CN221150943U

CN221150943U - Short-circuit protection circuit based on comparator basic design

Info

Publication number: CN221150943U
Application number: CN202323104198.1U
Authority: CN
Inventors: 苏林超; 李子玉; 张永强; 李永坤
Original assignee: Qingdao Skywise Technology Co ltd
Current assignee: Qingdao Skywise Technology Co ltd
Priority date: 2023-11-17
Filing date: 2023-11-17
Publication date: 2024-06-14
Anticipated expiration: 2033-11-17

Abstract

The application relates to a short-circuit protection circuit based on a comparator base design, and relates to the field of short-circuit protection circuits. The SHORT circuit detection unit comprises a first comparator T1, wherein the first comparator T1 is electrically connected with the sampling unit, the first comparator T1 receives a current voltage value, the SHORT circuit detection unit presets a first reference voltage value, the first comparator T1 compares the current voltage value with the first reference voltage value, and if the current voltage value is larger than the first reference voltage value, the first comparator T1 outputs a LOAD-SHORT signal; the driving unit is electrically connected with the first comparator T1, and is electrically connected with the switching unit, and when the driving unit receives the LOAD-SHORT signal, the driving unit drives the switching unit to turn off the loop. The application has the effect of improving the stability and the accuracy of the short-circuit protection circuit.

Description

Short-circuit protection circuit based on comparator basic design

Technical Field

The application relates to the field of short-circuit protection circuits, in particular to a short-circuit protection circuit based on a comparator base design.

Background

Solar energy is distributed around the world and is one of the cleanest energy sources, and solar power generation is always one hot spot for energy research. Solar power generation consists of four parts: solar cell panel, battery and charge-discharge controller and load. The charge-discharge controller has the following functions: (1) Charging the electric quantity of the solar cell panel into a storage battery according to a charging mode of the storage battery; (2) managing the amount of electricity of the battery; (3) protecting the solar power generation system.

The control scheme of the controller with the short-circuit protection function in the market generally uses the operational amplifier to collect the abnormal current and then turns off the load control triode, thereby turning off the MOS tube of the loop to realize the short-circuit protection. When the load is short-circuited, a large current flows through the MOS tube, meanwhile, the operational amplifier adopts the voltage at the position of the MOS tube, the MCU calculates the voltage to reach the standard of the short-circuit current to control the first triode to be opened, the collector electrode of the first triode, namely the base electrode of the second triode, is pulled down to 0, the second triode is opened, and the collector electrode of the second triode is pulled down to 0 at the moment to turn off the load MOS.

Aiming at the related technology, the transistor is used for controlling the MOS to be turned on and turned off, the voltage difference between the base electrode and the emitter electrode of the transistor is larger than 0.6V, the transistor can act, the transistor is easily affected by the environment to generate a certain temperature drift, and the protection circuit is easy to generate errors.

Disclosure of utility model

In order to improve stability and accuracy of a short-circuit protection circuit, the application provides the short-circuit protection circuit based on a comparator base design.

The application provides a short-circuit protection circuit based on a comparator base design, which adopts the following technical scheme:

The short-circuit protection circuit based on the basic design of the comparator comprises a sampling unit, a short-circuit detection unit, a driving unit and a switching unit, wherein the sampling unit collects current voltage and outputs a current voltage value; the SHORT circuit detection unit comprises a first comparator T1, the first comparator T1 is electrically connected with the sampling unit, the first comparator T1 receives a current voltage value, the SHORT circuit detection unit presets a first reference voltage value, the first comparator T1 compares the current voltage value with the first reference voltage value, and if the current voltage value is larger than the first reference voltage value, the first comparator T1 outputs a LOAD-SHORT signal; the input end of the driving unit is electrically connected with the output end of the first comparator T1, the output end of the driving unit is electrically connected with the switching unit, and when the driving unit receives a LOAD-SHORT signal output by the first comparator T1, the driving unit drives the switching unit to turn off a loop.

By adopting the technical scheme, the short-circuit protection circuit uses the first comparator T1 to detect the short circuit in the loop, and when the circuit is short-circuited, the comparator can perform comparison operation at extremely high speed and generate corresponding output signals. Meanwhile, the comparator has good reliability and stability, can work normally under various environmental conditions, and is not easily influenced by external environment or noise.

Optionally, the negative input end of the first comparator T1 is electrically connected with a third resistor R3, the other end of the third resistor R3 is electrically connected with the sampling unit, and the current voltage value collected by the sampling unit is input to the negative input end of the first comparator T1 through the third resistor R3; the positive input end of the first comparator T1 is electrically connected with a fourth resistor R4, the other end of the fourth resistor R4 is connected with VCC, one end, far away from VCC, of the fourth resistor R4 is electrically connected with a fifth resistor R5, the other end of the fifth resistor R5 is grounded, and the first reference voltage is obtained by dividing the voltage of the fourth resistor R4 and the fifth resistor R5; the output end of the first comparator T1 is electrically connected with a seventh resistor R7, the other end of the seventh resistor R7 is electrically connected with the driving unit, and a LOAD-SHORT signal output by the first comparator T1 is output to the driving unit through the seventh resistor R7.

Through adopting above-mentioned technical scheme, two input of first comparator T1 all establish ties and have the resistance, and the series resistance can restrict the size of electric current, prevents that the too big electric current from appearing in the circuit from causing the damage to the comparator. Meanwhile, the comparator can set the voltage triggering the short-circuit protection by adjusting the threshold value, so that the flexibility of the circuit is improved.

Optionally, the SHORT circuit detection unit further includes a second comparator T2, where the second comparator T2 is electrically connected to the first comparator T1, the second comparator T2 receives the LOAD-SHORT signal output by the first comparator T1, and presets a second reference voltage value, and the second comparator T2 compares the LOAD-SHORT signal with the second reference voltage value, and if the LOAD-SHORT signal is smaller than the second reference voltage value, the second comparator T2 outputs a LOAD-EN signal; the input end of the driving unit is electrically connected with the output end of the second comparator T2, and when the driving unit receives the LOAD-EN signal output by the second comparator T2, the driving unit drives the switch unit to turn off the loop.

By adopting the technical scheme, the reliability of the short-circuit protection circuit can be improved by using the two-stage comparator. The first-stage comparator can rapidly detect short-circuit events, and the second-stage comparator can further confirm short-circuit conditions, so that false alarms and false judgments are avoided, and the reliability of the protection circuit is improved.

Optionally, the positive input end of the second comparator T2 is electrically connected with an eighth resistor R8, the other end of the eighth resistor R8 is electrically connected with the output end of the first comparator T1, and the LOAD-SHORT signal output by the first comparator T1 is input to the positive input end of the second comparator T2 through the eighth resistor R8; the negative input end of the second comparator T2 is electrically connected with a ninth resistor R9, the other end of the ninth resistor R9 is connected with VCC, one end, far away from VCC, of the ninth resistor R9 is electrically connected with a tenth resistor R10, the other end of the tenth resistor R10 is grounded, the second reference voltage is obtained by dividing the voltage between the ninth resistor R9 and the tenth resistor R10, and the output end of the second comparator T2 is electrically connected with the driving unit.

Through adopting above-mentioned technical scheme, two input of second comparator T2 all establish ties and have the resistance, and the series resistance can restrict the size of electric current, prevents that the too big electric current from appearing in the circuit from causing the damage to the comparator. Meanwhile, the input impedance of the comparator can be increased, the driving current of an input signal source is reduced, and the stability and the accuracy of an input signal are improved.

Optionally, the output end of the first comparator T1 is electrically connected with a sixth resistor R6, the other end of the sixth resistor R6 is electrically connected with a single chip microcomputer chip U1, the LOAD-SHORT signal output by the first comparator T1 is output to the single chip microcomputer chip U1 through the sixth resistor R6, and when the single chip microcomputer chip U1 receives the LOAD-SHORT signal, a LOAD-EN signal is output; the singlechip chip U1 is electrically connected with the driving unit, the singlechip chip U1 outputs a LOAD-EN signal to the driving unit, and when the driving unit receives the LOAD-EN signal, the driving unit drives the switch unit to turn off a loop.

By adopting the technical scheme, the first comparator T1 rapidly detects a SHORT-circuit event when a SHORT circuit occurs in a loop, the second comparator T2 further confirms the SHORT-circuit condition and rapidly reacts, meanwhile, the first comparator T1 outputs a LOAD-SHORT signal to the singlechip chip U1, and the singlechip chip U1 receives the LOAD-SHORT signal and outputs a LOAD-EN signal to the driving unit, so that SHORT-circuit protection is taken over, a flexible SHORT-circuit protection strategy is realized, and the adaptability and the flexibility of the circuit are improved.

Optionally, the switch unit includes a MOS transistor Q1, a source electrode of the MOS transistor Q1 is electrically connected to the sampling unit, a gate electrode of the MOS transistor Q1 is electrically connected to the driving unit, and a drain electrode of the MOS transistor Q1 is electrically connected to the load.

By adopting the technical scheme, the MOS tube has good switching performance and can be rapidly switched between on and off states. In the short-circuit protection circuit, when a short-circuit event is detected, the MOS tube can rapidly cut off circuit connection, so that large current is prevented from flowing, and damage to circuits and equipment is reduced.

Optionally, a first capacitor C1 is connected in parallel between the source and the drain of the MOS transistor Q1.

Through adopting above-mentioned technical scheme, first electric capacity C1 can make spike voltage follow and alleviate, and spike voltage can make the MOSFET get into avalanche breakdown and damage MOSFET, through parallelly connected electric capacity between the source and the drain of MOS pipe, the overvoltage that the MOSFET bore reduces in the same time, and the avalanche energy that produces reduces, and then has protected the MOS pipe.

Optionally, the sampling unit includes a first resistor R1 and a second resistor R2, one end of the first resistor R1 is grounded, the other end is electrically connected with the source electrode of the MOS transistor Q1 and one end of the third resistor R3 away from the first comparator T1, and the first resistor R1 is parallel to the second resistor R2.

By adopting the technical scheme, the circuit connection method for collecting the voltage by utilizing the first resistor R1 is simple, the cost is relatively low, the stability and the reliability are generally good, the influence of external environment is not easy to be influenced, and the collected voltage can be ensured to be more accurate. When short-circuit current flows through the loop, the resistor can generate larger heat, and the heat productivity of a single resistor can be effectively reduced through the parallel connection of the first resistor R1 and the second resistor R2, so that the risks of heat accumulation and local overheating are reduced.

Optionally, the sampling unit includes an operational amplifier T3, a negative input end of the operational amplifier T3 is electrically connected to a thirteenth resistor R13, another end of the thirteenth resistor R13 is grounded, a positive input end of the operational amplifier T3 is electrically connected to a fourteenth resistor R14, and another end of the fourteenth resistor R14 is electrically connected to an end of the first resistor R1 far away from the ground; a fifteenth resistor R15 is connected in parallel between the negative input end and the output end of the operational amplifier T3; the output end of the operational amplifier T3 is electrically connected with a sixteenth resistor R16, the operational amplifier T3 receives the CURRENT voltage value output by the first resistor R1, generates a LOAD-CURRENT signal through operational amplification, and outputs the LOAD-CURRENT signal through the sixteenth resistor R16.

By adopting the technical scheme, the operational amplifier T3 and the surrounding resistors form the same-phase amplifier circuit together, the positive input end of the operational amplifier T3 receives the current voltage value to carry out amplification operation and outputs the operation value, people can calculate the current voltage value according to the operation value output by the operational amplifier T3 and the amplification factor of the same-phase amplifier circuit, and then the current value in the current loop is obtained by combining the resistance value of the first resistor.

Optionally, a twenty-first resistor R21 is connected in series between the MOS transistor Q1 and the load, the twenty-first resistor R21 is connected in parallel with a first diode D1 and a second diode D2, anodes of the first diode D1 and the second diode D2 are electrically connected with one end, close to the switch unit, of the twenty-first resistor R21, and cathodes of the first diode D1 and the second diode D2 are electrically connected with one end, close to the load, of the twenty-first resistor R21.

By adopting the technical scheme, the resistor and the diode form a follow current protection circuit, when the load is an inductive load, after the power supply in the loop is turned off, the inductive load can continuously conduct current due to inertia of the inductive element, and a follow current phenomenon is formed. The follow current protection circuit can protect elements in the circuit from being damaged by reverse voltage, reduce the influence of follow current phenomenon on other circuit elements or devices, and improve the reliability and stability of the system.

In summary, the present application includes at least one of the following beneficial technical effects:

1. The sampling unit transmits the collected current voltage value to the short circuit detection unit, and the first comparator T1 of the short circuit detection unit compares the current voltage value with a first reference voltage value. The short-circuit protection circuit uses the first comparator T1 to detect short-circuit in the circuit, and when the circuit is short-circuited, the comparator can perform comparison operation at extremely high speed and generate corresponding output signals. Meanwhile, the comparator has good reliability and stability, can work normally under various environmental conditions, and is not easily influenced by external environment or noise;

2. The short-circuit protection circuit controls the short-circuit protection and the load switch in a hardware-software combination mode, hardware and software act simultaneously, the hardware protection acts faster, the software protection ensures that the short-circuit protection is more accurate and reliable, and devices such as a controller, a load end, a battery and the like can be protected from being damaged more quickly and accurately;

3. The resistor and the diode form a follow current protection circuit, so that elements in the circuit can be protected from being damaged by reverse voltage, the influence of follow current phenomenon on other circuit elements or devices is reduced, and the reliability and stability of the system can be improved.

Drawings

Fig. 1 is a system block diagram of a short-circuit protection circuit based on a comparator base design in accordance with an embodiment of the present application.

Fig. 2 is a schematic circuit diagram of a sampling unit according to an embodiment of the present application.

Fig. 3 is a schematic circuit diagram of a short circuit detecting unit according to an embodiment of the present application.

Fig. 4 is a schematic circuit diagram of a short circuit detection unit and a driving unit according to an embodiment of the present application.

Fig. 5 is a circuit schematic of a switching unit according to an embodiment of the application.

Reference numerals illustrate: 1. a sampling unit; 2. a short circuit detection unit; 3. a driving unit; 4. and a switching unit.

Detailed Description

In order to make the objects, technical solutions and advantages of the present application more apparent, the present application will be further described in detail with reference to the accompanying drawings 1 to 5 and examples. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the application.

The embodiment of the application discloses a short-circuit protection circuit based on a comparator base design. Referring to fig. 1, a short-circuit protection circuit based on a comparator base design includes a sampling unit 1, a short-circuit detection unit 2, a driving unit 3, and a switching unit 4. The sampling unit 1 collects current in a current loop and converts the current into a current voltage value to be output to the short circuit detection unit 2, the short circuit detection unit 2 judges whether the loop is short-circuited according to the current voltage value, when the loop is short-circuited, the short circuit detection unit 2 outputs a short circuit signal to the driving unit 3, and the driving unit 3 drives the switching unit 4 to disconnect the current loop, so that short circuit protection is realized.

Referring to fig. 2, the sampling unit 1 includes a first resistor R1 and a second resistor R2, the first resistor R1 is connected in series in a loop, one end of the first resistor R1 is grounded, the other end is electrically connected with the short circuit detection unit 2 and the switching unit 4, the second resistor R2 is connected in parallel to two ends of the first resistor R1, and the sampling unit 1 collects a current voltage and outputs the current voltage value. The first resistor R1 is electrically connected with a fourteenth resistor R14 far away from the grounding end, the other end of the fourteenth resistor R14 is provided with an operational amplifier T3, the positive input end of the operational amplifier T3 is electrically connected with the fourteenth resistor R14, the positive input end of the operational amplifier T3 is electrically connected with a seventeenth resistor R17 and an eleventh capacitor C11, and the other ends of the seventeenth resistor R17 and the eleventh capacitor C11 are grounded. The negative input end of the operational amplifier T3 is electrically connected with a thirteenth resistor R13, the other end of the thirteenth resistor R13 is grounded, and the negative input end and the positive input end of the operational amplifier T3 are connected in parallel with a ninth capacitor C9. A fifteenth resistor R15 is connected in parallel between the negative input end and the output end of the operational amplifier T3, and a tenth capacitor C10 is connected in parallel at two ends of the fifteenth resistor R15; the output end of the operational amplifier T3 is electrically connected to a sixteenth resistor R16, the other end of the sixteenth resistor R16 is electrically connected to a twelfth capacitor C12, and the other end of the twelfth capacitor C12 is grounded. The operational amplifier T3 receives the CURRENT voltage value output by the first resistor R1, generates a LOAD-CURRENT signal through operational amplification, and outputs the LOAD-CURRENT signal through a sixteenth resistor R16.

Referring to fig. 3, the short circuit detecting unit 2 includes a first comparator T1, a negative input end of the first comparator T1 is electrically connected with a third resistor R3 and a second capacitor C2, another end of the second capacitor C2 is grounded, another end of the third resistor R3 is electrically connected with one end of the first resistor R1 far away from the ground, and a current voltage value collected by the sampling unit 1 is input to the negative input end of the first comparator T1 through the third resistor R3. The positive input end of the first comparator T1 is electrically connected with a fourth resistor R4, the other end of the fourth resistor R4 is connected with VCC, one end, far away from VCC, of the fourth resistor R4 is electrically connected with a fifth resistor R5, the other end of the fifth resistor R5 is grounded, the fourth resistor R4 and the fifth resistor R5 are divided to obtain a first reference voltage, and the two ends of the fifth resistor R5 are connected with a third capacitor C3 in parallel. The first comparator T1 receives the current voltage value, the first comparator T1 compares the current voltage value with a first reference voltage value, and when the current voltage value is larger than the first reference voltage value, the first comparator T1 outputs a LOAD-SHORT signal.

Referring to fig. 3, an output end of the first comparator T1 is electrically connected to a sixth resistor R6 and a seventh resistor R7, another end of the sixth resistor R6 is electrically connected to the single chip microcomputer chip U1, another end of the seventh resistor R7 is electrically connected to an eighth resistor R8, a fourth capacitor C4 and VCC, another end of the fourth capacitor C4 is grounded, another end of the eighth resistor R8 is electrically connected to a fifth capacitor C5 and the second comparator T2, and another end of the fifth capacitor C5 is grounded. The eighth resistor R8 is electrically connected to the positive input terminal of the second comparator T2, and the LOAD-SHORT signal output from the first comparator T1 is input to the positive input terminal of the second comparator T2 through the eighth resistor R8. The negative input end of the second comparator T2 is electrically connected with a ninth resistor R9, the other end of the ninth resistor R9 is connected with VCC, one end, far away from VCC, of the ninth resistor R9 is electrically connected with a tenth resistor R10, the other end of the tenth resistor R10 is grounded, the two ends of the tenth resistor R10 are connected with a sixth capacitor C6 in parallel, the voltage division between the ninth resistor R9 and the tenth resistor R10 is conducted to obtain a second reference voltage, the output end of the second comparator T2 is electrically connected with a twelfth resistor R12, and the other end of the twelfth resistor R12 is grounded. The output end of the second comparator T2 is electrically connected with the input end of the driving unit 3, the second comparator T2 receives the LOAD-SHORT signal and compares the LOAD-SHORT signal with a second reference voltage value, and when the LOAD-SHORT signal is larger than the first reference voltage value, the second comparator T2 outputs a LOAD-EN signal to the driving unit 3.

Referring to fig. 4, the single chip microcomputer chip U1 is electrically connected with the sixth resistor R6, the LOAD-SHORT signal output by the first comparator T1 is output to the input end of the single chip microcomputer chip U1 through the sixth resistor R6, and when the single chip microcomputer chip U1 receives the LOAD-SHORT signal, the output end of the single chip microcomputer chip U1 outputs the LOAD-EN signal. The output end of the singlechip chip U1 is electrically connected with an eleventh resistor R11, the other end of the eleventh resistor R11 is connected with the input end of the driving unit 3, and a LOAD-EN signal is transmitted to the driving unit 3 through the eleventh resistor R11.

Referring to fig. 4, the driving unit 3 includes a driving chip EG27324, the output end of the second comparison T2 and one end of the eleventh resistor R11 far away from the singlechip chip U1 are electrically connected to the 2 nd pin of the driving chip EG27324, the 3 rd pin of the driving chip EG27324 is grounded, the 6 th pin of the driving chip EG27324 is connected to VCC, the seventh capacitor C7 and the eighth capacitor C8, and the seventh capacitor C7 and the eighth capacitor C8 are grounded far away from one end of VCC. The 7 th pin of the driving chip EG27324 is electrically connected to the twentieth resistor R20, and the other end of the twentieth resistor R20 is electrically connected to the switching unit 4. When the 2 nd pin of the driving chip EG27324 receives the LOAD-EN signal, the 7 th pin of the driving chip EG27324 outputs a LOAD-CTRL signal, which is output to the switching unit 4 through the twentieth resistor R20.

Referring to fig. 5, the switch unit 4 includes a MOS transistor Q1, a gate of the MOS transistor Q1 is electrically connected to a nineteenth resistor R19, and another end of the nineteenth resistor R19 is electrically connected to one end of the twentieth resistor R20 away from the driving chip EG 27324. The source electrode of the MOS tube Q1 is electrically connected with one end, far away from the ground, of the first resistor R1, the source electrode of the MOS tube Q1 is electrically connected with an eighteenth resistor R18, and the other end of the eighteenth resistor R18 is electrically connected with one end, far away from the MOS tube Q1, of a nineteenth resistor R19. The drain electrode of the MOS tube Q1 is electrically connected with a first capacitor C1 and a twenty-first resistor R21, the other end of the first capacitor C1 is electrically connected with the source electrode of the MOS tube Q1, the other end of the twenty-first resistor R21 is connected with a load, the twenty-first resistor R21 is connected with a first diode D1 and a second diode D2 in parallel, the positive electrode of the first diode D1 and the positive electrode of the second diode D2 are electrically connected with one end, close to the MOS tube Q1, of the twenty-first resistor R21, and the negative electrode of the first diode D1 and the negative electrode of the second diode D2 are electrically connected with one end, close to the load, of the twenty-first resistor R21. The LOAD-CTRL signal enters the grid electrode of the MOS tube Q1 through a nineteenth resistor R19, and when the MOS tube Q1 receives the LOAD-CTRL signal, the MOS tube Q1 is turned off.

The implementation principle of the short-circuit protection circuit based on the basic design of the comparator in the embodiment of the application is as follows: when the circuit is short-circuited, the circuit current is increased, the voltage of one end of the first resistor R1 far away from the ground is increased, the first comparator T1 of the short-circuit detection unit 2 is used for rapidly detecting a short-circuit event, the second comparator T2 is used for further confirming the short-circuit condition, meanwhile, the first comparator T1 outputs a signal to the single chip microcomputer chip U1, the second comparator T2 is used for rapidly outputting a LOAD-EN signal to the driving unit 3 after confirming the short-circuit, the driving unit 3 drives the MOS tube Q1 to be turned off, the short-circuit protection function is realized, and the single chip microcomputer chip U1 is used for outputting the LOAD-EN signal to the driving unit 3 after receiving the short-circuit signal, so that the short-circuit protection of hardware is taken over. The short-circuit protection circuit uses the first comparator T1 to detect short-circuit in the loop, the comparator can perform comparison operation at extremely high speed when short-circuit occurs, meanwhile, the comparator has good reliability and stability, can work normally under various environmental conditions, and is not easy to be influenced by external environment or noise.

The foregoing description of the preferred embodiments of the application is not intended to limit the scope of the application in any way, including the abstract and drawings, in which case any feature disclosed in this specification (including abstract and drawings) may be replaced by alternative features serving the same, equivalent purpose, unless expressly stated otherwise. That is, each feature is one example only of a generic series of equivalent or similar features, unless expressly stated otherwise.

Claims

1. A short-circuit protection circuit based on comparator basic design is characterized in that: the device comprises a sampling unit (1), a short circuit detection unit (2), a driving unit (3) and a switching unit (4), wherein the sampling unit (1) collects current voltage and outputs a current voltage value; the SHORT circuit detection unit (2) comprises a first comparator T1, the first comparator T1 is electrically connected with the sampling unit (1), the first comparator T1 receives a current voltage value, the SHORT circuit detection unit (2) presets a first reference voltage value, the first comparator T1 compares the current voltage value with the first reference voltage value, and if the current voltage value is larger than the first reference voltage value, the first comparator T1 outputs a LOAD-SHORT signal; the input end of the driving unit (3) is electrically connected with the output end of the first comparator T1, the output end of the driving unit (3) is electrically connected with the switching unit (4), and when the driving unit (3) receives a LOAD-SHORT signal output by the first comparator T1, the driving unit (3) drives the switching unit (4) to turn off a loop.

2. A short-circuit protection circuit based on a comparator base design according to claim 1, characterized in that: the negative input end of the first comparator T1 is electrically connected with a third resistor R3, the other end of the third resistor R3 is electrically connected with the sampling unit (1), and the current voltage value acquired by the sampling unit (1) is input to the negative input end of the first comparator T1 through the third resistor R3; the positive input end of the first comparator T1 is electrically connected with a fourth resistor R4, the other end of the fourth resistor R4 is connected with VCC, one end, far away from VCC, of the fourth resistor R4 is electrically connected with a fifth resistor R5, the other end of the fifth resistor R5 is grounded, and the first reference voltage is obtained by dividing the voltage of the fourth resistor R4 and the fifth resistor R5; the output end of the first comparator T1 is electrically connected with a seventh resistor R7, the other end of the seventh resistor R7 is electrically connected with the driving unit (3), and a LOAD-SHORT signal output by the first comparator T1 is output to the driving unit (3) through the seventh resistor R7.

3. A short-circuit protection circuit based on a comparator base design according to claim 1, characterized in that: the SHORT circuit detection unit (2) further comprises a second comparator T2, the second comparator T2 is electrically connected with the first comparator T1, the second comparator T2 receives a LOAD-SHORT signal output by the first comparator T1, a second reference voltage value is preset, the second comparator T2 compares the LOAD-SHORT signal with the second reference voltage value, and if the LOAD-SHORT signal is smaller than the second reference voltage value, the second comparator T2 outputs a LOAD-EN signal; the input end of the driving unit (3) is electrically connected with the output end of the second comparator T2, and when the driving unit (3) receives a LOAD-EN signal output by the second comparator T2, the driving unit (3) drives the switching unit (4) to turn off a loop.

4. A short-circuit protection circuit based on a comparator base design according to claim 3, characterized in that: the positive input end of the second comparator T2 is electrically connected with an eighth resistor R8, the other end of the eighth resistor R8 is electrically connected with the output end of the first comparator T1, and a LOAD-SHORT signal output by the first comparator T1 is input to the positive input end of the second comparator T2 through the eighth resistor R8; the negative input end of the second comparator T2 is electrically connected with a ninth resistor R9, the other end of the ninth resistor R9 is connected with VCC, one end, far away from VCC, of the ninth resistor R9 is electrically connected with a tenth resistor R10, the other end of the tenth resistor R10 is grounded, the second reference voltage is obtained by dividing the voltage between the ninth resistor R9 and the tenth resistor R10, and the output end of the second comparator T2 is electrically connected with the driving unit (3).

5. A short-circuit protection circuit based on a comparator base design according to claim 3, characterized in that: the output end of the first comparator T1 is electrically connected with a sixth resistor R6, the other end of the sixth resistor R6 is electrically connected with a single chip microcomputer chip U1, a LOAD-SHORT signal output by the first comparator T1 is output to the single chip microcomputer chip U1 through the sixth resistor R6, and a LOAD-EN signal is output when the single chip microcomputer chip U1 receives the LOAD-SHORT signal; the singlechip chip U1 is electrically connected with the driving unit (3), the singlechip chip U1 outputs a LOAD-EN signal to the driving unit (3), and when the driving unit (3) receives the LOAD-EN signal, the driving unit (3) drives the switching unit (4) to turn off a loop.

6. A short-circuit protection circuit based on a comparator base design according to claim 2, characterized in that: the switch unit (4) comprises a MOS tube Q1, a source electrode of the MOS tube Q1 is electrically connected with the sampling unit (1), a grid electrode of the MOS tube Q1 is electrically connected with the driving unit (3), and a drain electrode of the MOS tube Q1 is electrically connected with a load.

7. The short-circuit protection circuit based on the comparator base design of claim 6, wherein: a first capacitor C1 is connected in parallel between the source and the drain of the MOS transistor Q1.

8. The short-circuit protection circuit based on the comparator base design of claim 6, wherein: the sampling unit (1) comprises a first resistor R1 and a second resistor R2, one end of the first resistor R1 is grounded, the other end of the first resistor R1 is electrically connected with the source electrode of the MOS tube Q1 and one end of the third resistor R3, which is far away from the first comparator T1, and the second resistor R2 is connected with the first resistor R1 in parallel.

9. The short-circuit protection circuit based on the comparator base design of claim 8, wherein: the sampling unit (1) comprises an operational amplifier T3, wherein a negative number input end of the operational amplifier T3 is electrically connected with a thirteenth resistor R13, the other end of the thirteenth resistor R13 is grounded, a positive input end of the operational amplifier T3 is electrically connected with a fourteenth resistor R14, and the other end of the fourteenth resistor R14 is electrically connected with one end, far away from the ground, of the first resistor R1; a fifteenth resistor R15 is connected in parallel between the negative input end and the output end of the operational amplifier T3; the output end of the operational amplifier T3 is electrically connected with a sixteenth resistor R16, the operational amplifier T3 receives the CURRENT voltage value output by the first resistor R1, generates a LOAD-CURRENT signal through operational amplification, and outputs the LOAD-CURRENT signal through the sixteenth resistor R16.

10. The short-circuit protection circuit based on a comparator base design of claim 6, comprising: the MOS tube Q1 is connected with a load in series with a twenty-first resistor R21, the twenty-first resistor R21 is connected with a first diode D1 and a second diode D2 in parallel, the positive poles of the first diode D1 and the second diode D2 are electrically connected with one end, close to the switch unit (4), of the twenty-first resistor R21, and the negative poles of the first diode D1 and the second diode D2 are electrically connected with one end, close to the load, of the twenty-first resistor R21.