WO2023138161A1 - Low-side driving circuit, electronic device having same, and vehicle - Google Patents

Abstract

The present disclosure relates to the technical field of electronic appliances. Provided are a low-side driving circuit, an electronic device having same and a vehicle. The low-side driving circuit (100) comprises a switch module (101), a sampling module (102), a current detection module (103) and a current control module (104). The sampling module (102) is configured to convert an output current of a load into a first voltage signal and then output the first voltage signal to the current detection module (103); the current detection module (103) is configured to convert the first voltage signal into a second voltage signal and then output the second voltage signal to a controller, so as to instruct the controller to output, according to the second voltage signal, a pulse width modulation signal to the current control module (104); and the current control module (104) is configured to control, according to the pulse width modulation signal output by the controller, the on-off duration of the switch module (101) so as to adjust the magnitude of the output current of the load.

Description

Low-side driving circuit and electronic equipment and vehicle having same

Cross References to Related Applications

This disclosure claims the priority of the Chinese patent application with application number 202210080165.9 filed on January 24, 2022, entitled "Low-side drive circuit and electronic equipment and vehicle with same", the entire content of which is incorporated in this disclosure by reference.

technical field

The present disclosure relates to the technical field of electronic appliances, in particular to a low-side driving circuit and electronic equipment and vehicles having the same.

Background technique

Cars are an indispensable means of transportation in life, bringing great convenience to people's daily travel, and various devices installed on cars can meet different needs for use.

At present, the low-side driving circuit in the related art uses a functional chip to realize corresponding control, but this method is expensive to manufacture, is not conducive to wide application, and severely limits the mass production of automobiles.

public content

Based on this, it is necessary to provide a low-side driving circuit and an electronic device and a vehicle having it, which can achieve the same function as a functional chip while greatly reducing manufacturing costs.

In a first aspect, an embodiment of the present disclosure provides a low-side drive circuit, the circuit includes a switch module, a sampling module, a current detection module, and a current control module;

The first end of the switch module is connected to the load, the second end of the switch module is respectively connected to the first end of the sampling module and the first end of the current detection module, the second end of the sampling module is grounded, the second end of the current detection module is connected to the first end of the controller, the first end of the current control module is connected to the second end of the controller, and the second end of the current control module is connected to the third end of the switch module;

The sampling module is configured to convert the output current of the load into a first voltage signal and output it to the current detection module;

The current detection module is configured to convert the first voltage signal into a second voltage signal and output it to the controller, so as to instruct the controller to output a pulse width modulation signal to the current control module according to the second voltage signal;

The current control module is configured to control the on-off duration of the switch module according to the pulse width modulation signal output by the controller, so as to adjust the output current of the load.

Optionally, in some embodiments of the present disclosure, the switch module includes a switch tube;

The first end of the switch tube is connected to the load, the second end of the switch tube is respectively connected to the first end of the sampling module and the first end of the current detection module, and the third end of the switch tube is connected to the second end of the current control module.

Optionally, in some embodiments of the present disclosure, the circuit further includes a first diode, the anode of the first diode is connected to the first end of the switch transistor, and the cathode of the first diode is connected to the output end of the high-side driving circuit.

Optionally, in some embodiments of the present disclosure, the switch module further includes a first transistor, a second transistor, a first resistor, and a second resistor;

The second end of the current control module is respectively connected to the base of the first triode and the base of the second triode, the collector of the second triode is grounded, the emitter of the second triode is connected to the third end of the switch, the emitter of the first triode is connected to the first end of the first resistor, the second end of the first resistor is connected to the third end of the switch, the collector of the first triode is connected to the positive pole of the power supply, the first end of the second resistor is connected to the third end of the switch, and the second end of the second resistor is grounded.

Optionally, in some embodiments of the present disclosure, the current detection module includes an amplification unit;

The first end of the amplifying unit is respectively connected to the second end of the switch module and the first end of the sampling module, the second end of the amplifying unit is connected to the first end of the controller, and the third end of the amplifying unit is connected to the second end of the sampling module;

The amplifying unit is configured to convert the first voltage signal to obtain the second voltage signal and output it to the controller.

Optionally, in some embodiments of the present disclosure, the amplifying unit includes an operational amplifier, a third resistor, a fourth resistor, and a fifth resistor;

The first terminal of the third resistor is respectively connected to the second terminal of the switch module and the first terminal of the sampling module, the second terminal of the third resistor is connected to the positive input terminal of the operational amplifier, the first terminal of the fourth resistor is connected to the second terminal of the sampling module, the second terminal of the fourth resistor is respectively connected to the negative input terminal of the operational amplifier and the output terminal of the operational amplifier, the output terminal of the operational amplifier is connected to the first terminal of the fifth resistor, and the second terminal of the fifth resistor is connected to the first terminal of the controller.

Optionally, in some embodiments of the present disclosure, the amplifying unit further includes a sixth resistor, a seventh resistor, a first capacitor, a second capacitor, and a third capacitor;

The first terminal of the sixth resistor is connected to the second terminal of the third resistor, the second terminal of the sixth resistor is grounded, the first terminal of the first capacitor is connected to the second terminal of the third resistor, the second terminal of the first capacitor is grounded, the first terminal of the seventh resistor is connected to the negative input terminal of the operational amplifier, the second terminal of the seventh resistor is connected to the output terminal of the operational amplifier, the first terminal of the second capacitor is connected to the first terminal of the seventh resistor, the second terminal of the second capacitor is connected to the second terminal of the seventh resistor, the first terminal of the third capacitor is connected to the second terminal of the fifth resistor, and the second terminal of the third capacitor grounded.

Optionally, in some embodiments of the present disclosure, the current detection module further includes a diagnosis unit;

The first terminal of the diagnostic unit is connected to the output terminal of the high-side drive circuit, and the second terminal of the diagnostic unit is connected to the first terminal of the switch module;

The diagnosis unit is configured to output a voltage signal, so that the controller recognizes a circuit operation state according to the voltage signal.

Optionally, in some embodiments of the present disclosure, the operating state of the circuit includes any one of a normal connection between the low-side driving circuit and the load, an open circuit between the low-side driving circuit and the load, and a short circuit between the low-side driving circuit and the load;

Wherein, in the case of the open circuit or the short circuit, the current control module controls the switch module to switch to an off state, and reconnects the switch module.

Optionally, in some embodiments of the present disclosure, the diagnostic unit includes an eighth resistor, a first end of the eighth resistor is connected to the output end of the high-side driving circuit, and a second end of the eighth resistor is connected to the first end of the switch module.

Optionally, in some embodiments of the present disclosure, the current control module includes a control unit and a startup unit;

The first terminal of the control unit is connected to the second terminal of the controller, the second terminal of the control unit is connected to the first terminal of the starting unit, and the second terminal of the starting unit is connected to the third terminal of the switch module;

The control unit is configured to receive the pulse width modulation signal output by the controller, and the starting unit is configured to switch on and off according to the pulse width modulation signal, so as to control the on-off duration of the switch module.

Optionally, in some embodiments of the present disclosure, the control unit includes a band-stop transistor and a ninth resistor, and the startup unit includes a tenth resistor, a third transistor, an eleventh resistor, and a twelfth resistor;

The base of the band-stop transistor is connected to the second end of the controller, the emitter of the band-stop transistor is grounded, the collector of the band-stop transistor is connected to the first end of the ninth resistor, the second end of the ninth resistor is respectively connected to the first end of the tenth resistor and the base of the third transistor, the emitter of the third transistor and the second end of the tenth resistor are connected to the positive pole of the power supply, the collector of the third transistor is connected to the first end of the eleventh resistor, and the second end of the eleventh resistor is respectively connected to the switch module. The third end is connected to the first end of the twelfth resistor, and the second end of the twelfth resistor is grounded.

Optionally, in some embodiments of the present disclosure, the control unit includes a thirteenth resistor, a fourteenth resistor, a fifteenth resistor, and a fourth triode, and the startup unit includes a tenth resistor, a third triode, an eleventh resistor, and a twelfth resistor;

The first end of the thirteenth resistor is connected to the second end of the controller, the second end of the thirteenth resistor is respectively connected to the first end of the fourteenth resistor and the base of the fourth transistor, the second end of the fourteenth resistor is grounded, the emitter of the fourth transistor is connected to the first end of the fifteenth resistor, the second end of the fifteenth resistor is grounded, the collector of the fourth transistor is respectively connected to the first end of the tenth resistor and the base of the third transistor, the emitter of the third transistor and the second end of the tenth resistor are connected to The positive pole of the power supply is connected, the collector of the third triode is connected to the first end of the eleventh resistor, the second end of the eleventh resistor is respectively connected to the third end of the switch module and the first end of the twelfth resistor, and the second end of the twelfth resistor is grounded.

Optionally, in some embodiments of the present disclosure, the control unit further includes a second diode and a third diode, and the startup unit further includes a fourth diode;

The anode of the second diode is connected to the second end of the controller, the cathode of the second diode is connected to the output end of the power management chip, the anode of the third diode is grounded, the cathode of the third diode is connected to the anode of the second diode, the anode of the fourth diode is connected to the second end of the twelfth resistor, and the cathode of the fourth diode is connected to the first end of the twelfth resistor.

Optionally, in some embodiments of the present disclosure, the circuit further includes an overcurrent protection module;

The first end of the overcurrent protection module is connected to the first end of the sampling module, the second end of the overcurrent protection module is connected to the second end of the sampling module, and the third end of the overcurrent protection module is connected to the third end of the switch module;

The overcurrent protection module is configured to convert the first voltage signal into a third voltage signal when receiving the first voltage signal output by the sampling module is greater than a preset voltage threshold, so that the switch module is continuously in an off state.

Optionally, in some embodiments of the present disclosure, the overcurrent protection module includes a first level conversion unit, a second level conversion unit, and a third level conversion unit;

The first end of the sampling module is connected to the first level conversion unit, the first level conversion unit is connected to the second level conversion unit, the second level conversion unit is connected to the third level conversion unit, and the third level conversion unit is connected to the third end of the switch module;

The first level conversion unit is configured to convert the first voltage signal into a fourth voltage signal, the second level conversion unit is configured to convert the fourth voltage signal into a fifth voltage signal and then output to the first level conversion unit and the third level conversion unit, the third level conversion unit is configured to convert the fifth voltage signal into the third voltage signal, and the first level conversion unit is further configured to convert the fifth voltage signal into the fourth voltage signal when the first voltage signal is not received.

Optionally, in some embodiments of the present disclosure, the first level conversion unit includes a sixteenth resistor, a seventeenth resistor, an eighteenth resistor, and a fifth transistor, the second level conversion unit includes a sixth transistor and a nineteenth resistor, and the third level conversion unit includes a twentieth resistor and a seventh transistor;

The first end of the sixteenth resistor is connected to the first end of the sampling module, the second end of the sixteenth resistor is respectively connected to the base of the fifth triode and the first end of the eighteenth resistor, the emitter of the fifth triode is connected to the second end of the sampling module, the collector of the fifth triode is respectively connected to the first end of the seventeenth resistor and the first end of the nineteenth resistor, the second end of the seventeenth resistor is connected to the positive pole of the power supply, the second end of the nineteenth resistor is connected to the base of the sixth triode, the The emitter is connected to the third end of the current control module, the collector of the sixth triode is respectively connected to the second end of the eighteenth resistor and the first end of the twentieth resistor, the second end of the twentieth resistor is connected to the base of the seventh triode, the emitter of the seventh triode is connected to the second end of the sampling module, and the collector of the seventh triode is connected to the third end of the switch module.

Optionally, in some embodiments of the present disclosure, the second level conversion unit further includes a fifth diode, the anode of the fifth diode is connected to the third terminal of the current control module, and the cathode of the fifth diode is connected to the emitter of the sixth transistor.

Optionally, in some embodiments of the present disclosure, the overcurrent protection module further includes a voltage limiting unit;

The first terminal of the voltage limiting unit is connected to the second terminal of the second level conversion unit, the second terminal of the voltage limiting unit is connected to the third terminal of the controller, the third terminal of the voltage limiting unit is grounded, the fourth terminal of the voltage limiting unit is connected to the output terminal of the power management chip, and the fifth terminal of the voltage limiting unit is grounded;

The voltage limiting unit is configured to detect the change of the first voltage signal, and divide the voltage to protect the port of the controller.

Optionally, in some embodiments of the present disclosure, the voltage limiting unit includes a twenty-first resistor, a twenty-second resistor, a twenty-third resistor, a sixth diode, and a seventh diode;

The first end of the twenty-first resistor is connected to the second end of the second level conversion unit, the second end of the twenty-first resistor is respectively connected to the first end of the twenty-second resistor and the anode of the sixth diode, the cathode of the sixth diode is connected to the output end of the power management chip, the cathode of the seventh diode is connected to the anode of the sixth diode, the anode of the seventh diode is grounded, the second end of the twenty-second resistor is respectively connected to the third end of the controller and the first end of the twenty-third resistor, and the second end of the twenty-third resistor is grounded.

In a second aspect, an embodiment of the present disclosure provides an electronic device, the electronic device including the low-side driving circuit described in any one of the first aspect.

Optionally, in some embodiments of the present disclosure, the electronic device further includes a high-side drive circuit and a controller;

The first terminal, the second terminal and the third terminal of the controller are respectively connected to the low-side driving circuit, and the fourth terminal, the fifth terminal and the sixth terminal of the controller are respectively connected to the high-side driving circuit.

In a third aspect, an embodiment of the present disclosure provides a vehicle, the vehicle includes the electronic device described in any one of the second aspect.

It can be seen from the above technical solutions that the embodiments of the present disclosure have the following advantages:

In the low-side driving circuit provided by the embodiments of the present disclosure and the electronic equipment and vehicle thereof, the sampling module of the low-side driving circuit can convert the output current of the load into a first voltage signal, and output the first voltage signal to the current detection module, and then the current detection module can convert the first voltage signal, and output the converted second voltage signal to the controller, so that the controller can output a pulse width modulation signal to the current control module according to the second voltage signal, and then the current control module can control the on-off duration of the switch module according to the pulse width modulation signal output by the controller, so as to adjust the output current of the load. Therefore, the embodiment of the present disclosure can replace the functional chip by using the four components of the low-side drive circuit, namely the switch module, the sampling module, the current detection module and the current control module, to achieve the same function as the functional chip, and greatly reduce the manufacturing cost.

Description of drawings

Other characteristics, objects and advantages of the present disclosure will become more apparent by reading the detailed description of non-limiting embodiments made with reference to the following drawings:

FIG. 1 is an application block diagram of a low-side driving circuit provided by an embodiment of the present disclosure;

FIG. 2 is a structural block diagram of a low-side driving circuit provided by an embodiment of the present disclosure;

FIG. 3 is a structural block diagram of another low-side driving circuit provided by an embodiment of the present disclosure;

FIG. 4 is a structural block diagram of another low-side driving circuit provided by an embodiment of the present disclosure;

FIG. 5 is a structural block diagram of another low-side driving circuit provided by an embodiment of the present disclosure;

FIG. 6 is a structural block diagram of a low-side driving circuit provided by another embodiment of the present disclosure;

FIG. 7 is a schematic structural diagram of a low-side driving circuit provided by an embodiment of the present disclosure;

FIG. 8 is a schematic structural diagram of another low-side driving circuit provided by an embodiment of the present disclosure;

FIG. 9 is a schematic diagram of a time delay of a low-side driving circuit provided by an embodiment of the present disclosure;

FIG. 10 is a schematic diagram of current flow of a low-side driving circuit provided by an embodiment of the present disclosure;

FIG. 11 is a structural block diagram of an electronic device provided by an embodiment of the present disclosure;

FIG. 12 is a structural block diagram of another electronic device provided by an embodiment of the present disclosure;

FIG. 13 is a schematic structural diagram of a high-side driving circuit provided by an embodiment of the present disclosure;

Fig. 14 is a structural block diagram of a vehicle provided by an embodiment of the present disclosure.

Detailed ways

In order to enable those skilled in the art to better understand the present disclosure, the following will clearly and completely describe the technical solutions in the embodiments of the present disclosure in conjunction with the drawings in the embodiments of the present disclosure. Obviously, the described embodiments are only some of the embodiments of the present disclosure, not all of them. Based on the embodiments in the present disclosure, all other embodiments obtained by persons of ordinary skill in the art without creative efforts fall within the protection scope of the present disclosure.

The terms "first", "second", "third", "fourth", etc. (if any) in the description and claims of the present disclosure and the above drawings are used to distinguish similar objects and not necessarily to describe a specific order or sequence. It is to be understood that the data so used are interchangeable under appropriate circumstances such that the described embodiments of the disclosure can be practiced in sequences other than those illustrated or described herein.

Furthermore, the terms "comprising" and "having", as well as any variations thereof, are intended to cover non-exclusive inclusion, for example, a process, method, system, product or device comprising a series of steps or modules is not necessarily limited to those steps or modules explicitly listed, but may include other steps or modules not expressly listed or inherent to the process, method, product or device.

In order to facilitate understanding, it is now described in conjunction with the application block diagram shown in FIG. 1 . For example, the low-side driving circuit provided by the embodiments of the present disclosure may be applied in a driving circuit of a vehicle load. Exemplarily, the current of the power supply reaches the load through the high-side driving circuit, and then returns to the power supply through the low-side driving circuit of the embodiment of the present disclosure to form a loop. It should be noted that in Figure 1, "——" indicates the connection line of the power supply terminal, "—·—" indicates the connection line of the ground terminal, and "—" indicates the signal interaction line between the controller and the high-side drive circuit or between the controller and the low-side drive circuit. In actual use, for example, the controller can be a microcontroller (Microcontroller Unit, MCU). The microcontroller sends a control signal to the low-side drive circuit, and then the low-side drive circuit converts the output current of the load into a voltage signal and then feeds it back to the microcontroller, so that the microcontroller can adjust the pulse width modulation signal output to the low-side drive circuit according to the voltage signal to affect the output current of the load. Fault identification is performed according to the voltage signal, such as the output terminal is open, shorted to ground, or shorted to the power supply. The abnormal state of the circuit is handled to ensure safety.

Please refer to FIG. 2 , which is a structural block diagram of a low-side driving circuit provided by an embodiment of the present disclosure. The low-side driving circuit 100 includes a switch module 101 , a sampling module 102 , a current detection module 103 and a current control module 104 . Wherein, the first end of the switch module 101 is connected to the load, the second end of the switch module 101 is respectively connected to the first end of the sampling module 102 and the first end of the current detection module 103, the second end of the sampling module 102 is grounded, the second end of the current detection module 103 is connected to the first end of the controller, the first end of the current control module 104 is connected to the second end of the controller, and the second end of the current control module 104 is connected to the third end of the switch module 101. It should be noted that if there is no mark below, it means that the ground terminal can be the negative pole of the power supply, for example, the second terminal of the sampling module 102 is connected to the negative pole of the power supply.

Exemplarily, in the embodiment of the present disclosure, the low-side drive circuit 100 first converts the output current of the load into a first voltage signal through the sampling module 102 and then outputs it to the current detection module 103, and then through the current detection module 103 converts the first voltage signal into a second voltage signal and then outputs it to the controller to instruct the controller to output a pulse width modulation (Pulse Width Modulation, PWM) signal to the current control module 104 according to the second voltage signal, and then through the current control module 104 to control the switch according to the pulse width modulation signal output by the controller The on-off time of the module 101 is used to adjust the output current of the load. Therefore, the embodiment of the present disclosure can replace the function chip by using the four components of the switch module 101, the sampling module 102, the current detection module 103 and the current control module 104 in the low-side driving circuit 100, and achieve the same function as the function chip, greatly reducing the manufacturing cost.

Optionally, in some embodiments of the present disclosure, the switch module 101 may include a switch tube, wherein the first end of the switch tube is connected to the load, the second end of the switch tube is respectively connected to the first end of the sampling module 102 and the first end of the current detection module 103, and the third end of the switch tube is connected to the second end of the current control module 104. For example, the switch tube may include but not limited to a triode or a field effect tube. Taking the N-channel FET as an example, the first end of the switch is the drain d of the N-channel FET, the second end of the switch is the source s of the N-channel FET, and the third end of the switch is the gate g of the N-channel FET.

Optionally, as shown in FIG. 3 , in some embodiments of the present disclosure, the current detection module 103 may include an amplifying unit 1031 configured to convert the first voltage signal to obtain a second voltage signal and then output it to the controller. Wherein, the first end of the amplifying unit 1031 is respectively connected with the second end of the switch module 101 and the first end of the sampling module 102, the second end of the amplifying unit 1031 is connected with the first end of the controller, and the third end of the amplifying unit 1031 is connected with the second end of the sampling module 102.

Optionally, as shown in FIG. 4 , in some embodiments of the present disclosure, the current detection module 103 may further include a diagnostic unit 1032 configured to output a voltage signal, so that the controller can identify the operating state of the circuit according to the voltage signal. For example, the circuit operation state may include, but not limited to, any one of normal connection between the low-side driving circuit 100 and the load, an open circuit between the low-side driving circuit 100 and the load, and a short circuit between the low-side driving circuit 100 and the load. In the case of an open circuit or a short circuit, the current control module 104 controls the switch module 101 to switch to the disconnected state, and reconnects the switch module 101.

Optionally, as shown in FIG. 5 , in some embodiments of the present disclosure, the current control module 104 may include a control unit 1041 and a start unit 1042, the control unit 1041 is configured to receive a pulse width modulation signal output by the controller, and the start unit 1042 is configured to switch on and off according to the pulse width modulation signal, so as to control the on-off duration of the switch module 101. Wherein, the first terminal of the control unit 1041 is connected to the second terminal of the controller, the second terminal of the control unit 1041 is connected to the first terminal of the starting unit 1042 , and the second terminal of the starting unit 1042 is connected to the third terminal of the switch module 101 .

Optionally, as shown in FIG. 6 , in some embodiments of the present disclosure, the low-side drive circuit 100 may further include an overcurrent protection module 105 configured to, when receiving the first voltage signal output by the sampling module 102 greater than a preset voltage threshold, indicate that there is an abnormal condition in the circuit. At this time, the first voltage signal needs to be converted into a third voltage signal, so that the switch module 101 is continuously in the off state, ensuring device safety. Wherein, the first end of the overcurrent protection module 105 is connected to the first end of the sampling module 102, the second end of the overcurrent protection module 105 is connected to the second end of the sampling module 102, and the third end of the overcurrent protection module 105 is connected to the third end of the switch module 101.

Exemplarily, the overcurrent protection module 105 in some embodiments of the present disclosure may include a first level conversion unit, a second level conversion unit, and a third level conversion unit. The first level conversion unit is configured to convert the first voltage signal into a fourth voltage signal. The second level conversion unit is configured to convert the fourth voltage signal into a fifth voltage signal and then output to the first level conversion unit and the third level conversion unit. A fourth voltage signal. Wherein, the first end of the sampling module 102 is connected to the first level conversion unit, the first level conversion unit is connected to the second level conversion unit, the second level conversion unit is connected to the third level conversion unit, and the third level conversion unit is connected to the third end of the switch module 101 .

Optionally, in some embodiments of the present disclosure, the overcurrent protection module 105 may further include a voltage limiting unit configured to detect a change of the first voltage signal and perform voltage division to protect ports of the controller. Wherein, the first terminal of the voltage limiting unit is connected to the second terminal of the second level conversion unit, the second terminal of the voltage limiting unit is connected to the third terminal of the controller, the third terminal of the voltage limiting unit is grounded, the fourth terminal of the voltage limiting unit is connected to the output terminal of the power management chip, and the fifth terminal of the voltage limiting unit is grounded.

For example, please refer to FIG. 7 , the specific circuit structure of each component module or unit in the low-side driving circuit 100 will be described in detail below.

For example, the switch transistor in the switch module 101 is a field effect transistor Q00, and the field effect transistor Q00 may include but not limited to an N-channel MOS transistor, and its current level is selected according to actual load requirements. Specifically, the drain d of the field effect transistor Q00 (corresponding to the first end of the switch module 101) is connected to the load, the source s of the field effect transistor Q00 (corresponding to the second end of the switch module 101) is respectively connected to the first end of the sampling module 102 and the first end of the current detection module 103, and the gate g of the field effect transistor Q00 (corresponding to the third end of the switch module 101) is connected to the second end of the current control module 104.

Optionally, in some embodiments of the present disclosure, the low-side driving circuit 100 may further include a first diode D1, and the first diode D1 may be used to provide a freewheeling circuit for the load when the field effect transistor Q00 is in an off state. Wherein, the anode of the first diode D1 is connected to the drain d of the field effect transistor Q00 (corresponding to the first end of the switching transistor), and the cathode of the first diode D1 is connected to the output terminal of the high-side driving circuit.

Optionally, as shown in FIG. 8 , in some embodiments of the present disclosure, in addition to the field effect transistor Q00, the switch module 101 may also include a first transistor Q1, a second transistor Q2, a first resistor R1, and a second resistor R2. The first transistor Q1 may include but not limited to an NPN transistor, and the second transistor Q2 may include but not limited to a PNP transistor. Wherein, the second terminal of the current control module 104 is respectively connected to the base b of the first transistor Q1 and the base b of the second transistor Q2, the collector c of the second transistor Q2 is grounded, the emitter e of the second transistor Q2 is connected to the grid g of the field effect transistor Q00 (corresponding to the third terminal of the switching transistor), the emitter e of the first transistor Q1 is connected to the first terminal of the first resistor R1, and the second terminal of the first resistor R1 is connected to the gate g of the field effect transistor Q00 (corresponding to the third terminal of the switching transistor). The collector c of the first triode Q1 is connected to the positive pole of the power supply, the first end of the second resistor R2 is connected to the gate g of the field effect transistor Q00 (corresponding to the third end of the switching transistor), and the second end of the second resistor R2 is grounded.

For another example, the sampling module 102 may include a resistor R0, the first end of the resistor R0 is connected to the second end of the switch module 101 (corresponding to the source s of the field effect transistor Q00), and the second end of the resistor R0 is grounded.

For another example, the amplifying unit 1031 in the current detection module 103 may include an operational amplifier U1, a third resistor R3, a fourth resistor R4, and a fifth resistor R5. Wherein, the first end of the third resistor R3 (corresponding to the first end of the current detection module 103) is respectively connected to the second end of the switch module 101 (corresponding to the source s of the field effect transistor Q00) and the first end of the sampling module 102; end is connected to the first end of the fifth resistor R5, and the second end of the fifth resistor R5 (corresponding to the second end of the current detection module 103) is connected to the first end of the controller. For example, the first end of the controller is an analog input/output interface.

Optionally, in some embodiments of the present disclosure, the amplifying unit 1031 may further include a sixth resistor R6, a seventh resistor R7, a first capacitor C1, a second capacitor C2, and a third capacitor C3. Wherein, the first terminal of the sixth resistor R6 is connected to the second terminal of the third resistor R3, the second terminal of the sixth resistor R6 is grounded, the first terminal of the first capacitor C1 is connected to the second terminal of the third resistor R3, the second terminal of the first capacitor C1 is grounded, the first terminal of the seventh resistor R7 is connected to the negative input terminal of the operational amplifier U1, the second terminal of the seventh resistor R7 is connected to the output terminal of the operational amplifier U1, the first terminal of the second capacitor C2 is connected to the first terminal of the seventh resistor R7, the second terminal of the second capacitor C2 is connected to the second terminal of the seventh resistor R7, and the second terminal of the third capacitor C3 The first terminal is connected to the second terminal of the fifth resistor R5, and the second terminal of the third capacitor C3 is grounded.

It should be noted that, assuming that the voltage of the resistor R0 is U _R0 , if the value of the resistor is R _R3 =R _R4 and R _R6 =R _R7 , then the amplification factor β of the operational amplifier U1 is the ratio of R _R7 to _RR4 , that is, β=R _R7 /R _R4 . Wherein, U _R0 is the product of the current through the resistor R0 and the resistance value R _R0 , and the current through the resistor R0 is approximately equal to the current flowing through the field effect transistor Q00 and approximately equal to the output current of the load.

For another example, the diagnostic unit 1032 in the current detection module 103 may include an eighth resistor R8, the first end of the eighth resistor R8 is connected to the output end of the high-side drive circuit, and the second end of the eighth resistor R8 is connected to the first end of the switch module 101 (corresponding to the drain d of the field effect transistor Q00).

Optionally, in some embodiments of the present disclosure, the amplifying unit 1031 may further include a fourth capacitor C4, where the fourth capacitor C4 is used to protect a circuit port. Wherein, the first end of the fourth capacitor C4 is connected to the second end of the eighth resistor R8, and the second end of the fourth capacitor C4 is grounded.

As another example, the control unit 1041 in the current control module 104 may include a band-stop transistor Q01 and a ninth resistor R9, the starting unit 1042 may include a tenth resistor R10, a third transistor Q3, an eleventh resistor R11, and a twelfth resistor R12, and the third transistor Q3 may include but not limited to a PNP transistor. Wherein, the base b of the band-stop transistor Q01 (corresponding to the first end of the current control module 104) is connected to the second end of the controller, the emitter e of the band-stop transistor Q01 is grounded, the collector c of the band-stop transistor Q01 is connected to the first end of the ninth resistor R9, the second end of the ninth resistor R9 is respectively connected to the first end of the tenth resistor R10 and the base b of the third transistor Q3, the emitter e of the third transistor Q3 and the second end of the tenth resistor R10 are both connected to the positive pole of the power supply Connection, for example, the voltage of the power supply is 12V, the collector c of the third transistor Q3 is connected to the first end of the eleventh resistor R11, the second end of the eleventh resistor R11 (corresponding to the second end of the current control module 104) is respectively connected to the third end of the switch module 101 (corresponding to the gate g of the field effect transistor Q00) and the first end of the twelfth resistor R12, and the second end of the twelfth resistor R12 is grounded.

Optionally, as shown in FIG. 8 , in some embodiments of the present disclosure, the control unit 1041 may include a thirteenth resistor R13, a fourteenth resistor R14, a fifteenth resistor R15, and a fourth transistor Q4. The fourth transistor Q4 may include but not limited to an NPN transistor. The startup unit 1042 may include a tenth resistor R10, a third transistor Q3, an eleventh resistor R11, and a twelfth resistor R12. The third transistor Q3 may include but not limited to a PNP transistor. Wherein, the first end of the thirteenth resistor R13 (corresponding to the first end of the current control module 104) is connected to the second end of the controller, the second end of the thirteenth resistor R13 is respectively connected to the first end of the fourteenth resistor R14 and the base b of the fourth transistor Q4, the second end of the fourteenth resistor R14 is grounded, the emitter e of the fourth transistor Q4 is connected to the first end of the fifteenth resistor R15, the second end of the fifteenth resistor R15 is grounded, and the collector c of the fourth transistor Q4 is respectively connected to the tenth resistor R10. The first terminal of the third transistor Q3 is connected to the base b of the third transistor Q3, the emitter e of the third transistor Q3 and the second terminal of the tenth resistor R10 are both connected to the positive pole of the power supply, the collector c of the third transistor Q3 is connected to the first terminal of the eleventh resistor R11, and the second terminal of the eleventh resistor R11 (corresponding to the second terminal of the current control module 104) is respectively connected to the third terminal of the switch module 101 (corresponding to the gate g of the field effect transistor Q00) and the first terminal of the twelfth resistor R12, and the twelfth resistor R1 The second terminal of 2 is grounded.

It should be noted that, in addition to receiving the pulse width modulation signal output by the controller, the current control module 104 can also receive the level signal output by the controller. When the pulse width modulation signal rate increases or the response time of the switch module 101 is required, the low-side drive circuit in FIG. 8 can reduce the turn-off delay time of the switch module 101 compared with the low-side drive circuit in FIG. The reason is that the turn-off speed of the band-stop transistor Q01 is slow when it works in the saturation region, and it is replaced by the fourth transistor Q4, and the common-emitter amplifier circuit is obtained after adding the thirteenth resistor R13, the fourteenth resistor R14 and the fifteenth resistor R15 accordingly, so that the fourth transistor Q4 can work in the amplification region, so that it can be turned off more quickly. Pulling the buffer stage can increase the charging and discharging speed of the gate capacitance of the field effect transistor Q00, thereby accelerating the switching speed of the field effect transistor Q00.

Optionally, in some embodiments of the present disclosure, the control unit 1041 may further include a second diode D2 and a third diode D3 to protect the protection circuit port. The start-up unit 1042 may also include a fourth diode D4, which may include but not limited to a clamping diode. The benefit of such an arrangement is that it can protect the safety of the field effect transistor Q00 and avoid damage. Wherein, the anode of the second diode D2 is connected to the second end of the controller, the cathode of the second diode D2 is connected to the output end of the power management chip, the anode of the third diode D3 is connected to the ground, the cathode of the third diode D3 is connected to the anode of the second diode D2, the anode of the fourth diode D4 is connected to the second end of the twelfth resistor R12, and the cathode of the fourth diode D4 is connected to the first end of the twelfth resistor R12.

For another example, the first level conversion unit in the overcurrent protection module 105 may include a sixteenth resistor R16, a seventeenth resistor R17, an eighteenth resistor R18, and a fifth transistor Q5. The fifth transistor Q5 may include but not limited to an NPN transistor. The second level conversion unit may include a sixth transistor Q6 and a nineteenth resistor R19. The sixth transistor Q6 may include but not limited to a PNP transistor. The third level conversion unit may include a twentieth resistor R20 and a seventh transistor Q7. Tube Q7 may include, but is not limited to, an NPN tube. In actual use, the preset voltage threshold may be the be electrode voltage V _be _Q7 of the seventh transistor Q7. Wherein, the first end of the sixteenth resistor R16 (corresponding to the first end of the overcurrent protection module 105) is connected to the first end of the sampling module 102, the second end of the sixteenth resistor R16 is respectively connected to the base b of the fifth transistor Q5 and the first end of the eighteenth resistor R18, the emitter e of the fifth transistor Q5 (corresponding to the second end of the overcurrent protection module 105) is connected to the second end of the sampling module 102, the collector c of the fifth transistor Q5 is respectively connected to the first end of the seventeenth resistor R17 and the first end of the eighteenth resistor R18. The first end of the nineteenth resistor R19 is connected, the second end of the seventeenth resistor R17 is connected to the positive pole of the power supply, the second end of the nineteenth resistor R19 is connected to the base b of the sixth transistor Q6, the emitter e of the sixth transistor Q6 is connected to the third end of the current control module 104, the collector c of the sixth transistor Q6 is connected to the second end of the eighteenth resistor R18 and the first end of the twentieth resistor R20 respectively, and the second end of the twentieth resistor R20 is connected to the base b of the seventh transistor Q7, the seventh three The emitter e of the transistor Q7 is connected to the second terminal of the sampling module 102, and the collector c of the seventh transistor Q7 (corresponding to the third terminal of the overcurrent protection module 105) is connected to the third terminal of the switch module 101 (corresponding to the gate g of the field effect transistor Q00).

Optionally, in some embodiments of the present disclosure, the second level conversion unit may further include a fifth diode D5, which has the advantage of protecting the sixth transistor Q6 from reverse breakdown. Wherein, the anode of the fifth diode D5 is connected to the third terminal of the current control module 104, and the cathode of the fifth diode D5 is connected to the emitter e of the sixth transistor Q6.

For another example, the voltage limiting unit in the overcurrent protection module 105 may include a twenty-first resistor R21, a twenty-second resistor R22, a twenty-third resistor R23, a sixth diode D6 and a seventh diode D7. Wherein, the first terminal of the twenty-first resistor R21 is connected to the second terminal of the second level conversion unit, the second terminal of the twenty-first resistor R21 is respectively connected to the first terminal of the twenty-second resistor R22 and the positive pole of the sixth diode D6, the negative pole of the sixth diode D6 is connected to the output terminal of the power management chip, for example, the voltage at the output terminal of the power management chip is 5V, the negative pole of the seventh diode D7 is connected to the positive pole of the sixth diode D6, the positive pole of the seventh diode D7 is grounded, and the second terminal of the twenty-second resistor R22 is respectively connected to the third terminal and the second terminal of the controller. The first end of the thirteenth resistor R23 is connected to the ground, and the second end of the twenty-third resistor R23 is grounded. For example, the third terminal of the controller is a digital input/output interface, and the high-low state of the first terminal of the twenty-third resistor R23 is related to the state of the control signal, that is, the high-low state of the first terminal of the twenty-third resistor R23 is read when the control signal is at a high level.

The working principle of the low-side driving circuit 100 provided by the embodiment of the present disclosure will be described below with reference to FIG. 7 and FIG. 10 . In the first working stage, the field effect transistor Q00, the band-stop transistor Q01, the third transistor Q3, the fifth transistor Q5, the sixth transistor Q6 and the seventh transistor Q7 are all in the off state, that is, the control signal output by the second terminal of the controller is at a low level, at this time the low-side drive circuit 100 does not work, and the current flows as shown in Figure 10 ①, that is, load → first diode D1 → eighth resistor R8 → load.

In the second working stage, when the control signal output by the second terminal of the controller is at a high level, the band-stop transistor Q01 is turned on, so that the third transistor Q3 is turned on, the eleventh resistor R11 and the twelfth resistor R12 divide the voltage, and then the field effect transistor Q00 is turned on to provide a current loop to the load. At this time, the current flow direction is as shown in Figure 10 ②, that is, load → field effect transistor Q00 → resistor R0.

In the third working stage, when the current at the resistor R0 is too large, the overcurrent protection is implemented. At this time, the voltage between the base b and the emitter e of the fifth transistor Q5 and the seventh transistor Q7 will increase, so that the fifth transistor Q5 and the seventh transistor Q7 are turned on, and the current flow direction is as shown in Figure 10. 00→sixteenth resistor R16→seventh transistor Q7, at this time, due to the influence of the collector c of the seventh transistor Q7 pulling down the voltage, the field effect transistor Q00 can be turned off in time. Afterwards, since there is no current at the resistor R0, the base voltage of the fifth transistor Q5 becomes the voltage of the node between the eighteenth resistor R18 and the twentieth resistor R20, thereby maintaining the fifth transistor Q5 in the conduction state, and further maintaining the sixth transistor Q6 and the seventh transistor Q7 in the conduction state, so that the field effect transistor Q00 is continuously in the off state, thereby protecting the circuit safety.

In addition, it should be noted that if the voltage at the first terminal of the controller is β*V _be_Q7, it indicates that the second terminal of the eighth resistor R8 has an abnormal fault of short circuit to the power supply; if the voltage of the first terminal of the controller is 0, it indicates that the second terminal of the eighth resistor R8 has an abnormal fault of short circuit to the ground; _LThe divided voltage corresponding to the resistor R0 after being connected in parallel and in series with the resistor R0 indicates that the second end of the eighth resistor R8 is normally connected to the load.

As another aspect, an embodiment of the present disclosure also provides an electronic device. As shown in FIG. 11 , the electronic device 200 may include, but is not limited to, the low-side driving circuit 100 in the embodiments corresponding to FIG. 2 to FIG. 10 .

Optionally, as shown in FIG. 12 , the electronic device 200 in some embodiments of the present disclosure may further include a high-side driving circuit 300 and a controller 400. Wherein, the first terminal, the second terminal and the third terminal of the controller 400 are respectively connected to the low-side driving circuit 100 , and the fourth terminal, the fifth terminal and the sixth terminal of the controller 400 are respectively connected to the high-side driving circuit 300 .

Exemplarily, as shown in FIG. 13 , which is a specific structural diagram of a high-side driving circuit provided by an embodiment of the present disclosure, the high-side driving circuit 300 may include a first module 3001, a second module 3002, and a third module 3003, wherein the first module 3001 includes a transistor q1, a transistor q2, a transistor q3, a resistor r1, a resistor r2, a resistor r3, a resistor r4, a resistor r5, a resistor r6, a resistor r7, a resistor r8, a diode d1, a diode d2 and diode d3; the second module 3002 includes resistor r0, resistor r9, resistor r10, resistor r11, resistor r12, diode d4, capacitor c1 and capacitor c2; and, the third module 3003 includes transistor q4, switch tube q5, resistor r13, resistor r14 and diode d5.

It should be noted that the fourth end of the controller 400 is connected to the first end of the resistor r8 in the high-side drive circuit 300, namely “(1)” shown in FIG. In addition, the port "(4)" shown in Figure 13 is connected to a load, and "(5) represents a power supply.

As yet another aspect, an embodiment of the present disclosure also provides a vehicle. As shown in FIG. 14 , the vehicle 500 may include, but not limited to, the electronic device 200 in the embodiments corresponding to FIG. 11 to FIG. 13 .

Embodiments of the present disclosure provide a low-side driving circuit and an electronic device and a vehicle having the same. The sampling module of the low-side driving circuit can convert the output current of the load into a first voltage signal, and output the first voltage signal to the current detection module, and then the current detection module can convert the first voltage signal, and output the converted second voltage signal to the controller, so that the controller can output a pulse width modulation signal to the current control module according to the second voltage signal, and then the current control module can control the on-off duration of the switch module according to the pulse width modulation signal output by the controller, so as to adjust the output current of the load. Therefore, the embodiment of the present disclosure can replace the functional chip by using the four components of the low-side drive circuit, namely the switch module, the sampling module, the current detection module and the current control module, to achieve the same function as the functional chip, and greatly reduce the manufacturing cost.

The technical features of the above embodiments can be combined arbitrarily. To make the description concise, all possible combinations of the technical features in the above embodiments are not described. However, as long as there is no contradiction in the combination of these technical features, they should be considered as within the scope of this specification.

The above examples only express several implementations of the present disclosure, and the descriptions thereof are relatively specific and detailed, but should not be construed as limiting the scope of the disclosed patents. It should be noted that those skilled in the art can make several modifications and improvements without departing from the concept of the present disclosure, and these all belong to the protection scope of the present disclosure.

Claims (23)

1. A low-side drive circuit, characterized in that the circuit includes a switch module, a sampling module, a current detection module and a current control module;

   The first end of the switch module is connected to the load, the second end of the switch module is respectively connected to the first end of the sampling module and the first end of the current detection module, the second end of the sampling module is grounded, the second end of the current detection module is connected to the first end of the controller, the first end of the current control module is connected to the second end of the controller, and the second end of the current control module is connected to the third end of the switch module;

   The sampling module is configured to convert the output current of the load into a first voltage signal and output it to the current detection module;

   The current detection module is configured to convert the first voltage signal into a second voltage signal and output it to the controller, so as to instruct the controller to output a pulse width modulation signal to the current control module according to the second voltage signal;

   The current control module is configured to control the on-off duration of the switch module according to the pulse width modulation signal output by the controller, so as to adjust the output current of the load.
2. The low-side drive circuit according to claim 1, wherein the switch module comprises a switch tube;

   The first end of the switch tube is connected to the load, the second end of the switch tube is respectively connected to the first end of the sampling module and the first end of the current detection module, and the third end of the switch tube is connected to the second end of the current control module.
3. The low-side driving circuit according to claim 2, further comprising a first diode, the anode of the first diode is connected to the first end of the switching tube, and the cathode of the first diode is connected to the output end of the high-side driving circuit.
4. The low-side drive circuit according to claim 2 or 3, wherein the switch module further comprises a first triode, a second triode, a first resistor and a second resistor;

   The second end of the current control module is respectively connected to the base of the first triode and the base of the second triode, the collector of the second triode is grounded, the emitter of the second triode is connected to the third end of the switch, the emitter of the first triode is connected to the first end of the first resistor, the second end of the first resistor is connected to the third end of the switch, the collector of the first triode is connected to the positive pole of the power supply, the first end of the second resistor is connected to the third end of the switch, and the second end of the second resistor is grounded.
5. The low-side drive circuit according to claim 1, wherein the current detection module includes an amplification unit;

   The first end of the amplifying unit is respectively connected to the second end of the switch module and the first end of the sampling module, the second end of the amplifying unit is connected to the first end of the controller, and the third end of the amplifying unit is connected to the second end of the sampling module;

   The amplifying unit is configured to convert the first voltage signal to obtain the second voltage signal and output it to the controller.
6. The low-side drive circuit according to claim 5, wherein the amplifying unit comprises an operational amplifier, a third resistor, a fourth resistor, and a fifth resistor;

   The first terminal of the third resistor is respectively connected to the second terminal of the switch module and the first terminal of the sampling module, the second terminal of the third resistor is connected to the positive input terminal of the operational amplifier, the first terminal of the fourth resistor is connected to the second terminal of the sampling module, the second terminal of the fourth resistor is respectively connected to the negative input terminal of the operational amplifier and the output terminal of the operational amplifier, the output terminal of the operational amplifier is connected to the first terminal of the fifth resistor, and the second terminal of the fifth resistor is connected to the first terminal of the controller.
7. The low-side drive circuit according to claim 6, wherein the amplifying unit further comprises a sixth resistor, a seventh resistor, a first capacitor, a second capacitor and a third capacitor;

   The first terminal of the sixth resistor is connected to the second terminal of the third resistor, the second terminal of the sixth resistor is grounded, the first terminal of the first capacitor is connected to the second terminal of the third resistor, the second terminal of the first capacitor is grounded, the first terminal of the seventh resistor is connected to the negative input terminal of the operational amplifier, the second terminal of the seventh resistor is connected to the output terminal of the operational amplifier, the first terminal of the second capacitor is connected to the first terminal of the seventh resistor, the second terminal of the second capacitor is connected to the second terminal of the seventh resistor, the first terminal of the third capacitor is connected to the second terminal of the fifth resistor, and the second terminal of the third capacitor grounded.
8. The low-side drive circuit according to claim 5, wherein the current detection module further comprises a diagnostic unit;

   The first terminal of the diagnostic unit is connected to the output terminal of the high-side drive circuit, and the second terminal of the diagnostic unit is connected to the first terminal of the switch module;

   The diagnosis unit is configured to output a voltage signal, so that the controller recognizes a circuit operation state according to the voltage signal.
9. The low-side drive circuit according to claim 8, wherein the circuit operation state includes any one of normal connection between the low-side drive circuit and the load, an open circuit between the low-side drive circuit and the load, and a short circuit between the low-side drive circuit and the load;

   Wherein, in the case of the open circuit or the short circuit, the current control module controls the switch module to switch to an off state, and reconnects the switch module.
10. The low-side drive circuit according to claim 8 or 9, wherein the diagnostic unit includes an eighth resistor, a first end of the eighth resistor is connected to the output end of the high-side drive circuit, and a second end of the eighth resistor is connected to the first end of the switch module.
11. The low-side drive circuit according to claim 1, wherein the current control module comprises a control unit and a startup unit;

    The first terminal of the control unit is connected to the second terminal of the controller, the second terminal of the control unit is connected to the first terminal of the starting unit, and the second terminal of the starting unit is connected to the third terminal of the switch module;

    The control unit is configured to receive the pulse width modulation signal output by the controller, and the starting unit is configured to switch on and off according to the pulse width modulation signal, so as to control the on-off duration of the switch module.
12. The low-side drive circuit according to claim 11, wherein the control unit includes a band-stop transistor and a ninth resistor, and the startup unit includes a tenth resistor, a third transistor, an eleventh resistor, and a twelfth resistor;

    The base of the band-stop transistor is connected to the second end of the controller, the emitter of the band-stop transistor is grounded, the collector of the band-stop transistor is connected to the first end of the ninth resistor, the second end of the ninth resistor is respectively connected to the first end of the tenth resistor and the base of the third transistor, the emitter of the third transistor and the second end of the tenth resistor are connected to the positive pole of the power supply, the collector of the third transistor is connected to the first end of the eleventh resistor, and the second end of the eleventh resistor is respectively connected to the switch module. The third end is connected to the first end of the twelfth resistor, and the second end of the twelfth resistor is grounded.
13. The low-side drive circuit according to claim 11 or 12, wherein the control unit includes a thirteenth resistor, a fourteenth resistor, a fifteenth resistor, and a fourth triode, and the startup unit includes a tenth resistor, a third triode, an eleventh resistor, and a twelfth resistor;

    The first end of the thirteenth resistor is connected to the second end of the controller, the second end of the thirteenth resistor is respectively connected to the first end of the fourteenth resistor and the base of the fourth transistor, the second end of the fourteenth resistor is grounded, the emitter of the fourth transistor is connected to the first end of the fifteenth resistor, the second end of the fifteenth resistor is grounded, the collector of the fourth transistor is respectively connected to the first end of the tenth resistor and the base of the third transistor, the emitter of the third transistor and the second end of the tenth resistor are connected to the power supply The collector of the third triode is connected to the first end of the eleventh resistor, the second end of the eleventh resistor is respectively connected to the third end of the switch module and the first end of the twelfth resistor, and the second end of the twelfth resistor is grounded.
14. The low-side drive circuit according to claim 12 or 13, wherein the control unit further includes a second diode and a third diode, and the startup unit further includes a fourth diode;

    The anode of the second diode is connected to the second terminal of the controller, the cathode of the second diode is connected to the output terminal of the power management chip, the anode of the third diode is connected to the ground, the cathode of the third diode is connected to the anode of the second diode, the anode of the fourth diode is connected to the second terminal of the twelfth resistor, and the cathode of the fourth diode is connected to the first terminal of the twelfth resistor.
15. The low-side drive circuit according to claim 1, wherein the circuit also includes an overcurrent protection module;

    The first end of the overcurrent protection module is connected to the first end of the sampling module, the second end of the overcurrent protection module is connected to the second end of the sampling module, and the third end of the overcurrent protection module is connected to the third end of the switch module;

    The overcurrent protection module is configured to convert the first voltage signal into a third voltage signal when receiving the first voltage signal output by the sampling module is greater than a preset voltage threshold, so that the switch module is continuously in an off state.
16. The low-side drive circuit according to claim 15, wherein the overcurrent protection module comprises a first level conversion unit, a second level conversion unit and a third level conversion unit;

    The first end of the sampling module is connected to the first level conversion unit, the first level conversion unit is connected to the second level conversion unit, the second level conversion unit is connected to the third level conversion unit, and the third level conversion unit is connected to the third end of the switch module;

    The first level conversion unit is configured to convert the first voltage signal into a fourth voltage signal, the second level conversion unit is configured to convert the fourth voltage signal into a fifth voltage signal and then output to the first level conversion unit and the third level conversion unit, the third level conversion unit is configured to convert the fifth voltage signal into the third voltage signal, and the first level conversion unit is further configured to convert the fifth voltage signal into the fourth voltage signal when the first voltage signal is not received.
17. The low-side drive circuit according to claim 16, wherein the first level shifting unit includes a sixteenth resistor, a seventeenth resistor, an eighteenth resistor, and a fifth triode, the second level shifting unit includes a sixth triode and a nineteenth resistor, and the third level shifting unit includes a twentieth resistor and a seventh triode;

    The first end of the sixteenth resistor is connected to the first end of the sampling module, the second end of the sixteenth resistor is connected to the base of the fifth triode and the first end of the eighteenth resistor respectively, the emitter of the fifth triode is connected to the second end of the sampling module, the collector of the fifth triode is respectively connected to the first end of the seventeenth resistor and the first end of the nineteenth resistor, the second end of the seventeenth resistor is connected to the positive pole of the power supply, the second end of the nineteenth resistor is connected to the base of the sixth triode, and the emitter of the sixth triode is connected to the first end of the sixteenth resistor. The pole is connected to the third end of the current control module, the collector of the sixth triode is connected to the second end of the eighteenth resistor and the first end of the twentieth resistor respectively, the second end of the twentieth resistor is connected to the base of the seventh triode, the emitter of the seventh triode is connected to the second end of the sampling module, and the collector of the seventh triode is connected to the third end of the switch module.
18. The low-side driving circuit according to claim 17, wherein the second level conversion unit further comprises a fifth diode, the anode of the fifth diode is connected to the third terminal of the current control module, and the cathode of the fifth diode is connected to the emitter of the sixth transistor.
19. The low-side drive circuit according to claim 16, wherein the overcurrent protection module further comprises a voltage limiting unit;

    The first terminal of the voltage limiting unit is connected to the second terminal of the second level conversion unit, the second terminal of the voltage limiting unit is connected to the third terminal of the controller, the third terminal of the voltage limiting unit is grounded, the fourth terminal of the voltage limiting unit is connected to the output terminal of the power management chip, and the fifth terminal of the voltage limiting unit is grounded;

    The voltage limiting unit is configured to detect the change of the first voltage signal, and divide the voltage to protect the port of the controller.
20. The low-side drive circuit according to claim 19, wherein the voltage limiting unit comprises a twenty-first resistor, a twenty-second resistor, a twenty-third resistor, a sixth diode, and a seventh diode;

    The first end of the twenty-first resistor is connected to the second end of the second level conversion unit, the second end of the twenty-first resistor is respectively connected to the first end of the twenty-second resistor and the anode of the sixth diode, the cathode of the sixth diode is connected to the output end of the power management chip, the cathode of the seventh diode is connected to the anode of the sixth diode, the anode of the seventh diode is grounded, the second end of the twenty-second resistor is respectively connected to the third end of the controller and the first end of the twenty-third resistor, and the second end of the twenty-third resistor is grounded.
21. An electronic device, characterized in that the electronic device comprises the low-side drive circuit according to any one of claims 1-20.
22. The electronic device according to claim 21, further comprising a high-side drive circuit and a controller;

    The first terminal, the second terminal and the third terminal of the controller are respectively connected to the low-side driving circuit, and the fourth terminal, the fifth terminal and the sixth terminal of the controller are respectively connected to the high-side driving circuit.
23. A vehicle, characterized in that the vehicle comprises the electronic device according to any one of claims 21 to 22.

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