A driving circuit and electronic equipment

Abstract

The disclosed embodiment provides a driving circuit and electronic device, including: MOS, a comparison module, a driving module, a high-power resistor, and a power supply; the comparison module is connected to the power supply; it is used to compare the power supply voltage with the preset voltage; it outputs a first output voltage to the driving module according to the comparison result; the driving module, the input end is connected to the comparison module, and the output end is connected to the MOS; it is used to output a second output voltage to drive the MOS to turn on when the first output voltage of the comparison module indicates that the voltage of the power supply is not less than the preset voltage; the MOS is connected to one end of the high-power resistor, and the other end of the high-power resistor is connected to the power supply, and after being turned on under the drive of the second output voltage, the power supply voltage is consumed by the high-power resistor to reduce the power supply voltage. This makes the power supply voltage more stable and prevents the abnormal increase of the power supply from causing damage to the device.

Description

Technical Field

[0001] The present disclosure relates to the field of motor technology, and in particular to a drive circuit and an electronic device. Background Art

[0002] A DC motor is a motor that relies on direct current to drive the moving body. The motor braking process actually converts the kinetic energy of the motor's own rotation into other forms of energy, thereby stopping the motor from rotating. There are many ways to convert energy. It can be converted into heat energy for dissipation or converted into electrical energy for storage in the battery. In the process of converting into other forms of energy for braking, the motor is equivalent to a generator, which will reverse the power supply. Improper handling will cause damage to the circuit components. Utility Model Content

[0003] The embodiments of the present disclosure provide a driving circuit and an electronic device to solve the problem of reverse charging of a power supply by a conventional DC motor brake causing damage to the device.

[0004] Based on the above problem, in a first aspect, a driving circuit is provided, comprising: a metal-oxide semiconductor field effect transistor MOS, a comparison module, a driving module, a high-power resistor, and a power supply;

[0005] The comparison module is connected to the power supply and is used to compare the power supply voltage with the preset voltage and output a first output voltage to the driving module according to the comparison result;

[0006] The driving module has an input end connected to the comparison module and an output end connected to the MOS; and is used to output a second output voltage to drive the MOS to turn on when the first output voltage of the comparison module indicates that the voltage of the power supply is not less than the preset voltage;

[0007] The MOS is connected to one end of the high-power resistor, and the other end of the high-power resistor is connected to the power supply. After being turned on by the second output voltage, the MOS consumes the power supply voltage through the high-power resistor to reduce the power supply voltage.

[0008] In an implementation manner of the first aspect, the driving module is further configured to turn off the MOS when the first output voltage of the comparison module indicates that the voltage of the power supply is less than the preset voltage.

[0009] In another embodiment of the first aspect, the driving circuit also includes: a reference power supply; the comparison module includes: a comparator U1, a first resistor R1, a second resistor R2, a third resistor R3 and a fourth resistor R4; the inverting input terminal of the comparator U1 is respectively connected to one end of the first resistor R1 and one end of the second resistor R2; the other end of the first resistor R1 is connected to the power supply; the other end of the second resistor R2 is grounded; the non-phase input terminal of the comparator U1 is respectively connected to one end of the third resistor R3 and one end of the fourth resistor R4; the other end of the third resistor R3 is connected to the reference power supply; the other end of the fourth resistor R4 is grounded; the output terminal of the comparator U1 is connected to the input terminal of the driving module.

[0010] In another embodiment of the first aspect, the comparator U1 is used to compare the first divided voltage of the first resistor R1 and the second resistor R2 with the second divided voltage of the third resistor R3 and the fourth resistor R4; when the power supply voltage is working normally, the first divided voltage is less than the second divided voltage, and the output first output voltage causes the driving module to drive the MOS to cut off; when the voltage increases and exceeds a preset value, the first divided voltage is not less than the second divided voltage, and the output first output voltage causes the driving module to drive the MOS to turn on; wherein the reference voltage of the reference power supply, the preset value, the first resistor R1, the second resistor R2, the third resistor R3 and the fourth resistor R4 are set according to the voltage value of the power supply when working normally, and the preset voltage tolerance value after the power supply voltage increases.

[0011] In another embodiment of the first aspect, the driving module includes: a first pull-up resistor R5 and a driving resistor R6; a first transistor Q1, a second transistor Q2, a third transistor Q3 and a second pull-up resistor R7; one end of the first pull-up resistor R5 is connected to one end of the driving resistor R6 and the output end of the comparator U1; the other end of the first pull-up resistor R5 is connected to the reference power supply; one end of the second pull-up resistor R7 is connected to the reference power supply; the other end is connected to the base of the first transistor Q1, the second transistor Q2, the third transistor Q3 and the second pull-up resistor R7; The collector of the first transistor Q1 is connected to the reference power supply, and the emitter is connected to the emitter of the third transistor Q3 and the gate of the MOS; the base of the second transistor Q2 is connected to the other end of the driving resistor R6 of the driving module, and the emitter is grounded; the collector of the third transistor Q3 is grounded; wherein the first transistor Q1 and the second transistor Q2 are NPN transistors, and the third transistor Q3 is a PNP transistor.

[0012] In another embodiment of the first aspect, the comparator U1 is used for, when the first divided voltage is not less than the second divided voltage, the first output voltage outputted from the output end of the comparator U1 is a low level; the driving module is used for pulling down the low level of the first output voltage through the first pull-up resistor R5; the base of the second transistor Q2 is cut off in response to the low level, so that the second pull-up resistor R7 pulls up the bases of the first transistor Q1 and the third transistor Q3, the first transistor Q1 is turned on in response to the high level, and the third transistor Q3 is turned off in response to the high level; the MOS is used for, in response to the first transistor Q1 being turned on, causing the high-power resistor to work and consume the voltage of the power supply, thereby reducing the power supply voltage.

[0013] In another embodiment of the first aspect, the comparator U1 is used to, when the first divided voltage is less than the second divided voltage, the first output voltage outputted from the output end of the comparator U1 is a high level; the driving module is used to pull up the high level of the first output voltage through the first pull-up resistor R5; the base of the second transistor Q2 is turned on in response to the high level, so that the second pull-up resistor R7 pulls down the bases of the first transistor Q1 and the third transistor Q3, the first transistor Q1 is turned off in response to the low level, and the third transistor Q3 is turned on in response to the low level; the MOS is used to make the branch where the high-power resistor is located not energized in response to the first transistor Q1 being turned off.

[0014] In another embodiment of the first aspect, the circuit also includes: a motor M; a gate of the MOS connected to the emitters of the first transistor Q1 and the third transistor Q3; a drain connected to one end of the high-power resistor, and a source grounded; the other end of the high-power resistor is connected to the power supply; one end of the motor M is connected to the power supply, and the other end is grounded; the MOS is used to drive the gate of the MOS to turn on in response to the first transistor Q1, so that the high-power resistor works to consume the voltage of the power supply, so that the power supply voltage drops; when the motor M is used for braking, the motor M reverse charges the power supply to increase the power supply voltage, and the first divided voltage is not less than the second divided voltage.

[0015] In another implementation of the first aspect, one end of the protection resistor R8 is connected to the power supply, and the other end of the protection resistor R8 is grounded; it is used to prevent the power supply from being short-circuited and protect the circuit when the MOS is turned off.

[0016] In a second aspect, the utility model provides an electronic device comprising: the MOS driving circuit described in the first aspect or any implementation of the first aspect.

[0017] The beneficial effects of the embodiments of the present disclosure include:

[0018] A driving circuit and electronic device provided by the embodiment of the present disclosure include: MOS, a comparison module, a driving module, a high-power resistor, and a power supply; the comparison module is connected to the power supply; used to compare the power supply voltage with the preset voltage; output a first output voltage to the driving module according to the comparison result; the driving module, the input end is connected to the comparison module, and the output end is connected to the MOS; when the first output voltage of the comparison module indicates that the voltage of the power supply is greater than the preset voltage, the second output voltage is output to drive the MOS to turn on; the MOS is connected to one end of the high-power resistor, and the other end of the high-power resistor is connected to the power supply, and after being turned on under the drive of the second output voltage, the power supply voltage is consumed by the high-power resistor to reduce the power supply voltage. A driving circuit provided by the present disclosure monitors the power supply voltage through the comparison module, and when the power supply voltage is detected to increase, the MOS is driven to turn on through the driving module, at this time, the branch where the high-power resistor is located is energized, and the power supply voltage is reduced by consuming the power supply voltage, so that the electronic device powered by the power supply is in the working process, even if the power supply is reversely charged, the driving circuit provided by the present disclosure can also reduce the power supply voltage, protect the electronic device, so that the power supply voltage is more stable during the working process of the electronic device, and the electronic device is not easy to be damaged. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 One of the schematic diagrams of a driving circuit structure provided in an embodiment of the present disclosure;

[0020] Figure 2 The present invention provides a second schematic diagram of a driving circuit structure according to an embodiment of the present invention. DETAILED DESCRIPTION

[0021] The embodiments of the present disclosure provide a driving circuit and an electronic device. The preferred embodiments of the present disclosure are described below in conjunction with the drawings of the specification. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present disclosure, and are not used to limit the present disclosure. In addition, the embodiments in the present application and the features in the embodiments can be combined with each other if there is no conflict.

[0022] The present disclosure provides a driving circuit. Figure 1 As shown, it includes: a metal-oxide semiconductor field effect transistor MOS101, a comparison module 102, a driving module 103, a high-power resistor 104, and a power supply 105;

[0023] The comparison module 102 is connected to the power supply 105 and is used to compare the power supply voltage with the preset voltage and output a first output voltage to the driving module 103 according to the comparison result;

[0024] The driving module 103 has an input end connected to the comparison module 102 and an output end connected to the MOS 101; when the first output voltage of the comparison module 102 indicates that the voltage of the power supply 105 is not less than a preset voltage, the driving module 103 outputs a second output voltage to drive the MOS 101 to conduct;

[0025] MOS 101 is connected to one end of a high-power resistor 104, and the other end of the high-power resistor 104 is connected to a power supply 105. After being turned on by the second output voltage, the high-power resistor 104 consumes the power supply voltage to reduce the power supply voltage.

[0026] In the disclosed embodiment, the power supply voltage is sampled by the comparator U1 in the comparison module 102, and the high and low levels are outputted after comparison with the preset voltage to control the driving module 103 to output high and low levels, thereby controlling the conduction and cutoff of the metal-oxide semiconductor field effect transistor (MOS, Metal-Oxide-Semiconductor Field-Effect Transistor) 101. The high-power resistor 104 is connected or suspended by the conduction and cutoff of MOS101. When the circuit is working normally, the high-power resistor 104 is suspended, and when the electronic device (for example: motor brake) reversely charges the power supply 105, the high-power resistor 104 is connected to consume excess energy, so that the voltage of the power supply 105 is stabilized within a reasonable range, and the device is prevented from being damaged by excessive voltage.

[0027] In another embodiment provided by the present disclosure, the driving module 103 is further configured to turn off the MOS 101 when the first output voltage of the comparison module 102 indicates that the voltage of the power source 105 is less than a preset voltage.

[0028] In this embodiment, when the first output voltage of the comparison module 102 indicates that the voltage of the power supply 105 is less than the preset voltage, the MOS 101 is turned off, that is, the high-power resistor 104 is suspended and does not need to consume the power supply voltage.

[0029] In another embodiment provided by the present disclosure, Figure 2 As shown, the driving circuit further includes: a reference power supply; the comparison module 102 includes: a comparator U1, a first resistor R1, a second resistor R2, a third resistor R3 and a fourth resistor R4;

[0030] The inverting input terminal of the comparator U1 is connected to one end of the first resistor R1 and one end of the second resistor R2 respectively; the other end of the first resistor R1 is connected to the power supply 105; the other end of the second resistor R2 is grounded;

[0031] The non-inverting input terminal of the comparator U1 is connected to one end of the third resistor R3 and one end of the fourth resistor R4 respectively; the other end of the third resistor R3 is connected to the reference power supply; the other end of the fourth resistor R4 is grounded;

[0032] The output terminal of the comparator U1 is connected to the input terminal of the driving module 103 .

[0033] In this embodiment, when the power supply voltage is compared with the preset voltage, in order to simplify the circuit design, the power supply voltage and the reference power supply can be divided respectively, and the divided voltages of the two can be compared. During implementation, the power supply 105 voltage can be divided by the first resistor R1 and the second resistor R2, and the voltage of the reference power supply can be divided by the third resistor R3 and the fourth resistor R4. Since the voltage of the reference power supply is fixed, the size of the divided voltage can be determined by adjusting the size of the third resistor R3 and the fourth resistor R4. The voltage of the power supply 105 during normal operation is different from the voltage generated after being reversely charged. The change range of the divided voltage can be determined after the power supply voltage is divided according to the normal voltage and the increased voltage that the circuit can withstand after reverse charging, and the size of the comparison threshold, that is, the size of the divided voltage of the reference power supply voltage, is determined, thereby determining the size of the third resistor R3 and the fourth resistor R4. In this way, comparing the power supply voltage with the preset voltage is equivalent to comparing the divided voltage of the power supply voltage with the divided voltage of the reference voltage.

[0034] In this way, the non-inverting input terminal of the comparator U1 inputs the divided voltage determined based on the reference power supply, and the inverting input terminal inputs the divided voltage determined based on the voltage of the power supply 105. The comparator U1 compares the divided voltages inputted at the two input terminals, and outputs a first output voltage indicating that the voltage of the power supply 105 is less than the preset voltage or indicating that the voltage of the power supply 105 is not less than the preset voltage. For example, a high level output indicates that the voltage of the power supply 105 is less than the preset voltage, and a low level output indicates that the voltage of the power supply 105 is not less than the preset voltage.

[0035] In another embodiment provided by the present disclosure, the comparator U1 is used to compare a first divided voltage of the first resistor R1 and the second resistor R2 with a second divided voltage of the third resistor R3 and the fourth resistor R4; when the power supply voltage is working normally, the first divided voltage is less than the second divided voltage, and the output first output voltage causes the driving module 103 to drive the MOS 101 to turn off; when the voltage rises and exceeds a preset value, the first divided voltage is not less than the second divided voltage, and the output first output voltage causes the driving module 103 to drive the MOS 101 to turn on;

[0036] Among them, the reference voltage of the reference power supply, the preset value, the first resistor R1, the second resistor R2, the third resistor R3 and the fourth resistor R4 are set according to the voltage value when the power supply 105 works normally and the preset voltage tolerance value after the power supply voltage is increased.

[0037] In this embodiment, it is assumed that the electronic device acted upon by the power supply voltage is a motor, the power supply voltage is 48V, the reference voltage is 12V, and the input voltage of the inverting input terminal of the comparator U1 is obtained by dividing the voltage of the first resistor R1 and the second resistor R2 to 1.8V. When the motor brakes, the power supply 105 is reversely charged. When the power supply voltage increases from 48V to a preset value, for example, when it increases to 53V, the voltage divided by the first resistor R1 and the second resistor R2 is greater than 2V, then the voltage divided by the reference voltage can be determined to be 2V. In this way, when the power supply 105 is working normally, the power supply voltage (1.8V) is less than 2V, and the comparator U1 outputs a high level, so that the MOS 101 is turned off; when the power supply 105 is reversely charged and the voltage rises to 53V, the voltage is divided (greater than 2V), and the comparator U1 outputs a low level, so that the drive circuit 103 drives the MOS 101 to turn on, thereby consuming the power supply voltage through the high-power resistor 104 to protect the circuit. Among them, the preset value can be set according to the tolerance of the actual circuit, which is not limited here.

[0038] In another embodiment provided by the present disclosure, Figure 2 As shown, the driving module 103 includes: a first pull-up resistor R5 and a driving resistor R6; a first transistor Q1, a second transistor Q2, a third transistor Q3 and a second pull-up resistor R7;

[0039] One end of the first pull-up resistor R5 is connected to one end of the driving resistor R6 and the output end of the comparator U1; the other end of the first pull-up resistor R5 is connected to the reference power supply;

[0040] One end of the second pull-up resistor R7 is connected to the reference power supply; the other end is connected to the base of the first transistor Q1, the collector of the second transistor Q2 and the base of the third transistor Q3;

[0041] The collector of the first transistor Q1 is connected to the reference power supply, and the emitter is connected to the emitter of the third transistor Q3 and the gate of MOS101;

[0042] The base of the second transistor Q2 is connected to the other end of the driving resistor R6 of the driving module, and the emitter is grounded;

[0043] The collector of the third transistor Q3 is grounded;

[0044] The first transistor Q1 and the second transistor Q2 are NPN transistors, and the third transistor Q3 is a PNP transistor.

[0045] In this embodiment, the first transistor Q1 and the second transistor Q2 can be NPN (Negative-Positive-Negative) type transistors, and the third transistor Q3 can be PNP (Positive-Negative-Positive) type transistor; when the first output voltage represents that the voltage of the power supply 105 is less than the preset voltage, the first transistor Q1 in the driving module 103 is turned on, the second transistor Q2 is turned on, and the third transistor Q3 is turned off, and the gate of MOS101 responds to a low level and is turned off; when the first output voltage represents that the voltage of the power supply 105 is not less than the preset voltage, the first transistor Q1 in the driving module 103 is turned on, the second transistor Q2 is turned off, and the third transistor Q3 is turned off, and the gate of MOS101 responds to a high level and is turned on.

[0046] In another embodiment provided by the present disclosure, the comparator U1 is used for, when the first divided voltage is not less than the second divided voltage, the first output voltage outputted from the output terminal of the comparator U1 is a low level;

[0047] The driving module 103 is used to pull down the low level of the first output voltage through the first pull-up resistor R5; the base of the second transistor Q2 is cut off in response to the low level, so that the second pull-up resistor R7 pulls up the bases of the first transistor Q1 and the third transistor Q3, the first transistor Q1 is turned on in response to the high level, and the third transistor Q3 is cut off in response to the high level;

[0048] MOS 101 is used for making the high-power resistor 104 work to consume the voltage of the power supply 105 in response to the first transistor Q1 being turned on.

[0049] In this embodiment, when the power supply voltage rises to a preset voltage or exceeds the preset voltage, the first divided voltage is not less than the second divided voltage, the first output voltage is a low level, the second output voltage is a high level, and MOS101 is turned on in response to the high level.

[0050] In another embodiment provided by the present disclosure, the comparator U1 is used for, when the first divided voltage is less than the second divided voltage, the first output voltage outputted from the output terminal of the comparator U1 is a high level;

[0051] The driving module 103 is used to pull up the high level of the first output voltage through the first pull-up resistor R5; the base of the second transistor Q2 is turned on in response to the high level, so that the second pull-up resistor R7 pulls down the bases of the first transistor Q1 and the third transistor Q3, the first transistor Q1 is turned off in response to the low level, and the third transistor Q3 is turned on in response to the low level;

[0052] MOS 101 is used for making the branch where the high-power resistor 104 is located not energized in response to the first transistor Q1 being turned off.

[0053] In this embodiment, when the power supply voltage remains stable or does not exceed the preset voltage after increasing, the first divided voltage is less than the second divided voltage, the first output voltage is high level, the second output voltage is low level, and MOS101 is cut off in response to the low level.

[0054] In another embodiment provided by the present disclosure, Figure 2 As shown, the above-mentioned driving circuit also includes: a motor M;

[0055] The gate of MOS 101 is connected to the emitters of the first transistor Q1 and the third transistor Q3; the drain is connected to one end of the high-power resistor 104, and the source is grounded;

[0056] The other end of the high-power resistor 104 is connected to the power supply 105; one end of the motor M is connected to the power supply 105, and the other end is grounded;

[0057] MOS101, used for responding to the first transistor Q1 driving the gate of MOS101 to be turned on, so that the high-power resistor 104 works to consume the voltage of the power supply 105, so that the voltage of the power supply 105 drops;

[0058] When the motor M is used for braking, the motor M reversely charges the power supply 105, so that the voltage of the power supply 105 increases, and the first divided voltage is not less than the second divided voltage.

[0059] In another embodiment provided by the present disclosure, one end of the protection resistor R8 is connected to the power supply 105, and the other end of the protection resistor R8 is grounded; it is used to prevent the power supply 105 from being short-circuited when the MOS 101 is turned off, thereby protecting the circuit.

[0060] The utility model also provides an electronic device, comprising the driving circuit provided by any of the above embodiments.

[0061] In one embodiment, when the motor M is working normally, the power supply voltage is 48V, the first resistor R1 is 51K, the second resistor R2 is 2K, and the first divided voltage input to the inverting input of the comparator is 1.81V; the reference voltage is 12V, the third resistor R3 is 10K, and the fourth resistor R4 is 2K, then the second divided voltage input to the non-inverting input of the comparator is fixed at 2V; at this time, the inverting input of the comparator is smaller than the non-inverting input, the first divided voltage is smaller than the second divided voltage, and the output The first output voltage is at a high level, and the first pull-up resistor R5 is implemented as 10K to pull up the high level of the first output voltage; the base of the second transistor Q2 is turned on in response to the high level, so that the second pull-up resistor R7 is implemented as 10K to pull down the bases of the first transistor Q1 and the third transistor Q3, the first transistor Q1 is turned off in response to the low level, and the third transistor Q3 is turned on in response to the low level; the MOS drives the gate of the MOS in response to the low level in response to the first transistor Q1, and the MOS is turned off.

[0062] When the motor M brakes, the motor M reversely charges the power supply, causing the power supply voltage 48V to increase, and the preset voltage is realized as 53V. When the power supply voltage increases to the preset voltage 53V or greater than 53V, the first divided voltage input to the inverting input of the comparator is realized as 2V; the second divided voltage input to the non-inverting input of the comparator is realized as a fixed 2V; at this time, the inverting input of the comparator is not less than the non-inverting input, the first divided voltage is not less than the second divided voltage, the output first output voltage is a low level, and the first pull-up resistor R5 is realized as 10K to pull down the low level of the first output voltage; the base of the second transistor Q2 is cut off in response to the low level, so that the second pull-up resistor R7 pulls up the bases of the first transistor Q1 and the third transistor Q3, the first transistor Q1 is turned on in response to the high level, and the third transistor Q3 is turned off in response to the high level; the MOS responds to the high level driven by the first transistor Q1 to drive the gate of the MOS, the MOS is turned on, and the high-power resistor is connected to the circuit to consume the power supply voltage to make the power supply voltage continue to drop until it returns to the normal state of 48V. The reference values ​​in this embodiment are only examples and do not limit the present application.

[0063] In this embodiment, if there is no protection resistor R8, the circuit will have a power short circuit, which will affect the circuit safety.

[0064] Those skilled in the art will appreciate that the accompanying drawings are merely schematic diagrams of a preferred embodiment, and the modules or processes in the accompanying drawings are not necessarily necessary for implementing the present invention.

[0065] The serial numbers of the above-mentioned embodiments of the present invention are only for description and do not represent the advantages or disadvantages of the embodiments.

[0066] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A driving circuit, characterized in that: include: Metal-oxide semiconductor field effect transistor MOS, comparison module, driving module, high-power resistor, and power supply; The comparison module is connected to the power supply; Used to compare the power supply voltage with a preset voltage; outputting a first output voltage to the driving module according to the comparison result; The driving module has an input end connected to the comparison module and an output end connected to the MOS; For outputting a second output voltage to drive the MOS to conduct when the first output voltage of the comparison module indicates that the voltage of the power supply is not less than the preset voltage; The MOS is connected to one end of the high-power resistor, and the other end of the high-power resistor is connected to the power supply, and is used to consume the power supply voltage through the high-power resistor after being turned on under the drive of the second output voltage, so that the power supply voltage decreases.

2. The circuit according to claim 1, characterized in that The driving module is further configured to turn off the MOS when the first output voltage of the comparison module indicates that the voltage of the power supply is less than the preset voltage.

3. The circuit according to claim 1 or 2, characterized in that The driving circuit further includes: a reference power supply; the comparison module includes: a comparator U1, a first resistor R1, a second resistor R2, a third resistor R3 and a fourth resistor R4; The inverting input terminal of the comparator U1 is connected to one end of the first resistor R1 and one end of the second resistor R2 respectively; the other end of the first resistor R1 is connected to the power supply; the other end of the second resistor R2 is grounded; The non-inverting input terminal of the comparator U1 is connected to one end of the third resistor R3 and one end of the fourth resistor R4 respectively; the other end of the third resistor R3 is connected to the reference power supply; the other end of the fourth resistor R4 is grounded; The output end of the comparator U1 is connected to the input end of the driving module.

4. The circuit according to claim 3, characterized in that The comparator U1 is used to compare a first divided voltage between the first resistor R1 and the second resistor R2 with a second divided voltage between the third resistor R3 and the fourth resistor R4; When the power supply voltage is working normally, the first divided voltage is smaller than the second divided voltage, and the output first output voltage causes the driving module to drive the MOS to be cut off; When the voltage increases and exceeds a preset value, the first divided voltage is not less than the second divided voltage, and the output first output voltage enables the driving module to drive the MOS to turn on; Among them, the reference voltage of the reference power supply, the preset value, the first resistor R1, the second resistor R2, the third resistor R3 and the fourth resistor R4 are set according to the voltage value when the power supply works normally and the preset voltage tolerance value after the power supply voltage is increased.

5. The circuit according to claim 4, characterized in that The driving module includes: a first pull-up resistor R5 and a driving resistor R6; a first transistor Q1, a second transistor Q2, a third transistor Q3 and a second pull-up resistor R7; One end of the first pull-up resistor R5 is connected to one end of the driving resistor R6 and the output end of the comparator U1; the other end of the first pull-up resistor R5 is connected to the reference power supply; One end of the second pull-up resistor R7 is connected to the reference power supply; the other end is connected to the base of the first transistor Q1, the collector of the second transistor Q2 and the base of the third transistor Q3; The collector of the first transistor Q1 is connected to the reference power supply, and the emitter is connected to the emitter of the third transistor Q3 and the gate of the MOS; The base of the second transistor Q2 is connected to the other end of the driving resistor R6 of the driving module, and the emitter is grounded; The collector of the third transistor Q3 is grounded; The first transistor Q1 and the second transistor Q2 are NPN transistors, and the third transistor Q3 is a PNP transistor.

6. The circuit according to claim 5, characterized in that The comparator U1 is configured to output the first output voltage at the output end of the comparator U1 at a low level when the first divided voltage is not less than the second divided voltage; The driving module is used to pull down the low level of the first output voltage through the first pull-up resistor R5; the base of the second transistor Q2 is turned off in response to the low level, so that the second pull-up resistor R7 pulls up the bases of the first transistor Q1 and the third transistor Q3, the first transistor Q1 is turned on in response to the high level, and the third transistor Q3 is turned off in response to the high level; The MOS is used for causing the high-power resistor to work and consume the voltage of the power supply in response to the first transistor Q1 being turned on, thereby causing the power supply voltage to drop.

7. The circuit according to claim 5, characterized in that The comparator U1 is used for, when the first divided voltage is less than the second divided voltage, the first output voltage outputted from the output terminal of the comparator U1 is a high level; The driving module is used to pull up the high level of the first output voltage through the first pull-up resistor R5; the base of the second transistor Q2 is turned on in response to the high level, so that the second pull-up resistor R7 pulls down the bases of the first transistor Q1 and the third transistor Q3, the first transistor Q1 is turned off in response to the low level, and the third transistor Q3 is turned on in response to the low level; The MOS is used for making the branch where the high-power resistor is located not energized in response to the first transistor Q1 being turned off.

8. The circuit according to claim 6 or 7, characterized in that The circuit further comprises: a motor M; The gate of the MOS is connected to the emitters of the first transistor Q1 and the third transistor Q3; the drain is connected to one end of the high-power resistor, and the source is grounded; The other end of the high-power resistor is connected to the power supply; one end of the motor M is connected to the power supply, and the other end is grounded; The MOS is used for driving the gate of the MOS to be turned on in response to the first transistor Q1, so that the high-power resistor works to consume the voltage of the power supply, thereby reducing the power supply voltage; When the motor M is used for braking, the motor M reversely charges the power supply to increase the power supply voltage, and the first divided voltage is not less than the second divided voltage.

9. The circuit according to claim 1, characterized in that Also includes: A protection resistor R8, one end of the protection resistor R8 is connected to the power supply, and the other end of the protection resistor R8 is grounded; It is used to prevent the power supply from being short-circuited when the MOS is turned off.

10. An electronic device, characterized in that: include: A drive circuit as claimed in any one of claims 1 to 9.

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