Charging method and terminal device

Abstract

Embodiments of the present application provide a charging method. The method is used for a first terminal device to charge a second terminal device. The first terminal device comprises a battery, a first switched-capacitor circuit, and a wired charging interface. The first switched-capacitor circuit is electrically connected between the battery and the wired charging interface. The wired charging interface is connected to the second terminal device by means of an OTG data line. The method comprises: in response to a reverse charging mode of the first terminal device selected by a user, determining that the first terminal device is a master device in an OTG connection for providing electric energy; and controlling the first switched-capacitor circuit to increase a first output voltage of the battery to a second output voltage, and outputting the second output voltage to the wired charging interface so as to transmit the second output voltage to the second terminal device by means of the OTG data line. The charging method provided by the present application can improve the charging power of reverse charging, realize higher reverse charging efficiency, and reduce the problem of heating during reverse charging.

Description

Charging method and terminal device

[0001] This application claims priority to the Chinese patent application with application number 202310985783.2 filed with the State Intellectual Property Office of China on August 7, 2023, and priority to the Chinese patent application with the invention name “A Charging Method and Terminal Device”, all contents of which are incorporated by reference into this application. Technical Field

[0002] Embodiments of the present application relate to the field of charging technology, and more specifically, to a charging method and terminal device. Background Art

[0003] OTG, short for "On-The-Go," refers to a universal serial bus (USB) interface technology that enables direct connection and data transfer between devices. The OTG interface allows an OTG-enabled device (such as a smartphone, tablet, or other terminal device) to act as a host and connect to other USB devices (such as flash drives, keyboards, mice, and terminal devices) as slaves, enabling data transfer and file sharing. Furthermore, the OTG interface allows the host device to power other devices via the USB OTG cable, enabling wired reverse charging.

[0004] Currently, wired reverse charging for electronic devices like smartphones and tablets is limited by the power and temperature of components like the buck charging chip and inductor in the charging circuit, resulting in low power consumption, typically under 7.5W. Furthermore, reverse charging efficiency is low, typically below 90%, resulting in significant heat generation during wired reverse charging.

[0005] Summary of the Invention

[0006] The embodiments of the present application provide a charging method and a terminal device, which can improve the charging power of wired reverse charging, and the reverse charging efficiency is higher, reducing the heat problem during wired reverse charging.

[0007] In a first aspect, a charging method is provided, which is applied to a first terminal device charging a second terminal device, the first terminal device including a battery, a first switching capacitor circuit and a wired charging interface, the first switching capacitor circuit being electrically connected between the battery and the wired charging interface, the wired charging interface being connected to the second terminal device via an OTG data line, the method comprising: in response to a user-selected reverse charging mode of the first terminal device, determining that the first terminal device is a main device for providing power in the OTG connection; controlling the first switching capacitor circuit to increase the first output voltage of the battery to a second output voltage, and outputting the second output voltage to the wired charging interface for transmission to the second terminal device via the OTG data line.

[0008] In some possible implementations, the first switched capacitor circuit includes a charge pump circuit, and the first terminal device further includes a first control circuit, which is used to control the on-off state of one or more transistors in the charge pump circuit.

[0009] In the embodiment of the present application, the first switched capacitor circuit is used as a boost circuit during reverse charging. Compared with the boost circuit, the first switched capacitor has a wider boost range and higher conversion efficiency, so that the reverse charging power of the terminal device is higher and the heat problem is smaller.

[0010] In some possible implementations, the first terminal device also includes a mode switching control circuit, which is used to switch the working mode of the first switching capacitor circuit. The working mode of the first switching capacitor circuit includes a buck mode or a boost mode. In the buck mode, the output end of the first switching capacitor circuit is the battery to achieve forward charging. In the boost mode, the input end of the first switching capacitor circuit is the battery to achieve reverse charging. Controlling the first switching capacitor circuit to increase the first output voltage of the battery to the second output voltage includes: determining that the working state of the battery is a discharge state; controlling the mode switching control circuit to determine that the input end of the first switching capacitor circuit is the battery and the output end is the wired charging interface, so that the first switching capacitor circuit switches from the buck mode to the boost mode to increase the first output voltage of the battery to the second output voltage.

[0011] In some possible implementations, the mode switching control circuit and the first switching capacitor circuit are integrated into the first switching capacitor chip, and controlling the mode switching control circuit so that the first switching capacitor circuit switches from the buck mode to the boost mode includes: controlling the mode switching control circuit in the first switching capacitor chip so that the working mode of the first switching capacitor chip switches from the forward charging mode to the reverse charging mode, and when the first switching capacitor chip is in the forward charging mode, the first switching capacitor circuit is in the buck mode, and when the first switching capacitor chip is in the reverse charging mode, the first switching capacitor circuit is in the boost mode.

[0012] The embodiment of the present application uses a mode switching circuit to quickly switch the operating mode of the first switch capacitor or the first switch capacitor chip to achieve rapid switching between the forward charging mode and the reverse charging mode of the terminal device, and save space in the terminal device.

[0013] In some possible implementations, the first terminal device is further provided with a first charging switching circuit and a first integrated circuit, the first integrated circuit and the first switching capacitor circuit are connected in parallel between the battery and the wired charging interface, the first charging switching circuit is used to turn on the first integrated circuit and one of the first switching capacitor circuits, the first integrated circuit is used to forward charge the first terminal device, after determining that the first terminal device is the main device for providing power in the OTG connection, the method also includes: controlling the first charging switching circuit, turning off the first integrated circuit and turning on the first switching capacitor circuit, so that the first terminal device switches from using the first integrated circuit for forward charging to using the first switching capacitor circuit for reverse charging.

[0014] In the embodiment of the present application, the first charging switching circuit is used to switch between the two charging branches, so as to switch between the forward charging mode and the reverse charging mode of the terminal device.

[0015] In some possible implementations, the first terminal device is further provided with a first step-up chopper boost circuit, which is connected in parallel with the first switch capacitor circuit between the battery and the wired charging interface. Before controlling the first switch capacitor circuit to increase the first output voltage of the battery to the second output voltage, the method also includes: controlling the first boost circuit to increase the first output voltage to a third output voltage, and outputting the third output voltage to the wired charging interface, the third output voltage being less than the second output voltage; controlling the first switch capacitor circuit to increase the first output voltage of the battery to the second output voltage includes: when it is determined that the second terminal device supports a charging voltage of the second output voltage, controlling the first switch capacitor circuit to increase the first output voltage of the battery to the second output voltage.

[0016] In the handshake process between the first terminal device and the second terminal device, in the embodiment of the present application, reverse charging is performed in advance through the first boost circuit until it is determined that the second terminal device can support the second output voltage, thereby improving the efficiency of reverse charging.

[0017] In some possible implementations, the first boost circuit is provided with a boost protection circuit. When the first terminal device switches from using the first boost circuit for reverse charging to using the first switched capacitor circuit for reverse charging, the boost protection circuit is used to protect the first boost circuit during the switching process.

[0018] In the embodiment of the present application, a boost protection circuit is used to prevent the first boost circuit from burning out, thereby ensuring the efficiency of reverse charging.

[0019] In some possible implementations, the boost protection circuit includes any one or more of a metal oxide semiconductor field effect transistor (MOS), a diode, a transistor, and a resistor.

[0020] In some possible implementations, the ratio of the second output voltage to the first output voltage is any one or more of 4:1, 3:1, and 2:1.

[0021] In some possible implementations, the first terminal device identifies the second terminal device through any one or several charging protocols including the power transmission PD protocol, the fast charging QC protocol, and the battery charging BC protocol.

[0022] In some possible implementations, the method further includes: acquiring power information of the first terminal device or the second terminal device; and determining the second output voltage according to the power information of the first terminal device or the second terminal device.

[0023] In a second aspect, a terminal device is provided, which includes: a battery; a wired charging interface, which is connected to another terminal device through an OTG data line; a first switching capacitor circuit, which is electrically connected between the battery and the wired charging interface; a control module, which is used to respond to a reverse charging mode of the first terminal device selected by a user, determine that the first terminal device is the main device for providing power in the OTG connection, and control the first switching capacitor circuit to increase the first output voltage of the battery to a second output voltage, and output the second output voltage to the wired charging interface for transmission to the other terminal device through the OTG data line.

[0024] In some possible implementations, the first switched capacitor circuit includes a charge pump circuit, and the control module includes a first control circuit, which is used to control the on-off state of one or more transistors in the charge pump circuit.

[0025] In some possible implementations, the terminal device also includes: a mode switching control circuit, which is used to switch the working mode of the first switching capacitor circuit, and the working mode of the first switching capacitor circuit includes a buck mode or a boost mode. In the buck mode, the first switching capacitor circuit is used to output a supply voltage to the battery to achieve forward charging, and in the boost mode, the first switching capacitor circuit is used to receive a supply voltage from the battery to achieve reverse charging; the control module is specifically used to: determine that the working state of the battery is a discharge state; control the mode switching control circuit, determine that the input end of the first switching capacitor circuit is the battery and the output end is the wired charging interface, so that the first switching capacitor circuit switches from the buck mode to the boost mode to increase the first output voltage of the battery to the second output voltage.

[0026] In some possible implementations, the terminal device includes: a first switching capacitor chip, the first switching capacitor chip including the first switching capacitor circuit and the mode switching control circuit; the control module is specifically used to: switch the working mode of the first switching capacitor chip from a forward charging mode to a reverse charging mode by controlling the mode switching control circuit in the first switching capacitor chip, so that the first switching capacitor chip increases the first output voltage of the battery to a second output voltage, and when the first switching capacitor chip is in the forward charging mode, the first switching capacitor circuit is in a buck mode, and when the first switching capacitor chip is in the reverse charging mode, the first switching capacitor circuit is in a boost mode.

[0027] In some possible implementations, the terminal device also includes: a first integrated circuit, which is connected in parallel with the first switching capacitor circuit between the battery and the wired charging interface, and the first integrated circuit is used to forward charge the first terminal device; a first charging switching circuit, which is used to turn on the first integrated circuit and one of the first switching capacitor circuits; the control module is also used to: control the first charging switching circuit, turn off the first integrated circuit and turn on the first switching capacitor circuit, so that the first terminal device switches from using the first integrated circuit for forward charging to using the first switching capacitor circuit for reverse charging.

[0028] In some possible implementations, the terminal device also includes: a first step-up chopper boost circuit, which is connected in parallel with the first switched capacitor circuit between the battery and the wired charging interface; before the control module controls the first switched capacitor circuit to increase the first output voltage of the battery to the second output voltage, the control module is also used to: control the first boost circuit to increase the first output voltage to a third output voltage, and output the third output voltage to the wired charging interface, and the third output voltage is less than the second output voltage; the control module is specifically used to: when it is determined that the other terminal device supports a charging voltage of the second output voltage, control the first switched capacitor circuit to increase the first output voltage of the battery to the second output voltage.

[0029] In some possible implementations, the first boost circuit is provided with a boost protection circuit. When the terminal device switches from using the first boost circuit for reverse charging to using the first switched capacitor circuit for reverse charging, the boost protection circuit is used to protect the first Boost circuit during the switching process.

[0030] In some possible implementations, the boost protection circuit includes any one or more of a metal oxide semiconductor field effect transistor (MOS), a diode, a transistor, and a resistor.

[0031] In some possible implementations, the ratio of the second output voltage to the first output voltage is any one or more of 4:1, 3:1, and 2:1.

[0032] In some possible implementations, the terminal device identifies the other terminal device through any one or several charging protocols including the power transmission PD protocol, the fast charging QC protocol, and the battery charging BC protocol.

[0033] In some possible implementations, the control module is further configured to: obtain power information of the terminal device or the other terminal device, and determine the second output voltage according to the power information of the terminal device or the other terminal device.

[0034] In a third aspect, a terminal device is provided, comprising: a processor, a memory and a transceiver, wherein the memory is used to store a computer program, and the processor is used to call and run the computer program stored in the memory to execute the method in the above-mentioned first aspect or any possible implementation of the first aspect.

[0035] In a fourth aspect, a chip is provided, which obtains an instruction and executes the instruction to implement the method in the above-mentioned first aspect or any possible implementation manner of the first aspect.

[0036] Optionally, as an implementation, the chip includes a processor and a data interface, and the processor reads instructions stored in the memory through the data interface to execute the method in the above-mentioned first aspect or any possible implementation of the first aspect.

[0037] Optionally, as an implementation method, the chip may also include a memory, in which instructions are stored, and the processor is used to execute the instructions stored in the memory. When the instructions are executed, the processor is used to execute the method in the above-mentioned first aspect or any possible implementation method of the first aspect.

[0038] In a fifth aspect, a computer program product comprising instructions is provided. When the instructions are executed by a computing device or a computing device cluster, the computing device or the computing device cluster executes the method in the above-mentioned first aspect or any possible implementation of the first aspect.

[0039] In a sixth aspect, a computer-readable storage medium is provided, comprising computer program instructions. When the computer instructions are executed by a computing device or a computing device cluster, the computing device or the computing device cluster executes the method in the above-mentioned first aspect or any possible implementation of the first aspect.

[0040] By way of example, these computer-readable storage media include, but are not limited to, one or more of the following: read-only memory (ROM), programmable ROM (PROM), erasable PROM (EPROM), Flash memory, electrically EPROM (EEPROM), and a hard drive.

[0041] Optionally, as an implementation manner, the above-mentioned storage medium may specifically be a non-volatile storage medium. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] FIG1 is a schematic block diagram of an OTG connection provided in an embodiment of the present application.

[0043] FIG2 is a schematic block diagram of an operation interface provided in an embodiment of the present application.

[0044] FIG3 is a schematic block diagram of a reverse charging system provided in an embodiment of the present application.

[0045] FIG4 is a schematic block diagram of a charging method provided in an embodiment of the present application.

[0046] FIG5 is a schematic diagram of a first switched capacitor circuit provided in an embodiment of the present application.

[0047] FIG6 is a schematic block diagram of a mode switching control circuit provided in an embodiment of the present application.

[0048] FIG7 is a schematic block diagram of a charging circuit for implementing reverse charging and forward charging provided in an embodiment of the present application.

[0049] FIG8 is a schematic block diagram of handshaking between terminal devices through a reverse charging protocol provided in an embodiment of the present application.

[0050] FIG9 is a schematic block diagram of another charging circuit provided in an embodiment of the present application.

[0051] FIG10 is a schematic diagram of a boost protection circuit provided in an embodiment of the present application.

[0052] FIG11 is a schematic diagram of a terminal device provided in an embodiment of the present application.

[0053] FIG12 is a schematic diagram of another terminal device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0054] The following will describe the technical solutions in the embodiments of this application in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0055] Unless otherwise specified, all technical and scientific terms used in the embodiments of the present application have the same meaning as those commonly understood by those skilled in the art in the art of the present application. The terms used in this application are only for the purpose of describing specific embodiments and are not intended to limit the scope of this application.

[0056] It should be understood that in the various embodiments of the present application, the size of the serial number of each process does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0057] Additionally, in the embodiments of this application, words such as "exemplary" and "for example" are used to indicate examples, illustrations, or descriptions. Any embodiment or design described in this application as "exemplary" should not be construed as being preferred or advantageous over other embodiments or designs. Rather, the use of the word "exemplary" is intended to present concepts in a concrete manner.

[0058] In the embodiments of the present application, “corresponding” and “relevant” may sometimes be used interchangeably. It should be noted that when the distinction between them is not emphasized, the meanings they intend to express are consistent.

[0059] The network architecture and business scenarios described in the embodiments of the present application are intended to more clearly illustrate the technical solutions of the embodiments of the present application, and do not constitute a limitation on the technical solutions provided in the embodiments of the present application. A person skilled in the art will appreciate that, with the evolution of the network architecture and the emergence of new business scenarios, the technical solutions provided in the embodiments of the present application are equally applicable to similar technical problems.

[0060] References to "one embodiment" or "some embodiments" in this specification mean that a particular feature, structure, or characteristic described in conjunction with that embodiment is included in one or more embodiments of the present application. Thus, phrases such as "in one embodiment," "in some embodiments," "in other embodiments," and "in yet other embodiments" appearing in various places in this specification do not necessarily refer to the same embodiment, but rather mean "one or more but not all embodiments," unless otherwise specifically emphasized. The terms "including," "comprising," "having," and variations thereof mean "including but not limited to," unless otherwise specifically emphasized.

[0061] In this application, "at least one" means one or more, and "more" means two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can mean: including the existence of A alone, the existence of A and B at the same time, and the existence of B alone, where A and B can be singular or plural. The character " / " generally indicates that the previous and next associated objects are in an "or" relationship. "At least one of the following items" or similar expressions refers to any combination of these items, including any combination of single or plural items. For example, at least one of a, b, or c can mean: a, b, c, ab, ac, bc, or abc, where a, b, c can be single or multiple.

[0062] In order to facilitate understanding of the technical solution of this application, the professional terms mentioned in this application are briefly explained below.

[0063] 1.OTG

[0064] OTG, short for "On-The-Go," refers to a universal serial bus (USB) interface technology that enables direct connection and data transfer between devices. The OTG interface allows an OTG-enabled device (such as a smartphone, tablet, or other terminal device) to act as a host and connect to other USB devices (such as flash drives, keyboards, mice, and other terminal devices) as slaves, enabling data transfer and file sharing.

[0065] OTG technology allows data transfer between devices without a host. For example, a digital camera can be connected directly to a printer. Using OTG, the USB ports between the two devices can be connected, allowing photos to be printed instantly. Alternatively, data from a digital camera can be sent to a USB-connected mobile hard drive. OTG technology can be used to expand the functionality of smart terminals by adding USB-connected accessories.

[0066] Figure 1 shows a schematic diagram 100 of an OTG connection. As shown in Figure 1, the wired charging interface 112 of the first terminal device 110 is connected to the wired charging interface 132 of the second terminal device 130 via an OTG data cable 120. In this case, the first terminal device 110 can act as the master device of the OTG connection, responsible for data transmission, device management, and power supply, etc., and the second terminal device 130 can act as the slave device of the OTG connection, responsible for passively receiving instructions from the master device and executing the operations corresponding to the instructions. During the process of connecting the first terminal device 110 and the second terminal device 120 via the OTG data cable 120, the first terminal device 110 will send a request to the second terminal device 120 to inquire whether the second terminal device 130 supports the OTG function. If it does, the first terminal device 110 will switch to master device mode to power the second terminal device 130. In some embodiments, the wired charging interface 112 and the wired charging interface 132 include but are not limited to a Mini USB interface, a Micro USB interface, a Dock interface, a Lightning interface, or a Type-C interface.

[0067] As shown in the charging icon in the upper right corner of the second terminal device 130 in Figure 1, in an embodiment of the present application, the OTG interface can enable the first terminal device 110 as the main device to power the second terminal device 130 through the OTG data line 120, thereby realizing wired reverse charging.

[0068] 2. Reverse charging

[0069] Reverse charging refers to the aforementioned first terminal device 110 being used as a power source to charge the second terminal device 130, for example, via a wired OTG data cable or wireless reverse charging using electromagnetic waves emitted by a wireless coil in the terminal device. Correspondingly, forward charging refers to powering the terminal device via a wired or wireless charger.

[0070] In an embodiment of the present application, a user can select an operating mode of the first terminal device on the user interface of the first terminal device 110 to power the first terminal device 110. Figure 2 shows a schematic diagram of an operating interface 200. As shown in Figure 2, in response to the user selecting the USB connection mode in the user interface 200, the first terminal device 110 determines its operating mode. For example, if the user selects the "Charge Only" option in the USB connection mode, the first terminal device 110 can act as a power receiver, receiving power from a charger or other terminal device; if the user selects the "Reverse Charge" option in the USB connection mode, the first terminal device can act as a power supply, providing power to a second terminal device or other terminal device. In other embodiments of the present application, after the user selects the "Reverse Charge" option, the first terminal device may also prompt the user to select or adjust a power supply strategy, such as setting a power limit for enabling reverse charging or a power limit for terminating reverse charging. When the first terminal device 110 and the second terminal device 130 are connected via the OTG data cable 120, the user interfaces of the first terminal device 110 and the second terminal device 130 can simultaneously display the operating modes shown in FIG. 2 for the user to select. Alternatively, the user can select the operating mode shown in FIG. 2 from the setting options in the user interfaces of the first terminal device 110 and the second terminal device 130.

[0071] In other embodiments of the present application, a user can select the "Reverse Charge" option on the user interface of the second terminal device 130 and the "Charge Only" option on the user interface of the first terminal device 110. This allows the second terminal device 130 to function as a power source, providing power to the first terminal device 110, which functions as a power receiver. For example, when the first terminal device 110 is providing power to the second terminal device 130 and the user needs to switch between power sources and power receivers, the user can first change the "Reverse Charge" option to "Charge Only" on the user interface of the first terminal device 110, and then change the "Charge Only" option to "Reverse Charge" on the user interface of the second terminal device 130. In other words, the user can select either terminal device at either end of the OTG cable as the power source. That is, by selecting or changing the "Reverse Charge" or "Charge Only" option on the user interface of that terminal device, the user can select or switch between the power source and power receiver for reverse charging between any two terminals.

[0072] FIG3 shows a schematic block diagram of a reverse charging system 300 , which illustrates an internal system architecture diagram of a first terminal device 110 and a second terminal device 130 .

[0073] As shown in FIG3 , the OTG data line in the embodiment of the present application includes a voltage bus (VBUS), a D+ line (also called a positive data line or a positive data signal line), a D- line (also called a negative data line or a negative data signal line), an identification line (ID) line (also called a configuration channel (CC) line), and a ground (GND) line. The D+ line and the D- line can be used for data transmission.

[0074] As shown in FIG3 , the first terminal device 110 and the second terminal device 130 in FIG3 respectively include a control module 111 and a control module 131. The control module can be used to implement various functions for the terminal device, such as processing communication protocols and communication data, or controlling the entire terminal device, executing software programs, and processing software program data; or assisting in completing computing tasks, such as image processing or audio processing.

[0075] As shown in Figure 3, the first terminal device 110 and the second terminal device 130 further include a charging circuit module 113 and a charging circuit module 133 and a battery 114 and a battery 134, respectively. The charging circuit module includes a charging circuit, which is used to output a power supply signal to the battery in the case of forward charging, or to receive the power supply signal of the battery and output it to the wired charging interface in the case of reverse charging. For example, the control module 131 can send an output instruction to the charging circuit module 133 to determine that the input end of the charging circuit module is an external power supply signal and the output end is a battery, so as to instruct the charging circuit in the charging circuit module to output a power supply signal to the battery (for example, a power supply signal with a voltage of 4.5V and a current of 1.5A). For another example, the control module 111 can send an input instruction to the charging circuit module 113 to instruct the charging circuit in the charging circuit module to receive the power supply signal of the battery, amplify the power supply signal and transmit it to the wired charging interface 112. In an embodiment of the present application, the charging circuit module can also be a charging chip, such as a buck charging chip or a switched capacitor chip.

[0076] Taking the first terminal device as an example, when the first terminal device 110 reverse charges the second terminal device 130, the control module 111 can send an input instruction to the charging circuit module 113 to instruct the charging circuit in the charging circuit module to receive the power signal from the battery 114, amplify the power signal, and transmit it to the wired charging interface 112. As another example, if the wired charging interface 112 of the first terminal device 110 is connected to a charger, the control module 111 can send an output instruction to the charging circuit module 113 to determine that the input end of the charging circuit module is the external power signal and the output end is the battery, thereby instructing the charging circuit in the charging circuit module to output a power signal (e.g., a power signal with a voltage of 4.5V and a current of 1.5A) to the battery 114.

[0077] Referring to Figure 3, the charging circuit module 113 and the charging circuit module 133 are connected via a VBUS line. The VBUS line is used to transmit the power supply voltage. In other words, if the first terminal device is the power supply end, the battery 114 outputs the power supply voltage to the charging circuit module 113, and the charging circuit module 113 transmits the power supply voltage to the charging circuit module 133 via the VBUS line and outputs it to the battery 134.

[0078] It is worth noting that Figure 3 is merely a schematic diagram of a reverse charging system provided by an embodiment of the present application, and the devices, components, modules, etc. shown in the figure do not constitute any limitation. For example, the first terminal device and the second terminal device in the reverse charging system may further include a USB PHY module and be connected via a D+ line and a D- line for underlying signal conversion. For another example, the first terminal device and the second terminal device in the reverse charging system may further include a reverse charging protocol module for matching the reverse charging voltages of the first terminal device and the second terminal device.

[0079] The terminal device in the embodiments of the present application may also be referred to as user equipment (UE), access terminal, user unit, user station, mobile station, mobile station, remote station, remote terminal, mobile device, user terminal, terminal, wireless communication device, user agent or user device. The terminal device in the embodiments of the present application can be a mobile phone, a tablet computer, a computer with wireless transceiver function, a virtual reality (VR) terminal device, an augmented reality (AR) terminal device, a wireless terminal in industrial control, a wireless terminal in self-driving, a wireless terminal in remote medical, a wireless terminal in a smart grid, a wireless terminal in transportation safety, a wireless terminal in a smart city, a wireless terminal in a smart home, a cellular phone, a cordless phone, a session initiation protocol (SIP) phone, a wireless local loop (WLL) station, a personal digital assistant (PDA), a handheld device with wireless communication function, a computing device or other processing device connected to a wireless modem, a vehicle-mounted device, a vehicle-mounted communication device, a roadside unit (ROU), or a similar device. unit, RSU), vehicle-mounted communication processing chip, wearable device, terminal equipment in 5G network or terminal equipment in the future evolved public land mobile communication network (public land mobile network, PLMN), etc.

[0080] Furthermore, the terminal device can also be a terminal device in the Internet of Things (IoT) system. IoT is an important component of the future development of information technology. Its main technical feature is to connect objects to the network through communication technology, thereby realizing an intelligent network that interconnects people, machines, and things.

[0081] Currently, during reverse charging, if the first terminal device 110 serves as the primary power supply, the charging circuit module 113 shown in FIG3 generally employs a boost circuit, while the charging circuit module 133 generally employs a buck circuit. In this case, the battery 114 outputs a supply voltage (approximately 4 to 4.5 V) to the charging circuit module 113. The boost circuit in the charging circuit module 113 boosts the battery supply voltage and transmits the boosted supply voltage to the charging circuit module 133 via the VBUS line. The buck circuit in the charging circuit module 133 then steps down the boosted supply voltage to the supply voltage required by the battery 134 (approximately 4 to 4.5 V) and outputs it to the battery 134. Thus, during reverse charging, the voltage output by the first terminal device increases. For example, the boost circuit can increase the supply voltage to 5 V or higher, thereby increasing the charging power output by the first terminal device and, to a certain extent, accelerating the charging speed of the second terminal device.

[0082] However, due to the limitations of the boost circuit and the buck circuit themselves, the charging power output by the first terminal device is generally within 7.5W. The reason is that the boost circuit and the buck circuit realize the process of boosting and bucking through the internal inductor. Due to the presence of the inductor, the power loss generated during the boost and buck process is proportional to the square of the difference between the output voltage and the input voltage of the boost and buck circuits. The greater the difference between the output voltage and the input voltage, the lower the conversion efficiency of the boost circuit and the buck circuit. Therefore, the output voltage of the boost circuit and the input voltage of the buck circuit are generally limited to about 5V, resulting in the charging power generally being within 7.5W and unable to be further improved. Moreover, the conversion efficiency is generally below 90%, which leads to the terminal device still having problems with slow charging speed, large charging loss, and obvious device heating during reverse charging, thereby reducing the user experience.

[0083] In order to solve the above-mentioned problems of low charging power and low charging efficiency, the present application proposes a charging method 400, which can improve the charging power of wired reverse charging, and the efficiency of reverse charging is higher, reducing the heating problem during wired reverse charging. The charging method 400 is applied to the first terminal device shown in Figure 1 to charge the second terminal device, and can also be applied to the second terminal device to charge the first terminal device. This article takes the first terminal device charging the second terminal device as an example to introduce the embodiment. Among them, in the charging method 400, the charging circuit in the charging circuit module 113 includes a first switched capacitor circuit for boosting. Optionally, the charging circuit in the charging circuit module 133 can be a buck circuit, or a second switched capacitor circuit for reducing voltage. The charging method 400 includes steps 410 and 420.

[0084] Step 410: In response to the reverse charging mode of the first terminal device selected by the user, the first terminal device is determined to be a main device for providing power in the OTG connection.

[0085] Step 420: Control the first switched capacitor circuit to increase the first output voltage of the battery to a second output voltage, and output the second output voltage to the wired charging interface for transmission to the second terminal device through the OTG data line.

[0086] On the one hand, the first switched capacitor circuit uses a capacitor as an energy storage element to convert voltage and current. The switched capacitor circuit can increase the output voltage of the battery (approximately 4 to 4.5V) by N times (N≥2), which is much larger than the 5V output voltage of the boost circuit. At the same time, the conversion efficiency can reach more than 97%. Therefore, method 400 not only improves the charging power by boosting the voltage through the first switched capacitor circuit, but also solves the problem of heating of the charging circuit module.

[0087] Correspondingly, for the second terminal device, when the wired charging interface of the second terminal device receives the doubled supply voltage output by the first terminal device, if the charging circuit in the charging circuit module 133 is a second switched capacitor circuit, the second switched capacitor circuit reduces the N-fold increased supply voltage by N times to obtain the charging voltage required by the battery 134. In this case, because the conversion efficiency of the second switched capacitor circuit can reach over 97%, the heating problem of the charging circuit module of the second terminal device is also effectively solved.

[0088] In some other embodiments of the present application, for the second terminal device, the charging circuit in the charging circuit module 133 may also be the above-mentioned step-down (buck) circuit.

[0089] It is worth noting that the voltage / current values ​​of the reverse charging of the terminal device involved in this application are examples and do not limit the scope of protection of this application. For example, the first terminal device can provide 9V / 2A reverse charging capability, or 9V / 3A reverse charging capability. For another example, the first terminal device can also provide 5V / 1A or 5V / 1.5A reverse charging capability through a boost / buck circuit. In other words, the power of the electrical energy provided by the first terminal device can be any value.

[0090] The charging circuit module in the first terminal device is introduced below with reference to specific embodiments.

[0091] FIG5 shows a schematic diagram of a first switched capacitor circuit 500, wherein the first switched capacitor circuit includes a charge pump circuit and a first control circuit 550. The first control circuit includes a plurality of gate drivers connected to a plurality of transistors in the charge pump circuit, and is used to provide a drive signal to control the on and off states of the plurality of transistors, so that the charge pump circuit can halve or double the output voltage. The drive signal provided by the first control circuit can be determined by the control module in FIG3, or alternatively, the first control circuit can be a part of the control module.

[0092] Exemplarily, as shown in (a) in Figure 5, the first switched capacitor circuit is a dual-phase switched capacitor circuit or a dual-phase charge pump circuit, including an input terminal VIN, an output terminal VOUT, transistors 501 to 504, transistors 505 to 508, and first capacitors 510 and 515 connected in series. The phases of the drive signals of the two branches of the dual-phase switched capacitor circuit differ by 180° from each other. Taking one of the branches as an example, the first end of transistor 501 is connected to the output terminal VOUT, the connection point between transistor 501 and transistor 502 is connected to the first end of the first capacitor 510, the connection point between transistor 502 and transistor 503 is connected to the input terminal VIN, and the connection point between transistor 503 and transistor 504 is connected to the second end of the first capacitor 510.

[0093] In the first switched capacitor circuit shown in FIG5(a), a ratio of output voltage to input voltage of 2:1 can be achieved. The principle is that the first switched capacitor circuit is configured to operate in a first phase and a second phase, wherein the phases of the two branches differ by 180° from each other. That is, when the first branch is in the first phase, the second branch is in the second phase, or when the first branch is in the second phase, the second branch is in the first phase.

[0094] Taking the first branch as an example, during the first phase, transistors 501 and 503 are off, while transistors 502 and 504 are on. Since transistors 502 and 504 are on, a first conductive path is established between VIN and first capacitor 510. The first conductive path is formed by input terminal VIN, transistor 502, first capacitor 510, and transistor 504. Current flows from VIN to first capacitor 510 through the first conductive path. During the first phase, first capacitor 510 is charged to the supply voltage of VIN, and energy is stored in first capacitor 510 accordingly.

[0095] During the second phase, transistors 501 and 503 are turned on, while transistors 502 and 504 are turned off. Since transistors 501 and 503 are turned on, a second conductive path is established. The second conductive path is formed by input terminal VIN, transistor 503, first capacitor 510, transistor 501, and output terminal VOUT. During the second phase, the voltage across first capacitor 510 is the supply voltage at terminal VIN. Since one end of first capacitor 510 is connected to terminal VIN, the output voltage at terminal VOUT is double the supply voltage at terminal VIN.

[0096] Therefore, the first branch has no output voltage at VOUT during the first phase, while the second branch has an output voltage at VOUT of twice the input voltage. The second branch has a zero output voltage during the second phase, while the first branch has an output voltage of twice the input voltage. Ultimately, combining the two branches results in a dual-phase switched capacitor circuit (Figure 5(a)) with an output voltage that is twice the input voltage.

[0097] Similarly, if the input terminal VIN and the output terminal VOUT in FIG5(a) are swapped, a ratio of the output voltage to the input voltage of 1:2 can be achieved, thus achieving a voltage reduction process. The resulting second switched capacitor circuit can be used in the charging circuit module 133 of the second terminal device, or, when the first terminal device 110 is the receiving end, can also be used in the forward charging process of the charging circuit module 113 of the first terminal device.

[0098] (b) in Figure 5 shows another first switched capacitor circuit, which is composed of 16 transistors 521 to 536 and six second capacitors 540 to 545. In the first switched capacitor circuit shown in (b) in Figure 5, a ratio of output voltage to input voltage of 4:1 can be achieved. The principle will not be repeated here. Similarly, when the input terminal VIN and the output terminal VOUT in (b) in Figure 5 are swapped and the type of transistor is replaced, a ratio of output voltage to input voltage of 1:4 can be achieved. The second switched capacitor circuit obtained at this time can be used for the charging circuit module 133 in the second terminal device. Moreover, the first switched capacitor circuit shown in (b) in Figure 5 can also achieve a 1:2 boost or a 2:1 buck by keeping some transistors in the off state.

[0099] Similarly, if the input terminal VIN and the output terminal VOUT in FIG5(b) are swapped, a ratio of the output voltage to the input voltage of 1:4 can be achieved, thus achieving a step-down process. The resulting second switched capacitor circuit can be used in the charging circuit module 133 of the second terminal device, or, when the first terminal device 110 is the receiving end, can also be used in the forward charging process of the charging circuit module 113 of the first terminal device.

[0100] It is worth noting that FIG5 is only an example of the first switched capacitor circuit. The first switched capacitor circuit may further include more transistors and capacitors to achieve a 1:2N voltage boost, where N is any positive integer.

[0101] Optionally, in addition to the first switched capacitor circuit shown in Figure 5, the charging circuit module may also include a driving circuit for the first switched capacitor circuit, for example, controlling multiple sub-charge pump circuits through a control module to achieve soft start of the first switched capacitor circuit with a 1:2 boost or a 1:4 boost.

[0102] It should be noted that in the embodiment of the present application, all transistors in FIG5 are preferably MOS tubes. In other embodiments, the transistors can also be replaced by other switching elements, such as insulated gate bipolar transistor (IGBT) devices, integrated gate commutated thyristor (IGCT) devices, turn-off thyristor (GTO) devices, silicon controlled rectifier (SCR) devices, junction gate field effect transistor (JFET) devices, MOS controlled thyristor (MCT) devices, gallium nitride (GaN)-based power devices, silicon carbide (SiC)-based power devices, etc. The embodiment of the present application is not limited to this.

[0103] Optionally, in an embodiment of the present application, the boost ratio of the first switched capacitor circuit and the step-down ratio of the second switched capacitor circuit can be determined based on the battery power of the first terminal device or the battery power of the second terminal device to be charged. For example, when the power of the first terminal device is insufficient, the present application can increase the boost ratio of the first switched capacitor circuit, such as from 1:2 to 1:4, so that the second terminal device can obtain as much charging power as possible. For another example, when the power of the second terminal device is lower than the first power threshold, such as 10%, the boost ratio of the first switched capacitor circuit can be 1:4 or even higher, so that the charging power provided by the first terminal device is higher and the charging speed of the second terminal device is faster. Then, during the charging process of the second terminal device, when the power gradually increases, for example, to 50%, the boost ratio of the first switched capacitor circuit can be reduced, for example, to 1:3. When the power rises to 70%, the boost ratio of the first switched capacitor circuit can be further reduced to 1:2. By continuously adjusting the second output voltage and charging power, although the charging speed is slowed down, the rechargeable battery of the second terminal device can be protected to a certain extent.

[0104] Optionally, the reverse charging process of the first terminal device to the second terminal device can set multiple charging gears. Exemplarily, the electric energy obtained by the first switching capacitor circuit from the battery can vary according to the battery power of the first terminal device. For example, the first terminal device can set gears such as 9V / 2A (100%), 8.4V / 2A (80%), and 8.2V / 2A (65%). When the battery power of the first terminal device is 100%, the output voltage of the battery is 4.5V, and the first switching capacitor circuit can increase the output voltage of the battery by 2 times to 9V to output it to the second terminal device. Similarly, when the battery power of the first terminal device is 80%, the output voltage of the battery is 4.2V, and the first switching capacitor circuit can increase the output voltage of the battery by 2 times to 8.4V to output it to the second terminal device.

[0105] According to the above, when the input end and the output end shown in FIG5 are interchanged, the switching between step-down and step-up of the first switched capacitor circuit, or the switching between forward charging and reverse charging, can be achieved. In an embodiment of the present application, the method for achieving the switching between forward charging and reverse charging can be to achieve the switching between step-down and step-up through the same first switched capacitor circuit, or to set a first switched capacitor circuit and a first integrated circuit for forward charging, and then achieve the switching between forward charging and reverse charging by switching the two charging circuits.

[0106] For example, Figure 6 shows a schematic block diagram of a terminal device that implements switching between buck and boost of the same first switched capacitor circuit. As shown in Figure 6, the terminal device includes a mode switching control circuit 600, which is connected to other modules. The mode switching control circuit 600 is used to detect the operating mode or operating parameters of the first terminal device and determine whether the operating mode of the first switched capacitor circuit is forward charging or reverse charging based on the detection results.

[0107] For example, if the control module 111 detects that the user has selected the forward charging mode, or detects that the input terminal is connected to an external power supply such as a charger, the control module 111 sends a signal to the mode switching control circuit 600 to prompt the first terminal device to be in the forward charging mode and control the battery to be in the charging state. At this time, the mode switching control circuit 600 uses the external power supply connected to the wired charging interface as the input terminal of the charging circuit module 113 and the battery 114 as the output terminal of the charging circuit module 113, so that the charging circuit module or the first switched capacitor circuit in this application is in the step-down mode, and the supply voltage of the external power supply is stepped down and provided to the battery.

[0108] For another example, if the reverse charging mode operation selected by the user as shown in FIG2 is detected, or if it is detected that the wired charging interface at the input end is connected to an OTG-connected slave device, the control module 111 sends a signal to the mode switching control circuit 600 to prompt the first terminal device to be in the reverse charging mode and control the battery to be in the discharge state. At this time, the mode switching control circuit 600 uses the battery 114 as the input end of the charging circuit module 113 and the external power supply or slave device connected to the wired charging interface as the output end of the charging circuit module 113, so that the charging circuit module or the first switched capacitor circuit in this application is in the boost mode and the battery supply voltage is boosted and provided to the slave device.

[0109] Optionally, in an embodiment of the present application, the first switched capacitor circuit and the first control circuit in FIG. 5 and the mode switching control circuit in FIG. 6 can be integrated into the same switched capacitor chip, i.e., the charging circuit module is a switched capacitor chip. In other words, by switching the mode in the mode switching control circuit in the switched capacitor chip, the switching between the forward charging and reverse charging operating modes of the switched capacitor chip is achieved.

[0110] For example, FIG7 shows a schematic diagram of a charging circuit 700 that implements reverse charging and forward charging through different charging circuits. The charging circuit 700 includes a first switched capacitor circuit, a first integrated circuit, and a first charging switching circuit. The direction in FIG7 indicates the direction of charging, i.e., the first switched capacitor circuit is used for reverse charging, and the first integrated circuit is used for forward charging of the first terminal device or battery. The first integrated circuit and the first switched capacitor circuit are connected in parallel between the battery and the wired charging interface. When reverse charging is required, the control module 111 controls the switches and other components in the first charging switching circuit to make the first integrated circuit open and the first switched capacitor circuit open. Similarly, when forward charging is required, the control module 111 controls the switches and other components in the first charging switching circuit to make the first integrated circuit open and the first switched capacitor circuit open. In an embodiment of the present application, the first integrated circuit can be a buck circuit or a switched capacitor circuit, a switched capacitor chip, etc. for achieving step-down.

[0111] Optionally, in an embodiment of the present application, the first switched capacitor circuit and the first control circuit in FIG5 and the first integrated circuit and the first charging switching circuit in FIG7 can be integrated into the same switched capacitor chip, that is, the charging circuit module 113 is a switched capacitor chip. In other words, by switching the switching element in the charging switching circuit, the switching between the forward charging and reverse charging operating modes of the switched capacitor chip is achieved.

[0112] In an embodiment of the present application, the first terminal device and the second terminal device may further include a reverse charging protocol module to determine the reverse charging protocol that matches the first terminal device and the second terminal device. For example, the control module in the first terminal device is connected to the reverse charging protocol module, and when the wired charging interface of the first terminal device is connected to the second terminal device through the OTG data cable, the control module obtains the first reverse charging protocol determined by the reverse charging protocol module. When the control module in the second terminal device determines that the reverse charging protocol module of the second terminal device also supports the first reverse charging protocol, the first terminal device and the second terminal device can establish a connection to achieve reverse charging. When the reverse charging protocol module of the second terminal device does not support the first reverse charging protocol, the first terminal device and the second terminal device can achieve reverse charging through other reverse charging protocols. The reverse charging protocol can be a private fast charging QC (quick charge) protocol or a universal BC (battery charging) protocol, PD (power deliver) protocol, etc., wherein the charging voltage or charging power of the QC protocol and the PD protocol is greater than the charging voltage (such as the 5V mentioned above) or charging power of the BC protocol.

[0113] Exemplarily, the first charging protocol may be the above-mentioned QC protocol and PD protocol, etc., and the second charging protocol may be a BC protocol whose charging power or charging voltage is less than the first charging protocol. At this time, the reverse charging protocol module in the first terminal device may send a handshake protocol to the reverse charging protocol module of the second terminal device. If the response information of the reverse charging protocol module of the second terminal device is that it supports the first charging protocol, it can request the high-power and high-efficiency reverse charging method in the embodiment of the present application, and determine that the first terminal device and the second terminal device are charged through the first charging protocol, that is, the first terminal device and / or the second terminal device can achieve high-power and high-efficiency reverse charging through the charging circuit module or the switching capacitor chip shown in Figure 4 or Figure 5. If the response information of the reverse charging protocol module of the second terminal device is that it does not support the first charging protocol, it is determined that the first terminal device and the second terminal device are charged through the second charging protocol. At this time, the first terminal device and the second terminal device can achieve reverse charging through the original boost / buck circuit.

[0114] For ease of understanding, Figure 8 shows a schematic diagram of a terminal device handshake implemented through a reverse charging protocol, where the first terminal device is a reverse charging terminal (Source) providing power and the second terminal device is a receiving terminal (Sink) receiving power as an example.

[0115] As shown in Figure 8, first, the first terminal device can inform the second terminal device of its ability to provide power through the PD protocol or a private protocol, for example, by sending Source_cap to the second terminal device through the PD protocol. For example, the capability of the first terminal device can be the 9V / 2A (100%), 8.4V / 2A (80%), 8.2V / 2A (65%) and other gears of the first terminal device mentioned above. In other words, when the battery power of the first terminal device is 100%, the first terminal device will inform the second terminal device that the reverse charging capability it can provide is 9V / 2A.

[0116] Secondly, after receiving the capabilities provided by the first terminal device, the second terminal device will request reverse charging from the first terminal device in combination with its own hardware requirements and charging capabilities. For example, if the second terminal device has the above-mentioned second switched capacitor circuit, the second terminal device supports the 9V / 2A reverse charging capability provided by the first terminal device, and then sends Good_crc to the first terminal device and requests 9V / 2A reverse charging. For another example, if the second terminal device has the above-mentioned second switched capacitor circuit and the power is 80%, the second terminal device supports the 8.4V / 2A reverse charging capability provided by the first terminal device, and then sends Good_crc to the first terminal device and requests 8.4V / 2A reverse charging. For another example, if the second terminal device only has a boost / buck charging circuit, that is, the second terminal device only supports 5V / 1.5A reverse charging capability, the second terminal device sends Good_crc to the first terminal device (which can be used to determine whether the terminal device at the other end has received data information) and requests 5V / 1.5A reverse charging.

[0117] Then, the first terminal device may accept the request of the second terminal device by issuing Good_crc or accept, and adjust the power supply to the reverse charging capability that the second terminal device can accept, and issue Ps_rdy. For example, when the second terminal device is capable of receiving the 9V / 2A reverse charging capability provided by the first terminal device, the first terminal device may adjust the power supply to 9V / 2A, that is, perform reverse charging through a switched capacitor circuit. For another example, when the second terminal device is capable of receiving the 5V / 1.5A reverse charging capability provided by the first terminal device, the first terminal device may adjust the power supply to 5V / 1.5A, that is, perform reverse charging through a boost / buck circuit.

[0118] Finally, the second terminal device sends Good_crc, turns on its internal charging circuit, and receives the power provided by the first terminal device to realize charging.

[0119] It is worth noting that Figure 8 uses the PD protocol as an example to illustrate the handshake process between the reverse charging end and the receiving end. This is only an example. The present application can also implement the handshake process through a proprietary protocol or other reverse charging protocols mentioned above. The present application does not impose any restrictions on the choice of reverse charging protocol.

[0120] In an embodiment of the present application, in the case where the response information of the reverse charging protocol module of the second terminal device has not yet been received, the boost circuit included in the first terminal device can be used to reverse charge the second terminal device in advance. Figure 9 shows a schematic block diagram of a charging circuit 800. As shown in (a) of Figure 9, the charging circuit 800 includes the first switching capacitor circuit, the first boost circuit and the second charging switching circuit shown in Figure 5. While waiting for the response information of the reverse charging protocol module of the second terminal device, the second terminal device can be reversely charged in advance through the first boost circuit, until the response information is received that the reverse charging protocol module of the second terminal device supports the first charging protocol or the charging voltage of the second terminal device supports the second output voltage in step 420, the charging branch originally including the first boost circuit can be switched to the charging branch including the first switching capacitor circuit through the second charging switching circuit shown in (a) of Figure 9.

[0121] Optionally, since the voltage difference across the first boost circuit suddenly increases to the voltage difference of the first switched capacitor circuit during the process of switching the original charging branch including the first boost circuit to the charging branch including the first switched capacitor circuit, the boost circuit is at risk of burning. Therefore, as shown in (b) of Figure 9, in an embodiment of the present application, the charging branch including the first boost circuit is also provided with a boost protection circuit, and when the first terminal device switches from using the first boost circuit for reverse charging to using the first switched capacitor circuit for reverse charging, the boost protection circuit is used to protect the first Boost circuit during the switching process. The boost protection circuit may include any one or more of a metal oxide semiconductor field effect transistor (MOS) tube, a diode, a transistor, and a resistor. For example, the boost protection circuit may be an overvoltage protection (OVP) circuit or a transient voltage suppressor (TVS) protection circuit.

[0122] For example, FIG10 shows a schematic diagram of a boost protection circuit for a first boost circuit, wherein FIG10 shows a load switch, which can be used to turn off or on the boost / buck circuit.

[0123] As shown in FIG10 , the load switch for the first boost circuit may include an overvoltage protection (OVP) circuit, a reverse blocking circuit, an undervoltage lockout circuit, an over-temperature protection circuit, a reference circuit, and a current limit control circuit for boost protection. The VIN terminal of the load switch may be connected to the output terminal of the first boost circuit, and the VOUT terminal may be connected to the VBUS terminal. The load switch allows the 5V voltage output by the first boost circuit to be output to the VBUS port after the voltage is boosted. When the first switched capacitor circuit is used for reverse charging, the load switch can prevent backflow caused by the 9V voltage output by the first switched capacitor circuit.

[0124] The reverse blocking circuit may be formed by using two MOS tubes connected in series head-to-head to form a bidirectional switch, that is, both ends of the reverse blocking circuit can be turned off.

[0125] Specifically, for the load switch shown in Figure 10, when the voltage of VOUT is the above-mentioned 9V or any voltage value higher than the set comparison voltage (such as 5.5V), the gate voltage of the PMOS tube of the reverse blocking circuit shown in Figure 10 is always set high, and the PMOS tube is not turned on. In other words, whether in the direction from VIN to VOUT or in the direction from VOUT to VIN, the circuit is not turned on, and there is no leakage, that is, there is no forward output and reverse input. When the voltage of VOUT is any voltage value less than the set comparison voltage (such as 5.5V), the gate of the PMOS tube of the reverse blocking circuit will be pulled to the ground level, at which time the PMOS tube is turned on and the voltage of VOUT can be output normally. Therefore, the load switch shown in Figure 10 can be used to protect the above-mentioned boost / buck circuit to prevent backflow caused by the high voltage output of the first switch capacitor circuit.

[0126] Among them, the comparison voltage mentioned above can be the amplifier circuit in the circuit shown in Figure 10 or the reference voltage set by the comparison amplifier circuit, and the overvoltage protection circuit can detect the voltage of VOUT and input it to the amplifier circuit for comparison with the comparison voltage or the reference voltage, thereby controlling the on and off of the PMOS tube connected to the reverse blocking circuit.

[0127] Table 1 shows the results of a charging experiment provided by an embodiment of the present application. In this charging experiment, the same terminal device, or the second terminal device shown in FIG1 , is charged using different charging methods to obtain a comparison of charging speeds using different charging methods.

[0128] Table 1

[0129] As shown in Table 1, while the charging speed of the reverse charging method of the present application is slower than that of the forward charging method at 20 and 30 minutes, the charging speed is comparable at 10 minutes. Compared to existing low-power reverse charging methods and shared power banks, the reverse charging method of the present application is faster. At 10 minutes, the charging speed is increased by 150% compared to existing reverse charging methods. Furthermore, the total conversion efficiency of the charging circuit of the reverse charging method of the present application is higher, increasing by 6%, resulting in a 6% reduction in charging capacity.

[0130] FIG11 shows a schematic diagram of a terminal device 1100 provided in an embodiment of the present application.

[0131] In some embodiments, the terminal device 1100 includes: a battery 1110; a wired charging interface 1120, which is connected to another terminal device via an OTG data line; a first switching capacitor circuit 1130, which is electrically connected between the battery and the wired charging interface; a control module 1140, which is used to determine that the terminal device is the main device for providing power in the OTG connection in response to the reverse charging mode of the terminal device selected by the user, and control the first switching capacitor circuit to increase the first output voltage of the battery to a second output voltage, and output the second output voltage to the wired charging interface for transmission to the other terminal device via the OTG data line.

[0132] In the embodiment of the present application, the control module 1140 may be an electronic operation processor. The specific functions and beneficial effects of the control module 1140 are described in the above embodiment and will not be repeated here for the sake of brevity.

[0133] Figure 12 is a schematic block diagram of a terminal device 1200 provided in an embodiment of the present application. As shown in Figure 12, the terminal device 1200 includes at least one processor 1220. The processor 1220 is coupled to a memory and is configured to execute instructions stored in the memory to transmit and / or receive signals. Optionally, the device 1200 also includes a memory 1230 for storing instructions. Optionally, the device 1200 also includes a transceiver 1210, and the processor 1220 controls the transceiver 1210 to transmit and / or receive signals.

[0134] It should be understood that the processor 1220 and memory 1230 may be combined into a processing device, and the processor 1220 is configured to execute program codes stored in the memory 1230 to implement the above functions. In specific implementations, the memory 1230 may also be integrated into the processor 1220 or independent of the processor 1220.

[0135] It should also be understood that the transceiver 1210 may include a transceiver (or receiver) and a transmitter (or transmitter). The transceiver may further include an antenna, and the number of antennas may be one or more. The transceiver 1210 may also be a communication interface or interface circuit.

[0136] During implementation, each step of the above method can be completed by an integrated logic circuit of the hardware in the processor or by instructions in the form of software. The steps of the method disclosed in conjunction with the embodiments of the present application can be directly embodied as being executed by a hardware processor, or can be executed by a combination of hardware and software modules in the processor. The software module can be located in a storage medium mature in the art such as a random access memory, a flash memory, a read-only memory, a programmable read-only memory or an electrically erasable programmable memory, a register, etc. The storage medium is located in the memory, and the processor reads the information in the memory and completes the steps of the above method in conjunction with its hardware. To avoid repetition, it will not be described in detail here.

[0137] It should be noted that the processor in the embodiments of the present application can be an integrated circuit chip with signal processing capabilities. During implementation, each step of the above method embodiment can be completed by hardware integrated logic circuits in the processor or software instructions. The above processor can be a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components. The various methods, steps, and logic block diagrams disclosed in the embodiments of the present application can be implemented or executed. The general-purpose processor can be a microprocessor or any conventional processor. The steps of the method disclosed in the embodiments of the present application can be directly implemented and executed by a hardware decoding processor, or by a combination of hardware and software modules in the decoding processor. The software module can be located in a storage medium mature in the art, such as random access memory, flash memory, read-only memory, programmable read-only memory, electrically erasable programmable memory, registers, etc. The storage medium is located in the memory, and the processor reads the information in the memory and completes the steps of the above method in combination with its hardware.

[0138] It is understood that the memory in the embodiments of the present application may be a volatile memory or a non-volatile memory, or may include both volatile and non-volatile memories. Among them, the non-volatile memory may be a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), or a flash memory. The volatile memory may be a random access memory (RAM), which is used as an external cache. By way of example and not limitation, many forms of RAM are available, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate synchronous DRAM (DDR SDRAM), enhanced SDRAM (ESDRAM), synchronous-link DRAM (SLDRAM), and direct RAM-bus RAM (DR RAM). It should be noted that the memory of the systems and methods described herein is intended to include, but is not limited to, these and any other suitable types of memory.

[0139] According to the charging method provided in the embodiment of the present application, the present application also provides a computer program product, which stores computer program code. When the computer program code is run on a computer, the computer executes the charging method of the present application.

[0140] According to the charging method provided in an embodiment of the present application, the present application also provides a computer-readable medium, which stores a program code. When the program code is run on a computer, the computer executes the charging method of the present application.

[0141] According to the charging method provided in the embodiment of the present application, the present application also provides a system, which includes the aforementioned device or equipment.

[0142] In the above embodiments, all or part of the embodiments may be implemented by software, hardware, firmware, or any combination thereof. When implemented using software, all or part of the embodiments may be implemented in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer instructions are loaded and executed on a computer, all or part of the processes or functions described in the embodiments of the present application are generated. The computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions may be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions may be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via a wired (e.g., coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) method. The computer-readable storage medium may be any available medium that a computer can access or a data storage device such as a server or data center that includes one or more available media integrated therein. The available medium may be a magnetic medium (eg, a floppy disk, a hard disk, a magnetic tape), an optical medium (eg, a high-density digital video disc (DVD)), or a semiconductor medium (eg, a solid state disc (SSD)).

[0143] The network-side devices in the above-mentioned various apparatus embodiments correspond to the network-side devices or terminal devices in the terminal devices and method embodiments, and the corresponding steps are performed by the corresponding modules or units. For example, the communication unit (transceiver) performs the steps of obtaining or sending in the method embodiments, and other steps except sending and obtaining can be performed by the processing unit (processor). The functions of the specific units can be referred to the corresponding method embodiments. Among them, there can be one or more processors.

[0144] As used in this specification, the terms "component," "module," "system," and the like are used to refer to computer-related entities, hardware, firmware, a combination of hardware and software, software, or software in execution. For example, a component can be, but is not limited to, a process running on a processor, a processor, an object, an executable file, an execution thread, a program, and / or a computer. By way of illustration, both an application running on a computing device and a computing device can be a component. One or more components can reside in a process and / or an execution thread, and a component can be located on a computer and / or distributed between two or more computers. In addition, these components can be executed from various computer-readable media having various data structures stored thereon. Components can communicate, for example, via local and / or remote processes based on signals having one or more data packets (e.g., data from two components interacting with another component on a local system, a distributed system, and / or a network, such as the Internet interacting with other systems via signals).

[0145] The terms "including," "having," and any variations thereof in the specification and claims of this application and the accompanying drawings are intended to cover non-exclusive inclusions. The terms "first," "second," and the like in the specification and claims of this application and the accompanying drawings are used to distinguish between different items, not to describe a specific order or a primary-secondary relationship.

[0146] It should be understood that the term "and / or" as used herein simply describes an association between related objects, indicating that three possible relationships exist. For example, "A and / or B" can represent: A alone, A and B together, or B alone. A and B can be singular or plural. Furthermore, the character " / " as used herein generally indicates an "or" relationship between the preceding and following related objects, but it may also indicate an "and / or" relationship. For specific understanding, please refer to the context.

[0147] It should be understood that in the various embodiments of the present application, the size of the serial numbers of the above-mentioned processes does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0148] Those skilled in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0149] Those skilled in the art will clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0150] In the several embodiments provided in this application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are merely schematic. For example, the division of the units is merely a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0151] The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of these units may be selected to achieve the purpose of this embodiment according to actual needs.

[0152] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0153] If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art, or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes several instructions for enabling a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.

[0154] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of this application. Therefore, the scope of protection of this application should be based on the scope of protection of the claims.

Claims

1. A charging method, characterized in that: The method is applied to a first terminal device charging a second terminal device, the first terminal device comprising a battery, a first switch capacitor circuit and a wired charging interface, the first switch capacitor circuit being electrically connected between the battery and the wired charging interface, the wired charging interface being connected to the second terminal device via an OTG data line, the method comprising: In response to a reverse charging mode of the first terminal device selected by a user, determining that the first terminal device is a main device for providing power in the OTG connection; The first switch capacitor circuit is controlled to increase the first output voltage of the battery to a second output voltage, and the second output voltage is output to the wired charging interface to be transmitted to the second terminal device through the OTG data line.

2. The method according to claim 1, characterized in that The first switched capacitor circuit includes a charge pump circuit, and the first terminal device further includes a first control circuit, and the first control circuit is used to control the on-off state of one or more transistors in the charge pump circuit.

3. The method according to claim 1 or 2, characterized in that: The first terminal device further includes a mode switching control circuit, the mode switching control circuit is used to switch the working mode of the first switch capacitor circuit, the working mode of the first switch capacitor circuit includes a buck mode or a boost mode, in the buck mode, the output end of the first switch capacitor circuit is the battery to realize forward charging, in the boost mode, the input end of the first switch capacitor circuit is the battery to realize reverse charging, and controlling the first switch capacitor circuit to increase the first output voltage of the battery to the second output voltage includes: Determining that the working state of the battery is a discharge state; The mode switching control circuit is controlled to determine that the input end of the first switch capacitor circuit is the battery and the output end is the wired charging interface, so that the first switch capacitor circuit is switched from the buck mode to the boost mode to increase the first output voltage of the battery to the second output voltage.

4. The method according to claim 3, characterized in that The mode switching control circuit and the first switch capacitor circuit are integrated in a first switch capacitor chip, and controlling the mode switching control circuit so that the first switch capacitor circuit switches from the buck mode to the boost mode includes: The mode switching control circuit in the first switch capacitor chip is controlled so that the working mode of the first switch capacitor chip is switched from the forward charging mode to the reverse charging mode. When the first switch capacitor chip is in the forward charging mode, the first switch capacitor circuit is in the buck mode. When the first switch capacitor chip is in the reverse charging mode, the first switch capacitor circuit is in the boost mode.

5. The method according to claim 1 or 2, characterized in that: The first terminal device is further provided with a first charging switching circuit and a first integrated circuit, the first integrated circuit and the first switching capacitor circuit are connected in parallel between the battery and the wired charging interface, the first charging switching circuit is used to turn on one of the first integrated circuit and the first switching capacitor circuit and turn off the other, the first integrated circuit is used to positively charge the first terminal device, and after determining that the first terminal device is a master device for providing power in the OTG connection, the method further includes: The first charging switching circuit is controlled to turn off the first integrated circuit and turn on the first switch capacitor circuit, so that the first terminal device switches from using the first integrated circuit for forward charging to using the first switch capacitor circuit for reverse charging.

6. The method according to any one of claims 1 to 5, characterized in that: The first terminal device is further provided with a first step-up chopper boost circuit, the first boost circuit and the first switch capacitor circuit are connected in parallel between the battery and the wired charging interface, and the first switch capacitor circuit is controlled to increase the first output voltage of the battery to the second output voltage. The method also includes: Controlling the first boost circuit to increase the first output voltage to a third output voltage, and outputting the third output voltage to the wired charging interface, wherein the third output voltage is lower than the second output voltage; The controlling the first switch capacitor circuit to increase the first output voltage of the battery to a second output voltage comprises: When it is determined that the charging voltage supported by the second terminal device is the second output voltage, the first switch capacitor circuit is controlled to increase the first output voltage of the battery to the second output voltage.

7. The method according to claim 6, characterized in that The first boost circuit is provided with a boost protection circuit. When the first terminal device switches from using the first boost circuit for reverse charging to using the first switched capacitor circuit for reverse charging, the boost protection circuit is used to protect the first boost circuit during the switching process.

8. The method according to claim 7, characterized in that The boost protection circuit includes any one or more of a metal oxide semiconductor field effect transistor (MOS) tube, a diode, a triode, and a resistor.

9. The method according to any one of claims 1 to 8, characterized in that The ratio of the second output voltage to the first output voltage is any one or more of 4:1, 3:1 and 2:

1.

10. The method according to any one of claims 1 to 9, characterized in that The first terminal device identifies the second terminal device through any one or several charging protocols including the power transmission PD protocol, the fast charging QC protocol, and the battery charging BC protocol.

11. The method according to any one of claims 1 to 10, characterized in that The method further comprises: Obtaining power information of the first terminal device or the second terminal device; The second output voltage is determined according to the power information of the first terminal device or the second terminal device.

12. A terminal device, characterized in that: The terminal device comprises: Battery; A wired charging interface, which is connected to another terminal device via an OTG data cable; a first switch capacitor circuit, wherein the first switch capacitor circuit is electrically connected between the battery and the wired charging interface; A control module is used to determine that the first terminal device is a main device for providing power in the OTG connection in response to the reverse charging mode of the first terminal device selected by the user, and control the first switch capacitor circuit to increase the first output voltage of the battery to a second output voltage, and output the second output voltage to the wired charging interface for transmission to the other terminal device through the OTG data line.

13. The terminal device according to claim 12, characterized in that: The first switch capacitor circuit includes a charge pump circuit, and the control module includes a first control circuit, which is used to control the on-off state of one or more transistors in the charge pump circuit.

14. The terminal device according to claim 12 or 13, characterized in that: The terminal device further includes: a mode switching control circuit, wherein the mode switching control circuit is used to switch the working mode of the first switch capacitor circuit, wherein the working mode of the first switch capacitor circuit includes a buck mode or a boost mode, wherein in the buck mode, the first switch capacitor circuit is used to output a supply voltage to the battery to achieve forward charging, and in the boost mode, the first switch capacitor circuit is used to receive a supply voltage from the battery to achieve reverse charging; The control module is specifically used for: Determining that the working state of the battery is a discharge state; The mode switching control circuit is controlled to determine that the input end of the first switch capacitor circuit is the battery and the output end is the wired charging interface, so that the first switch capacitor circuit is switched from the buck mode to the boost mode to increase the first output voltage of the battery to the second output voltage.

15. The terminal device according to claim 14, characterized in that: The terminal device comprises: A first switched capacitor chip, wherein the first switched capacitor chip comprises the first switched capacitor circuit and the mode switching control circuit; The control module is specifically used for: By controlling the mode switching control circuit in the first switch capacitor chip, the working mode of the first switch capacitor chip is switched from the forward charging mode to the reverse charging mode, so that the first switch capacitor chip increases the first output voltage of the battery to the second output voltage. When the first switch capacitor chip is in the forward charging mode, the first switch capacitor circuit is in the buck mode, and when the first switch capacitor chip is in the reverse charging mode, the first switch capacitor circuit is in the boost mode.

16. The terminal device according to claim 12 or 13, characterized in that: The terminal device further includes: a first integrated circuit, wherein the first integrated circuit and the first switched capacitor circuit are connected in parallel between the battery and the wired charging interface, and the first integrated circuit is used to positively charge the first terminal device; a first charging switching circuit, the first charging switching circuit being used to conduct one of the first integrated circuit and the first switched capacitor circuit; The control module is also used for: The first charging switching circuit is controlled to turn off the first integrated circuit and turn on the first switch capacitor circuit, so that the first terminal device switches from using the first integrated circuit for forward charging to using the first switch capacitor circuit for reverse charging.

17. The terminal device according to any one of claims 12 to 16, characterized in that: The terminal device further includes: A first step-up chopper boost circuit, wherein the first boost circuit and the first switch capacitor circuit are connected in parallel between the battery and the wired charging interface; Before the control module controls the first switch capacitor circuit to increase the first output voltage of the battery to the second output voltage, The control module is also used for: Controlling the first boost circuit to increase the first output voltage to a third output voltage, and outputting the third output voltage to the wired charging interface, wherein the third output voltage is lower than the second output voltage; The control module is specifically used for: When it is determined that the charging voltage supported by the other terminal device is the second output voltage, the first switch capacitor circuit is controlled to increase the first output voltage of the battery to the second output voltage.

18. The terminal device according to claim 17, characterized in that: The first boost circuit is provided with a boost protection circuit. When the terminal device switches from using the first boost circuit for reverse charging to using the first switched capacitor circuit for reverse charging, the boost protection circuit is used to protect the first boost circuit during the switching process.

19. The terminal device according to claim 18, characterized in that: The boost protection circuit includes any one or more of a metal oxide semiconductor field effect transistor (MOS) tube, a diode, a triode, and a resistor.

20. The terminal device according to any one of claims 12 to 19, characterized in that: The ratio of the second output voltage to the first output voltage is any one or more of 4:1, 3:1 and 2:

1.

21. The terminal device according to any one of claims 12 to 20, characterized in that: The terminal device identifies the other terminal device through any one or several charging protocols including the power transmission PD protocol, the fast charging QC protocol, and the battery charging BC protocol.

22. The terminal device according to any one of claims 12 to 21, characterized in that: The control module is further used to: obtain power information of the terminal device or the other terminal device, and determine the second output voltage according to the power information of the terminal device or the other terminal device.

23. A terminal device, characterized in that: include: A processor, a memory and a transceiver, wherein the memory is used to store a computer program, and the processor is used to call and run the computer program stored in the memory to execute the method according to any one of claims 1 to 11.

24. A chip, characterized in that: The chip includes at least one processor. When program instructions are executed by the at least one processor, the method according to any one of claims 1 to 11 is executed.

25. A computer-readable storage medium, characterized in that: Instructions are stored thereon, and when the instructions are executed on a computer, the computer is caused to execute the method according to any one of claims 1 to 11.

26. A computer program product, characterized in that The method comprises computer program instructions which cause a computer to execute the method according to any one of claims 1 to 11.

Images