CN116054309B

CN116054309B - Charging circuit, electronic device, charging system and reverse charging method

Info

Publication number: CN116054309B
Application number: CN202210921945.1A
Authority: CN
Inventors: 秦恒亮
Original assignee: Honor Device Co Ltd
Current assignee: Honor Device Co Ltd
Priority date: 2022-08-02
Filing date: 2022-08-02
Publication date: 2023-12-19
Anticipated expiration: 2042-08-02
Also published as: WO2024027208A9; WO2024027208A1; CN116054309A

Abstract

The embodiment of the application provides a charging circuit, electronic equipment, a charging system and a reverse charging method, relates to the technical field of circuits, and aims to realize that the electronic equipment supplies power to any external equipment in a starting state, and is not limited to a PD protocol. The charging circuit comprises a control module, a charging protocol module, a first power module, a second power module, a first switch module, a wired external interface and a pull-up module; the wired external interface comprises a first pin and a second pin; the pull-up module provides a first level signal to the first node; when the first node is changed from the first level signal to the second level signal, the second power module supplies power for the control module and the charging protocol module; when the second power module supplies power to the charging protocol module, the charging protocol module identifies whether a charging cable is inserted into the wired external interface, and when the charging cable is inserted, the second power module controls the first switch module to be conducted so that the first power module supplies power to external equipment to be charged through the charging cable.

Description

Charging circuit, electronic device, charging system and reverse charging method

Technical Field

The application relates to the technical field of circuits, in particular to a charging circuit, electronic equipment, a charging system and a reverse charging method.

Background

With the development and progress of society, electronic devices (such as mobile phones) have become an integral part of life. Under the condition that an external power supply does not exist, if electronic equipment such as a mobile phone needs to be charged urgently to keep cruising, a user can use other mobile portable equipment (such as the mobile phone, a tablet computer, a notebook computer and the like) to supply power to the electronic equipment.

However, these mobile portable devices can only charge the external electronic device in the on state (which may be referred to as reverse charging), but cannot charge the external electronic device in the off state, which is not beneficial to user experience.

Disclosure of Invention

In order to solve the technical problems, the application provides a charging circuit, an electronic device and a reverse charging method. The power supply of the electronic equipment to any equipment to be charged in a shutdown scene can be realized.

In a first aspect, an embodiment of the present application provides a charging circuit, applied to an electronic device, including: the device comprises a control module, a charging protocol module, a first power module, a second power module, a first switch module, a wired external interface and a pull-up module; the wired external interface comprises a first pin and a second pin; the control module is respectively and electrically connected with the first power supply module, the second power supply module and the charging protocol module, the charging protocol module is respectively and electrically connected with the second power supply module, the control end of the first switch module and the first pin, the first end of the first switch module is electrically connected with the first power supply module, the second end of the first switch module is electrically connected with the second pin, and the pull-up module and the first pin are coupled with the first node; the pull-up module is used for providing a first level signal for the first node; when the first node is changed from the first level signal to the second level signal, the second power module is used for supplying power to the control module and the charging protocol module; when the second power module supplies power to the charging protocol module, the charging protocol module is used for identifying whether a charging cable is inserted into the wired external interface, and when the charging protocol module identifies that the charging cable is inserted into the wired external interface, the charging protocol module is also used for controlling the first switch module to be conducted so that the first power module supplies power to an external device to be charged (also called external device to be charged) through the second pin and the charging cable when the electronic device is in a power-off state.

The first pin of the wired external connection interface is provided with the pull-up module, so that the level of the first pin of the wired external connection interface changes when the first pin is connected with the charging cable and when the first pin is not connected with the charging cable, the second power module supplies power to the second power module and the charging protocol module based on the level change, and then the charging protocol module recognizes the protocol, the first switch module is opened, and the control module controls the first power module to supply power to the outside, namely, the electronic equipment such as a notebook computer, a tablet computer and a desktop computer is powered as main equipment under a shutdown scene, and the power is supplied to any external equipment without being limited to a PD protocol.

Illustratively, the control module may be an embedded Controller (EC embedded Controller).

By way of example, the charging protocol module may be a USB-PD (Power Delivery) protocol module, such as a USB-PD protocol IC.

The wired external interface may be, for example, a USB Type-C interface. The first pin may be a CC (Configuation Channel, configuration channel) pin. The second pin may be a VBUS pin.

The second power module is, for example, a buck circuit, and is configured to output a fixed voltage, for example, 3.3V, and to fully supply power to the control module and the charging protocol module when the electronic device (such as a notebook computer) is in a power-off state.

The first Switch module may be, for example, a Load Switch (LS) chip.

According to a first aspect, in the charging circuit, the pull-up module includes a pull-up resistor, and a first end of the pull-up resistor is configured to receive a first control signal, so that a signal of the first node is a first level signal; the second end of the pull-up resistor and the first pin are coupled to the first node. Simple structure and low cost.

The third power module may be configured to provide power to a portion of the ports of the control module before the second power module provides power to the control module and the charging protocol module. The control module controls the third power module to stop supplying power to the second power module when controlling the second power module to supply power to the third power module, and controls the second power module to stop supplying power to the third power module when controlling the third power module to supply power to the third power module, and the control module controls the third power module to not supply power or stop supplying power through sending a switching signal, wherein the first control signal is a switching signal for example.

According to the first aspect, or any implementation manner of the first aspect, the pull-up module further includes a diode, an anode of the diode is used for receiving the first control signal, and a cathode of the diode is electrically connected to the first end of the pull-up resistor. The signal of the first end of the pull-up resistor can be prevented from being influenced by the signal of the first node, and the stability of the circuit is improved.

In accordance with the first aspect, or any implementation manner of the first aspect, in the charging circuit, a resistance value of the pull-up resistor is greater than 5.1 kiloohms. The setting like this can avoid the resistance of pull-up resistance too little, when OTG line inserts the wired external interface, the effect of pull-down can't be reached to the pull-down resistance in the OTG line.

According to a first aspect, or any implementation manner of the first aspect, in the charging circuit, the control module includes a first port, and the first port, the first pin, and the pull-up module are coupled to a first node; the control module is used for collecting signals of the first node, and when the first node is changed from the first level signal to the second level signal, the control module is also used for sending a first switch signal to the second power module so that the second power module supplies power for the control module and the charging protocol module. The control module is used for identifying the change of the first node level, and when the change is identified, the second power module is enabled to supply power to the control module and the charging protocol module, so that the charging protocol module is enabled to identify the protocol, the first switch module is opened, the control module is used for controlling the first power module to supply power to the outside, namely, the electronic equipment such as a notebook computer, a tablet computer and a desktop computer is used as main equipment in a shutdown scene, and the power is supplied to any external equipment, so that the PD protocol of a TypeC port is not limited.

According to the first aspect, or any implementation manner of the first aspect, the charging circuit further includes a second switch module, a first end of the second switch module is electrically connected to the first node, a second end of the second switch module is electrically connected to the first port, and a control end of the second switch module is configured to receive a second control signal; the second control signal is used for controlling the second switch module to be turned on when the signal of the first node is a first level signal, and controlling the second switch module to be turned off when the signal of the first node is changed from the first level signal to a second level signal. By the arrangement, when the charging protocol module carries out protocol identification, the signal of the first port of the control module can be prevented from affecting the signal of the first node, and further the protocol identification of the charging protocol module is prevented.

In the charging circuit according to the first aspect, or any implementation manner of the first aspect, when the pull-up module includes a pull-up resistor, the second control signal is the first control signal. The circuit structure is simplified, and the corresponding structure is not required to be arranged separately to provide the first control signal.

According to a first aspect, or any implementation manner of the first aspect, in the charging circuit, the second switch module includes a structure that can implement a switching function, such as a mosfet.

According to a first aspect, or any implementation manner of the first aspect, the charging circuit further comprises a logic non-circuit, an input terminal of the logic non-circuit being coupled to the first node; the output end of the logic NOT circuit is electrically connected with the second power supply module; when the first node is changed from the first level signal to the second level signal, the logic NOT circuit is used for controlling the second power supply module to supply power for the control module and the charging protocol module. The change of the first node level is identified through the logic NOT circuit, and when the change is identified, the second power module is enabled to supply power to the control module and the charging protocol module, so that the charging protocol module is enabled to identify the protocol, the first switch module is turned on, and the control module is enabled to control the first power module to supply power to the outside, namely, the electronic equipment such as a notebook computer, a tablet computer and a desktop computer is used as main equipment in a shutdown scene, and any external equipment is powered, and the PD protocol of the TypeC port is not limited.

According to the first aspect, or any implementation manner of the first aspect, the charging circuit further includes a third power module electrically connected to the control module; the control module is used for controlling the third power module to stop supplying power to the control module when the second power module is controlled to supply power to the control module and the charging protocol module, and stopping supplying power to the control module and the charging protocol module by the second power module when the third power module is controlled to supply power to the control module. In order to ensure that certain ports can work with low power consumption when the control module is in a shutdown state.

The third power module may include a low dropout linear regulator.

According to the first aspect, or any implementation manner of the first aspect, in the charging circuit, a first end of a pull-up resistor is electrically connected with the control module and the third power module; the first control signal received by the first end of the pull-up resistor is a second switching signal sent by the control module to the third power module, wherein the second switching signal is used for controlling the third power module to supply power to the control module or stopping supplying power to the control module. The signal of the control end of the second switch module, the signal of the first end of the pull-up resistor and the switch signal sent to the third power module by the control module are the same signal, so that the circuit structure is simplified, the signal can be provided through the control module, and the signal of the control end of the second switch module and the signal of the first end of the pull-up resistor are not required to be provided by the corresponding structures independently.

In a second aspect, embodiments of the present application provide an electronic device. The electronic device includes: the charging circuit according to the first aspect and any implementation manner of the first aspect.

Wherein, this electronic equipment can also include: one or more processors; a memory; and one or more computer programs, wherein the one or more computer programs are stored on the memory, which when executed by the one or more processors, cause the electronic device to perform corresponding functions.

According to the second aspect, the electronic device may be a notebook computer or a smart phone.

Any implementation manner of the second aspect and the second aspect corresponds to any implementation manner of the first aspect and the first aspect, respectively. The technical effects corresponding to the second aspect and any implementation manner of the second aspect may be referred to the technical effects corresponding to the first aspect and any implementation manner of the first aspect, which are not described herein.

In a third aspect, an embodiment of the present application provides a reverse charging method, which is applied to the electronic device corresponding to any implementation manner of the second aspect and the second aspect. The reverse charging method comprises the following steps: when the first node is detected to be changed from the first level signal to the second level signal, the electronic equipment supplies power for the control module and the charging protocol module; when the charging cable is identified to be inserted into the wired external interface, the electronic equipment supplies power to the external equipment to be charged through the second pin and the charging cable in the shutdown state.

Any implementation manner of the third aspect and any implementation manner of the third aspect corresponds to any implementation manner of the second aspect and the second aspect, respectively. The technical effects corresponding to the third aspect and any implementation manner of the third aspect may be referred to the technical effects corresponding to the second aspect and any implementation manner of the second aspect, which are not described herein.

In a fourth aspect, embodiments of the present application provide a computer-readable storage medium. The computer readable storage medium comprises a computer program which, when run on an electronic device, causes the electronic device to perform the reverse charging method of any one of the third aspect and the third aspect.

Any implementation manner of the fourth aspect and any implementation manner of the fourth aspect corresponds to any implementation manner of the third aspect and any implementation manner of the third aspect, respectively. Technical effects corresponding to any implementation manner of the fourth aspect may be referred to the technical effects corresponding to any implementation manner of the third aspect, and are not described herein.

In a fifth aspect, embodiments of the present application provide a computer program product comprising a computer program which, when run, causes a computer to perform the reverse charging method as in any of the third or fourth aspects.

Any implementation manner of the fifth aspect and any implementation manner of the fifth aspect corresponds to any implementation manner of the third aspect and any implementation manner of the third aspect, respectively. Technical effects corresponding to any implementation manner of the fifth aspect may be referred to the technical effects corresponding to any implementation manner of the third aspect, and are not described herein.

In a sixth aspect, the present application provides a chip comprising processing circuitry, a transceiver pin. Wherein the transceiver pin and the processing circuit communicate with each other through an internal connection path, the processing circuit performing the reverse charging method as in any one of the third aspect or the third aspect to control the receiving pin to receive a signal, to control the transmitting pin to transmit a signal.

Any implementation manner of the sixth aspect and any implementation manner of the sixth aspect correspond to any implementation manner of the third aspect and any implementation manner of the third aspect, respectively. Technical effects corresponding to any implementation manner of the sixth aspect may be referred to the technical effects corresponding to any implementation manner of the third aspect, and are not described herein.

In a seventh aspect, the present application also provides a reverse charging system. The reverse charging system comprises an electronic device and an external device, wherein the electronic device is connected with the external device through a wired external interface, and the electronic device is used for carrying out reverse charging on the external device in a shutdown state. The electronic device is an electronic device corresponding to any implementation manner of the second aspect and the second aspect, and when the reverse charging method according to the third aspect or any implementation manner of the third aspect is executed, reverse charging is performed to the external device.

The electronic device is a notebook computer, and may also be a smart phone.

According to a seventh aspect, the reverse charging system further includes an OTG line, and when one end of the OTG line is electrically connected to the electronic device and the other end is electrically connected to the external device, the electronic device is configured to reverse charge the external device through the OTG line in the shutdown state. The level of the first node is changed through the OTG line.

Any implementation manner of the seventh aspect and any implementation manner of the seventh aspect corresponds to any implementation manner of the third aspect and any implementation manner of the third aspect, respectively. Technical effects corresponding to any implementation manner of the seventh aspect may be referred to technical effects corresponding to any implementation manner of the third aspect and the third aspect, and are not described herein.

Drawings

FIG. 1 is a schematic illustration of an exemplary application scenario;

FIG. 2 is a schematic diagram of a pin of the USB Type-C interface;

fig. 3 is a schematic structural diagram of a charging circuit according to an embodiment of the present application;

fig. 4 is a schematic structural diagram of another charging circuit according to an embodiment of the present disclosure;

fig. 5 is a schematic structural diagram of an OTG line according to an embodiment of the present application;

FIG. 6 is a schematic diagram illustrating an exemplary OTG line after connection with an electronic device;

fig. 7 is a schematic structural diagram of another charging circuit according to an embodiment of the present disclosure;

fig. 8 is a flowchart of a reverse charging method according to an embodiment of the present application;

fig. 9 is a schematic structural diagram of a charging circuit according to another embodiment of the present disclosure;

fig. 10 is a flowchart of yet another reverse charging method according to an embodiment of the present application.

Detailed Description

The following description of the embodiments of the present application will be made clearly and fully with reference to the accompanying drawings, in which it is evident that the embodiments described are some, but not all, of the embodiments of the present application. All other embodiments, which can be made by one of ordinary skill in the art based on the embodiments herein without making any inventive effort, are intended to be within the scope of the present application.

The term "and/or" is herein merely an association relationship describing an associated object, meaning that there may be three relationships, e.g., a and/or B, may represent: a exists alone, A and B exist together, and B exists alone.

The terms first and second and the like in the description and in the claims of embodiments of the present application are used for distinguishing between different objects and not necessarily for describing a particular sequential order of objects. For example, the first target object and the second target object, etc., are used to distinguish between different target objects, and are not used to describe a particular order of target objects.

In the embodiments of the present application, words such as "exemplary" or "such as" are used to mean serving as examples, illustrations, or descriptions. Any embodiment or design described herein as "exemplary" or "for example" should not be construed as preferred or advantageous over other embodiments or designs. Rather, the use of words such as "exemplary" or "such as" is intended to present related concepts in a concrete fashion.

In the description of the embodiments of the present application, unless otherwise indicated, the meaning of "a plurality" means two or more. For example, the plurality of processing units refers to two or more processing units; the plurality of systems means two or more systems.

The embodiment of the application provides an electronic device, which may be a notebook computer, a mobile phone, a tablet computer, a desktop computer, a personal digital assistant (personal digital assistant, abbreviated as PDA), a vehicle-mounted computer, an intelligent wearable device, an intelligent home device, an augmented reality (augmented reality, AR)/a Virtual Reality (VR), etc., and the embodiment of the application does not limit the specific form of the electronic device.

Fig. 1 exemplarily shows an application scenario in which an electronic device is taken as a notebook computer, and an external device to be charged is taken as a mobile phone for explanation, that is, the notebook computer is taken as the mobile phone for explanation. Under the condition that a user cannot acquire an external power supply when going out, the user can use the notebook computer to charge the mobile phone if the mobile phone needs to be charged urgently to keep the cruising function. As shown in fig. 1, the notebook computer 100 includes a wired external interface 101, and the mobile phone 200 includes a wired external interface 201. When a user connects one end of the charging cable 300 to the wired external interface 101 of the notebook computer 100 and connects the other end of the charging cable 300 to the wired external interface 201 of the mobile phone 200 to be charged, the notebook computer 100 can charge the mobile phone 200 in the reverse direction in the on state or the off state.

Since the mainstream wired external interface of most of the electronic devices (such as mobile phones, tablet computers, notebook computers, etc.) is an USB Type-C interface (USB interface of Type C defined by USB association), the following description will take the wired external interface 101 as an USB Type-C interface as an example. The USB Type-C interface can adopt any one of USB transmission protocols such as USB 2.0 protocol, USB 3.0 protocol or USB 3.1 protocol, and the like, and supports functions such as charging, data transmission, display output and the like of the USB standard. The USB Type-C interface is used for supporting double-sided insertion, and the USB Type-C interface is used for supporting double-sided insertion.

Taking the USB Type-C interface on the electronic device side as an example, as shown in fig. 2, the USB Type-C interface includes: 4 VBUS pins for power, 4 GND pins for ground, two CC pins (CC 1 pin and CC2 pin), 4 pairs of TX pins and RX pins, 2 pairs of D+ (also may be referred to as DP or data positive signal) pins and D- (also may be referred to as DM or data negative signal) pins, and a pair of SBU pins (SBU 1 pin and SBU2 pin).

Wherein the VBUS pin and the GND pin are return paths for power and signals. The default VBUS voltage is 5V, but the standard allows the device to negotiate and select the VBUS voltage instead of the default value. The power supply delivery allows VBUS to have voltages up to 20V, the maximum current can also rise to 5A. Thus, the USB Type-C interface may provide a maximum power of 100W. The CC pins are used to complete the configuration channel functions defined in the USB Type-C specification, as well as the functions specified in the USB PD specification. The d+ pin and the D-pin are differential pairs for USB 2.0 connection. The signal transmitted on the d+/D-pin may be used for identification of the proprietary protocol. In addition, the TX pin and the RX pin are used for high-speed data transmission; the SBU1 pins and the SBU2 pins are auxiliary pins, and have different applications in different application scenarios, and this embodiment will not be described in detail.

Referring to fig. 3, fig. 3 schematically illustrates a configuration of a charging circuit. As shown in fig. 3, the charging circuit 10 includes a USB Type-C interface 101, a control module 102, a charging protocol module 103, a first power module 104, a second power module 105, a third power module 106, a charging management module 107, and a first switch module 108.

The control module 102 is electrically connected with the first power module 104, the second power module 105, the third power module 106 and the charging protocol module 103, the charging protocol module 103 is electrically connected with the CC pin (CC 1 pin or CC2 pin) of the USB Type-C interface 101 and the first switch module 108, the VBUS pin of the USB Type-C interface 101 is electrically connected with the charging management module 107 and the first switch module 108, and the first switch module 108 is electrically connected with the first power module 104.

Illustratively, the control module 102 is, for example, an embedded Controller (EC embedded Controller), which mainly controls the power-on timing, the keyboard, and the processing of the underlying hardware related operations, such as temperature detection, charging control, controlling the PD chip to implement the functions of the interface, etc. The control module 102 may comprise independently running software stored on its own non-volatile media. In some embodiments, the control module 102 may include one or more interfaces. The interfaces may include general purpose input output interfaces (GPIOs), eSPI (Enhanced Serial Peripheral ) interfaces, integrated circuit I2C interfaces, and the like. The electrical connection with other modules in the electronic device and the communication between the modules are realized through the interfaces. In this embodiment of the present application, the control module 102 may send switching signals to the first power module 104, the second power module 105, and the third power module 106 respectively, so as to control the working states (working or non-working) of the first power module 104, the second power module 105, and the third power module 106, and may control the charging protocol module 103 to implement an interface function. The switching signal sent by the first power module 104 is a third switching signal, the switching signal sent by the second power module 105 is a first switching signal, and the switching signal sent by the third power module 106 is a second switching signal.

Illustratively, the charging protocol module 103 is, for example, a USB-PD charging protocol module. By way of example, a USB-PD charging protocol IC may be used. The charging protocol module 103 may include one or more interfaces. The interface may include an integrated circuit I2C interface, or the like. The charging protocol chip 130 is electrically connected with the I2C interface of the control module 102 through, for example, the I2C interface and the I2C bus, so as to implement electrical connection between the charging protocol module 103 and the control module 102 and transmission between signals, for example, the control module 102 may control the charging protocol module 103 to implement an interface function. The charging protocol module 103 may implement functions such as identification of the peripheral charger.

The first power module 104 is, for example, a power chip, and is configured to output a fixed voltage, for example, a fixed voltage of 5V. When the first switch module 108 is turned on, the fixed voltage output by the first power module 104 may supply power to the external device to be charged through the VBUS pin of the USB Type-C interface 101, that is, the first power module 104 is configured to provide power to the external device to be charged.

The second power module 105 is, for example, a buck circuit, and is configured to output a fixed voltage, for example, a fixed voltage of 3.3V. The fixed voltage output by the second power module 105 provides power to the control module 102 and the charging protocol module 103 in its entirety to ensure proper operation (i.e., all functions are valid) of the control module 102 and the charging protocol module 103. For example, when the electronic device (such as a notebook computer) is in a power-on state, the control module 102 and the charging protocol module 103 are supplied with power with high efficiency. In this embodiment, the second power module 105 may also perform complete power supply for the control module 102 and the charging protocol module 103 when the electronic device (such as a notebook computer) is in a power-off state according to the control of the control module 102.

The third power module 106 is, for example, a low dropout linear regulator (low dropout regulator, LDO) for outputting a fixed voltage, for example, a fixed voltage of 3.3V. The fixed voltage output by the third power module 106 supplies power to a part of GPIOs of the control module 102 and other modules (such as clock chips) of the electronic device (such as a notebook computer), so as to ensure that some functions (operation of a start button and time) of the electronic device (such as the notebook computer) can be normally performed in a shutdown state, and the energy consumption is low.

It should be noted that, the second power module 105 and the third power module 106 are both configured to supply power to the control module 102 and other modules (e.g., a module that needs to be kept active in a power-off state, such as a clock chip) in an electronic device (e.g., a notebook computer), but the power supply relationship between the two is opposite, when the second power module 105 is turned on (active), the third power module 106 is turned off (inactive), and when the third power module 106 is turned off (inactive), the second power module 105 is turned on (active). That is, when the control module 102 enables the second power module 105, the enabling of the third power module 106 is turned off, i.e., the power supplied by the third power module 106 is changed to the power supplied by the second power module 105.

Illustratively, the charge management module 107 may be a Charger IC.

The first Switch module 108 may be, for example, a Load Switch (LS) chip, which functions as a Switch and current limiter (prevents a large current from damaging the circuit). Of course, the first switch module 108 includes, but is not limited to, an LS chip, as long as the module can have a function of on or off and a function of current limiting, which are all within the protection scope of the embodiments of the present application. For example, the first switch module 108 may be controlled to be turned on or off by the charging protocol module 103, and when the charging protocol module 103 controls the first switch module 108 to be turned on, an electronic device (such as a notebook computer) may be used as a main device to supply power to the outside.

Specifically, in the case that the electronic device is in the off state, the third power module 106 outputs a fixed voltage to supply power to a portion of the GPIOs of the control module 102 and other modules (such as clock chips) of the electronic device (such as a notebook computer), so as to ensure that some functions (operations of the on button and time) of the electronic device (such as the notebook computer) can be performed normally in the off state. When an external device to be charged (such as a mobile phone) is connected with the USB Type-C interface 101 of an electronic device (such as a notebook computer) through a charging cable, the external device to be charged recognizes that the peripheral electronic device is plugged in, and at this time, the external device to be charged can serve as a main device to provide 5V voltage to the outside, for example, a VBUS pin provides 5V voltage to the charging management module 107 of the electronic device, after the charging management module 107 recognizes that the electronic device has 5V voltage, a signal is sent to the control module 102, and the control module 102 sends a switching signal to the first power module 104 and the second power module 105 according to the signal, so that the second power module 105 completely supplies power to the control module 102 and the charging protocol module 103, so as to ensure that the control module 102 and the charging protocol module 103 work normally (i.e. all functions are valid). When the charging protocol module 103 works normally and the charging protocol module 103 recognizes that the external device to be charged is taken as the main device through a protocol (e.g., PD protocol) followed between the charging protocol module 103 and the external device to be charged, power role switching is performed after communication through the PD protocol, at this time, the electronic device (e.g., a notebook computer) becomes the main device, and then a voltage of 5V is output to the outside through the first power chip 104, the first switch module 108 and the USB Type-C interface 101 (e.g., VBUS pin), so as to charge the external device to be charged (e.g., a mobile phone), i.e., realize shutdown charging.

When the above scheme is adopted for charging the external device in reverse, the precondition is that the control module 102 and the charging protocol module 103 of the electronic device (such as a notebook computer) must be in a power-on state or be awakened by the slave device, so as to identify the access of the external device. The current main equipment, especially the equipment with battery, needs to consider long endurance and low power consumption, and other power supplies except the power supplies for maintaining the operation of the clock chip, the starting-up module and other modules are generally closed under the shutdown scene. When the slave device needs to wake up, the slave device (to be charged device) must conform to the PD protocol, and for non-standard devices, the external charging function cannot be satisfied even through the patch cord (e.g., OTG cord).

In view of this, this embodiment also provides a charging circuit, which can supply power to any external device in the on state or the off state, without being limited to the PD protocol of the USB Type-C interface, and without requiring excessive hardware cost. The structure and charging principle of the charging circuit provided in the present application will be described below.

Example 1

Referring to fig. 4, fig. 4 schematically illustrates a schematic configuration of yet another charging circuit. As shown in fig. 4, the charging circuit 10 of the electronic device 100 further includes a pull-up module 109 in addition to the USB Type-C interface 101, the control module 102, the charging protocol module 103, the first power module 104, the second power module 105, the third power module 106, the charging management module 107, and the first switch module 108. The pull-up module 109 includes a pull-up resistor R1, a first end of the pull-up resistor R1 is configured to receive a first control signal, and a second end of the pull-up resistor R1, a first port 1021 of the control module 102, and a CC pin of the USB Type-C interface 101 are coupled to the first node N1. The voltage of the first node N1 is, for example, a high level signal before the change, and the voltage of the first node N1 is, for example, a low level signal after the change. The first port 1021 of the control module 102 may be, for example, a GPIO interface, and the GPIO interface may operate with low power consumption when the electronic device is in a power-off state, and receive a change in an external level.

Since the electronic device is generally powered externally through an OTG line, the following explanation will be given taking the OTG line as an example of the charging cable 300 connecting the device 200 to be charged externally and the electronic device 100. However, the present application is not limited thereto, and the cable which can change the voltage at the first node N1 when the charging cable 300 is connected thereto is within the scope of the present application.

By way of example, in connection with fig. 5, fig. 5 shows schematically a structural diagram of an OTG line. Referring to fig. 5, otg line 300 includes USB Type-C interface 301, USB Type-a interface 302, voltage Bus (VBUS) 303, DP/DM line 304, TX/RX line 305, and GND line 306, and CC line 307, one end of CC line 307 is electrically connected to the CC pin in USB Type-C interface 301, and the other end is grounded via pull-down resistor R2 of, for example, 5.1K ohms.

Specifically, when the wired external interface 101 of the electronic device 100 is not electrically connected to the OTG line, the first node N1 is a first level signal, for example, a high level signal, because the first end of the pull-up resistor R1 receives the high level signal. In connection with fig. 6, fig. 6 illustrates a schematic diagram of the OTG line after connection with an electronic device. Referring to fig. 6, when the OTG line is inserted into the USB Type-C interface 101 of the electronic device 100, that is, when the device to be charged 200 needs to be charged, the USB Type-a interface 302 of the OTG line 300 is electrically connected with the wired external interface 201 of the device to be charged 200, and the USB Type-C interface 301 of the OTG line 300 is electrically connected with the wired external interface 101 of the electronic device 100. The pull-up resistor R1, the CC (CC 1/CC 2) pin of the wired-external interface 101, the CC pin in the USB Type-C interface 301, the CC line 307, and the pull-down resistor R2 form a path, and since the pull-down resistor R2 is grounded, the level of the first node N1 is pulled down to become a second level signal, for example, a low level signal. Since the first port 1021 of the control module 102 is electrically connected to the first node N1, the control module 102 can monitor the level change of the first node N1 (i.e., change from the first level signal to the second level signal). When the control module 102 detects that the level of the first node N1 changes, the control module 102 sends a switching signal to the second power module 105 and the third power module 106, so as to control the second power module 105 to completely supply power to the control module 102 and the charging protocol module 103, and control the third power module 106 to stop supplying power to the control module 102. After the control module 102 and the charging protocol module 103 are completely powered, the control module 102 and the charging protocol module 103 work normally, that is, the control module 102 changes from only part of interfaces to normal operation, the charging protocol module 103 changes from non-operation to normal operation, and in order to avoid that the signal received by the first end of the pull-up resistor R1 affects the level of the first node N1 (affects the protocol identification of the charging protocol module 103), at this time, the signal received by the first end of the pull-up resistor R1 changes to low level. When the charging protocol module 103 works normally, it can be identified that the external resistor with 5.1K ohms is pulled down through the CC1/CC2 pin of the wired external interface 101 (the specific protocol identification process is the same as the existing technology, which can be referred to in the existing technology and will not be repeated here), so as to determine that the USB Type-C interface 101 has OTG line access. The charging protocol module 103 reports information that the USB Type-C interface 101 has an OTG line access to the control module 102, the control module 102 sends a switching signal to the first power module 104 to control the first power module 104 to work, and sends a signal for controlling the first switch module 108 to open to the charging protocol module 103, so that the charging protocol module 103 controls the first switch module 108 to open, and thus, a 5V signal output by the first power module 104 can supply power to the device 200 to be charged through the first switch module 108, the VBUS pin of the USB Type-C interface 101, the voltage bus 303 of the OTG line, and the VBUS pin in the USB Type-C interface 301.

According to the embodiment of the application, the OTG line characteristic of the TypeC is combined (the CC line is provided with the pull-down resistor which is grounded), and the pull-up module is arranged at the CC pin of the USB Type-C interface 101, so that the level of the CC pin of the USB Type-C interface 101 changes when the OTG line is accessed and when the OTG line is not accessed, the control module 102 controls the second power module 105 to supply power to the charging protocol module 103 based on the level change, and then the charging protocol module 103 performs protocol identification, the first switch module 108 is opened, and the control module 102 controls the first power module 104 to supply power to the outside, namely, the electronic equipment such as a notebook computer, a tablet computer and a desktop computer is powered on any external equipment under a shutdown scene, and the power is not limited to the PD protocol of the TypeC port.

For the resistance value of the pull-up resistor R1, the resistance value of the pull-up resistor R1 is not limited in the embodiment of the present application, as long as the voltage at the first node N1 can be changed when the OTG line is connected to the USB Type-C interface 101, and the changed value can be recognized by the first port 1021 of the control module 102. Illustratively, the first port 1021 of the control module 102 may recognize whenever the voltage at the first node N1 changes. Alternatively, not only does the voltage at the first node N1 need to be changed, but the amount of change needs to exceed a certain threshold to be recognized by the first port 1021 of the control module 102.

In one possible implementation, the pull-up resistor R1 has a resistance value of, for example, greater than 5.1K ohms. The pull-up resistor R1 has a resistance value of 10K ohms, 20K ohms, 30K ohms, 40K ohms, 50K ohms, 60K ohms, 70K ohms, 80K ohms, 90K ohms, 100K ohms, or the like, for example. By the arrangement, the situation that the resistance of the pull-up resistor R1 is too small can be avoided, and when the OTG line is connected to the USB Type-C interface 101, the pull-down resistor R2 in the OTG line cannot achieve the effect of pull-down, so that the identification of the first port 1021 of the control module 102 is affected.

As can be seen from the foregoing, before the control module 102 monitors that the level of the first node N1 changes, the first end of the pull-up resistor R1 is configured to receive the high level signal, and after the level of the first node N1 changes, the first end of the pull-up resistor R1 is configured to receive the low level signal. The embodiment of the application for obtaining the first end signal of the pull-up resistor R1 is not specifically limited. Illustratively, the first end of the pull-up resistor R1 is electrically connected to the control module 102 and the third power module 106, for receiving the switching signal sent by the control module 102 to the third power module 106, i.e. the signal received by the first end of the pull-up resistor R1 may be the switching signal. This is because the switching signal is high when the control module 102 enables the third power module 106 and low when the control module 106 is not operating. Accordingly, a high signal may be provided to the first terminal of the pull-up resistor R1 when the control module 102 enables the third power module 106, and a low signal may be provided to the pull-up resistor R1 and the third power module 106 when the control module 102 controls the third power module 106 to be inactive.

To further ensure that the charging protocol module 103 operates properly, i.e. that the voltage at the first node N1 does not affect the charging protocol module 103 protocol identification, see fig. 7, fig. 7 schematically illustrates a further charging circuit. As shown in fig. 7, the charging circuit 10 further includes a second switch module 1091, where the second switch module 1091 is disposed between the first port 1021 and the first node N1 of the control module 102, specifically, a first end of the second switch module 1091 is electrically connected to the first port 1021 of the control module 102, a second end of the second switch module 1091 is electrically connected to the first node N1, and a control end of the second switch module 1091 is electrically connected to a first end of the pull-up resistor R1, for example. The second switching module 1091 is in an on state before the level of the first node N1 changes, and is in an off state after the level of the first node N1 changes.

When the control module 102 controls the third power module 106 to supply power to the third power module, that is, when the second switch module 1091 receives a high-level signal sent by the control module 102, the second switch module 1091 is in a conducting state, when the control module 102 controls the second power module 105 to supply power to the second power module and the charging protocol module 103, and when the control module 102 controls the third power module 106 to stop supplying power to the third power module, that is, when the control module 102 sends a low-level signal to the third power module 106 at this time, that is, when the second switch module 1091 receives a low-level signal sent by the control module 102, the second switch module 1091 is in a cut-off state, so that when the charging protocol module 103 performs protocol identification, the signal of the first port 1021 of the control module 102 can be prevented from affecting the signal of the first node N1, and thus affecting the protocol identification of the charging protocol module 103.

As for the type of the second switch module 1091, the embodiment of the present application does not limit the type of the second switch module 1091, as long as the functions of switching on and off can be achieved, which are all within the protection scope of the embodiment of the present application. The second switch module 1091 is, for example, a metal oxide semiconductor field effect transistor (Metal Oxide Semiconductor Field Effect Transistor, MOSFET), which may be, for example, an N-type MOSFET or a P-type MOSFET. The above example is described taking the second switch module 1091 as an N-type MOSFET.

Of course, if the first port 1021 of the control module 102 is set to be high-impedance (i.e., impedance is infinite) after the control module 102 is fully operational, for example, a register is configured at the first port 1021 of the control module 102, and it is also possible to avoid the signal of the first port 1021 of the control module 102 affecting the signal of the first node N1.

In order to prevent the control module 102 from monitoring the stage after the level of the first node N1 changes (the stage in which the charging protocol module 103 performs protocol recognition and the stage in which the first power module 104 externally supplies power), the signal of the first node N1 affects the signal of the first end of the pull-up resistor R1, and thus affects the working state of the third power module 106, because the signal of the first end of the pull-up resistor R1 is a signal for controlling the working state of the third power module 106. The pull-up module 109 further includes a diode 1092, a cathode of the diode 1092 is electrically connected to the first end of the pull-up resistor R1, and an anode of the diode 1092 is configured to receive a control signal. That is, when the control module 102 sends a high signal to the third power module 106 to control the third power module 106 to supply power thereto, the high signal of the anode of the diode 1092 may be transmitted to the first end of the pull-up resistor R1 through the diode 1092. When the control module 102 controls the third power module 106 to stop supplying power, the signal at the first node N1 cannot be transmitted to the anode of the diode 1092, and cannot affect the signal at the anode of the diode 1092, so that the working state of the third power module 106 cannot be affected, and the stability of the circuit is improved.

The embodiment of the present application also provides a reverse charging method, which may be applied to, for example, the charging circuit in the present embodiment, and has the same beneficial effects, and reference may be made to the foregoing embodiments of the charging circuit for details that are not described in detail in the embodiment. The reverse charging method is described below with reference to the charging circuit shown in fig. 7.

As shown in fig. 8, the reverse charging method can be implemented by:

s801, the control module 102 determines whether the electronic device is in a power-off state, and if so, step S802 is executed.

The control module 102 may monitor whether the state of the electronic device is an on state or an off state. If the electronic device is monitored to be in a power-on state, power can be supplied to the external device to be charged through the first power module 104. I.e. externally in the existing manner.

When the electronic device is in a shutdown state, external power supply can be performed according to the mode provided by the embodiment of the application.

S802, the control module 102 controls the second switch module 1091 to be turned on, so that the first port 1021 of the control module 102 is electrically connected to the first node N1, and controls the third power module 106 to supply power to a part of the interfaces of the control module 102, and controls the second power module 105 to stop supplying power to the control module 102 and the charging protocol module 103.

When the first port 1021 of the control module 102 is electrically connected to the first node N1, the control module 102 may monitor the voltage signal at the first node N1 in real time.

S803, the control module 102 monitors whether the voltage at the first node N1 changes in real time, if so, step S804 is executed; if not, the process returns to step S802.

S804, when the voltage at the first node N1 changes, the control module 102 controls the second power module 105 to supply power to the control module 102 and the charging protocol module 103, and controls the third power module 106 to stop supplying power to a part of the interfaces of the control module 102.

When the voltage at the first node N1 changes, it indicates that an OTG line may be accessed at the USB Type-C interface 101, and external power may be required at this time, so the control module 102 and the charging protocol module 103 need to be completely powered, and the charging protocol module 103 needs to identify through a protocol to determine that the OTG line is actually accessed at the USB Type-C interface 101.

S805, the charging protocol module 103 judges whether the USB Type-C interface 101 is connected with an OTG line, if so, the step S806 is executed, and if not, the step S802 is executed again.

S806, the charging protocol module 103 sends a signal that the OTG line is connected to the determined USB Type-C interface 101 to the control module 102.

Controlling the second power module 105 to supply power to the control module 102 and the charging protocol module 103, and controlling the third power module 106 to stop supplying power to a part of the interfaces of the control module 102

S807, the control module 102 controls the first power module 104 to work, and the charging protocol module 103 controls the first switch module 108 to be turned on, so that the first power module 104 supplies power to the external device to be charged through the first switch module 108 and the USB Type-C interface 101.

The method has the advantages that electronic equipment such as a notebook computer, a tablet computer and a desktop computer are used as main equipment in a shutdown scene to supply power to any external equipment, and the PD protocol of the TypeC port is not limited.

Example two

Referring to fig. 9, fig. 9 schematically illustrates a schematic configuration of yet another charging circuit. As shown in fig. 9, unlike the first embodiment, the charging circuit 10 further includes a logic non-circuit 1093, an input end of the logic non-circuit 1093, a second end of the pull-up resistor R1, and a CC pin of the USB Type-C interface 101 are coupled to the first node N1, and an output end of the logic non-circuit 1093 is electrically connected to the second power module 105 and the control module 102, respectively, without selecting an interface that can operate with low power consumption when the electronic device is in a power-off state.

Specifically, when the wired-external interface 101 of the electronic device 100 is not electrically connected to the OTG line, the first node N1 is also at a high level because the first terminal of the pull-up resistor R1 receives a high level signal. The high level of the first node N1 transitions to a low level after passing through the logic not circuit 1093, and the low level cannot enable the second power module 105, and at this time, still supplies power to a part of the interfaces of the control module 102 through the third power module 106. When the OTG line is inserted into the USB Type-C interface 101 of the electronic device 100, that is, when the device to be charged 200 needs to be charged, the USB Type-a interface 302 of the OTG line 300 is electrically connected with the wired external interface 201 of the device to be charged 200, and the USB Type-C interface 301 of the OTG line 300 is electrically connected with the wired external interface 101 of the electronic device 100. The pull-up resistor R1, the CC (CC 1/CC 2) pin of the wired-external interface 101, the CC pin in the USB Type-C interface 301, the CC line 307, and the pull-down resistor R2 constitute a path, and since the pull-down resistor R2 is grounded, the level of the first node N1 is pulled down. The low level of the first node N1 is converted to a high level after passing through the logic not circuit 1093, the high level enables the second power module 105, so that the second power module 105 completely supplies power to the control module 102 and the charging protocol module 103, the control module 102 and the charging protocol module 103 work normally, that is, the control module 102 changes from only part of the interface to work normally, the charging protocol module 103 changes from not work to work normally, and the control module 102 controls the third power module 106 to stop supplying power to the third power module (the control module 102), and at this time, the signal received by the first end of the pull-up resistor R1 becomes a low level. When the charging protocol module 103 works normally, it can be identified that the external resistor with 5.1K ohms is pulled down through the CC1/CC2 pin of the wired external interface 101 (the specific protocol identification process is the same as the existing technology, which can be referred to in the existing technology and will not be repeated here), so as to determine that the USB Type-C interface 101 has OTG line access. The charging protocol module 103 reports information that the USB Type-C interface 101 has an OTG line access to the control module 102, the control module 102 sends a switching signal to the first power module 104 to control the first power module 104 to work, and sends a signal for controlling the first switch module 108 to open to the charging protocol module 103, so that the charging protocol module 103 controls the first switch module 108 to open, and thus, a 5V signal output by the first power module 104 can supply power to the device 200 to be charged through the first switch module 108, the VBUS pin of the USB Type-C interface 101, the voltage bus 303 of the OTG line, and the VBUS pin in the USB Type-C interface 301.

According to the embodiment of the application, the OTG line characteristic of the TypeC is combined (the CC line is provided with the pull-down resistor which is grounded), and the pull-up module is arranged at the CC pin of the USB Type-C interface 101, so that the level of the CC pin of the USB Type-C interface 101 changes when the OTG line is accessed and when the OTG line is not accessed, the logic non-circuit 1093 can enable the second power module 105 to supply power to the control module 102 and the charging protocol module 103 based on the level change, and further enable the charging protocol module 103 to perform protocol identification, the first switch module 108 is turned on, and the control module 102 controls the first power module 104 to perform external power supply, namely, the electronic equipment such as a notebook computer, a tablet computer and a desktop computer can be powered on any external equipment under a shutdown scene, and the PD protocol of the TypeC port is not limited.

The embodiment of the present application also provides a reverse charging method, which may be applied to, for example, the charging circuit in the present embodiment, and has the same beneficial effects, and reference may be made to the foregoing embodiments of the charging circuit for details that are not described in detail in the embodiment. The reverse charging method is described below with reference to the charging circuit shown in fig. 9.

As shown in fig. 10, the reverse charging method may be implemented by:

s1001, the control module 102 judges whether the electronic equipment is in a shutdown state, if so, the step S1002 is executed.

When the electronic equipment is in a shutdown state, external power supply can be performed according to the mode provided by the embodiment of the application.

S1002, the control module 102 controls the third power module 106 to supply power to a part of the interfaces of the control module 102, and controls the second power module 105 to stop supplying power to the control module 102 and the charging protocol module 103.

S1003, when the voltage at the first node N1 changes, the logic not circuit 1093 controls the second power module 105 to supply power to the control module 102 and the charging protocol module 103, and the control module 102 controls the third power module 106 to stop supplying power to a part of the interfaces of the control module 102.

When the voltage at the first node N1 changes, it indicates that an OTG line may be accessed at the USB Type-C interface 101, and external power may be required at this time, so the control module 102 and the charging protocol module 103 need to be completely powered, and the charging protocol module 103 needs to identify through a protocol to determine that the OTG line is actually accessed at the USB Type-C interface 101. Thus, when the voltage at the first node N1 changes, the second power module 105 may be enabled to power the control module 102 and the charging protocol module 103 after passing through the logic not circuit 1093.

S1004, the charging protocol module 103 judges whether the USB Type-C interface 101 is connected with an OTG line, if so, the step S1005 is executed, and if not, the step S1002 is executed in a return mode.

S1005, the charging protocol module 103 sends a signal that the OTG line is connected to the determined USB Type-C interface 101 to the control module 102.

S1006, the control module 102 controls the first power module 104 to work, and the charging protocol module 103 controls the first switch module 108 to be turned on, so that the first power module 104 supplies power to the external device to be charged through the first switch module 108 and the USB Type-C interface 101.

The method has the advantages that the electronic equipment such as a notebook computer, a tablet computer and a desktop computer is used as main equipment in a shutdown scene, and any external equipment can be powered, so that the method is not limited to the PD protocol of the TypeC port.

The present embodiment also provides a computer storage medium having stored therein computer instructions which, when executed on an electronic device, cause the electronic device to perform the above-described related method steps to implement the reverse charging method in the above-described embodiments.

The present embodiment also provides a computer program product which, when run on a computer, causes the computer to perform the above-described relevant steps to implement the reverse charging method in the above-described embodiments.

In addition, embodiments of the present application also provide an apparatus, which may be specifically a chip, a component, or a module, and may include a processor and a memory connected to each other; the memory is configured to store computer-executable instructions, and when the device is running, the processor may execute the computer-executable instructions stored in the memory, so that the chip performs the reverse charging method in the above method embodiments.

The first electronic device (such as a notebook computer, etc.), the computer storage medium, the computer program product, or the chip provided in this embodiment are used to execute the corresponding method provided above, so that the beneficial effects that can be achieved by the first electronic device can refer to the beneficial effects in the corresponding method provided above, and are not repeated herein.

It will be appreciated by those skilled in the art that, for convenience and brevity of description, only the above-described division of the functional modules is illustrated, and in practical application, the above-described functional allocation may be performed by different functional modules according to needs, i.e. the internal structure of the apparatus is divided into different functional modules to perform all or part of the functions described above.

In the several embodiments provided in this application, it should be understood that the disclosed apparatus and method may be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative, e.g., the division of modules or units is merely a logical function division, and there may be additional divisions when actually implemented, e.g., multiple units or components may be combined or integrated into another apparatus, or some features may be omitted or not performed. Alternatively, the coupling or direct coupling or communication connection shown or discussed with each other may be an indirect coupling or communication connection via some interfaces, devices or units, which may be in electrical, mechanical or other form.

The above embodiments are merely for illustrating the technical solution of the present application, and not for limiting the same; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A charging circuit for use in an electronic device, comprising: the device comprises a control module, a charging protocol module, a first power module, a second power module, a third power module, a first switch module, a wired external interface and a pull-up module; the wired external interface comprises a first pin and a second pin;

the control module is respectively and electrically connected with the first power supply module, the second power supply module, the third power supply module and the charging protocol module, the charging protocol module is respectively and electrically connected with the second power supply module, the control end of the first switch module and the first pin, the first end of the first switch module is electrically connected with the first power supply module, the second end of the first switch module is electrically connected with the second pin, and the pull-up module and the first pin are coupled to a first node;

the second power module is used for completely supplying power to the control module and the charging protocol module when the electronic equipment is in a shutdown state;

before the second power module completely supplies power to the control module and the charging protocol module, the third power module supplies power to part of interfaces of the control module;

The pull-up module comprises a pull-up resistor, and a first end of the pull-up resistor is used for receiving a first control signal so that the signal of the first node is a first level signal; a second end of the pull-up resistor and the first pin are coupled to the first node;

when the first node is changed from a first level signal to a second level signal, the second power module is used for supplying power to the control module and the charging protocol module;

when the second power module supplies power to the charging protocol module, the charging protocol module is used for identifying whether a charging cable is inserted into the wired external interface, and when the charging protocol module identifies that the charging cable is inserted into the wired external interface, the charging protocol module is also used for controlling the first switch module to be conducted so that the first power module supplies power to an external device to be charged through the second pin and the charging cable when the electronic device is in a shutdown state;

the control module is used for controlling the third power module to stop supplying power to the control module when controlling the second power module to supply power to the control module and the charging protocol module, and stopping supplying power to the control module and the charging protocol module by the second power module when the third power module supplies power to the control module;

The first end of the pull-up resistor is electrically connected with the control module and the third power module;

the first control signal received by the first end of the pull-up resistor is a second switching signal sent by the control module to the third power module, wherein the second switching signal is used for controlling the third power module to supply power to the control module or stopping supplying power to the control module;

the charging circuit also comprises a second switch module or a logic NOT circuit;

when the charging circuit further comprises a second switch module, the control module comprises a first port, a first end of the second switch module is electrically connected with the first node, a second end of the second switch module is electrically connected with the first port, and a control end of the second switch module is used for receiving a second control signal; the second control signal is used for controlling the second switch module to be turned on when the signal of the first node is a first level signal, and controlling the second switch module to be turned off when the signal of the first node is changed from the first level signal to a second level signal; the first end of the pull-up resistor is used for receiving a first control signal, so that when the signal of the first node is the first level signal, the second control signal is the first control signal;

When the charging circuit further comprises a logic NOT circuit, an input end of the logic NOT circuit is coupled to the first node; the output end of the logic NOT circuit is electrically connected with the second power supply module; when the first node is changed from a first level signal to a second level signal, the logic non-circuit is used for controlling the second power supply module to supply power for the control module and the charging protocol module.

2. The charging circuit of claim 1, wherein the pull-up module further comprises a diode having an anode for receiving the first control signal, a cathode electrically connected to the first end of the pull-up resistor.

3. The charging circuit of claim 1, wherein the pull-up resistor has a resistance greater than 5.1 kiloohms.

4. A charging circuit according to any of claims 1-3, wherein the control module is configured to collect a signal of the first node, and when the first node changes from a first level signal to a second level signal, is further configured to send a first switch signal to the second power module, so that the second power module supplies power to the control module and the charging protocol module.

5. The charging circuit of claim 1, wherein the second switch module comprises a metal oxide semiconductor field effect transistor.

6. The charging circuit of claim 1, wherein the charging protocol module comprises a USB-PD protocol module.

7. The charging circuit of claim 1, wherein the second power module comprises a BUCK circuit.

8. The charging circuit of claim 1, wherein the third power supply module comprises a low dropout linear regulator.

9. An electronic device comprising a charging circuit as claimed in any one of claims 1-8.

10. The electronic device of claim 9, wherein the electronic device comprises a notebook computer.

11. A reverse charging method, characterized by being applied to the electronic device according to claim 9 or 10, comprising:

when the first node is detected to be changed from a first level signal to a second level signal, the electronic equipment supplies power for the control module and the charging protocol module;

when the charging cable is identified to be inserted into the wired external interface, the electronic equipment supplies power for the external equipment to be charged through the second pin and the charging cable in the power-off state.

12. A reverse charging system comprising the electronic device according to claim 9 or 10, and an external device electrically connected to the electronic device through the wired external interface;

and in a shutdown state, the electronic equipment is used for reversely charging the external equipment.

13. The reverse charging system according to claim 12, further comprising an OTG line for reverse charging the external device through the OTG line in a shutdown state when one end of the OTG line is electrically connected with the electronic device and the other end is electrically connected with the external device.