The gate G of Q1 is connected, and the second end of the second resistor R2 is connected to the forward drive port INA. The drain D of the first switch Q1 is connected to the first terminal of the motor to be controlled.

For ease of understanding, the first control circuit 11 when the first switch tube Q1 is a PMOS tube will be described in detail below. According to the above circuit connection relationship, the voltage of the gate G of the first switch Q1 is the node voltage of the connection node between the second end of the first resistor R1 and the first end of the second resistor R2, and the first switch Q1 The source S and the first end of the first resistor R1 are both connected to the power supply VBAT. The second end of the second resistor R2 is connected to the forward drive port INA. When the forward drive port INA inputs a high level, the first switch The tube Q1 is turned off, that is, the first control circuit 11 is turned off. At this time, the third control circuit 13 is turned on, that is, the high level is an invalid drive signal, and the low level is an effective drive signal.

In order to realize the forward rotation of the motor to be controlled, the forward drive port INA should input a valid drive signal (low level), and the reverse drive port INB should input an invalid drive signal (high level). At this time, the fourth control circuit 14 is turned on , The second control circuit 12 and the third control circuit 13 are turned off, and the gate-source voltage of the first switch tube Q1 meets the PMOS conduction requirement through the voltage division of the first resistor R1 and the second resistor R2, and the first switch tube Q1 Conduction, thereby turning on the first control circuit 11, the coil current of the motor to be controlled flows from the first end of the motor to be controlled to the second end of the motor to be controlled. The motor to be controlled realizes forward rotation.

The specific structure and working conditions of the first control circuit 11 are described in detail above, and the specific structure of the second control circuit 12 is described in detail below.

In an alternative embodiment, referring to FIG. 3, the second control circuit 12 includes a second switch tube Q2, a third resistor R3, and a fourth resistor R4, and the second switch tube Q2 includes a PMOS tube.

Wherein, the source S of the second switch tube Q2 is connected to the power supply VBAT and the first end of the third resistor R3, and the second end of the third resistor R3 is connected to the first end of the fourth resistor R4 and the second switch tube respectively. The gate G of Q2 is connected, and the second end of the fourth resistor R4 is connected to the inversion drive port INB. The drain D of the second switch Q2 is connected to the second end of the motor to be controlled.

For ease of understanding, the second control circuit 12 when the second switching tube Q2 is a PMOS tube will be described in detail below. According to the above circuit connection relationship, the voltage of the gate G of the second switching tube Q2 is the third resistor R3. The second end of the second end of the fourth resistor R4 and the first end of the node voltage, and the source S of the second switch tube Q2 and the first end of the third resistor R3 are connected to the power supply VBAT, the second end of the fourth resistor R4 and The inversion drive port INB is connected. When the inversion drive port INB inputs a high level, the second switch Q2 is turned off, that is, the second control circuit 12 is turned off. At this time, the fourth control circuit 14 is turned on, that is, high level. It is an invalid drive signal, and the low level is an effective drive signal.

In order to realize the reverse rotation of the motor to be controlled, the reverse drive port INB should input an effective drive signal (low level), and the forward drive port INA should input an invalid drive signal (high level). At this time, the third control circuit 13 is turned on , The first control circuit 11 and the fourth control circuit 14 are closed, and the gate-source voltage of the second switching tube Q2 meets the PMOS conduction requirement through the voltage division of the third resistor R3 and the fourth resistance R4, and the second switching tube Q2 Turning on, thereby turning on the second control circuit 12, the current flows from the second end of the motor to be controlled to the first end of the motor to be controlled, and the motor to be controlled realizes reverse rotation.

The specific structure and operating conditions of the second control circuit 12 are described in detail above, and the specific structure of the third control circuit 13 is described in detail below.

In an alternative embodiment, referring to FIG. 3, the third control circuit 13 includes: a third switch tube Q3, a fifth resistor R5, and a sixth resistor R6; the third switch tube Q3 includes an NMOS tube.

The first end of the fifth resistor R5 is connected to the forward drive port INA, the second end of the fifth resistor R5 is respectively connected to the first end of the sixth resistor R6 and the gate G of the third switch Q3, and the sixth The second end of the resistor R6 is respectively connected to the source S and the ground end of the third switch tube Q3;

The drain D of the third switch Q3 is connected to the first end of the motor to be controlled.

For ease of understanding, the third control circuit 13 when the third switching tube Q3 is an NMOS tube will be described in detail below. According to the above circuit connection relationship, the voltage of the gate G of the third switching tube Q3 is the fifth resistor R5. The node voltage of the connection node between the second end of the sixth resistor R6 and the first end of the sixth resistor R6, and the first end of the fifth resistor R5 is connected to the forward drive port INA, the source S of the third switch Q3 and the sixth resistor The second end of R6 is grounded. When the forward drive port INA inputs a high level, the voltage division of the fifth resistor R5 and the sixth resistor R6 makes the gate-source voltage of the third switch tube Q3 meet the NMOS conduction requirement. The three switch Q3 is turned on, that is, the third control circuit 13 is turned on. At this time, the first control circuit 11 is turned off, that is, the high level is an invalid drive signal, and the low level is an effective drive signal.

At this time, in order to drive the motor to be controlled to reverse, the reverse drive port INB should input a valid drive signal (low level) to turn off the fourth control circuit 14 and turn on the second control circuit 12. The second end of the motor flows to the first end of the motor to be controlled, and the motor to be controlled realizes reverse rotation.

The specific structure and working conditions of the third control circuit 13 are described in detail above, and the specific structure of the fourth control circuit 14 is described in detail below.

In an alternative embodiment, referring to FIG. 3, the fourth control circuit 14 includes a fourth switch tube Q4, a seventh resistor R7, and an eighth resistor R8, and the fourth switch tube Q4 includes an NMOS tube.

The first end of the seventh resistor R7 is connected to the inversion drive port INB, the second end of the seventh resistor R7 is respectively connected to the first end of the eighth resistor R8 and the gate G of the fourth switch tube Q4, and the eighth The second end of the resistor R8 is respectively connected to the source S and the ground end of the fourth switch tube Q4. The drain D of the fourth switch tube Q4 is connected to the second end of the motor to be controlled.

For ease of understanding, the fourth control circuit 14 when the fourth switching tube Q4 is an NMOS tube will be described in detail below. According to the above circuit connection relationship, the voltage of the gate G of the fourth switching tube Q4 is the seventh resistor R7. The second terminal of the seventh resistor R8 is connected to the node voltage of the first terminal of the eighth resistor R8, and the first terminal of the seventh resistor R7 is connected to the inversion drive port INB. The source S of the fourth switch Q4 and the first terminal of the eighth resistor R8 The two ends are grounded. When the inversion drive port INB inputs a high level, the gate-source voltage of the fourth switch tube Q4 reaches the NMOS conduction requirement through the voltage division of the seventh resistor R7 and the eighth resistor R8, and the fourth switch tube Q4 is turned on, that is, the fourth control circuit 14 is turned on. At this time, the second control circuit 12 is turned off, that is, the high level is an invalid drive signal, and the low level is an effective drive signal.

At this time, in order to drive the motor to be controlled forward, the forward drive port INA should input a valid drive signal (low level) to turn off the third control circuit 13 and turn on the first control circuit 11. At this time, the motor to be controlled The coil current flows from the first end of the motor to be controlled to the second end of the motor to be controlled, and the motor to be controlled realizes forward rotation.

In summary, in the motor drive circuit provided by the present disclosure, the alternating low-level (effective drive signal) input of the forward drive port INA and the reverse drive port INB realizes the forward drive and reverse drive of the motor to be controlled. To make the electric toothbrush work, each control circuit includes a switch tube and a resistor, and there is no diode connected in parallel with the switch tube, which alleviates the technical problem of high operating noise of the motor drive circuit in the prior art.

In addition, because no high voltage is coupled between the drain and source of the switch tube, the reliability of the operation of the switch tube is greatly improved. Further, the forward drive port INA is connected to the first control circuit 11 and the third control circuit 13 respectively. , And it is set that the first control circuit 11 and the third control circuit 13 cannot be turned on at the same time, which further ensures the safe operation of the circuit. The reverse driving port INB is also the same principle, which will not be repeated here.

In order to facilitate understanding, only the first switching tube Q1 and the second switching tube Q2 are PMOS tubes, and the third switching tube Q3 and the fourth switching tube Q4 are NMOS tubes. The user can also refer to the specific situation. Use switch tubes that can achieve the same function. For example, PMOS tubes can be replaced by PNP transistors, and NMOS tubes can be replaced by NPN transistors. The present disclosure does not specifically limit it. The motor drive circuit of the present disclosure can also be applied to other fields. This disclosure does not apply to this circuit. The implementation area is restricted.

In other embodiments, the first switching tube Q1 and the second switching tube Q2 may be NMOS tubes, and the third switching tube Q3 and the fourth switching tube Q4 may be PMOS tubes. At this time, the effective driving signal is high. The invalid drive signal is low.

Correspondingly, a high level can be input to the forward drive port INA, and a low level can be input to the reverse drive port INB, so that the first switching tube Q1 and the fourth switching tube Q4 are turned on, and the second switching tube Q2 and the third switching tube Q2 are turned on. The switch Q3 is closed. That is, the first control circuit 11 and the fourth control circuit 14 are turned on, and the second control circuit 12 and the third control circuit 14 are turned off, thereby realizing the forward rotation of the motor to be controlled.

You can input a low level to the forward drive port INA and a high level to the reverse drive port INB, so that the first switching tube Q1 and the fourth switching tube Q4 are turned off, and the second switching tube Q2 and the third switching tube Q3 are turned off . That is, the first control circuit 11 and the fourth control circuit 14 are turned off, and the second control circuit 12 and the third control circuit 13 are turned on, thereby realizing the reverse rotation of the motor to be controlled.

The present disclosure also provides a motor drive system. Referring to FIG. 4, the motor drive system includes the above-mentioned motor drive circuit 1 and the motor 2 to be controlled, wherein the motor 2 to be controlled is connected to the motor drive circuit 1.

The connection relationship between the motor 2 to be controlled and the motor drive circuit 1 has been described in detail above, and how the motor drive circuit 1 controls the motor 2 to be controlled to perform forward and reverse rotation. For details, please refer to the above description. Repeat it again.

Unless specifically stated otherwise, the relative steps, numerical expressions and numerical values of components and steps set forth in these embodiments do not limit the scope of the present disclosure.

In all the examples shown and described herein, any specific value should be interpreted as merely exemplary, rather than as a limitation, and therefore, other examples of the exemplary embodiment may have different values.

It should be noted that similar reference numerals and letters indicate similar items in the following figures. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

The flowcharts and block diagrams in the drawings show the possible implementation architecture, functions, and operations of the system, method, and computer program product according to multiple embodiments of the present disclosure. In this regard, each block in the flowchart or block diagram may represent a module, program segment, or part of the code, and the module, program segment, or part of the code contains one or more functions for realizing the specified logical function. Executable instructions. It should also be noted that, in some alternative implementations, the functions marked in the block may also occur in a different order from the order marked in the drawings. For example, two consecutive blocks can actually be executed in parallel, or they can sometimes be executed in the reverse order, depending on the functions involved. It should also be noted that each block in the block diagram and/or flowchart, and the combination of the blocks in the block diagram and/or flowchart, can be implemented by a dedicated hardware-based system that performs the specified functions or actions Or it can be realized by a combination of dedicated hardware and computer instructions.

In addition, in the description of the present disclosure, unless otherwise clearly defined and defined, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it may be a fixed connection or a detachable connection, or Integrally connected; it can be a mechanical connection or an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, and it can be the internal communication between two components. For those of ordinary skill in the art, the specific meaning of the above-mentioned terms in the present disclosure can be understood in specific situations.

In the description of the present disclosure, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. The indicated orientation or positional relationship is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present disclosure and simplifying the description, and does not indicate or imply that the pointed device or element must have a specific orientation or a specific orientation. The structure and operation cannot therefore be construed as limiting the present disclosure. In addition, the terms "first", "second", and "third" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance.

Those skilled in the art can clearly understand that, for the convenience and conciseness of description, the specific working process of the above-described system, device, and unit can refer to the corresponding process in the foregoing method embodiment, which will not be repeated here.

In the several embodiments provided in this application, it should be understood that the disclosed system, device, and method may be implemented in other ways. The device embodiments described above are merely illustrative. For example, the division of the units is only a logical function division, and there may be other divisions in actual implementation. For example, multiple units or components may be combined or It can be integrated into another system, or some features can be ignored or not implemented. In addition, the displayed or discussed mutual coupling or direct coupling or communication connection may be through some communication interfaces, indirect coupling or communication connection of the devices or units, and may be in electrical, mechanical or other forms.

The units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the objectives of the solutions of the embodiments.

In addition, the functional units in the various embodiments of the present disclosure may be integrated into one processing unit, or each unit may exist alone physically, or two or more units may be integrated into one unit.

If the function is implemented in the form of a software functional unit and sold or used as an independent product, it may be stored in a nonvolatile computer readable storage medium executable by a processor. Based on this understanding, the technical solution of the present disclosure essentially or the part that contributes to the prior art or the part of the technical solution can be embodied in the form of a software product. The computer software product is stored in a storage medium, including Several instructions are used to make a computer device (which may be a personal computer, a server, or a network device, etc.) execute all or part of the steps of the methods described in the various embodiments of the present disclosure. The aforementioned storage media include: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), magnetic disk or optical disk and other media that can store program code .

Finally, it should be noted that the above-mentioned embodiments are only specific implementations of the present disclosure, which are used to illustrate the technical solutions of the present disclosure, but not to limit it. The protection scope of the present disclosure is not limited thereto, although referring to the foregoing The embodiments give a detailed description of the present disclosure, and those of ordinary skill in the art should understand that any person skilled in the art can still modify the technical solutions described in the foregoing embodiments within the technical scope disclosed in the present disclosure. Or it can be easily conceived of changes, or equivalent replacement of some of the technical features; and these modifications, changes or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the present disclosure, and should be covered by the protection of the present disclosure Within range. Therefore, the protection scope of the present disclosure should be subject to the protection scope of the claims.

Industrial applicability

The motor drive circuit and system provided by the present disclosure can transmit the inductance current of the motor to be controlled to the ground through the third control circuit and the fourth control circuit when there is no effective drive signal input at the forward drive port and the reverse drive port. The problem of large noise caused by the freewheeling of the inductance current of the motor through the diode is avoided.

Claims

A motor drive circuit, characterized in that it is applied to an electric toothbrush, and includes: a forward rotation drive port, a reverse rotation drive port, a first control circuit, a second control circuit, a third control circuit, and a fourth control circuit;

The first end of the first control circuit is connected to the power supply, the second end of the first control circuit is connected to the forward drive port, and the third end of the first control circuit is connected to the first end of the motor to be controlled. One end connected

The first end of the second control circuit is connected to the power supply, the second end of the second control circuit is connected to the inversion drive port, and the third end of the second control circuit is connected to the standby The second end of the control motor is connected;

The first end of the third control circuit is connected to the forward drive port, the second end of the third control circuit is connected to the first end of the motor to be controlled, and the third end of the third control circuit is connected to the first end of the motor to be controlled. The terminal is connected to the ground terminal;

The first end of the fourth control circuit is connected to the reverse drive port, the second end of the fourth control circuit is connected to the second end of the motor to be controlled, and the third end of the fourth control circuit is The terminal is connected to the ground terminal;

When neither the forward drive port nor the reverse drive port has a valid drive signal input, the first control circuit and the second control circuit are closed, and the current on the motor to be controlled passes through the third The control circuit and the fourth control circuit are transmitted to the ground terminal to stop the motor to be controlled, wherein the third control circuit and the fourth control circuit include a resistor and a switch tube.
The motor drive circuit according to claim 1, wherein the third control circuit and the fourth control circuit do not include diodes.
The motor drive circuit according to claim 1 or 2, wherein the conduction level of the first control circuit and the second control circuit is a first level, and the third control circuit and the The conduction level of the fourth control circuit is a second level; wherein, one of the first level and the second level is a high level, and the other is a low level.
The motor drive circuit of claim 3, wherein when the forward drive port has a valid drive signal input, and the reverse drive port has no effective drive signal input, the first control circuit and the The fourth control circuit is turned on, and the second control circuit and the third control circuit are turned off, so that the motor to be controlled rotates forward;

When the forward drive port has no effective drive signal input and the reverse drive port has an effective drive signal input, the second control circuit and the third control circuit are turned on, and the first control circuit and The fourth control circuit is closed, so that the motor to be controlled reverses;

The effective driving signal is one of the first level and the second level.
The motor drive circuit according to any one of claims 1-4, wherein the first control circuit comprises: a first switch tube, a first resistor, and a second resistor;

Wherein, the source of the first switch tube is respectively connected to the power supply and the first end of the first resistor, and the second end of the first resistor is respectively connected to the first end and the first end of the second resistor. The gate of the first switch tube is connected, and the second end of the second resistor is connected to the forward drive port;

The drain of the first switch tube is connected to the first end of the motor to be controlled.
The motor drive circuit according to any one of claims 1-5, wherein the second control circuit comprises: a second switch tube, a third resistor, and a fourth resistor;

Wherein, the source of the second switch tube is respectively connected to the power supply and the first end of the third resistor, and the second end of the third resistor is respectively connected to the first end and the first end of the fourth resistor. The gate of the second switch tube is connected, and the second end of the fourth resistor is connected to the inversion drive port;

The drain of the second switch tube is connected to the second end of the motor to be controlled.
The motor drive circuit according to any one of claims 1-6, wherein the third control circuit comprises: a third switch tube, a fifth resistor, and a sixth resistor;

Wherein, the first end of the fifth resistor is connected to the forward drive port, and the second end of the fifth resistor is respectively connected to the first end of the sixth resistor and the gate of the third switch tube. Connected, the second end of the sixth resistor is connected to the source and the ground of the third switch tube;

The drain of the third switch tube is connected to the first end of the motor to be controlled.
The motor drive circuit according to any one of claims 1-7, wherein the fourth control circuit comprises: a fourth switch tube, a seventh resistor, and an eighth resistor;

Wherein, the first end of the seventh resistor is connected to the inversion drive port, and the second end of the seventh resistor is respectively connected to the first end of the eighth resistor and the gate of the fourth switch tube. Connected, the second end of the eighth resistor is connected to the source and the ground of the fourth switch tube;

The drain of the fourth switch tube is connected to the second end of the motor to be controlled.
The motor drive circuit according to claim 5, wherein the first switch tube comprises: a PMOS tube.
The motor drive circuit according to claim 6, wherein the second switch tube comprises a PMOS tube.
The motor drive circuit according to claim 7, wherein the third switch tube comprises: an NMOS tube.
The motor drive circuit according to claim 8, wherein the fourth switch tube comprises: an NMOS tube.
The motor drive circuit according to any one of claims 9-12, wherein the effective drive signal is a low level.
The motor drive circuit according to any one of claims 3-8, wherein the effective drive signal is a high level, and the first control circuit and the second control circuit both use NMOS transistors as switches Tube, the third control circuit and the fourth control circuit both use PMOS tubes as switching tubes.
A motor drive system, the system comprising the motor drive circuit of any one of claims 1 to 14, and further comprising: a motor to be controlled;

The motor to be controlled is connected to the motor drive circuit.