Charging protection circuit and electronic equipment

Abstract

The utility model relates to the technical field of vehicle-mounted charging, in particular to a charging protection circuit and electronic equipment. The circuit comprises a power supply port, a reverse connection protection module and an overvoltage protection module, wherein the power supply port comprises a port positive electrode and a port negative electrode; the power port is connected with an input power supply; the reverse connection protection module is used for conducting when the voltage of the positive electrode of the port is greater than the voltage of the negative electrode of the port so as to conduct a power supply loop of the input power supply, and disconnecting when the voltage of the negative electrode of the port is greater than the voltage of the positive electrode of the port so as to disconnect the power supply loop of the input power supply; and the overvoltage protection module is used for conducting when the voltage of the positive electrode of the port is greater than a preset voltage, and outputting a control signal to the reverse connection protection module when the overvoltage protection module is conducted, so that the reverse connection protection module is disconnected. According to the circuit, an anti-reverse-connection circuit structure is designed for the positive electrode and the negative electrode of a power port, an overvoltage protection circuit structure is designed on the basis of the anti-reverse-connection circuit structure, the reverse-connection protection function and the overvoltage protection function are integrated in one circuit, and the complexity and the cost of the circuit are reduced.

Description

Technical Field

[0001] This application relates to the field of vehicle charging technology, specifically to a charging protection circuit and electronic device. Background Technology

[0002] With the increasing intelligence of vehicles and the growing demand for convenient in-vehicle charging, the application of in-vehicle USB charging boxes and wireless charging devices is becoming more and more widespread. These devices, as backend electronic devices, connect directly to the vehicle's 12V power system to provide charging services for mobile devices such as smartphones and tablets. To protect in-vehicle charging equipment, related technologies typically incorporate protective circuits to prevent damage to the backend devices. Multiple relatively complex protection circuits are often used, such as comparator-based circuits to prevent reverse current surges and relay-based circuits to prevent instantaneous high voltage surges. However, using multiple independent circuits requires more electronic components, increasing material costs, circuit board design complexity, manufacturing costs, and overall integration. Utility Model Content

[0003] The embodiments of this application mainly address the technical problem of complex circuit structure and high cost of on-board charging protection circuits in related technologies.

[0004] To solve the above-mentioned technical problems, one technical solution adopted in this application is: providing a charging protection circuit, including: a power port, a reverse connection protection module, and an overvoltage protection module, wherein the power port includes a positive terminal and a negative terminal; a first terminal of the reverse connection protection module is connected to the positive terminal, a second terminal of the reverse connection protection module is connected to the negative terminal, a third terminal of the reverse connection protection module is connected to the second terminal of the overvoltage protection module, and a fourth terminal of the reverse connection protection module is grounded; a first terminal of the overvoltage protection module is connected to the positive terminal, and a third terminal of the overvoltage protection module is grounded; the power port is used to connect an input power supply; the reverse connection protection module is used to conduct when the voltage at the positive terminal is greater than the voltage at the negative terminal, so as to conduct the power supply circuit of the input power supply, and to disconnect when the voltage at the negative terminal is greater than the voltage at the positive terminal, so as to disconnect the power supply circuit of the input power supply; the overvoltage protection module is used to conduct when the voltage at the positive terminal is greater than a preset voltage, and outputs a control signal to the reverse connection protection module when conducting, so as to disconnect the reverse connection protection module.

[0005] In some embodiments, the reverse connection protection module includes a first switching unit and an anti-reverse unit. A first end of the anti-reverse unit is connected to the positive terminal of the port, and a second end of the anti-reverse unit is connected to the control terminal of the first switching unit. The first end of the first switching unit is grounded, and the second end of the first switching unit is connected to the negative terminal of the port. The anti-reverse unit is used to control the first switching unit to conduct when the voltage at the positive terminal of the port is greater than the voltage at the negative terminal of the port, so as to conduct the power supply circuit of the input power supply; and to control the first switching unit to disconnect when the voltage at the negative terminal of the port is greater than the voltage at the positive terminal of the port, so as to disconnect the power supply circuit of the input power supply.

[0006] In some embodiments, the first switching unit includes MOSFET Q1, MOSFET Q3, resistor R2, and resistor R6; the first terminal of MOSFET Q1 is connected to the first terminal of MOSFET Q3, the second terminal of MOSFET Q1 is connected to the negative terminal of the port, the control terminal of MOSFET Q1 is connected to the second terminal of the anti-reverse unit, the control terminal of MOSFET Q1 is connected to the first terminal of MOSFET Q1 through resistor R6, the second terminal of MOSFET Q3 is grounded, the control terminal of MOSFET Q3 is connected to the second terminal of the anti-reverse unit, and the control terminal of MOSFET Q3 is connected to the second terminal of MOSFET Q3 through resistor R2.

[0007] In some embodiments, the anti-reverse unit includes a diode D1 and a resistor R1; the anode of the diode D1 is connected to the positive terminal of the port through the resistor R1, and the cathode of the diode D1 is connected to the control terminal of the MOS transistor Q1.

[0008] In some embodiments, the reverse connection protection module further includes a first voltage regulator unit, a first terminal of which is connected to the control terminal of the MOSFET Q3, and a second terminal of which is connected to the second terminal of the MOSFET Q3; the first voltage regulator unit is used to limit the gate-source voltage of the MOSFET Q1 and the gate-source voltage of the MOSFET Q3.

[0009] In some embodiments, the first voltage regulator unit includes a Zener diode ZD1, the negative terminal of which is connected to the control terminal of the MOSFET Q3, and the positive terminal of which is connected to the second terminal of the MOSFET Q3.

[0010] In some embodiments, the overvoltage protection module includes a second switching unit and a second voltage regulator unit; the first terminal of the second switching unit is connected to the control terminal of the MOSFET Q3, the second terminal of the second switching unit is grounded, the control terminal of the second switching unit is connected to the second terminal of the second voltage regulator unit, and the first terminal of the second voltage regulator unit is connected to the positive terminal of the port; the second voltage regulator unit is used to conduct when the voltage at the positive terminal of the port is greater than a preset voltage and to provide a switching signal to the second switching unit; the second switching unit is used to conduct when receiving the switching signal and to control the reverse connection protection module to disconnect when conducting.

[0011] In some embodiments, the second switching unit includes a switching transistor Q2, a resistor R4, and a resistor R5; the first terminal of the switching transistor Q2 is connected to the control terminal of the MOSFET Q1, the second terminal of the switching transistor Q2 is grounded, the control terminal of the switching transistor Q2 is connected to the second terminal of the second voltage regulator unit through the resistor R4, and the control terminal of the switching transistor Q2 is connected to the second terminal of the switching transistor Q2 through the resistor R5.

[0012] In some embodiments, the second voltage regulator unit includes a Zener diode ZD2, the cathode of which is connected to the positive terminal of the port, and the anode of which is connected to the control terminal of the second switching unit.

[0013] To solve the above-mentioned technical problems, another technical solution adopted in the embodiments of this application is to provide an electronic device, including the charging protection circuit as described above.

[0014] Unlike related technologies, this application provides a charging protection circuit and electronic device. The charging protection circuit includes a power port, a reverse connection protection module, and an overvoltage protection module. The power port includes a positive terminal and a negative terminal; the power port is used to connect to an input power source. The reverse connection protection module is used to conduct when the voltage at the positive terminal is greater than the voltage at the negative terminal, thereby connecting the power supply circuit of the input power source; and to disconnect when the voltage at the negative terminal is greater than the voltage at the positive terminal, thereby disconnecting the power supply circuit of the input power source. The overvoltage protection module is used to conduct when the voltage at the positive terminal is greater than a preset voltage, and outputs a control signal to the reverse connection protection module when conducting, thereby disconnecting the reverse connection protection module. This circuit designs a reverse connection protection circuit structure for the positive and negative terminals of the power port, and on this basis, designs an overvoltage protection circuit structure, integrating reverse connection protection and overvoltage protection functions into one circuit, reducing the need for external protection components, lowering circuit complexity, and reducing circuit cost. Attached Figure Description

[0015] Figure 1 This is a schematic block diagram of a charging protection circuit provided in an embodiment of this application;

[0016] Figure 2 This is a schematic diagram of the circuit structure of a charging protection circuit provided in an embodiment of this application. Detailed Implementation

[0017] To facilitate understanding of this application, a more detailed description is provided below with reference to the accompanying drawings and specific embodiments. It should be noted that when an element is described as "connected" to another element, it can be directly connected to the other element, or one or more intermediate elements may exist between them. The terms "first," "second," etc., used in this specification are for descriptive purposes only and should not be construed as indicating or implying relative importance. Unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the application. The term "and / or" as used in this specification includes any and all combinations of one or more of the associated listed items.

[0018] The use of vehicle power supplies as input power for charging external devices is becoming increasingly common, such as using a pre-installed USB charging case or wireless charging device to charge mobile phones, tablets, and other devices. Taking a USB charging case as an example, if the vehicle or charging case's power interface markings are unclear due to wear and tear or other reasons, or if a non-professional user installs the charging case themselves, the positive and negative input terminals of the charging case may be reversed with the positive and negative terminals of the vehicle power supply. To avoid damage caused by these situations, related technologies typically incorporate protection circuits in vehicle charging systems to prevent damage to downstream devices. These often involve multiple relatively complex protection circuits, such as comparator-based protection circuits to prevent reverse current surges into downstream circuits, or relay-based protection circuits to prevent instantaneous high voltage surges into downstream circuits. However, these protection designs are usually aimed at downstream circuits, protecting the circuit components within them. Furthermore, using multiple independent circuits requires more electronic components, increasing material costs, circuit board design complexity, and manufacturing costs, resulting in lower integration levels.

[0019] To address the aforementioned issues, this application creatively proposes a novel technical solution that designs a protection circuit for the charging process when the vehicle power supply is used as the input power source. This includes a charging protection circuit for reverse connection protection and an overvoltage protection circuit structure for the charging interface and the input power source. This achieves reverse connection protection and overvoltage protection for the input power source, integrating the reverse connection and overvoltage protection functions into a single protection circuit. This reduces the need for external protection components and lowers the complexity and cost of the circuit.

[0020] The solution of this application will be explained and illustrated below with reference to specific embodiments.

[0021] Please see Figure 1 This application provides a charging protection circuit 100. As shown in the figure, the charging protection circuit includes a power port, a reverse connection protection module 13, and an overvoltage protection module 14. The power port includes a positive terminal 11 and a negative terminal 12. Specifically, the first terminal of the reverse connection protection module 13 is connected to the positive terminal 11, the second terminal of the reverse connection protection module 13 is connected to the negative terminal 12, the third terminal of the reverse connection protection module 13 is connected to the second terminal of the overvoltage protection module 14, and the fourth terminal of the reverse connection protection module 13 is grounded. The first terminal of the overvoltage protection module 14 is connected to the positive terminal 11, and the third terminal of the overvoltage protection module 14 is grounded.

[0022] The power port is used to connect to an input power source, such as a vehicle power supply. Port positive 11 and port negative 12 represent the positive and negative input terminals of the charging protection circuit 100, respectively, used to obtain power from the input power source. This embodiment uses a vehicle power supply as an example of the input power source, indicating that a power system in a vehicle powered by a car battery can charge the lithium batteries of portable / handheld devices such as mobile phones and tablets via a pre-installed vehicle charger (such as a USB charging box or wireless charging input), including power supplies of different voltage levels such as 12V, 24V, or 48V. When a vehicle power supply is used as an input power source, it is usually designed with power ports containing positive and negative terminals to power subsequent circuits. In this embodiment, these correspond to port positive 11 and port negative 12, thus there is a possibility of reversed positive and negative outputs during use.

[0023] Specifically, the reverse connection protection module 13 is used to conduct when the voltage of the positive terminal 11 of the port is greater than the voltage of the negative terminal 12 of the port, so that the input power supply can supply power to the subsequent circuit through the reverse connection protection module 13. It is also used to disconnect when the voltage of the negative terminal 12 of the port is greater than the voltage of the positive terminal 11 of the port, so that the negative terminal 12 of the port is disconnected from the subsequent circuit.

[0024] In this embodiment, port positive 11 represents a terminal for connecting to the positive output of the input power supply, such as the VCC terminal for +12V; port negative 12 represents a terminal for connecting to the negative output of the input power supply, such as the GND_EARTH terminal for connecting to the GND ground wire. Therefore, if the voltage at port positive 11 is greater than the voltage at port negative 12, it indicates that the connection between the current power port and the input power supply is correct, the reverse connection protection module 13 will conduct, and the input power supply can normally charge the subsequent circuits.

[0025] It is understood that the subsequent circuit mentioned in this application embodiment refers to a circuit that outputs electrical energy to a load using an input power source. For example, a charging circuit that supplies power to external devices such as mobile phones / tablets via a USB charging case / wireless charging input device. If the voltage at the negative terminal 12 of port 12 is greater than the voltage at the positive terminal 11 of port 11, it indicates that the current power port and the positive and negative terminals of the input power source are reversed. For example, the GND_EARTH terminal is incorrectly connected to +12V while the VCC terminal is incorrectly connected to the GND ground wire. In this case, the reverse connection protection module 13 will disconnect, cutting off the power supply loop between the input power source and the subsequent circuit to achieve reverse connection protection. This effectively prevents the performance of components in the circuit from degrading or being damaged due to excessively high voltage at the negative terminal 12 of port 12.

[0026] The overvoltage protection module 14 is used to turn on when the voltage at the positive terminal 11 of the port is greater than a preset voltage, and to control the reverse connection protection module 13 to turn off when it is on. In this embodiment, the preset voltage is the maximum value of the normal output voltage range of the input power supply, for example, 16V in this embodiment. Based on this, if the voltage at the positive terminal 11 of the port is less than (or equal to) 16V, for example, 12V, the overvoltage protection module 14 remains off, and the reverse connection protection module 13 is normally on; if the voltage at the positive terminal 11 of the port rises to more than 16V, then the overvoltage protection module 14 turns on and outputs a control signal to the reverse connection protection module 13 to make the reverse connection protection module 13 turn off, thereby cutting off the power supply loop between the input power supply and the subsequent circuit, thus realizing overvoltage protection.

[0027] The charging protection circuit provided in this application includes a power port, a reverse connection protection module, and an overvoltage protection module. The power port includes a positive terminal and a negative terminal; the power port is used to connect to an input power source. The reverse connection protection module is used to conduct when the voltage at the positive terminal is greater than the voltage at the negative terminal, thereby connecting the power supply circuit of the input power source; and to disconnect when the voltage at the negative terminal is greater than the voltage at the positive terminal, thereby disconnecting the power supply circuit of the input power source. The overvoltage protection module is used to conduct when the voltage at the positive terminal is greater than a preset voltage, and outputs a control signal to the reverse connection protection module when conducting, thereby disconnecting the reverse connection protection module. This circuit designs a reverse connection protection circuit structure for the positive and negative terminals of the power port, and an overvoltage protection circuit structure based on this, integrating reverse connection and overvoltage protection functions into one circuit. This reduces the number of protection components (such as comparators, relays, or optocouplers, etc.) required, reducing circuit complexity and cost.

[0028] In the charging protection circuit provided in the embodiments of this application, please refer to... Figure 2The reverse connection protection module 13 includes a first switch unit 131 and a reverse connection protection unit 132. The first end of the reverse connection protection unit 132 is connected to the positive terminal 11 of the port, which is shown as VCC in the figure. The second end of the reverse connection protection unit 132 is connected to the control terminal of the first switch unit 131. The first end of the first switch unit 131 is grounded to GND, and the second end of the first switch unit 131 is connected to the negative terminal 12 of the port, which is shown as GND_EARTH in the figure.

[0029] The anti-reverse unit 132 is used to control the first switching unit 131 to conduct when the voltage of the positive terminal 11 of the port is greater than the voltage of the negative terminal 12 of the port, so that the power supply circuit of the input power supply is conducted and the input power supply normally supplies power to the subsequent circuit, such as charging the connected device; and it is used to control the first switching unit 131 to disconnect when the voltage of the negative terminal 12 of the port is greater than the voltage of the positive terminal 11 of the port, so that the power supply circuit of the input power supply is disconnected, protecting the safety of the input power supply and the charging protection circuit itself.

[0030] Specifically, Figure 2 An example circuit structure for a charging protection circuit is shown. For example... Figure 2 As shown, the first switching unit 131 includes MOSFET Q1, MOSFET Q3, resistor R2 and resistor R6; the anti-reverse unit 132 includes diode D1 and resistor R1.

[0031] In this configuration, the first terminal Q1_S of MOSFET Q1 is connected to the first terminal Q3_S of MOSFET Q3, the second terminal Q1_D of MOSFET Q1 is connected to the negative terminal 12 of port 12, and the control terminal Q1_G of MOSFET Q1 is connected to the second terminal of the anti-reverse unit 132, which is also the cathode of diode D1. The control terminal Q1_G of MOSFET Q1 is connected to the first terminal Q1_S of MOSFET Q1 through resistor R6. The second terminal Q3_D of MOSFET Q3 is grounded, which is GND in the figure. The control terminal Q3_G of MOSFET Q3 is connected to the second terminal of the anti-reverse unit 132, which is also the cathode of diode D1. The control terminal Q3_G of MOSFET Q3 is connected to the second terminal Q3_D of MOSFET Q3 through resistor R2. The anode of diode D1 is connected to the positive terminal 11 of port 11 through resistor R1.

[0032] like Figure 2As shown, when the positive terminal VCC of the input power supply is connected to the positive terminal (e.g., +12V) and the negative terminal GND_EARTH is connected to the negative terminal (e.g., GND ground), the input power supply voltage forms a loop based on diode D1. The power supply voltage, after being divided by resistors R1, R2, and R6, provides the turn-on voltage for MOSFETs Q1 and Q3. MOSFETs Q1 and Q3 conduct, and the input power supply powers the connected subsequent circuits, such as charging a mobile device connected via a USB charging case. If a reverse connection occurs, causing the positive terminal VCC to be connected to GND ground and the negative terminal GND_EARTH to the positive terminal +12V of the power supply output, then due to the limitation of diode D1, MOSFETs Q1 and Q3 will not conduct. The power supply loop of the input power supply is in an open circuit state, thus protecting the input power supply and the charging protection circuit itself. Based on this, the charging protection circuit provided in this solution can also precisely control the gate-source voltage of MOSFETs Q1 and Q3 by adjusting the resistance values ​​of resistors R1, R6 and R2, combined with the voltage value of the input power supply, thereby controlling their conduction and cutoff.

[0033] In some embodiments, the reverse connection protection module 13 further includes a first voltage regulator unit 133. The first terminal of the first voltage regulator unit is connected to the control terminal of the MOSFET Q1, and the second terminal of the first voltage regulator unit 133 is connected to the first terminal of the MOSFET Q1. The first voltage regulator unit 133 can limit the gate-source voltage of the MOSFET Q1 and the MOSFET Q3. This solution limits the gate-source voltage of the MOSFET Q1 by setting the first voltage regulator unit 133, thereby protecting the MOSFET Q1 from damage due to excessive voltage. This is particularly important when transient overvoltage or voltage fluctuations occur in the circuit, indirectly improving the reliability and lifespan of the MOSFET Q1.

[0034] like Figure 2 As shown, the first voltage regulator unit 133 may include a Zener diode ZD1. The cathode of the Zener diode ZD1 is connected to the control terminal Q3_G of the MOSFET Q3, and the anode of the Zener diode ZD1 is connected to the second terminal Q3_D of the MOSFET Q3. This scheme uses the Zener diode ZD1 to limit the gate-source voltage V1 of the MOSFET Q1. gs and the gate-source voltage V2 of MOSFET Q3 gs If the gate voltage rises above the Zener diode ZD1, ZD1 will conduct and clamp the gate voltage near the Zener value, preventing damage to MOSFET Q1 or Q3 due to excessive gate voltage. This solution achieves voltage limiting without complex control circuitry or an additional power supply, simplifying the circuit design and limiting costs.

[0035] In some embodiments, the overvoltage protection module 14 includes a second switching unit 141 and a second voltage regulator unit 142. The first terminal of the second switching unit 141 is connected to the control terminal of the MOSFET Q3, and the second terminal of the second switching unit 141 is grounded. The control terminal of the second switching unit 141 is connected to the second terminal of the second voltage regulator unit 142, and the first terminal of the second voltage regulator unit 142 is connected to the positive terminal 11 of the port. The second voltage regulator unit 142 conducts when the voltage at the positive terminal 11 of the port exceeds a preset voltage and provides a switching signal to the second switching unit 141. The second switching unit 141 conducts upon receiving the switching signal and outputs a control signal to the reverse connection protection module 13 to disconnect the reverse connection protection module 13. Specifically, it outputs a low-level signal (control signal) to the control terminals of the MOSFETs Q1 and Q3 to disconnect the MOSFETs Q1 and Q3, thereby cutting off the power supply loop from the input power supply to the subsequent circuits and preventing damage to the charging protection circuit and subsequent circuits due to overvoltage.

[0036] Please combine Figure 2 , Figure 2 An example circuit structure of the overvoltage protection module 14 is shown. As shown, the second switching unit 141 includes a switching transistor Q2, resistors R4 and R5; the second voltage regulator unit 142 includes a Zener diode ZD2. The first terminal Q2_3 of the switching transistor Q2 is connected to the control terminal Q3_G of the MOSFET Q3, and the second terminal Q2_2 of the switching transistor Q2 is grounded. The control terminal Q2_1 of the switching transistor Q2 is connected to the second terminal of the second voltage regulator unit 142, i.e., the anode of the Zener diode ZD2, through resistor R4; the control terminal Q2_1 of the switching transistor Q2 is connected to the second terminal Q2_2 of the switching transistor Q2 through resistor R5. The cathode of the Zener diode ZD2 is connected to the positive terminal VCC, and the anode of the Zener diode ZD2 is connected to the control terminal of the switching unit 141, i.e., connected to the control terminal Q2_1 of the switching transistor Q2 through resistor R4.

[0037] In this circuit, the switching transistor Q2 can be a bipolar transistor. The preset voltage is the Zener diode ZD2's voltage regulation value. A suitable Zener diode can be selected based on the input power supply voltage under normal operating conditions to build this circuit. For example, assuming the normal input power supply voltage is 12V, a Zener diode ZD2 with a voltage regulation value slightly higher than 12V can be selected, such as a 16V Zener diode ZD2, with a corresponding preset voltage of 16V. Based on this, when the voltage at the positive terminal VCC exceeds the preset voltage of 16V, the Zener diode ZD2 conducts, providing a corresponding base voltage to the switching transistor Q2 through resistor R4 as a switching signal, controlling the switching transistor Q2 to conduct. Simultaneously, it limits the base voltage of the switching transistor Q2 to approximately 16V, preventing excessive voltage from damaging Q2. After the switching transistor Q2 is turned on, it pulls down the gate voltage of MOSFETs Q1 and Q3, causing MOSFETs Q1 and Q3 to turn off, thereby cutting off the power supply loop for the subsequent circuit and preventing overvoltage from damaging the charging protection circuit and the subsequent circuit.

[0038] In some embodiments, such as Figure 2 As shown, the switching unit 141 also includes a current-limiting resistor R3. The first end of the current-limiting resistor R3 is connected to the control terminal Q2_1 of the switching transistor Q2. The second end of the current-limiting resistor R3 is grounded through a resistor R5. The second end of the current-limiting resistor R3 is connected to the second terminal of the second voltage regulator unit 142, which is the anode of the Zener diode ZD2, through a resistor R4. This resistor R3 can limit the base current of the switching transistor Q2, preventing excessive current from damaging the component.

[0039] The charging protection circuit provided in this application has a simple circuit structure, requiring only two MOSFETs and one transistor as key components. Combined with two Zener diodes and several resistors, it can achieve reverse connection protection and overvoltage protection functions. It does not require comparators or other operational amplifiers or a separate power supply, thus reducing circuit complexity and cost.

[0040] This application provides an electronic device that includes the aforementioned charging protection circuit. The electronic device possesses the corresponding functional modules and beneficial effects of the charging protection circuit. Technical details not described in detail in this embodiment can be found in the charging protection circuit provided in this invention.

[0041] It should be noted that while preferred embodiments of this application are provided in the specification and accompanying drawings, this application can be implemented in many different forms and is not limited to the embodiments described herein. These embodiments are not intended to impose additional limitations on the content of this application; their purpose is to provide a more thorough and comprehensive understanding of the disclosure of this application. Furthermore, the above-described technical features can be combined with each other to form various embodiments not listed above, all of which are considered to be within the scope of this application's specification. Moreover, those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims.

Claims

1. A charging protection circuit, characterized in that, include: The power port includes a reverse connection protection module and an overvoltage protection module, wherein the power port includes a positive terminal and a negative terminal; The first terminal of the reverse connection protection module is connected to the positive terminal of the port, the second terminal of the reverse connection protection module is connected to the negative terminal of the port, the third terminal of the reverse connection protection module is connected to the second terminal of the overvoltage protection module, and the fourth terminal of the reverse connection protection module is grounded; the first terminal of the overvoltage protection module is connected to the positive terminal of the port, and the third terminal of the overvoltage protection module is grounded. The power port is used to connect to the input power supply; The reverse connection protection module is configured to conduct when the voltage at the positive terminal of the port is greater than the voltage at the negative terminal of the port, so as to conduct the power supply circuit of the input power supply; and to disconnect when the voltage at the negative terminal of the port is greater than the voltage at the positive terminal of the port, so as to disconnect the power supply circuit of the input power supply. The overvoltage protection module is used to conduct when the voltage at the positive terminal of the port is greater than a preset voltage, and outputs a control signal to the reverse connection protection module when it is conducted, so as to disconnect the reverse connection protection module.

2. The charging protection circuit according to claim 1, characterized in that, The reverse connection protection module includes a first switch unit and a reverse protection unit. The first end of the reverse protection unit is connected to the positive terminal of the port, and the second end of the reverse protection unit is connected to the control terminal of the first switch unit. The first end of the first switch unit is grounded, and the second end of the first switch unit is connected to the negative terminal of the port. The anti-reverse unit is used to control the first switching unit to conduct when the voltage at the positive terminal of the port is greater than the voltage at the negative terminal of the port, so as to conduct the power supply circuit of the input power supply; and to control the first switching unit to disconnect when the voltage at the negative terminal of the port is greater than the voltage at the positive terminal of the port, so as to disconnect the power supply circuit of the input power supply.

3. The charging protection circuit according to claim 2, characterized in that, The first switching unit includes MOSFET Q1, MOSFET Q3, resistor R2, and resistor R6; The first terminal of MOSFET Q1 is connected to the first terminal of MOSFET Q3, the second terminal of MOSFET Q1 is connected to the negative terminal of the port, the control terminal of MOSFET Q1 is connected to the second terminal of the anti-reverse unit, the control terminal of MOSFET Q1 is connected to the first terminal of MOSFET Q1 through resistor R6, the second terminal of MOSFET Q3 is grounded, the control terminal of MOSFET Q3 is connected to the second terminal of the anti-reverse unit, and the control terminal of MOSFET Q3 is connected to the second terminal of MOSFET Q3 through resistor R2.

4. The charging protection circuit according to claim 3, characterized in that, The anti-reverse unit includes a diode D1 and a resistor R1; The anode of diode D1 is connected to the positive terminal of the port through resistor R1, and the cathode of diode D1 is connected to the control terminal of MOS transistor Q1.

5. The charging protection circuit according to claim 3, characterized in that, The reverse connection protection module further includes a first voltage regulator unit, the first end of which is connected to the control terminal of the MOSFET Q3, and the second end of which is connected to the second terminal of the MOSFET Q3. The first voltage regulator unit is used to limit the gate-source voltage of the MOSFET Q1 and the gate-source voltage of the MOSFET Q3.

6. The charging protection circuit according to claim 5, characterized in that, The first voltage regulator unit includes a Zener diode ZD1, the negative terminal of which is connected to the control terminal of the MOSFET Q3, and the positive terminal of which is connected to the second terminal of the MOSFET Q3.

7. The charging protection circuit according to claim 3, characterized in that, The overvoltage protection module includes a second switching unit and a second voltage regulating unit; The first terminal of the second switching unit is connected to the control terminal of the MOSFET Q3, the second terminal of the second switching unit is grounded, the control terminal of the second switching unit is connected to the second terminal of the second voltage regulator unit, and the first terminal of the second voltage regulator unit is connected to the positive terminal of the port. The second voltage regulator unit is used to turn on when the voltage at the positive terminal of the port is greater than a preset voltage, and to provide a switching signal to the second switching unit; The second switching unit is used to turn on when receiving the switching signal, and to control the reverse connection protection module to turn off when it is turned on.

8. The charging protection circuit according to claim 7, characterized in that, The second switching unit includes a switching transistor Q2, a resistor R4, and a resistor R5; The first terminal of the switching transistor Q2 is connected to the control terminal of the MOSFET Q1, the second terminal of the switching transistor Q2 is grounded, the control terminal of the switching transistor Q2 is connected to the second terminal of the second voltage regulator unit through the resistor R4, and the control terminal of the switching transistor Q2 is connected to the second terminal of the switching transistor Q2 through the resistor R5.

9. The charging protection circuit according to claim 8, characterized in that, The second voltage regulator unit includes a Zener diode ZD2, the cathode of which is connected to the positive terminal of the port, and the anode of which is connected to the control terminal of the second switching unit.

10. An electronic device, characterized in that, Includes the charging protection circuit as described in any one of claims 1-9.

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