Overcurrent protection circuit and method, storage medium and electronic equipment

Abstract

The embodiment of the invention provides an overcurrent protection circuit and method, storage equipment and electronic equipment, and relates to the technical field of overcurrent protection. The overcurrent protection circuit comprises a power supply unit, a control unit and a USB port. The output end of the power supply unit is connected with the power input end of the USB port through the control unit so as to supply power to the USB port; wherein the control unit is used for detecting the output current of the power supply unit and cutting off power supply to the USB port when the output current is greater than a preset threshold value. According to the invention, the problem that rapid and large-amplitude current is generated at the USB port at the moment of power-on when the USB port is short-circuited is solved, so that damage to a power supply and circuit elements is avoided.

Description

Technical Field

[0001] The present invention relates to the field of overcurrent protection technology, and in particular to an overcurrent protection circuit, method, storage medium and electronic equipment. Background Art

[0002] In the prior art, when a USB port circuit port is short-circuited, the USB port circuit will generate a fast and large current at the moment of power-on, that is, a current surge phenomenon occurs. At this time, the current may instantly exceed the circuit current safety threshold, thereby causing damage to the USB port circuit, damaging the components on the USB port circuit, and causing the system unit equipped with the USB port circuit to malfunction and fail to work normally. Summary of the invention

[0003] The present invention provides an overcurrent protection circuit, method, storage medium and electronic device, which detect the input current of a USB port through a control unit, and cut off the power supply to the USB port when the input current of the USB port is greater than a preset threshold value, so as to solve the problem that when a short circuit occurs in the USB port, or when an external device is connected and the external device is a non-pure resistance load with a capacitive element, a fast and large current is generated at the USB port at the moment of power-on, thereby avoiding damage to the power supply and circuit elements.

[0004] The embodiments of the present invention can be implemented as follows:

[0005] In a first aspect, an overcurrent protection circuit is provided, the overcurrent protection circuit comprising: a power supply unit, a control unit, and a USB port;

[0006] The output end of the power supply unit is connected to the power input end of the USB port through the control unit, so as to supply power to the USB port; wherein the control unit is used to detect the output current of the power supply unit, and when the output current is greater than a preset threshold, cut off the power supply to the USB port.

[0007] Furthermore, the control unit includes an acquisition circuit, a main control module and an execution module;

[0008] The acquisition circuit is respectively connected to the power supply unit, the main control module and the USB port to detect the output current of the power supply unit;

[0009] The main control module is also connected to the execution module to output a first control signal to the execution module when the output current is greater than a preset threshold;

[0010] The execution module is also connected to the power supply unit to cut off the power supply to the USB port according to the first control signal.

[0011] Furthermore, the acquisition circuit includes: a sampling resistor and a sampling module; the sampling resistor is respectively connected to the power supply unit, the USB port and the sampling module; the output end of the sampling module is connected to the main control module;

[0012] The sampling module detects the output current of the sampling resistor to detect the output current of the power supply unit.

[0013] Further, the sampling module includes an operational amplifier, a first resistor, a second resistor, a third resistor and a fourth resistor;

[0014] The positive phase input terminal of the operational amplifier is respectively connected to the first end of the first resistor and the second resistor; the second end of the first resistor is connected to the first end of the sampling resistor; the second end of the second resistor is grounded; the negative phase input terminal of the operational amplifier is respectively connected to the first end of the third resistor and the fourth resistor; the second end of the third resistor is connected to the second end of the sampling resistor; the second end of the fourth resistor is connected to the output terminal of the operational amplifier.

[0015] Furthermore, the resistance values ​​of the first resistor and the third resistor are equal; and the resistance values ​​of the second resistor and the fourth resistor are equal.

[0016] Further, the execution module includes a transistor; the control end of the transistor is connected to the main control module to cut off the power supply to the USB port according to the first control signal;

[0017] The first end of the transistor is connected to the power supply unit; the second end of the transistor is grounded.

[0018] Furthermore, the overcurrent protection circuit also includes a pull-up resistor;

[0019] The first end of the pull-up resistor is connected to the power supply unit; the second end of the pull-up resistor is connected to the first end of the transistor.

[0020] Furthermore, the control unit also includes a current limiting resistor;

[0021] The first end of the current limiting resistor is connected to the main control module; the second end of the current limiting resistor is connected to the execution module.

[0022] Furthermore, the overcurrent protection circuit also includes a filtering unit;

[0023] The first end of the filter unit is connected to the input end of the USB port; the second end of the filter unit is connected to the ground end of the USB port.

[0024] Further, the filtering unit includes a first capacitor and a second capacitor;

[0025] The first end of the first capacitor is connected to the first end of the second capacitor and the ground end of the USB port respectively; the second end of the first capacitor is connected to the second end of the second capacitor and the control unit respectively.

[0026] In a second aspect, an overcurrent protection control method is applied to a control unit of the overcurrent protection circuit, wherein the overcurrent protection circuit further includes a power supply unit and a USB port, and the overcurrent protection control method includes:

[0027] Obtaining an output current of the power supply unit;

[0028] The output current of the power supply unit is detected, and when the output current is greater than a preset threshold, the power supply to the USB port is cut off.

[0029] In a third aspect, a storage medium stores a computer program, which, when executed by a processor, implements the overcurrent protection control method described in the second aspect.

[0030] In a fourth aspect, an electronic device comprises the overcurrent protection circuit described in any one of the first aspects above.

[0031] The beneficial effects of the embodiments of the present invention include, for example:

[0032] An overcurrent protection circuit includes a power supply unit, a control unit, and a USB port; the output end of the power supply unit is connected to the power input end of the USB port through the control unit to supply power to the USB port; wherein the control unit is used to detect the output current of the power supply unit, and when the output current is greater than a preset threshold, the power supply to the USB port is cut off. This solves the problem that when a short circuit occurs in the USB port, a fast and large current will be generated at the USB port at the moment of power on, thereby avoiding damage to the power supply and circuit components. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0034] Figure 1 This is one of the system structure diagrams of an overcurrent protection circuit provided in an embodiment of the present application.

[0035] Figure 2The present invention provides a second schematic diagram of the system structure of an overcurrent protection circuit according to an embodiment of the present application.

[0036] Figure 3 The third system structure diagram of an overcurrent protection circuit provided in an embodiment of the present application.

[0037] Figure 4 Schematic diagram of the circuit structure of the sampling circuit in the embodiment of the present application.

[0038] Figure 5 Schematic diagram of the circuit structure of the execution module in the embodiment of the present application.

[0039] Figure 6 This is one of the circuit structure schematic diagrams of an overcurrent protection circuit in an embodiment of the present application.

[0040] Figure 7 A schematic diagram of the circuit structure of another overcurrent protection circuit provided in an embodiment of the present application.

[0041] Figure 8 A fourth system structure diagram of an overcurrent protection circuit provided in an embodiment of the present application.

[0042] Fig. 9 Schematic diagram of the circuit structure of the filter unit in the embodiment of the present application.

[0043] Fig.10 The second circuit structure schematic diagram of an overcurrent protection circuit provided in an embodiment of the present application.

[0044] Fig.11 A schematic diagram of the steps of an overcurrent protection method provided in an embodiment of the present application.

[0045] Icon: 100-overcurrent protection circuit; 101-power supply unit; 102-control unit; 103-USB port; 104-filter unit; 201-acquisition circuit; 202-main control module; 203-execution module. DETAILED DESCRIPTION

[0046] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0047] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0048] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0049] In the description of the present invention, it should be noted that if the terms "upper", "lower", "inside", "outside", etc. appear to indicate an orientation or position relationship, they are based on the orientation or position relationship shown in the accompanying drawings, or are the orientation or position relationship in which the product of the invention is usually placed when used. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0050] In addition, the terms “first”, “second”, etc., if used, are merely used to distinguish between the descriptions and should not be understood as indicating or implying relative importance.

[0051] It should be noted that, in the absence of conflict, the features in the embodiments of the present invention may be combined with each other.

[0052] As described in the background art, when the USB port circuit port is short-circuited, the USB port circuit will generate a fast and large current at the moment of power-on, that is, a current surge phenomenon occurs. At this time, the current may instantly exceed the circuit current safety threshold, thereby damaging the USB port circuit, damaging the components on the USB port circuit, and causing the system unit equipped with the USB port circuit to malfunction and fail to work normally. Or when the USB port circuit is connected to an external device and the device is not a pure resistance load and has capacitive components, the above current surge phenomenon will also occur.

[0053] Based on this, an overcurrent protection circuit, method, storage medium and electronic device are provided in the embodiments of the present application to solve the problem that when a short circuit occurs in the USB port, a fast and large current will be generated at the USB port at the moment of power-on, thereby reducing the current surge phenomenon to avoid damage to the power supply and circuit components.

[0054] Please refer to Figure 1 In a first aspect, an embodiment of the present application provides an overcurrent protection circuit 100, the overcurrent protection circuit 100 comprising: a power supply unit 101, a control unit 102, and a USB port 103;

[0055] The output end of the power supply unit 101 is connected to the power input end of the USB port 103 through the control unit 102, and is used to supply power to the USB port 103; wherein the control unit 102 is used to detect the output current of the power supply unit 101, and when the output current is greater than a preset threshold, cut off the power supply to the USB port 103.

[0056] In the embodiment of the present application, the power supply unit 101 detects the output current of the power supply unit 101 through the control unit 102, and when the output current of the power supply unit 101 is greater than a preset threshold, the power supply to the USB port 103 is cut off, so as to avoid the problem of rapid and large current being generated at the USB port 103 at the moment of power-on when a short circuit occurs in the USB port 103, or the current surge phenomenon generated when the USB port 103 circuit is connected to an external device and the device is not a pure resistive load and has capacitive elements, so as to avoid damage to the power supply and circuit elements.

[0057] For further information, see Figure 2 In an achievable embodiment, the control unit 102 includes an acquisition circuit 201, a main control module 202 and an execution module 203;

[0058] The acquisition circuit 201 is respectively connected to the power supply unit 101, the main control module 202, and the USB port 103 to detect the output current of the power supply unit 101;

[0059] The main control module 202 is also connected to the execution module 203 to output a first control signal to the execution module 203 when the output current is greater than a preset threshold;

[0060] The execution module 203 is further connected to the power supply unit 101 to cut off the power supply to the USB port 103 according to the first control signal.

[0061] In this embodiment, the acquisition circuit 201 can set a sampling resistor at the output end of the power supply unit 101 and the power input end of the USB port 103, so as to use the voltage / current of the sampling resistor set on the main line as the judgment basis of the control unit to determine the output current of the power supply unit 101, and cut off the power supply to the USB port 103 when the output current is greater than a preset threshold value; based on this, after obtaining the voltage / current of the sampling resistor, the main control module 202 can output a control signal to the execution module 203 according to the judgment threshold set by it when the output current is greater than the preset threshold value, and the control signal can be a high / low level. For example, when the output current is greater than the preset threshold value, a first control signal, i.e., a high level signal, can be output to the execution module 203 to drive the execution module 203 to cut off the power supply to the USB port 103 according to the high level signal.

[0062] Similarly, when the output current is lower than a preset threshold, a second control signal may be output to the execution module 203, and the control signal may be a low level. For example, when the output current is greater than the preset threshold, a second control signal, i.e., a low level signal, is output to the execution module 203 to drive the execution module 203 to conduct normally according to the low level signal to supply power to the USB port 103.

[0063] In the embodiment of the present application, the method of obtaining the sampling value by the main control module 202 and outputting a control signal to the execution module 203 when the output current is greater than the preset threshold value is not within the protection scope of the present application, that is, the present application does not judge the determination method, as long as it can be achieved that the high and low level outputs of the main control module 202 can be determined based on the sampling value.

[0064] For further information, see Figure 3 In an achievable embodiment, the acquisition circuit 201 includes: a sampling resistor and a sampling module; the sampling resistor is respectively connected to the power supply unit 101, the USB port 103 and the sampling module; the output end of the sampling module is connected to the main control module 202;

[0065] The sampling module detects the output current of the sampling resistor to detect the output current of the power supply unit 101 .

[0066] For further information, see Figure 4 In an achievable embodiment, the sampling module includes an operational amplifier U1, a first resistor R1, a second resistor R2, a third resistor R3 and a fourth resistor R4.

[0067] The positive phase input terminal of the operational amplifier U1 is respectively connected to the first end of the first resistor R1 and the second resistor R2; the second end of the first resistor R1 is connected to the first end of the sampling resistor R5; the second end of the second resistor R2 is grounded; the negative phase input terminal of the operational amplifier U1 is respectively connected to the first end of the third resistor R3 and the fourth resistor R4; the second end of the third resistor R3 is connected to the second end of the sampling resistor; the second end of the fourth resistor R4 is connected to the output terminal of the operational amplifier U1.

[0068] Furthermore, the resistance values ​​of the first resistor R1 and the third resistor R3 are equal; the resistance values ​​of the second resistor R2 and the fourth resistor R4 are equal.

[0069] In this embodiment, when no current flows through the positive phase input terminal and the negative phase input terminal of the operational amplifier, that is, the positive phase input terminal and the negative phase input terminal are equivalent to a short circuit, that is, in a false short circuit state. In this state, the third resistor R3 and the fourth resistor R4 corresponding to the negative phase input terminal of the operational amplifier U1 have the same current. Similarly, the first resistor R1 and the second resistor R2 at the positive phase input terminal of the operational amplifier U1 also have the same current. Then the voltage on the corresponding sampling resistor can satisfy:

[0070]

[0071] Among them, V 1 is the voltage on the left side of the sampling resistor, V 2 is the voltage on the right side of the sampling resistor, V x is the upper voltage of resistor R1, V y is the voltage on the upper side of resistor R3, V out is the output voltage of the operational amplifier.

[0072] Furthermore, due to the false short circuit state, V x =V y , that is, the voltage on the upper side of the resistor R1 is equal to the voltage on the upper side of the resistor R3. According to Ohm's law, the voltage of the sampling resistor can be:

[0073] V=i*R3=V 1 -V 2 ;

[0074] Substituting into the above formula, we can get:

[0075]

[0076] Among them, since the resistance values ​​of the first resistor R1 and the third resistor R3 are equal; the resistance values ​​of the second resistor R2 and the fourth resistor R4 are equal, the following can be simplified:

[0077]

[0078] It can be understood that in the embodiment of the present application, the voltage of the sampling resistor set on the main line can be obtained according to the above-mentioned sampling module to determine whether the output current of the power supply unit 101 is within the set judgment threshold. When the output current is greater than the preset threshold, a control signal is output to the execution module 203.

[0079] Furthermore, the sampling module obtains the voltage on the acquisition resistor R5 in real time and transmits it to the main control module 202. In a feasible embodiment, the main control module 202 may be an MCU chip, and the output end of the operational amplifier may be connected to the ADC pin on the MCU chip. The sampling voltage of the sampling resistor obtained by the ADC pin, if the set judgment threshold is current, the resistance of the sampling resistor may be fixed on this basis, and then the sampling voltage determined by the sampling module is used to obtain the current of the sampling resistor to determine whether it is within the preset current range.

[0080] For further information, see Figure 5 In an achievable embodiment, the execution module 203 includes a transistor Q1; the control end of the transistor Q1 is connected to the main control module 202 to cut off the power supply to the USB port;

[0081] A first end of the transistor Q1 is connected to the power supply unit 101 ; a second end of the transistor Q1 is grounded.

[0082] In this embodiment, after obtaining the voltage / current of the sampling resistor, the main control module 202 can transmit a control signal to the control end of the transistor Q1 according to the judgment threshold set by it, when the output current is greater than the preset threshold. For example, when the output current is greater than the preset threshold, the first control signal, i.e., a high-level signal, can be output to the execution module 203. At this time, the transistor Q1 is turned on and the power supply to the USB port 103 is cut off.

[0083] Similarly, when the output current is lower than a preset threshold, a second control signal can be output to the execution module 203, and the control signal can be a low level. For example, when the output current is greater than the preset threshold, a second control signal, i.e., a low level signal, is output to the execution module 203. At this time, the transistor Q1 is turned off to supply power to the USB port 103.

[0084] See also Figure 6 , further, the overcurrent protection circuit 100 also includes a pull-up resistor R6;

[0085] A first end of the pull-up resistor R6 is connected to the power supply unit 101 ; a second end of the pull-up resistor R6 is connected to a first end of the transistor.

[0086] Exemplarily, when the power supply unit 101 is 5V, when the output current is less than a preset threshold, the MCU outputs a low-level signal to the transistor Q1. At this time, the transistor Q1 is cut off, and the output terminal OUT of the power supply unit 101 is pulled up to a high level of 5V due to the pull-up resistor. It can be understood that the output terminal OUT of the power supply unit 101 is adjusted to a high-level state through the pull-up resistor R6, so that when the output current is less than the preset threshold, the output terminal OUT of the power supply unit 101 supplies power to the USB port 103.

[0087] When the output current is greater than a preset threshold, the MCU outputs a high level signal to the transistor Q1 , and the transistor Q1 is turned on, the output terminal OUT of the power supply unit 101 is grounded, and the power supply unit 101 stops supplying power to the USB port 103 .

[0088] Furthermore, the control unit 102 also includes a current limiting resistor R7;

[0089] A first end of the current limiting resistor R7 is connected to the main control module 202 ; a second end of the current limiting resistor is connected to the execution module 203 .

[0090] In another achievable embodiment, the control unit 102 may be a current limiting power distribution chip. For example, in the embodiment of the present application, please refer to Figure 7 The current detection terminal FLT and the power input terminal IN of the current limiting power distribution chip are both connected to the output terminal of the power supply unit 101; the current output terminal OUT of the current limiting power distribution chip is connected to the power input terminal of the USB port 103, wherein the enable terminal EN of the current limiting power distribution chip is connected to the power supply to provide a high-level driving signal for the enable terminal of the current limiting power distribution chip. In a feasible embodiment, the enable terminal of the current limiting power distribution chip can be connected to the power supply through a pull-up resistor R8 to maintain the current limiting power distribution chip in a high-level conduction state, and the power supply can be 5V.

[0091] Furthermore, the current detection terminal FLT of the current limiting power distribution chip can also be connected to the output terminal of the power supply unit 101 through a current limiting resistor R9.

[0092] In this embodiment, the current detection terminal FLT can directly perform a threshold judgment after acquiring the current, that is, to determine the output current of the power supply unit 101 in the current limiting power distribution chip, so as to cut off the power supply to the USB port 103 when the output current is greater than the preset threshold.

[0093] For further information, see Figure 8 , the overcurrent protection circuit 100 further includes a filtering unit 104;

[0094] A first end of the filter unit 104 is connected to an input end of the USB port 103 ; a second end of the filter unit 104 is connected to a ground end of the USB port 103 .

[0095] For further information, see Fig. 9 , the filtering unit 104 includes a first capacitor C1 and a second capacitor C2;

[0096] The first end of the first capacitor C1 is respectively connected to the first end of the second capacitor C2 and the ground end of the USB port 103; the second end of the first capacitor C1 is respectively connected to the second end of the second capacitor C2, the control unit, and the input end of the USB port 103. In an achievable embodiment, the first capacitor C1 or the second capacitor C2 may be an electrolytic capacitor.

[0097] In an achievable embodiment, the specific circuit diagram of the overcurrent protection circuit 100 is shown in FIG. Fig.10 , where D+ / D- are signal pins with opposite polarities on the USB port 103 .

[0098] In summary, an overcurrent protection circuit 100 is provided in an embodiment of the present application, and the overcurrent protection circuit 100 includes a power supply unit 101, a control unit 102, and a USB port 103; the output end of the power supply unit 101 is connected to the power input end of the USB port through the control unit 102 to supply power to the USB port 103; wherein the control unit 102 is used to detect the output current of the power supply unit 101, and when the output current is greater than a preset threshold, cut off the power supply to the USB port 103. This solves the problem that when a short circuit occurs in the USB port 103, a fast and large current will be generated at the USB port 103 at the moment of power-on, thereby avoiding damage to the power supply and circuit components.

[0099] In a second aspect, an overcurrent protection control method is applied to a control unit 102 of an overcurrent protection circuit 100, wherein the overcurrent protection circuit 100 further includes a power supply unit 101 and a USB port 103. Fig.11 , the overcurrent protection control method comprises the following steps:

[0100] S1, obtaining the output current of the power supply unit 101;

[0101] S2, detecting the output current of the power supply unit 101, and cutting off the power supply to the USB port 103 when the output current is greater than a preset threshold.

[0102] An embodiment of the present application provides an overcurrent protection control method, which is applied to the control unit 102 of the overcurrent protection circuit 100 to solve the problem that when a short circuit occurs in the USB port 103, a fast and large current will be generated at the USB port 103 at the moment of power-on, thereby avoiding damage to the power supply and circuit components.

[0103] In a third aspect, a storage medium stores a computer program, which implements the overcurrent protection control method of the second aspect when executed by a processor. The storage medium stores computer instructions and programs, which execute the method of the above embodiment when read and run. The storage medium may include a memory, a flash memory, a register, or a combination thereof.

[0104] An embodiment of the present application provides a storage medium having a computer program stored thereon. When the computer program is executed by a processor, the overcurrent protection control method of the second aspect described above is implemented. The computer program includes all technical means and technical effects of the overcurrent protection control method of the second aspect described above, that is, the problem that when a short circuit occurs in the USB port 103, a fast and large current will be generated at the USB port 103 at the moment of power-on can be solved, thereby avoiding damage to the power supply and circuit components.

[0105] In a fourth aspect, an electronic device includes the overcurrent protection circuit 100 of any one of the first aspects above.

[0106] An embodiment of the present application provides an electronic device, comprising all the technical features and technical effects of the overcurrent protection circuit 100 of any one of the first aspects above.

[0107] In summary, the embodiments of the present application provide an overcurrent protection circuit 100, a method, a storage medium and an electronic device, wherein an overcurrent protection circuit 100 includes a power supply unit 101, a control unit 102 and a USB port 103; the output end of the power supply unit 101 is connected to the power input end of the USB port through the control unit 102 to supply power to the USB port 103; wherein the control unit 102 is used to detect the output current of the power supply unit 101, and when the output current is greater than a preset threshold, cut off the power supply to the USB port 103. This solves the problem that when a short circuit occurs in the USB port 103, a fast and large current will be generated at the USB port 103 at the moment of power-on, thereby avoiding damage to the power supply and circuit components.

[0108] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be based on the protection scope of the claims.

Claims

1. An overcurrent protection circuit, It is characterized in that The overcurrent protection circuit comprises: a power supply unit, a control unit, and a USB port; The output end of the power supply unit is connected to the power input end of the USB port through the control unit, so as to supply power to the USB port; wherein, The control unit is used to detect the output current of the power supply unit, and cut off the power supply to the USB port when the output current is greater than a preset threshold.

2. The overcurrent protection circuit according to claim 1, It is characterized in that The control unit includes an acquisition circuit, a main control module and an execution module; The acquisition circuit is respectively connected to the power supply unit, the main control module and the USB port to detect the output current of the power supply unit; The main control module is also connected to the execution module to output a first control signal to the execution module when the output current is greater than a preset threshold; The execution module is also connected to the power supply unit to cut off the power supply to the USB port according to the first control signal.

3. The overcurrent protection circuit according to claim 2, It is characterized in that The acquisition circuit includes: a sampling resistor and a sampling module; the sampling resistor is respectively connected to the power supply unit, the USB port and the sampling module; the output end of the sampling module is connected to the main control module; The sampling module detects the output current of the sampling resistor to detect the output current of the power supply unit.

4. The overcurrent protection circuit according to claim 3, It is characterized in that The sampling module includes an operational amplifier, a first resistor, a second resistor, a third resistor and a fourth resistor; The positive phase input terminal of the operational amplifier is respectively connected to the first end of the first resistor and the second resistor; the second end of the first resistor is connected to the first end of the sampling resistor; the second end of the second resistor is grounded; the negative phase input terminal of the operational amplifier is respectively connected to the first end of the third resistor and the fourth resistor; the second end of the third resistor is connected to the second end of the sampling resistor; the second end of the fourth resistor is connected to the output terminal of the operational amplifier.

5. The overcurrent protection circuit according to claim 4, It is characterized in that The resistance values ​​of the first resistor and the third resistor are equal; the resistance values ​​of the second resistor and the fourth resistor are equal.

6. The overcurrent protection circuit according to claim 2, It is characterized in that The execution module includes a transistor; the control end of the transistor is connected to the main control module to cut off the power supply to the USB port according to the first control signal; The first end of the transistor is connected to the power supply unit; the second end of the transistor is grounded.

7. The overcurrent protection circuit according to claim 6, It is characterized in that The overcurrent protection circuit also includes a pull-up resistor; The first end of the pull-up resistor is connected to the power supply unit; the second end of the pull-up resistor is connected to the first end of the transistor.

8. The overcurrent protection circuit according to claim 2, It is characterized in that The control unit also includes a current limiting resistor; The first end of the current limiting resistor is connected to the main control module; the second end of the current limiting resistor is connected to the execution module.

9. The overcurrent protection circuit according to claim 1, It is characterized in that The overcurrent protection circuit also includes a filtering unit; The first end of the filter unit is connected to the input end of the USB port; the second end of the filter unit is connected to the ground end of the USB port.

10. The overcurrent protection circuit according to claim 9, It is characterized in that The filtering unit includes a first capacitor and a second capacitor; The first end of the first capacitor is connected to the first end of the second capacitor and the ground end of the USB port respectively; the second end of the first capacitor is connected to the second end of the second capacitor and the control unit respectively.

11. An overcurrent protection control method, It is characterized in that A control unit applied to the above-mentioned overcurrent protection circuit, wherein the overcurrent protection circuit further includes a power supply unit and a USB port, and the overcurrent protection control method includes: Obtaining an output current of the power supply unit; The output current of the power supply unit is detected, and when the output current is greater than a preset threshold, the power supply to the USB port is cut off.

12. A storage medium having a computer program stored thereon, It is characterized in that When the computer program is executed by a processor, the overcurrent protection control method as claimed in claim 11 is implemented.

13. An electronic device, It is characterized in that The invention comprises the overcurrent protection circuit according to any one of claims 1 to 10.

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