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CN-224204787-U - Charging protection circuit and electronic equipment

CN224204787UCN 224204787 UCN224204787 UCN 224204787UCN-224204787-U

Abstract

The application relates to the technical field of vehicle-mounted charging, in particular to a charging protection circuit and electronic equipment. The circuit comprises a power port, a reverse connection protection module and an overvoltage protection module, wherein the power 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 port positive electrode is larger than the voltage of the port negative electrode so as to conduct a power supply loop of the input power supply, and disconnecting when the voltage of the port negative electrode is larger than the voltage of the port positive electrode 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 port positive electrode is larger than a preset voltage and outputting a control signal to the reverse connection protection module when the voltage of the port positive electrode is larger than the preset voltage so as to disconnect the reverse connection protection module. The circuit is designed to be a circuit structure for preventing reverse connection aiming at the positive pole and the negative pole of the power port, and an overvoltage protection circuit structure is designed on the basis, so that the reverse connection protection and the overvoltage protection functions are integrated into one circuit, and the complexity and the circuit cost of the circuit are reduced.

Inventors

  • LUO HUI

Assignees

  • 卓能汽车技术(深圳)有限公司

Dates

Publication Date
20260505
Application Date
20250515

Claims (10)

  1. 1. The charging protection circuit is characterized by comprising a power port, a reverse connection protection module and an overvoltage protection module, wherein the power port comprises a port anode and a port cathode; The first end of the reverse connection protection module is connected with the port positive electrode, the second end of the reverse connection protection module is connected with the port negative electrode, the third end of the reverse connection protection module is connected with the second end of the overvoltage protection module, and the fourth end of the reverse connection protection module is grounded; The power port is used for connecting an input power supply; The reverse connection protection module is used for being conducted when the voltage of the positive electrode of the port is larger than the voltage of the negative electrode of the port so as to conduct a power supply loop of the input power supply, and is used for being disconnected when the voltage of the negative electrode of the port is larger than the voltage of the positive electrode of the port so as to disconnect the power supply loop of the input power supply; The overvoltage protection module is used for being conducted when the voltage of the positive electrode of the port is larger than a preset voltage, and outputting a control signal to the reverse connection protection module when the voltage of the positive electrode of the port is conducted, so that the reverse connection protection module is disconnected.
  2. 2. The charge protection circuit of claim 1, wherein the reverse connection protection module comprises a first switch unit and a reverse connection prevention unit, a first end of the reverse connection prevention unit is connected with the positive electrode of the port, a second end of the reverse connection prevention unit is connected with a control end of the first switch unit, a first end of the first switch unit is grounded, and a second end of the first switch unit is connected with the negative electrode of the port; the anti-reflection unit is used for controlling the first switch unit to be conducted when the voltage of the positive electrode of the port is larger than the voltage of the negative electrode of the port so as to conduct a power supply loop of the input power supply, and controlling the first switch unit to be disconnected when the voltage of the negative electrode of the port is larger than the voltage of the positive electrode of the port so as to disconnect the power supply loop of the input power supply.
  3. 3. The charge protection circuit of claim 2, wherein the first switching unit comprises a MOS transistor Q1, a MOS transistor Q3, a resistor R2, and a resistor R6; The first end of MOS pipe Q1 is connected the first end of MOS pipe Q3, the second end of MOS pipe Q1 is connected the port negative pole, MOS pipe Q1's control end is connected the second end of preventing the anti-unit, MOS pipe Q1's control end is passed through resistance R6 is connected to MOS pipe Q1's first end, MOS pipe Q3's second ground connection, MOS pipe Q3's control end is connected prevent the second end of anti-unit, MOS pipe Q3's control end is passed through resistance R2 is connected to MOS pipe Q3's second end.
  4. 4. A charge protection circuit according to claim 3, wherein the anti-reflection unit includes a diode D1 and a resistor R1; The anode of the diode D1 is connected to the positive electrode of the port through the resistor R1, and the cathode of the diode D1 is connected with the control end of the MOS tube Q1.
  5. 5. The charge protection circuit according to claim 3, wherein the reverse connection protection module further comprises a first voltage stabilizing unit, a first end of the first voltage stabilizing unit is connected to the control end of the MOS transistor Q3, and a second end of the first voltage stabilizing unit is connected to the second end of the MOS transistor Q3; The first voltage stabilizing unit is used for limiting the gate-source voltage of the MOS transistor Q1 and the gate-source voltage of the MOS transistor Q3.
  6. 6. The charge protection circuit of claim 5, wherein the first voltage stabilizing unit comprises a voltage stabilizing diode ZD1, a cathode of the voltage stabilizing diode ZD1 is connected with a control end of the MOS transistor Q3, and an anode of the voltage stabilizing diode ZD1 is connected with a second end of the MOS transistor Q3.
  7. 7. A charge protection circuit according to claim 3, wherein the overvoltage protection module comprises a second switching unit and a second voltage stabilizing unit; The first end of the second switch unit is connected with the control end of the MOS tube Q3, the second end of the second switch unit is grounded, the control end of the second switch unit is connected with the second end of the second voltage stabilizing unit, and the first end of the second voltage stabilizing unit is connected with the positive electrode of the port; The second voltage stabilizing unit is used for being conducted when the voltage of the positive electrode of the port is larger than a preset voltage, and providing a switching signal to the second switching unit; The second switch unit is used for being conducted when the switch signal is received, and controlling the reverse connection protection module to be disconnected when the second switch unit is conducted.
  8. 8. The charge protection circuit of claim 7, wherein the second switching unit comprises a switching tube Q2, a resistor R4, and a resistor R5; The first end of the switching tube Q2 is connected with the control end of the MOS tube Q1, the second end of the switching tube Q2 is grounded, the control end of the switching tube Q2 is connected to the second end of the second voltage stabilizing unit through the resistor R4, and the control end of the switching tube Q2 is connected to the second end of the switching tube Q2 through the resistor R5.
  9. 9. The charge protection circuit according to claim 8, wherein the second voltage stabilizing unit includes a voltage stabilizing diode ZD2, a cathode of the voltage stabilizing diode ZD2 is connected to the port positive electrode, and an anode of the voltage stabilizing diode ZD2 is connected to the control terminal of the second switching unit.
  10. 10. An electronic device comprising a charge protection circuit as claimed in any one of claims 1-9.

Description

Charging protection circuit and electronic equipment Technical Field The application relates to the technical field of vehicle-mounted charging, in particular to a charging protection circuit and electronic equipment. Background With the increasing demands of vehicle intellectualization and users for vehicle-mounted charging convenience, applications of the vehicle-mounted USB charging box and the wireless charging device are becoming wider. The devices are used as back-end electronic devices and are directly connected to a vehicle-mounted 12V power supply system to provide charging service for mobile terminals such as mobile phones and tablet computers. In order to protect the on-vehicle charging device, the related art generally designs a protection circuit for the on-vehicle charging to prevent damage of the back end device, and generally provides a plurality of protection circuits having relatively complicated structures, such as a protection circuit for preventing reverse current surge based on a comparator, a protection circuit for preventing instantaneous large voltage surge based on a relay, and the like. However, the use of multiple independent circuits means that more electronic components are needed, which not only increases the material cost, but also increases the design complexity and the manufacturing cost of the circuit board, and the degree of integration is low. Disclosure of utility model The implementation mode of the application mainly solves the technical problems of complex circuit structure and high cost of the vehicle-mounted charging protection circuit in the related technology. In order to solve the technical problems, the technical scheme adopted by the embodiment of the application is that the charging protection circuit comprises a power port, a reverse connection protection module and an overvoltage protection module, wherein the power port comprises a port positive electrode and a port negative electrode, a first end of the reverse connection protection module is connected with the port positive electrode, a second end of the reverse connection protection module is connected with the port negative electrode, a third end of the reverse connection protection module is connected with the second end of the overvoltage protection module, a fourth end of the reverse connection protection module is grounded, a first end of the overvoltage protection module is connected with the port positive electrode, a third end of the overvoltage protection module is grounded, the power port is used for being connected with an input power supply, the reverse connection protection module is used for being conducted when the voltage of the port positive electrode is larger than the voltage of the port negative electrode, so that a power supply loop of the input power supply is conducted when the voltage of the port negative electrode is larger than the voltage of the port positive electrode, so that a loop of the input power supply is disconnected, and the reverse connection protection module is conducted when the voltage of the port positive electrode is larger than the preset voltage, and the reverse connection protection module is conducted when the overvoltage protection module is used for controlling the reverse connection protection module to be conducted. In some embodiments, the reverse connection protection module comprises a first switch unit and a reverse connection protection unit, wherein a first end of the reverse connection protection unit is connected with the positive electrode of the port, a second end of the reverse connection protection unit is connected with a control end of the first switch unit, a first end of the first switch unit is grounded, a second end of the first switch unit is connected with the negative electrode of the port, the reverse connection protection unit is used for controlling the first switch unit to be conducted when the voltage of the positive electrode of the port is larger than the voltage of the negative electrode of the port so as to conduct a power supply loop of the input power supply, and controlling the first switch unit to be disconnected when the voltage of the negative electrode of the port is larger than the voltage of the positive electrode of the port so as to disconnect the power supply loop of the input power supply. In some embodiments, the first switch unit comprises a MOS tube Q1, a MOS tube Q3, a resistor R2 and a resistor R6, wherein the first end of the MOS tube Q1 is connected with the first end of the MOS tube Q3, the second end of the MOS tube Q1 is connected with the port negative electrode, the control end of the MOS tube Q1 is connected with the second end of the anti-reflection unit, the control end of the MOS tube Q1 is connected to the first end of the MOS tube Q1 through the resistor R6, the second end of the MOS tube Q3 is grounded, the control end of the MOS tube Q3 is connected with the second end of the anti-reflectio