CN118381205A

CN118381205A - Wireless transmitting chip, wireless charging circuit, electronic equipment and system

Info

Publication number: CN118381205A
Application number: CN202410579856.2A
Authority: CN
Inventors: 武渊
Original assignee: Honor Device Co Ltd
Current assignee: Honor Device Co Ltd
Priority date: 2024-05-11
Filing date: 2024-05-11
Publication date: 2024-07-23

Abstract

The present application provides a wireless transmitting chip, a wireless charging circuit, an electronic device and a system, which can save the circuit board area. The circuit includes: a second transmitting coil; a wireless transmitting chip, including a processing circuit, a first MOS switch and a second MOS switch; wherein the processing circuit is used to obtain the battery voltage of the first electronic device and generate an AC voltage according to the battery voltage; the processing circuit is connected to the first transmitting coil through the first MOS switch, and the processing circuit is connected to the second transmitting coil through the second MOS switch; wherein, when the first MOS switch is turned on and the second MOS switch is turned off, the first transmitting coil is used to wirelessly charge the second electronic device according to the AC voltage; when the second MOS switch is turned on and the first MOS switch is turned on, the second transmitting coil is used to wirelessly charge the third electronic device according to the AC voltage.

Description

Wireless transmitting chip, wireless charging circuit, electronic equipment and system

Technical Field

The present application relates to the field of electronic devices, and in particular, to a wireless transmitting chip, a wireless charging circuit, an electronic device, and a system.

Background

To enhance the user experience, some electronic devices are often used with other devices. For example, taking a tablet computer as an example, it may be equipped with various accessories, such as a wireless keyboard, an electronic stylus, etc., to make various forms of input to the tablet computer.

For ease of use, the electronic device may charge its accessories in a wireless charging manner. At present, wireless charging circuits of various electronic devices are disposed on a circuit board of the electronic device, however, along with the development of the electronic device towards a lighter and thinner direction, how to reduce the area of the circuit board becomes a problem to be solved.

Disclosure of Invention

In order to solve the technical problems, the application provides a wireless transmitting chip, a wireless charging circuit, electronic equipment and a system. The area of the circuit board can be reduced, and the light and thin property of the electronic equipment can be improved.

In a first aspect, the present application provides a wireless charging circuit, where the wireless charging circuit is applied to a first electronic device, the wireless charging circuit includes: a first transmitting coil; a second transmitting coil; and a wireless transmitting chip. The wireless transmitting chip comprises a processing circuit, a first MOS switch and a second MOS switch. The processing circuit is used for acquiring the battery voltage of the first electronic device and generating alternating current voltage according to the battery voltage. The processing circuit is connected with the first transmitting coil through the first MOS switch. And the processing circuit is connected with the second transmitting coil through a second MOS switch. Under the condition that the first MOS switch is on and the second MOS switch is off, the first transmitting coil is used for wirelessly charging the second electronic equipment according to the alternating voltage. And under the condition that the second MOS switch is conducted and the first MOS switch is conducted, the second transmitting coil is used for wirelessly charging the third electronic equipment according to the alternating voltage.

Through the wireless charging circuit, as the first PMOS tube Q11 and the second PMOS tube Q12 are integrated inside the TX chip, a discrete MOS tube does not need to be arranged outside the TX chip, a peripheral design circuit is simplified, and the area of a PCB (printed circuit board) does not need to be occupied. And the integration level of the circuit inside the TX chip is higher than that of the circuit on the PCB, so that the area of the PCB is reduced and the cost is saved.

By way of example, the electronic device may be a first electronic device that is wirelessly charged at a first power, i.e. an electronic device that is wirelessly charged at a low power. The first power is less than the second power compared to a second electronic device wirelessly charged at the second power. The first power may be, for example, 1-5 w. By way of example, the first electronic device may be an electronic device that wirelessly charges accessories, such as a tablet computer, a headset box, or the like.

Illustratively, the processing circuitry may include inverter circuitry 231. Alternatively, the inverter circuit may be an inverter full bridge formed by connecting a plurality of MOS switches.

Illustratively, the first transmit coil may be a first transmit coil L11 and the second transmit coil may be a second transmit coil L12. The first transmitting coil may be disposed corresponding to a first receiving coil in the second electronic device, and the second transmitting coil may be disposed corresponding to a second receiving coil in the third electronic device.

Specifically, one end of the first transmitting coil may be connected to the first output end of the processing circuit through the first capacitor, and the other end of the first transmitting coil may be connected to the second output end of the processing circuit through the first MOS switch. One end of the second transmitting coil can be connected with the first output end of the processing circuit through the second capacitor, and the other end of the second transmitting coil can be connected with the second output end of the processing circuit through the second MOS switch.

The first transmitting coil, the first capacitor and the first MOS switch may be disposed on the same wireless charging path (or referred to as a resonant circuit), where the first MOS switch is used to control on or off of the wireless charging path.

The second transmitting coil, the second capacitor and the second MOS switch may be disposed on the same wireless charging path (or referred to as a resonant circuit), where the second MOS switch is used to control on or off of the wireless charging path.

Illustratively, the first MOS switch and the second MOS switch may be the first PMOS transistor Q11 and the second PMOS transistor Q12, or the second MOS switch and the second MOS switch may be the first NMOS transistor Q31 and the second NMOS transistor Q32, respectively.

Illustratively, the wireless transmit chip may be a TX chip, such as TX chip 230.

The wireless charging circuit may further include a third transmitting coil, and the wireless transmitting chip may further include a third MOS switch, which is connected in a similar manner to the first MOS switch, and reference may be made to the description of the first MOS switch.

For example, the first transmitting coil, the second transmitting coil, and the wireless transmitting chip may be disposed on a PCB circuit board of the first electronic device.

For example, the first electronic device may take turns to wirelessly charge the second electronic device and the third electronic device. Accordingly, when the first MOS switch is on, the second MOS switch needs to be off. When the second MOS switch is on, the first MOS switch needs to be off.

The first MOS switch and the second MOS switch may be controlled by a first controller in the wireless transmitting chip or by a second controller in the first electronic device, external to the wireless transmitting chip, for example.

According to a first aspect, the first MOS switch and the second MOS switch are PMOS transistors.

The wireless transmitting chip comprises a first controller for: in a first control stage, outputting a first control signal to a control end of the first MOS switch so as to control the first MOS switch to be conducted; and in the second control stage, outputting a first control signal to the control end of the second MOS switch to control the second MOS switch to be turned on.

Therefore, the first controller can realize time-sharing charging control of the second electronic equipment and the third electronic equipment through the on-off process of the first MOS switch and the second MOS switch, and control accuracy of a one-to-two wireless charging scheme is improved. And because the first controller is integrated inside the wireless transmitting chip, the wireless transmitting chip can have wireless charging control capability of one driving two by means of other controllers.

The first controller may be an MCU, for example. The first control signal may be a low level signal, the first control signal having a first level value. The first level value is lower than or equal to the source voltage of the MOS switch, or the difference value between the first level value and the source voltage is smaller than a preset voltage threshold.

For example, the first electronic device may enter a first control phase when it is required to charge the second electronic device and enter a second control phase when it is required to charge the third electronic device. For example, the first electronic device may alternately enter a first control phase and a second control phase.

According to the first aspect, or any implementation manner of the first aspect, the first MOS switch and the second MOS switch are NMOS transistors; the wireless transmitting chip comprises a first controller and a bootstrap circuit, wherein the bootstrap circuit is used for increasing a first control signal output by the first controller from a first level value to a second level value; the first controller is used for: in the first control stage, outputting a first control signal of a second level value to a control end of the first MOS switch so as to control the first MOS switch to be conducted; and in the second control stage, outputting a first control signal of a second level value to a control end of the second MOS switch so as to control the second MOS switch to be conducted.

Therefore, the bootstrap circuit can generate the driving voltage required by the NMOS tube, and the area of the PCB can be further saved due to the volume of the PMOS tube of the NMOS tube.

The first controller may be an MCU inside the wireless transmission chip, for example. Alternatively, the MCU may control the inverter circuit.

The bootstrap circuit may be an original circuit of the wireless transmitting chip, for example, may be a bootstrap circuit for generating a control voltage of the MOS transistor in the inverter circuit, which is not limited. For example, the bootstrap circuit may be a bootstrap capacitor or the like, which is not limited thereto. In one example, if the first connection terminal of the NMOS transistor is applied with a voltage of 5V (the first level value), the bootstrap circuit may raise it to 10V, thereby controlling the NMOS transistor to be turned on.

According to the first aspect, or any implementation manner of the first aspect, the wireless charging circuit further includes a second controller, where the second controller is configured to obtain a first detection signal sent by the first detection sensor and obtain a second detection signal sent by the second detection sensor; and in response to the first detection signal and the second detection signal, sending a notification signal to the first controller in case that the first MOS switch is determined to be on, the notification signal being used for notifying the first controller to control the first MOS switch to be on; and sending a notification signal to the first controller when the second MOS switch is determined to be on, wherein the notification signal is used for notifying the first controller to control the second MOS switch to be on; the first detection signal indicates that the second electronic device is placed at a first preset position of the first electronic device, and the second detection signal indicates that the third electronic device is placed at a second preset position of the first electronic device.

In this way, the step that the second controller notifies the first controller can be added in the charging flow, so that the communication interaction between the first controller and the second controller can realize accurate control of the wireless charging flow.

The second controller may be an AP, for example. The AP controller may control the wireless charging process, such as the determination of gating policies, etc.

According to a first aspect, or any implementation manner of the first aspect, the wireless transmitting chip includes: the first output port is respectively connected with one end of the first transmitting coil and one end of the second transmitting coil, wherein the first output port is connected to the first output end of the processing circuit, and the second output end of the processing circuit is respectively connected with the first connecting end of the first MOS switch and the first connecting end of the second MOS switch; the second output port is connected with the other end of the first transmitting coil, and is connected to the second connecting end of the first MOS switch; and the third output port is connected with the other end of the second transmitting coil, wherein the third output port is connected to the second connecting end of the second MOS switch.

Thus, the wireless transmitting chip can realize the control of two wireless charging loops through three output ports, and the control precision and the control convenience are improved.

Illustratively, the first through third output ports may be first through third output ports AC1 through AC3, wherein the first output port AC1 is a common connection, and the second and third output ports AC2 and AC3 are non-common.

According to the first aspect, or any implementation manner of the first aspect, the wireless charging circuit further includes a second controller, where the second controller is configured to: in a first control stage, outputting a first control signal to a control end of the first MOS switch so as to control the first MOS switch to be conducted; and in the second control stage, outputting a first control signal to the control end of the second MOS switch to control the second MOS switch to be turned on.

Therefore, the whole charging process can be integrally controlled through the second controller, and the control convenience and accuracy are improved.

According to the first aspect, or any implementation manner of the first aspect, the wireless transmitting chip further includes: the first control port is connected with a first output end of the second controller, wherein the first control port is connected to a control end of the first MOS switch; and the second control port is connected with a second output end of the second controller, wherein the second control port is connected to a control end of the second MOS switch.

Therefore, through the first control port and the second control port, the second controller outside the wireless transmitting chip can control the MOS switch inside the wireless transmitting chip, so that the wireless transmitting chip and the external controller are matched for use to realize a one-to-two or one-to-many wireless charging control function.

The second controller may be, for example, a native controller in the first electronic device.

According to a first aspect, or any implementation manner of the first aspect, the first electronic device is configured to wirelessly charge the second electronic device and the third electronic device with a first power, where the first power is less than a preset power threshold.

Therefore, as the charging power of the high-power charged electronic equipment is larger, the switching tube can cause the problem of heating of the device due to the larger charging power, thereby influencing the safety and the service life of the equipment. In the high-power charged electronic equipment, the heating power of the MOS tube is often lower due to the fact that the impedance of the MOS tube is larger, so that a larger switch tube is selected in the high-power charged electronic equipment, and the heating problem of the MOS tube is reduced in a mode of reducing the impedance of the MOS tube. However, the larger MOS transistor cannot be integrated inside the TX chip, so the MOS transistor of the electronic device charged with high power needs to be disposed on the PCB circuit board, which occupies a larger circuit board area. In the embodiment of the application, the equipment such as the tablet personal computer is low-power charging equipment, and because the charging power is smaller, the heating problem of the MOS tube is less obvious, and therefore, the MOS tube has low impedance requirements, so that the MOS tube with smaller volume can be integrated in the TX chip in the low-power charging equipment, and the heat dissipation safety of the electronic equipment is ensured while the area of a PCB (printed circuit board) is reduced.

Illustratively, the preset power threshold is the charging power of a high power charging device such as a cell phone, a wireless charging dock, etc.

According to the first aspect, or any implementation manner of the first aspect, the value range of the first power is [1w,5w ].

In this way, the scheme provided by the embodiment of the application can be applied to low-power wireless charging equipment.

According to a first aspect, or any implementation manner of the first aspect, the second electronic device and the third electronic device are accessories of the first electronic device.

Like this, first electronic equipment can charge for a plurality of accessories are wireless, and a plurality of accessories need not to use the charger to charge respectively, also need not to change another accessory again and charge after electronic equipment is full of the electricity for one accessory, corresponds a plurality of accessories and first electronic equipment and places, and electronic equipment can initiatively charge to a plurality of accessories, has improved the convenience of charging.

According to a first aspect, or any implementation manner of the first aspect, in a case where the first electronic device includes a tablet computer, the second electronic device is an electronic stylus, and the third electronic device is a wireless keyboard.

Like this, can improve the use convenience and the convenience of charging of panel computer, and the battery of electronic handwriting pen and wireless keyboard is less, can compromise the security of charging when reducing PCB circuit board area with MOS pipe integration at wireless transmitting chip, improved user's use experience. And the light and thin property of the panel electric energy can be further improved, and the development and improvement direction of the panel computer are met.

And under the condition that the first electronic equipment comprises an earphone box, the second electronic equipment is a left earphone, and the third electronic equipment is a right earphone.

Therefore, the charging convenience of the wireless earphone can be improved, and the use experience of a user is improved. And the volume of the wireless earphone can be further improved, and the wireless earphone accords with the development and improvement direction of the wireless earphone.

In a second aspect, an embodiment of the present application provides a wireless charging circuit, where the wireless charging circuit is applied to a first electronic device. The wireless charging circuit includes: a first transmitting coil; a second transmitting coil; the first MOS switch is connected with the first transmitting coil; the second MOS switch is connected with the second transmitting coil, wherein the first MOS switch and the second MOS switch are NMOS tubes; and a wireless transmitting chip. The wireless transmitting chip comprises a processing circuit, a bootstrap circuit and a first controller; the processing circuit is used for acquiring the battery voltage of the first electronic equipment and generating alternating current voltage according to the battery voltage; the processing circuit is connected with the first transmitting coil through the first MOS switch, and the processing circuit is connected with the second transmitting coil through the second MOS switch. The bootstrap circuit is used for increasing the first control signal output by the first controller from a first level value to a second level value; the first controller is used for controlling the first MOS switch or the second MOS switch to be conducted by using a first control signal of a second level value. Under the condition that the first MOS switch is turned on and the second MOS switch is turned off, the first transmitting coil is used for wirelessly charging the second electronic equipment according to the alternating voltage; and under the condition that the second MOS switch is conducted and the first MOS switch is conducted, the second transmitting coil is used for wirelessly charging the third electronic equipment according to the alternating voltage.

Through the wireless charging circuit, the voltage of the second output can be raised to the driving voltage of the NMOS tube through a bootstrap circuit built in the wireless transmitting chip. The volume (or the size or the occupied area on the wireless transmitting chip) of the NMOS tube is smaller than that of the PMOS tube, so that the areas of the wireless transmitting chip and the PCB circuit board can be further reduced. Optionally, the bootstrap circuit may be an original bootstrap circuit in the wireless transmitting chip, so as to further improve the integration level of the wireless transmitting chip and ensure accurate control of the wireless transmitting chip on the charging process.

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

In a third aspect, an embodiment of the present application provides a wireless transmitting chip applied to a first electronic device, where the wireless transmitting chip includes: the processing circuit is used for acquiring the battery voltage of the first electronic device and generating alternating current voltage according to the battery voltage; the first MOS switch is connected with the processing circuit, and the second connecting end of the first MOS switch is used for being connected with a first transmitting coil of the first electronic equipment; the first connecting end of the second MOS switch is connected with the processing circuit, and the second connecting end of the second MOS switch is used for connecting a second transmitting coil of the first electronic equipment; under the condition that the first MOS switch is turned on and the second MOS switch is turned off, the first transmitting coil is used for wirelessly charging the second electronic equipment according to the alternating voltage; and under the condition that the second MOS switch is conducted and the first MOS switch is conducted, the second transmitting coil is used for wirelessly charging the third electronic equipment according to the alternating voltage.

According to a third aspect, the first MOS switch and the second MOS switch are PMOS transistors; the wireless transmitting chip comprises a first controller for: in a first control stage, outputting a first control signal to a control end of the first MOS switch so as to control the first MOS switch to be conducted; and in the second control stage, outputting a first control signal to the control end of the second MOS switch to control the second MOS switch to be turned on.

According to a third aspect, or any implementation manner of the above third aspect, the first MOS switch and the second MOS switch are NMOS transistors; the wireless transmitting chip comprises a first controller and a bootstrap circuit, wherein the bootstrap circuit is used for increasing a first control signal output by the first controller from a first level value to a second level value; the first controller is used for: in the first control stage, outputting a first control signal of a second level value to a control end of the first MOS switch so as to control the first MOS switch to be conducted; and in the second control stage, outputting a first control signal of a second level value to a control end of the second MOS switch so as to control the second MOS switch to be conducted.

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

In a fourth aspect, the present application provides an electronic device, including: the wireless charging circuit of the first aspect or any possible implementation of the first aspect or the wireless charging circuit of the second aspect or any possible implementation of the second aspect.

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

In a fifth aspect, the present application provides a wireless charging system comprising: a first electronic device comprising the wireless charging circuit of the first aspect or any possible implementation of the first aspect or the wireless charging circuit of the second aspect or any possible implementation of the second aspect. The second electronic device comprises a first receiving coil, a first charging control circuit and a first battery; the first receiving coil is arranged corresponding to the first transmitting coil and is used for receiving a first magnetic field signal transmitted by the first transmitting coil and generating first alternating current according to the first magnetic field signal; the first charging control circuit is used for charging the first battery according to the first alternating current. The third electronic device comprises a second receiving coil, a second charging control circuit and a second battery; the second receiving coil is arranged corresponding to the second transmitting coil and is used for receiving a second magnetic field signal sent by the second transmitting coil and generating second alternating current according to the second magnetic field signal; the second charging control circuit is used for charging the second battery according to the second alternating current.

According to a fifth aspect, the second electronic device and the third electronic device are accessories of the first electronic device; under the condition that the first electronic equipment comprises a tablet personal computer, the second electronic equipment is an electronic handwriting pen, and the third electronic equipment is a wireless keyboard; and under the condition that the first electronic equipment comprises an earphone box, the second electronic equipment is a left earphone, and the third electronic equipment is a right earphone.

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

Drawings

FIG. 1 shows a schematic diagram of a tablet computer accessory system;

FIG. 2 illustrates a schematic diagram of a tablet computer in use with a wireless accessory;

FIG. 3 shows a top view of the wireless keyboard after being snapped together;

fig. 4 is a schematic diagram of a tablet computer matching system before wireless keyboard adsorption, which is provided by the embodiment of the application;

Fig. 5 shows a schematic diagram of a tablet computer matching system before electronic handwriting pen adsorption, which is provided by the embodiment of the application;

fig. 6 is a schematic structural diagram of an earphone assembly according to an embodiment of the present application;

FIG. 7 illustrates a system architecture diagram of a wireless charging system;

Fig. 8 shows a system architecture diagram of a wireless charging system according to an embodiment of the present application;

fig. 9 shows a schematic structural diagram of a tablet computer according to an embodiment of the present application;

fig. 10 is a schematic diagram of an exemplary inverter circuit according to an embodiment of the present application;

Fig. 11 is a schematic diagram of a wireless charging procedure according to an embodiment of the present application;

fig. 12 shows a system architecture diagram of another wireless charging system provided by an embodiment of the present application;

Fig. 13 is a schematic structural diagram of a bootstrap circuit according to an embodiment of the present application;

fig. 14 shows a system architecture diagram of yet another wireless charging system provided by an embodiment of the present application;

fig. 15 shows a system architecture diagram of yet another wireless charging system provided by an embodiment of the present application;

fig. 16 shows a system architecture diagram of a one-to-many wireless charging system according to an embodiment of the present application;

fig. 17 is a schematic flow chart of a wireless charging control method according to an embodiment of the present application;

fig. 18 is a schematic flow chart of another wireless charging control method according to an embodiment of the present application;

Fig. 19 shows a schematic block diagram of an apparatus of an embodiment of the application.

Detailed Description

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

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

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

In embodiments of the application, the terms "upper," "lower," "left," "right," and the like may be defined by, but are not limited to, orientations relative to the component illustrated in the figures, it being understood that the directional terms may be relative in terms of their relative arrangement and clarity, and may be modified accordingly in response to changes in the orientation of the component illustrated in the figures.

In embodiments of the present application, unless explicitly specified and limited otherwise, the term "connected" is to be construed broadly, and for example, "connected" may be either a fixed connection, a removable connection, or an integral unit; can be directly connected or connected through an intermediate medium. Furthermore, the term "coupled" may be a means of electrical connection for achieving signal transmission.

In embodiments of the application, words such as "exemplary" or "such as" are used to mean serving as an example, instance, or illustration. Any embodiment or design described herein as "exemplary" or "e.g." in an embodiment should not be taken as preferred or advantageous over other embodiments or designs. Rather, the use of words such as "exemplary" or "such as" is intended to present related concepts in a concrete fashion.

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

And, the control terminal of each transistor used in the embodiment of the application is the gate of the transistor, the first connection terminal is one of the source and the drain of the transistor, and the second connection terminal is the other of the source and the drain of the transistor. Since the source and drain of a transistor may be symmetrical in structure, the source and drain may not be structurally different.

To facilitate the use of electronic devices, electronic devices often have mating accessories. For example, to enable diversified inputs to a tablet computer, the tablet computer may be equipped with wireless accessories such as a wireless keyboard, an electronic stylus, and the like. In order to improve the convenience of use and charging of users, electronic devices such as tablet computers and the like are often used for charging the wireless accessories.

Illustratively, fig. 1 shows a schematic diagram of a tablet computer accessory system. As shown in fig. 1, the tablet mating system may include a tablet 10, a wireless keyboard 20, and an electronic stylus 30.

The wireless keyboard 20 includes a keyboard main body 21, a tablet holder 22, and a connection portion 23. The tablet holder 22 is used for placing the tablet pc 10, and when the tablet pc 10 is in a use state, the keyboard main body 21 and the tablet holder form a certain included angle. The connecting portion 23 is used for connecting the keyboard main body 21 and the tablet holder 22, the connecting portion 23 can be made of flexible materials or a rotating shaft, a containing cavity 231 is formed in the connecting portion 23, an opening 232 is formed in one end of the containing cavity 231, and the containing cavity 231 is used for containing the electronic stylus 30.

Fig. 2 shows a schematic diagram of the cooperation of a tablet computer and a wireless accessory. As shown in fig. 2, the keyboard main body 21 and the tablet holder 22 can rotate relatively around the connection portion along the direction ①. And, the electronic stylus 30 may be received into the receiving cavity 231 through the opening 232 along the direction ②.

In the embodiment of the present application, the tablet computer 10 can perform wireless charging on the wireless keyboard 20 and the electronic stylus 30, i.e. a wireless charging scheme of "one-to-many". The structure of such a wireless charging scheme will be described next by two embodiments.

In one embodiment, fig. 3 shows a top view of the wireless keyboard after it is snapped together. As shown in fig. 3, a first wireless receiving coil (not shown) of the wireless keyboard 20 may be disposed in the keyboard body 21, so as to send a wireless charging signal to the wireless keyboard 20 through a first wireless transmitting coil (not shown) of the tablet computer 10 to charge the wireless keyboard when the keyboard body 21 is engaged with the tablet holder 22. And, the second wireless transmitting coil of the tablet computer 20 may be disposed at a side close to the receiving cavity 231, so that the tablet computer 10 may wirelessly charge the electronic stylus 30 after the electronic stylus 30 is received in the receiving cavity 231.

In another implementation manner, fig. 4 is a schematic diagram of a tablet computer matching system before wireless keyboard adsorption according to an embodiment of the present application. As shown in fig. 4, a first wireless receiving coil 221 is disposed in the tablet holder 22 of the wireless keyboard 20, a first wireless transmitting coil 11 is disposed in the tablet computer 10, and the first wireless transmitting coil 11 is disposed corresponding to the first wireless receiving coil 221. When the tablet pc 10 is placed on the tablet stand 22, the first wireless transmitting coil 11 is coupled with the first wireless receiving coil 221, and the tablet pc 10 transmits a wireless charging signal to the wireless keyboard 20 through the coupled first wireless transmitting coil 11 and first wireless receiving coil 221, so as to wirelessly charge the wireless keyboard 20.

Fig. 5 is a schematic diagram of a tablet computer matching system before electronic handwriting pen adsorption, which is provided by the embodiment of the application. As shown in fig. 5, a second wireless transmitting coil 12 is disposed in the tablet computer 10, a second wireless receiving coil 31 is disposed in the electronic stylus 30, and the second wireless transmitting coil 12 is disposed corresponding to the second wireless receiving coil 31. When the electronic stylus 30 is adsorbed on the side of the tablet computer 10 where the second wireless transmitting coil 12 is arranged, the second wireless transmitting coil 12 is coupled with the second wireless receiving coil 31, and the tablet computer 10 sends a wireless charging signal to the electronic stylus 30 through the coupled second wireless transmitting coil 12 and second wireless receiving coil 31 to charge the electronic stylus 30.

It should be noted that, the foregoing embodiments only show a feasible wireless charging scheme, and in the practical application process, the tablet computer 10 may also be enabled to wirelessly charge the wireless keyboard 20 and the electronic writing pen 30 through other feasible wireless charging manners, which is not limited in the embodiments of the present application.

And, it is understood that the foregoing merely schematically illustrates some of the components included in the tablet computer 10, the wireless keyboard 20, and the electronic stylus 30, and in fact, the tablet computer 10, the wireless keyboard 20, and the electronic stylus 30 may have more or fewer components than those described above, or may be combined with or separated from some components, or may have different arrangements of components. The illustrated components may be implemented in hardware, software, or a combination of software and hardware.

Fig. 6 is a schematic structural diagram of an earphone assembly according to an embodiment of the present application. As shown in fig. 6, the earphone assembly 40 may include an earphone case 41, a left earplug 42, and a right earplug 43.

The earphone case 41 includes an earphone receiving slot 411, a third wireless transmitting coil 412, and a fourth wireless transmitting coil 413. A third wireless receiving coil 421 is disposed in the left earplug 42, and the third wireless receiving coil 421 is disposed corresponding to the third wireless transmitting coil 412. A fourth wireless receiving coil 431 is provided in the right ear plug 43, and the fourth wireless receiving coil 431 is provided corresponding to the fourth wireless transmitting coil 413.

When the left ear bud 42 and the right ear bud 43 are placed in the ear bud receiving slot 411, the third wireless receiving coil 421 is coupled with the third wireless transmitting coil 412, the fourth wireless receiving coil 431 is coupled with the fourth wireless transmitting coil 413, the ear bud box 41 transmits a wireless charging signal to the left ear bud 42 through the coupled third wireless receiving coil 421 and third wireless transmitting coil 412, and transmits a wireless charging signal to the right ear bud 43 through the coupled fourth wireless receiving coil 431 and fourth wireless transmitting coil 413 to wirelessly charge the left ear bud 42 and the right ear bud 43.

After a scenario in which the electronic device wirelessly charges the accessory is introduced by the above example, a circuit configuration of the wireless charging system is explained next.

Fig. 7 shows a system architecture diagram of a wireless charging system. As shown in fig. 7, wireless charging system 100 may include an electronic device 110 and an accessory 120. The electronic device 110 may include a device battery 111 (i.e., a battery of the electronic device), a Direct Current-Direct Current (DCDC) circuit 112, a power Transmission (TX) chip 113, a resonant capacitor C1, and a resonant transmitting coil L1, among others.

The accessory 120 may include an accessory battery 121, a charging chip 122, a power Receiving (RX) chip 123, and a receiving coil L2.

During the wireless charging process, the battery 111 outputs a first direct current to the DCDC circuit 112, and after voltage conversion by the DCDC circuit 112, a second direct current is obtained. After the DCDC circuit 112 supplies the second direct current to the TX chip 113, the TX chip 113 converts the second direct current into the first alternating current and supplies the first alternating current to the transmitting coil L1. The transmitting coil L1 generates an alternating electromagnetic field in response to the first alternating current.

And, the receiving coil L2 generates a second alternating current after sensing the alternating electromagnetic field, and supplies the second alternating current to the RX chip 123. The RX chip 123 converts the second alternating current into a third direct current and supplies the third direct current to the charging chip 122. The charging chip 122 charges the battery 121 with the third direct current.

The inventor finds through research that if a single charging circuit (i.e. a one-to-one wireless charging scheme) is respectively arranged for the electronic handwriting pen and the wireless keyboard in the electronic equipment, the charging circuits are scattered, and the integration level is low.

And, the inventor found through researches that, in the electronic devices such as the tablet computer 10 and the earphone box 41, taking the tablet computer 10 as an example, when the accessories such as the wireless keyboard 20 and the electronic stylus 30 are charged, the charging power is often only about 1W, and accordingly, the electronic devices can perform low-power wireless charging on the accessories, for example, the charging power is in the range of 1-5W. Furthermore, it should be noted that, taking a charging base (such as a vertical charging base) as an example, the charging power may reach 50W or 80W, that is, for high-power charging electronic devices such as a mobile phone, a notebook computer, and a charging base, the charging power may be higher, for example, may reach hundreds of watts (such as 500W). That is, in the embodiment of the present application, the charging power of the electronic device such as the tablet pc 10 to the accessory is far lower than that of the electronic device charged with high power.

In addition, taking a tablet computer as an example, the tablet computer is continuously developed towards the direction of light and thin, so how to improve the light and thin of devices such as the tablet computer is a technical problem to be solved.

Based on the above, the embodiment of the application provides a one-to-many wireless charging scheme, namely, the electronic equipment can wirelessly charge a plurality of accessories. It should be noted that the embodiment of the present application is applicable to electronic devices, such as tablet computers, earphone boxes, etc., that wirelessly charge accessories with low power. The low power range may be 1-5 w. For example, 1W, 1.25W, 1.5W, 1.75W, 2W, 2.25W, 2.5W, 2.75W, 3W, 3.25W, 3.5W, 3.75W, 4W, 4.25W, 4.5W, 4.75W, 5W. And, the electronic device according to the embodiment of the present application may be an electronic device that is developed toward light and thin.

For ease of illustration, the wireless charging scheme will be described below using the electronic device as tablet 200, and the plurality of accessories including electronic stylus 300 and wireless keyboard 400. The tablet pc 200 may be implemented as the tablet pc 10 in fig. 1-5, the electronic stylus 300 may be implemented as the electronic stylus 30 in fig. 1-5, and the wireless keyboard 400 may be implemented as the wireless keyboard 20 in fig. 1-5.

Fig. 8 shows a system architecture diagram of a wireless charging system according to an embodiment of the present application. As shown in fig. 8, the wireless charging system may include a tablet computer 200, an electronic stylus 300, and a wireless keyboard 400. In the embodiment of the present application, the tablet pc 200 wirelessly charges the accessory with low power.

Tablet computer 200 may include a tablet battery 210, a DCDC circuit 220, a TX chip 230 (i.e., a wireless transmit chip), a first capacitor C11, a second capacitor C12, a first transmit coil L11, and a second transmit coil L12. Illustratively, functional devices such as the tablet battery 210, the DCDC circuit 220, the TX chip 230, the first capacitor C11, the second capacitor C12, the first transmitting coil L11, the second transmitting coil L12, etc., may be disposed on a printed circuit board (Printed Circuit Board, PCB) of the tablet computer 200. Furthermore, it should be noted that the TX chip 230, the first capacitor C11, the second capacitor C12, the first transmitting coil L11, and the second transmitting coil L12 may belong to a wireless charging circuit of the tablet pc 200.

For the connection relationship of the above functional devices, as shown in fig. 8, the output end of the flat battery 210 is connected to one end of the DCDC circuit 220, the other end of the DCDC circuit 220 is connected to the input end of the TX chip 230, the first output port AC1 of the TX chip 230 is connected to one end of the first capacitor C11 and one end of the second capacitor C12, the other end of the first capacitor C11 is connected to one end of the first transmitting coil L11, the other end of the first transmitting coil L11 is connected to the second output port AC2 of the TX chip 230, the other end of the second capacitor C12 is connected to one end of the second transmitting coil L12, and the other end of the second transmitting coil L12 is connected to the second output port AC2 of the TX chip 230. The first output port AC1 is a common connection terminal, and the second output port AC2 and the third output port AC3 are non-common terminals.

For tablet battery 210, it may be the battery of tablet computer 200 for powering the various components in tablet computer 200, and may also provide electrical power to external accessories of the electronic device.

And, for DCDC circuit 220, it may be implemented as a BOOST (BOOST) converter. Fig. 9 is a schematic structural diagram of an exemplary tablet computer according to an embodiment of the present application. As shown in fig. 9, DCDC circuit 220 may be implemented as BOOST converter 221. The BOOST converter 221 may be implemented as a BOOST circuit, a BOOST chip, or the like, which is not particularly limited. In addition, it is understood that in actual practice, the DCDC circuit 220 may be configured as a BUCK (BUCK) converter, a BUCK-BOOST (BUCK-BOOST) converter, or other circuits or functional devices that perform voltage adjustment by boosting and/or BUCK, which is not particularly limited.

And, the first capacitor C11 and the first transmitting coil L11 may belong to a first resonance circuit (or referred to as a wireless charging path 1), and the second capacitor C12 and the second transmitting coil L12 may belong to a second resonance circuit (or referred to as a wireless charging path 2). The first capacitor C11 compensates the alternating current on the first resonant circuit, and the second capacitor C12 compensates the alternating current on the second resonant circuit. It should be noted that, in the embodiment of the present application, other devices having an ac compensation function, such as a compensation inductor, may be further disposed on the first resonant circuit and the second resonant circuit, which is not limited in particular.

And, for TX chip 230, it may be used to convert direct current to alternating current. In some embodiments, with continued reference to fig. 9, tx chip 230 may include an inverter circuit 231 (i.e., a processing circuit), a microcontroller (Micro Controller Unit, MCU) 232, a first PMOS transistor Q11 (i.e., a first MOS switch), and a second PMOS transistor Q12 (i.e., a second MOS switch).

The inverter circuit 231 is configured to convert the dc power output by the BOOST converter 221 into ac power. Specifically, as shown in fig. 9, an input terminal of the inverter circuit 231 is connected to an input terminal of the BOOST converter 221, and a first output terminal of the inverter circuit 231 is connected to the first output port AC1 of the TX chip 230. In one embodiment, the inverter circuit 231 may be implemented as a full bridge inverter circuit. Fig. 10 is a schematic diagram illustrating an exemplary inverter circuit according to an embodiment of the present application. As shown in fig. 10, the inverter circuit 231 may include a first switching tube Q21, a second switching tube Q22, a third switching tube Q23, and a fourth switching tube Q24. The first connection end of the first switching tube Q21 and the first connection end of the second switching tube Q22 may be commonly connected to the first output end of the BOOST converter 221, the second connection end of the first switching tube Q21 is connected to the first connection end of the third switching tube Q23, the second connection end of the second switching tube Q22 is connected to the first connection end of the fourth switching tube Q24, the second connection end of the third switching tube Q23 and the second connection end of the fourth switching tube Q24 may be commonly connected to the second output end of the BOOST converter 221, and the BOOST converter 221 may output the direct current Uin to the inverter through the first output end and the second output end. And a node a is provided between the second connection end of the first switching tube Q21 and the first connection end of the third switching tube Q23, and the node a may be used as the first output end of the inverter circuit 231. And, a node B is disposed between the second connection terminal of the second switching tube Q22 and the first connection terminal of the fourth switching tube Q24, and the node B may be used as the second output terminal of the inverter circuit 231. The inverter circuit 231 can convert the direct current into the alternating current by controlling the on-off of the first to fourth switching transistors Q21 to Q24. It should be noted that, in the embodiment of the present application, the inverter circuit 231 may be implemented as another circuit or device having a dc-ac conversion function, which is not limited in particular.

And, MCU232 may be an internal controller of TX chip 230, which may perform on-off control on MOS transistors in the TX chip. With continued reference to fig. 10, the mcu232 has a first control end and a second control end, where the first control end may be connected to the control end of the first PMOS transistor Q11, and the second control end may be connected to the control end of the second PMOS transistor Q12, so as to control the first PMOS transistor Q11 and the second PMOS transistor Q12 to be turned on or off. In the embodiment of the application, when any one of the first PMOS transistor Q11 and the second PMOS transistor Q12 is in the on state, the other one of the first PMOS transistor Q11 and the second PMOS transistor Q12 is in the off state. In addition, in the embodiment of the present application, the MCU232 is an original controller in the TX chip, for example, the inverter circuit 231 may be controlled. It should be noted that, in the embodiment of the present application, the MCU232 may also be implemented as other controllers having a control function, which is not limited in particular.

And, for the first PMOS transistor Q11, it may be used to control whether the first emitter coil L11 is operating. When the first PMOS transistor Q11 is turned on, the first transmitting coil L11 may convert the ac power output by the inverter circuit into an alternating magnetic field, so as to transmit the electric power to the first receiving coil L21 of the electronic stylus 300 in the form of the alternating magnetic field, so as to charge the electronic stylus. And when the first PMOS tube Q11 is disconnected, the first emitting coil L11 cannot generate an alternating magnetic field. Specifically, with continued reference to fig. 9, a first connection end of the first PMOS transistor Q11 may be connected to the second output end of the inverter circuit 231, and a second connection end of the first PMOS transistor Q11 may be connected to the second output port AC2 of the TX chip to be connected to the other end of the first transmitting coil L11 through the second output port AC 2.

And, for the second PMOS transistor Q12, it may be used to control whether the second transmitting coil L12 works, and the specific control manner thereof may refer to the control of the first PMOS transistor Q11 on the first transmitting coil L11, which is not described herein. Specifically, with continued reference to fig. 9, the first connection end of the second PMOS transistor Q12 may be connected to the second output end of the inverter circuit 231, and the second connection end of the second PMOS transistor Q12 may be connected to the third output port AC3 of the TX chip to be connected to the other end of the second transmitting coil L12 through the third output port AC 3.

Having described the specific structure of tablet computer 200, the following description of the specific structure of electronic stylus 300 continues.

The electronic stylus 300 may include a first receiving coil L21, a stylus RX chip 310 (i.e., a stylus RX chip for converting alternating current induced by the first receiving coil L21 into direct current), a stylus charging chip 320 (i.e., a stylus charging chip for charging a stylus battery 330), and a stylus battery 330 (i.e., a stylus battery for powering internal devices of the electronic stylus). The first receiving coil L21 is disposed corresponding to the first transmitting coil L11. One end of the first receiving coil L21 is connected to a first input port of the stylus RX chip 310, the other end of the first receiving coil L21 is connected to a second input port of the stylus RX chip 310, an output end of the stylus RX chip 310 is connected to an input end of the stylus charging chip 320, and an output end of the stylus charging chip 320 is connected to the stylus battery 330. The stylus battery 330, i.e. the battery of the electronic stylus 300, is used for supplying power to each component of the electronic stylus 300, and can also receive the electric energy input from the outside of the electronic stylus 300 and store the electric energy.

Having described the electronic stylus 300, the description of the wireless keyboard 400 continues.

The wireless keyboard 400 may include a second receiving coil L22, a keyboard RX chip 410 (i.e., an RX chip of the wireless keyboard for converting alternating current induced by the second receiving coil L22 into direct current), a keyboard charging chip 420 (i.e., a charging chip of the wireless keyboard for charging the wireless keyboard battery 430), and a keyboard battery 430 (i.e., a battery of the wireless keyboard for supplying power to internal devices of the wireless keyboard). Wherein the second receiving coil L22 is disposed corresponding to the second transmitting coil L12. One end of the second receiving coil L22 is connected to the first input port of the keyboard RX chip 410, the other end of the second receiving coil L22 is connected to the second input port of the keyboard RX chip 410, the output end of the keyboard RX chip 410 is connected to the input end of the keyboard charging chip 420, and the output end of the keyboard charging chip 420 is connected to the keyboard battery 430. The keyboard battery 430, i.e. the battery of the wireless keyboard 400, is used for supplying power to each component of the wireless keyboard 400, and can also receive electric energy input from the outside of the wireless keyboard 400 and store the electric energy.

Having described the structure of tablet 200, electronic stylus 300, and wireless keyboard 400, a wireless charging process for a wireless charging system is described next.

In the embodiment of the present application, after the electronic stylus 300 and the wireless keyboard 400 are both adsorbed to the tablet pc 200 (for example, both are placed in a preset charging position or a preset charging area, for example, the electronic stylus 300 is received in the receiving cavity 231 shown in fig. 3, and the tablet pc 200 is placed in the tablet stand 22 shown in fig. 4), the first transmitting coil L11 is coupled with the first receiving coil L21, and the second transmitting coil L12 is coupled with the second receiving coil L22, so that the tablet pc 200 can perform a "one-to-two" charging procedure on the electronic stylus 300 and the wireless keyboard 400.

In the one-to-two wireless charging process, the tablet pc 200 can perform time-sharing charging on the electronic stylus 300 and the wireless keyboard 400. Fig. 11 is a schematic diagram illustrating a wireless charging procedure according to an embodiment of the present application. As shown in fig. 11, in a first time period t1, the tablet pc 200 performs a first round of wireless charging on the electronic stylus 300; in a second time period t2, the tablet computer 200 performs a first round of wireless charging on the wireless keyboard 400; in a third time period t3, the tablet computer 200 performs a second round of wireless charging on the electronic stylus 300; and, in a fourth time period t4, the tablet computer 200 performs a second round of wireless charging on the wireless keyboard 400; … …; the tablet pc 200 charges the electronic stylus 300 and the wireless keyboard 400 in turn until the charging is completed. The time periods may be the same or different, and may be determined by the AP according to the specific charging conditions, which is not particularly limited.

Specifically, during the charging process of the tablet pc 200 to the electronic stylus 300 (for example, the first period t1 and the third period t3 described above), the MCU232 provides the first level to the first PMOS transistor Q11, the first PMOS transistor Q11 is turned on, and the second PMOS transistor Q12 is turned off. The first level may be a low level in the embodiment of the present application, such as 0V, so that the turn-on voltage V _GS (i.e. the voltage of the gate with respect to the source) is less than 0 and less than the negative value of the preset voltage threshold. And, after the first PMOS transistor Q11 is turned on, the first emitter coil L11 may convert the ac power supplied from the inverter circuit 231 into an alternating magnetic field. The first receiving coil L21 of the electronic stylus 300 senses the alternating magnetic field to generate alternating current. The stylus RX chip 310 may convert the ac power induced by the first receiving coil L21 into dc power, and charge the stylus battery 330 with the converted dc power through the stylus charging chip 320.

And, in the process of charging the wireless keyboard 400 by the tablet pc 200 (for example, the second time period t2 and the fourth time period t4 described above), the MCU232 provides the first level to the second PMOS transistor Q12, the second PMOS transistor Q12 is turned on, and the first PMOS transistor Q11 is turned off. And, after the second PMOS transistor Q12 is turned on, the second transmitting coil L12 may convert the alternating current provided by the inverter circuit 231 into an alternating magnetic field. The alternating magnetic field is sensed by the second receiving coil L22 of the wireless keyboard 400 to generate alternating current. The keypad RX chip 410 may convert the ac power induced by the second receiving coil L22 into dc power, and charge the keypad battery 430 with the converted dc power through the keypad charging chip 420.

In the above circuit provided by the embodiment of the application, one-to-two charging of the electronic handwriting pen and the wireless keyboard can be realized through the TX chip 230, and compared with one-to-one charging scheme, the technical scheme provided by the embodiment of the application improves the integration level of the wireless charging circuit in the tablet personal computer. It should be noted that, the solution of the embodiment of the present application may also be applicable to other electronic devices with low charging power besides tablet computers, which is not limited in particular. And the electronic equipment can also carry out one-to-two or one-to-many wireless charging for two or more accessories with lower power consumption besides the electronic handwriting pen and the wireless keyboard.

And because the first PMOS tube Q11 and the second PMOS tube Q12 are integrated inside the TX chip, a discrete MOS tube does not need to be arranged outside the TX chip, a peripheral design circuit is simplified, and the area of a PCB (printed circuit board) is not occupied. And the integration level of the circuit (such as the PMOS tube) in the TX chip is higher than that of the circuit on the PCB, so that the area of the PCB is reduced and the cost is saved. And, due to the development of the tablet personal computer towards the direction of light and thin, the area of the PCB is reduced, so that the light and thin of the tablet personal computer can be further improved.

And compared with the high-power charged electronic equipment, the high-power charged electronic equipment has larger charging power, and the switching tube can possibly cause the problem of heating of the device due to the larger charging power, so that the safety and the service life of the equipment are affected. In the high-power charged electronic equipment, the heating power of the MOS tube is often lower due to the fact that the impedance of the MOS tube is larger, so that a larger switch tube is selected in the high-power charged electronic equipment, and the heating problem of the MOS tube is reduced in a mode of reducing the impedance of the MOS tube. However, the larger MOS transistor cannot be integrated inside the TX chip, so the MOS transistor of the electronic device charged with high power needs to be disposed on the PCB circuit board, which occupies a larger circuit board area. In the embodiment of the application, the inventor finds that the equipment such as a tablet personal computer is low-power charging equipment, and because the charging power is smaller, the heating problem of the MOS tube is less obvious, so that the requirement on impedance of the MOS tube is not high, the MOS tube with smaller volume can be integrated in the TX chip in the low-power charging equipment, and the heat dissipation safety of the electronic equipment is ensured while the area of a PCB (printed circuit board) is reduced.

The embodiment of the application also provides another wireless charging system. Fig. 12 shows a system architecture diagram of another wireless charging system according to an embodiment of the present application. Note that, fig. 12 is the same as the electronic stylus 300 and the wireless keyboard 400 in fig. 8, and only the structure of the tablet pc 200 is shown in fig. 12.

The tablet pc 200 shown in fig. 12 is different from the tablet pc 200 shown in fig. 8 in that the TX chip 230 in fig. 12 further includes a bootstrap circuit 233, a first NMOS transistor Q31, and a second NMOS transistor Q32.

For the bootstrap circuit 233, it is used to raise the driving voltage of the NMOS transistor. In some embodiments, to further reduce the area of the PCB circuit board, bootstrap circuit 233 may be an original bootstrap circuit in the TX chip, for example, it may be a bootstrap circuit in inverter bridge 231. Or the bootstrap circuit 233 may also be a newly added circuit. Illustratively, the bootstrap circuit in the embodiments of the present application may implement a bootstrap capacitor. Fig. 13 is a schematic structural diagram of a bootstrap circuit according to an embodiment of the present application. As shown in fig. 13, the bootstrap circuit 233 may include a bootstrap capacitor Ca. Taking the first NMOS transistor Q31 as an example, one end a1 of the bootstrap capacitor Ca is connected to the first connection end of the first NMOS transistor Q31, and the other end a2 of the bootstrap capacitor Ca is connected to the control end of the second NMOS transistor Q31. According to the characteristics of the bootstrap capacitor, when the voltage Va is applied to the first connection terminal of the first NMOS transistor Q31, the voltage at one end a1 of the bootstrap capacitor Ca increases, so that the voltage at the other end a2 of the bootstrap capacitor Ca also increases, and thus the voltage at the other end a2 of the bootstrap capacitor Ca can turn on the first NMOS transistor Q31. For example, if the voltage of the first connection end (assumed to be the source) of the first NMOS transistor Q31 is 5V, the bootstrap circuit 232 may raise the voltage of the control end of the first NMOS transistor Q31 to 10V, and the turn-on voltage V _GS (i.e. the voltage of the gate relative to the source) reaches 5V (greater than the preset voltage threshold), so as to turn on the first NMOS transistor Q31.

It should be noted that, the connection manner of the bootstrap capacitor Ca and the second NMOS transistor Q32, and the control manner of the second NMOS transistor Q32 are similar to those of the first NMOS transistor Q31, and the related description of the above parts will be referred to and will not be repeated. Also, it should be noted that the bootstrap circuit 233 may be implemented as other circuits capable of raising the driving voltage of the NMOS transistor, such as a combination circuit of a bootstrap capacitor and a bootstrap resistor, which is not limited in particular.

For the connection relationship and control manner of the first NMOS transistor Q31 and the second NMOS transistor Q32, reference may be made to the description related to the first PMOS transistor Q11 and the second PMOS transistor Q12 in the foregoing embodiment of the present application, which is not specifically limited.

Since the MCU232 cannot provide the driving voltage of the NMOS transistor itself, in the embodiment of the present application, the voltage output by the MCU can be raised to the driving voltage of the NMOS transistor by the bootstrap circuit built in the TX chip. The NMOS tube has smaller volume (or size or occupied area on the TX chip) than the PMOS tube, so that the areas of the TX chip and the PCB can be further reduced. Optionally, the bootstrap circuit may be an original bootstrap circuit in the TX chip, so that the integration level of the TX chip can be further improved and precise control of the TX chip on the charging process is ensured.

The embodiment of the application also provides a wireless charging system. Fig. 14 shows a system architecture diagram of yet another wireless charging system according to an embodiment of the present application.

Fig. 14 is different from the tablet pc 200 in fig. 13 in that the TX chip 230 includes a first output port AC1 to a fourth output port AC4, and a first NMOS transistor Q31 and a second NMOS transistor Q32 are disposed outside the TX chip 230, that is, the first NMOS transistor Q31 and the second NMOS transistor Q32 are disposed on the PCB circuit board. The connection manner of the first output port AC1 and the second output port AC2 is the same as the connection manner of the two ports in the tablet computer shown in fig. 8, which is not described herein. The third output port AC3 is connected to the gate of the first NMOS transistor Q31, and the fourth output port AC4 is connected to the gate of the second NMOS transistor Q32.

In the wireless charging system provided by the embodiment of the application, the bootstrap circuit 233 can output the driving voltage of the NMOS tube, so that the PMOS tube on the PCB circuit board can be replaced by the NMOS tube, and the size of the NMOS tube is smaller than that of the PMOS tube, so that the area of the PCB circuit board is saved, and the light and thin weight of the tablet personal computer is further improved. And under the condition that the bootstrap circuit is an original circuit of the TX chip, the control of the NMOS tube can be realized without setting an additional circuit, and the area of a PCB circuit board is further saved.

The embodiment of the application also provides a wireless charging system. Fig. 15 shows a system architecture diagram of yet another wireless charging system according to an embodiment of the present application.

Fig. 15 is different from the tablet pc 200 shown in fig. 10 in that the controllers of the first PMOS transistor Q11 and the second PMOS transistor Q12 are replaced with an application processor (Application Processor, AP) 240 by the MCU 232. Specifically, as shown in fig. 15, tablet computer 200 further includes an AP240, and TX chip 230 further includes a first switch control pin P1 and a second switch control pin P2.

The AP240 is configured to control on and off of the first PMOS transistor Q11 and the second PMOS transistor Q12. When the electronic stylus 300 needs to be charged, the AP240 drives the first PMOS transistor Q11 to be turned on and drives the second PMOS transistor Q12 to be turned off through the first switch control pin P1. When the wireless keyboard 400 needs to be charged, the AP240 drives the second PMOS transistor Q12 to be turned on and drives the first PMOS transistor Q11 to be turned off through the second switch control pin P2.

It should be noted that, in the embodiment of the present application, other controllers having a control function for the wireless charging process besides the AP may be used, which is not particularly limited.

And, it should be further noted that, the foregoing embodiment illustrates the technical solution of the embodiment of the present application by taking the one-to-two wireless charging scheme as an example, and it should be understood that the foregoing embodiment of the present application may also implement the one-to-many wireless charging scheme (where one electronic device charges three or more accessories wirelessly).

Fig. 16 shows a system architecture diagram of a one-to-many wireless charging system according to an embodiment of the present application. Next, a description will be given of a one-to-many wireless charging system corresponding to the wireless charging system shown in fig. 8 with reference to fig. 16. It should be noted that, the wireless charging scheme shown in other embodiments may also be implemented as a one-to-many wireless charging system, and the implementation scheme is similar to that of fig. 16, which is not repeated herein.

As shown in fig. 16, the tablet pc 200 includes: first to nth output ports AC1 to CAN, first to nth capacitances C11 to C1N, first to nth transmit coils L11 to L1N, TX, and chip 230.TX chip 230 may include first PMOS tube Q11 through N-th PMOS tube Q1N, MCU232. The MCU232 includes a first control end to an nth control end, where N is any positive integer greater than or equal to 3.

One end of the ith capacitor C1i is connected to the first output port AC1, the other end of the ith capacitor C1i is connected to one end of the ith transmitting coil L1i, the other end of the ith transmitting coil L1i is connected to the second connection end of the ith PMOS transistor Q1i through the ith output port ACi, the first connection end of the ith PMOS transistor Q1i is connected to the second output end of the inverter circuit 231, and the control end of the ith PMOS transistor Q1i is connected to the ith control end of the MCU 232. Wherein i is any positive integer of 1 or more and N or less.

In the embodiment of the present application, the ith capacitor C1i and the ith transmitting coil L1i form a wireless charging path i, and the ith PMOS transistor Q1i is used to control whether the wireless charging path i works, and when the wireless charging path i works, the tablet pc 200 can perform wireless charging on the ith accessory. Specifically, the MCU232 controls one MOS transistor from the first PMOS transistor to the N-th PMOS transistor Q1N to be turned on at any time, so as to perform time-sharing wireless charging on the N accessories.

Through the embodiment, through integrating more MOS tubes, a single TX chip can integrate a one-to-N charging function, so that the TX chip can be applied to one-to-N application scenes of the tablet personal computer. Optionally, for the scheme provided by the embodiment of the application, through flexible access of the transmitting coils, the TX chip can be applied to a plurality of different one-to-many charging scenes, for example, when any two transmitting coils are accessed, the TX chip can be applied to one-to-two charging scenes, and when N transmitting coils are accessed, the TX chip can be applied to one-to-N charging scenes.

In addition, it should be noted that, after the MOS transistor integration scheme shown in fig. 16, in a one-to-N charging scheme, N MOS transistors may be turned on in turn (specific turn-on sequence is not changed) in a manner of MOS transistor multiplexing or the like, for example, if the first output end of the inverter circuit may be connected to the first output port to the M1 output port through the M1 MOS transistor, and the second output end of the inverter circuit may be connected to the m+1st output port to the m1+m2 output port through the M2 MOS transistor, then independent control of the m1×m2 wireless charging paths may be implemented through the first output port to the m1+m2 output port, that is, time-sharing charging control may be performed on the m1×m2 accessories. It should be noted that, the one-to-N wireless charging control may also be implemented by other MOS tube multiplexing modes inside the TX chip, which is not particularly limited.

In some embodiments, in the case where the above-mentioned MOS transistors (the first PMOS transistor Q11 and the second PMOS transistor Q12, or the first NMOS transistor Q31 and the second NMOS transistor Q32) are disposed inside the TX chip 230, in the above-mentioned embodiments, the TX chip 230 further includes a heat conducting layer. One part of the heat conducting layer covers the upper part of the MOS tube, and the other part of the heat conducting layer is in contact with a colder area (namely an area with heat dissipation performance or temperature lower than that of the MOS tube) in the TX chip, so that heat emitted by the MOS tube is transferred to the colder area through the heat conducting layer. The material of the heat conducting layer may be graphite or other materials with better heat conducting performance, and is not particularly limited.

It should be noted that, when the MOS transistor is integrated into the TX chip, the size of the MOS transistor is correspondingly reduced due to the integration of the TX chip and the peripheral circuit, and the reduction of the size of the MOS transistor may cause the increase of the impedance of the MOS transistor, which may cause the overheat of the MOS transistor to affect the service life and the safety of the electronic device. Through the arrangement of the heat conducting layer, the area of the PCB is saved, and meanwhile, the safety of the electronic equipment is considered.

After the wireless charging scheme provided by the embodiment of the present application is described through the foregoing embodiment specification, the wireless charging control logic of the embodiment of the present application is described next.

Fig. 17 shows a flow chart of a wireless charging control method according to an embodiment of the present application. The wireless charging method shown in fig. 17 may be applied to the wireless charging system in which the MOS transistor is controlled by the MCU, for example, in the wireless charging system shown in any of the embodiments in connection with fig. 8 to 16.

As shown in fig. 17, the wireless charging method may include the following steps S1701 to S1711.

S1701, when the electronic stylus is adsorbed (i.e. adsorbed to or stored in the tablet computer), the first sensor detects the first detection signal.

In S1701, a first detection signal sensor may be disposed on the electronic stylus side, and a first detection signal transmitter may be disposed at a first preset position of the tablet computer, so that when the electronic stylus is adsorbed to the first preset position, a first detection signal sent by the first detection signal transmitter may be collected by the first detection signal sensor, at this time, the electronic stylus may send the detected first detection signal to the tablet computer through the communication module, and after the tablet computer receives the first detection signal through the communication module, the tablet computer sends the first detection signal to the AP. The first detection signal may be an electrical signal, a magnetic signal, an optical signal, a pressure signal, or the like, which has sensing capability. The signal sensor provided on the electronic stylus may be, for example, a hall sensor, a compass, or the like, which has magnetic signal sensing capability. And arranging a device with magnetic signal transmitting capability such as a magnet on a first preset position of the tablet personal computer. The first detection signal may be a magnetic signal.

It should be noted that, in the embodiment of the present application, the first detection signal sensor may be further disposed on the tablet pc according to an actual situation, and the first detection signal transmitter may be disposed on the electronic handwriting pen, where the first detection signal sensor may transmit the detected first detection signal to the AP.

In the embodiment of the application, the tablet personal computer can also detect whether the electronic handwriting pen is adsorbed to the first preset position by detecting the Q value through the Q value detection circuit and other modes. Specifically, the tablet computer detects the Q value of the first transmitting coil L11. And under the condition that the detected Q value is greater than or equal to a preset Q value threshold value, determining that the electronic stylus is adsorbed to a first preset position. The Q value of the first transmitting coil L11 may be calculated from the inductance value, ac impedance, and resonant frequency of the transmitting coil, for example. The method for detecting the Q value is not limited in the embodiment of the application. It should be noted that, in the embodiment of the present application, other ways of detecting whether the electronic stylus is adsorbed (or in place) may be used, which is not limited in particular.

S1702, the first detection signal sensor sends a first detection signal to the AP.

S1703, the second detection signal sensor detects a second detection signal when the wireless keyboard is adsorbed.

In some embodiments, a second detection signal sensor may be provided at the wireless keyboard and a second detection signal transmitter may be provided at a second preset location of the tablet computer. In still other embodiments, a second detection signal transmitter may be disposed on the wireless keyboard, and a second detection signal sensor may be disposed at a second preset position of the tablet computer, where the specific location is not limited. It should be noted that, the detection manners of the first detection signal and the second detection signal are similar, and reference may be made to the related description of S1701, which is not repeated.

S1704, the second detection signal sensor sends a second detection signal to the AP.

S1705, the AP determines a gating strategy according to each charging information (such as the information of the residual electric quantity, the adsorption sequence and the like) under the condition that the AP receives the first detection signal and the second detection signal. The gating strategy is a strategy that a first MOS switch and a second MOS switch are turned on and off in each time period. In some embodiments, the first MOS switch may be a first PMOS transistor Q11 and the second MOS switch may be a second PMOS transistor Q12. In other embodiments, the first MOS switch may be a first NMOS transistor Q31 and the second MOS switch may be a second NMOS transistor Q32.

For example, the AP may determine the turn-on sequence of the first MOS switch and the second MOS switch, i.e., the charging sequence of the electronic stylus and the wireless keyboard. For example, preferential charging with low remaining capacity, preferential charging with adsorption first, and the like. Optionally, the gating strategy may further include respective on-time durations of the first MOS switch and the second MOS switch, that is, charging durations of the electronic stylus and the wireless keyboard. Optionally, the gating strategy further includes control information such as charging power that can affect the charging process, which is not particularly limited.

S1706, the AP judges whether the first MOS switch needs to be conducted according to the gating strategy. If the determination result is yes, step S1707 is skipped, and if the determination result is no, step S1710 is skipped.

Illustratively, continuing with the example of FIG. 11, the gating strategy may include: selecting a first MOS switch to be conducted in a first time period t 1; selecting a second MOS switch to be conducted in a second time period t 2; … …. In the first period t1, the AP may determine that the first MOS switch needs to be turned on according to the gating policy, and accordingly, the step S1707 is continuously performed. And, in the second period t2, if the AP determines that the second MOS switch needs to be turned on according to the gating policy, step S1710 may be adjusted.

S1707, if the AP judges that the first MOS switch needs to be turned on, the AP sends notification information to the MCU. In some embodiments, the AP and MCU may be connected via a communication bus such as I2C.

For the notification information, it is used for notifying the MCU to control the first MOS switch to be on and the second MOS switch to be off. Illustratively, the notification information may include gating policies, information detected by the MCU, and the like.

In some embodiments, the AP may send a notification message to the MCU once when the on-off states of the first MOS switch and the second MOS switch change. For example, when the first MOS switch is turned on, notification information is sent once; when the second MOS switch is turned on, the notification information is sent once again; … ….

In other embodiments, the AP may send notification information to the MCU when performing the first switching control, and after receiving the gating policy in the notification information, the MCU controls the first MOS switch and the second MOS switch to be turned on or off according to the gating policy.

S1708, the MCU receives the notification information, controls the first MOS switch to be turned on and controls the second MOS switch to be turned off.

By the control in S1708, the wireless charging path 1 can be controlled to be turned on, so that the electronic stylus can be charged through the wireless charging path 1.

S1709, the AP judges whether the second MOS switch needs to be conducted according to the gating strategy. If the determination result is yes, step S1710 is skipped, and if the determination result is no, step S1705 is returned.

The specific content of S1709 is similar to S1705, and reference may be made to the description of S1705 in the above section of the embodiment of the present application, which is not repeated here.

S1710, if the AP judges that the second MOS switch needs to be turned on, the AP sends notification information to the MCU.

The content of S1710 is similar to S1707, and reference may be made to the description of S1706 in the above section of the embodiment of the present application, which is not repeated here.

S1711, the MCU receives the notification information and controls the first MOS switch to be turned off and controls the second MOS switch to be turned on. The content of S1711 is similar to that of S1707, and reference may be made to the description of S1707 in the above-mentioned parts of the embodiment of the present application, which is not repeated here.

By the control in S1711, the wireless charging path 2 can be controlled to be turned on, so that the wireless keyboard can be charged through the wireless charging path 2.

Through the steps 1701 to 1711, the tablet personal computer can accurately control the wireless charging process of one-to-two battery charging, and the charging precision is improved. And, it can be understood that the wireless charging process of one power on/off is similar to the charging process described above, except that after S1711, the AP further includes determining whether to turn on the third MOS switch, notifying the MCU of whether to turn on the third MOS switch, and turning off the other N-1 MOS switches; … …; the steps until the AP judges whether to turn on the Nth MOS switch, informs the MCU to turn on the Nth MOS switch and turn off the other N-1 MOS switches are omitted.

The first MOS switch and the second MOS switch can be further controlled by the AP to be on-off. Fig. 18 is a schematic flow chart of another wireless charging control method according to an embodiment of the present application. Among them, another wireless charging control method shown in fig. 18 may include S1801 to S1809.

As each MOS switch in 18 is controlled by the AP, correspondingly, as can be seen from comparing fig. 17 and fig. 18, the difference between the two is that, as shown in steps S1806-S1809, when it is determined that the first MOS switch needs to be turned on, the AP can directly control the first MOS switch to be turned on and the second MOS switch to be turned off. And when the second MOS switch is determined to be required to be turned on, the AP can directly control the first MOS switch to be turned off and the second MOS switch to be turned on.

For other details of each step of another wireless charging control method shown in fig. 18, reference may be made to the description of each step of the above-mentioned wireless charging control method shown in fig. 17, which is not repeated herein.

In some embodiments, in the above wireless charging control method, the following steps D1 to D3 may be further included.

In step D1, the temperature detection module detects the switching temperature data of the target MOS switch.

The target MOS switch may be a switch in an on state of the first MOS switch and the second MOS switch. Specifically, the temperature detection module may detect switching temperature data of the first MOS switch when the first MOS switch is on and the second MOS switch is off. And when the first MOS switch is turned off and the second MOS switch is turned on, the temperature detection module can detect the switching temperature data of the second MOS switch.

Switch temperature data, i.e. data related to the switch temperature, such as the switch temperature value and/or the temperature rise rate, etc.

And D2, under the condition that the switching temperature data exceeds the normal value range of the temperature data, the AP or the MCU (i.e. the controller of the target MOS switch) turns off the target MOS switch.

In some embodiments, when the switching temperature data includes a switching temperature value, the AP or the MCU may turn off the target MOS switch if the switching temperature value is out of the temperature range. In other embodiments, when the switching temperature data includes a temperature ramp rate, the AP or the MCU may turn off the target MOS switch if the temperature ramp rate is outside the ramp rate range. In still other embodiments, when the switching temperature data includes a temperature rising rate and a switching temperature value, the AP or the MCU may determine a switching temperature threshold value (i.e., an upper limit value of a temperature range) corresponding to the temperature rising rate, where the greater the temperature rising rate, the smaller the switching temperature threshold value corresponding thereto. Therefore, when the temperature rising rate is high, the target MOS switch can be turned off as early as possible, and the charging safety is ensured.

And D3, after a preset time interval, the AP or the MCU turns on the target MOS switch. Or the temperature detection module can re-detect the switch temperature data of the target MOS switch at preset time intervals. And under the condition that the switch temperature data is in the normal value range of the temperature data, the AP or the MCU conducts the target MOS switch.

In some embodiments, the AP or the MCU may be preset with a correspondence between the switch temperature data and the cooling time value, and after acquiring the switch temperature data, the cooling time value corresponding to the switch temperature data may be determined, and then the target MOS switch is turned on again after the cooling time value is spaced. The higher the switching temperature data is, the larger the corresponding cooling time value is, so that the cooling time value can be flexibly adjusted according to the overheat degree of the target MOS switch. Thereby giving consideration to the charging efficiency and the safety of the tablet computer.

In some embodiments, the AP or MCU may generate a pulsed control signal to control the target MOS switch to intermittently turn on in the event that the switch temperature data exceeds the first data threshold and is less than the second data threshold (at which point an over-temperature fault may be determined to occur with the target MOS switch). And under the condition that the switch temperature data exceeds a second temperature threshold value (at the moment, the target MOS switch can be determined to have an overtemperature fault), the AP or the MCU controls the target MOS switch to be disconnected. Therefore, when the temperature of the target MOS switch is higher, the problem of the target MOS switch can be reduced while the charging efficiency is considered by the mode of conducting the target MOS switch at intervals, and the target MOS switch is turned off to rapidly cool the target MOS switch under the condition that the mode cannot be effectively cooled.

Alternatively, the duty cycle of the pulsed control signal may be a fixed value or may be adjusted accordingly based on the switching temperature data. For example, the higher the switching temperature data, the lower the duty cycle of the pulsed control signal to increase the switch off duration as the switching temperature increases. For example, when the switch temperature data is the first temperature data, the pulsed control signal is a first duty cycle; when the switch temperature data is second temperature data, the pulse control signal is of a second duty ratio, the first temperature data is smaller than the second temperature data, and the first duty ratio is larger than the second duty ratio.

The applicant considers that the integration of the MOS switch can increase the heating problem of the MOS tube, and through the steps D1 to D3, the wireless charging process can be adjusted in real time according to the heating degree of the MOS tube in the wireless charging process, so that the charging efficiency and the equipment safety are both considered.

It will be appreciated that electronic devices, such as tablet computers, for implementing the above-described functions, include corresponding hardware and/or software modules that perform the respective functions. The present application can be implemented in hardware or a combination of hardware and computer software, in conjunction with the example algorithm steps described in connection with the embodiments disclosed herein. Whether a function is implemented as hardware or computer software driven hardware depends upon the particular application and design constraints imposed on the solution. Those skilled in the art may implement the described functionality using different approaches for each particular application in conjunction with the embodiments, but such implementation decisions should not be interpreted as causing a departure from the scope of the present application.

In one example, FIG. 19 shows a schematic block diagram of an apparatus 1900 according to an embodiment of the application. The apparatus 1900 may include: processor 1901 and transceiver/transceiver pin 1902, and optionally, memory 1903.

The various components of device 1900 are coupled together by bus 1904, where bus 1904 includes, in addition to a data bus, a power bus, a control bus, and a status signal bus. For clarity of illustration, however, the various buses are referred to in the figures as bus 1904.

Alternatively, the memory 1903 may be used for instructions in the foregoing method embodiments. The processor 1901 may be used to execute instructions in the memory 1903 and control the receive pin to receive signals and the transmit pin to transmit signals.

The apparatus 1900 may be an electronic device or a chip of an electronic device in the above-described method embodiments.

All relevant contents of each step related to the above method embodiment may be cited to the functional description of the corresponding functional module, which is not described herein.

The steps executed by the tablet personal computer in the wireless charging control method provided by the embodiment of the application can also be executed by a chip system included in the tablet personal computer, wherein the chip system can include a processor and a bluetooth chip. The chip system may be coupled to the memory such that the chip system, when running, invokes the computer program stored in the memory, implementing the steps performed by the tablet computer. The processor in the chip system can be an application processor or a non-application processor.

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

Claims

1. A wireless charging circuit, characterized in that the wireless charging circuit is applied to a first electronic device, and the wireless charging circuit comprises:

a first transmitting coil;

A second transmitting coil;

A wireless transmitting chip, comprising a processing circuit, a first MOS switch and a second MOS switch; wherein the processing circuit is used to obtain a battery voltage of the first electronic device and generate an AC voltage according to the battery voltage; the processing circuit is connected to the first transmitting coil through the first MOS switch, and the processing circuit is connected to the second transmitting coil through the second MOS switch;

Specifically, when the first MOS switch is turned on and the second MOS switch is turned off, the first transmitting coil is used to wirelessly charge the second electronic device according to the AC voltage; when the second MOS switch is turned on and the first MOS switch is turned on, the second transmitting coil is used to wirelessly charge the third electronic device according to the AC voltage.

2. The wireless charging circuit according to claim 1, characterized in that:

The first MOS switch and the second MOS switch are PMOS tubes;

The wireless transmitting chip includes a first controller, which is used to: in a first control stage, output a first control signal to the control end of the first MOS switch to control the first MOS switch to be turned on; and in a second control stage, output the first control signal to the control end of the second MOS switch to control the second MOS switch to be turned on.

3. The wireless charging circuit according to claim 1, characterized in that:

The first MOS switch and the second MOS switch are NMOS tubes;

The wireless transmission chip includes a first controller and a bootstrap circuit.

The bootstrap circuit is used to increase the first control signal output by the first controller from a first level value to a second level value;

The first controller is used to: in a first control stage, output the first control signal of the second level value to the control end of the first MOS switch to control the first MOS switch to be turned on; and in a second control stage, output the first control signal of the second level value to the control end of the second MOS switch to control the second MOS switch to be turned on.

4. The wireless charging circuit according to claim 2 or 3, characterized in that the wireless charging circuit further comprises a second controller,

The second controller is used to obtain a first detection signal sent by the first detection sensor and a second detection signal sent by the second detection sensor; and, in response to the first detection signal and the second detection signal, when it is determined that the first MOS switch is turned on, a notification signal is sent to the first controller, wherein the notification signal is used to notify the first controller to control the first MOS switch to be turned on; and, when it is determined that the second MOS switch is turned on, a notification signal is sent to the first controller, wherein the notification signal is used to notify the first controller to control the second MOS switch to be turned on;

The first detection signal indicates that the second electronic device is placed at a first preset position of the first electronic device, and the second detection signal indicates that the third electronic device is placed at a second preset position of the first electronic device.

5. The wireless charging circuit according to claim 2 or 3, characterized in that the wireless transmitting chip comprises:

a first output port, the first output port being connected to one end of the first transmitting coil and one end of the second transmitting coil respectively, wherein the first output port is connected to a first output end of the processing circuit, and a second output end of the processing circuit is connected to a first connection end of the first MOS switch and a first connection end of the second MOS switch respectively;

a second output port, the second output port being connected to the other end of the first transmitting coil, wherein the second output port is connected to a second connection end of the first MOS switch;

A third output port, the third output port is connected to the other end of the second transmitting coil, wherein the third output port is connected to the second connection end of the second MOS switch.

6. The wireless charging circuit according to claim 1 is characterized in that the wireless charging circuit also includes a second controller, and the second controller is used to: in a first control stage, output a first control signal to the control end of the first MOS switch to control the first MOS switch to be turned on; and in a second control stage, output the first control signal to the control end of the second MOS switch to control the second MOS switch to be turned on.

7. The wireless charging circuit according to claim 6, wherein the wireless transmitting chip further comprises:

a first control port, the first control port being connected to a first output terminal of the second controller, wherein the first control port is connected to a control terminal of the first MOS switch;

A second control port, the second control port is connected to the second output terminal of the second controller, wherein the second control port is connected to the control terminal of the second MOS switch.

8. The wireless charging circuit according to claim 1, wherein the first electronic device is used to wirelessly charge the second electronic device and the third electronic device with a first power, and the first power is less than a preset power threshold.

9. The wireless charging circuit according to claim 8, characterized in that:

The value range of the first power is [1W, 5W].

10. The wireless charging circuit according to claim 1, characterized in that:

The second electronic device and the third electronic device are accessories of the first electronic device;

In the case where the first electronic device includes a tablet computer, the second electronic device is an electronic stylus pen, and the third electronic device is a wireless keyboard;

In the case where the first electronic device includes an earphone box, the second electronic device is a left earphone, and the third electronic device is a right earphone.

11. A wireless charging circuit, characterized in that the wireless charging circuit is applied to a first electronic device, and the wireless charging circuit comprises:

a first transmitting coil;

A second transmitting coil;

a first MOS switch connected to the first transmitting coil;

A second MOS switch, wherein the second MOS switch is connected to the second transmitting coil, wherein the first MOS switch and the second MOS switch are NMOS tubes;

A wireless transmitting chip, comprising a processing circuit, a bootstrap circuit, and a first controller; wherein the processing circuit is used to obtain a battery voltage of the first electronic device, and to generate an AC voltage according to the battery voltage; the processing circuit is connected to the first transmitting coil via the first MOS switch, and the processing circuit is connected to the second transmitting coil via the second MOS switch; the bootstrap circuit is used to increase a first control signal output by the first controller from a first level value to a second level value; the first controller is used to control the first MOS switch or the second MOS switch to be turned on using the first control signal of the second level value;

12. A wireless transmission chip, characterized in that it is applied to a first electronic device, and the wireless transmission chip comprises:

a processing circuit, configured to obtain a battery voltage of the first electronic device and generate an AC voltage according to the battery voltage;

a first MOS switch, wherein a first connection end of the first MOS switch is connected to the processing circuit, and a second connection end of the first MOS switch is used to connect to a first transmitting coil of the first electronic device;

a second MOS switch, wherein a first connection end of the second MOS switch is connected to the processing circuit, and a second connection end of the second MOS switch is used to connect to a second transmitting coil of the first electronic device;

13. The wireless transmission chip according to claim 12, characterized in that:

The first MOS switch and the second MOS switch are PMOS tubes;

14. The wireless transmission chip according to claim 12, characterized in that:

The first MOS switch and the second MOS switch are NMOS tubes;

15. An electronic device, comprising:

The wireless charging circuit according to any one of claims 1 to 10, or the wireless charging circuit according to claim 11.

16. A wireless charging system, comprising:

A first electronic device, wherein the first electronic device comprises the wireless charging circuit according to any one of claims 1 to 10 or the wireless charging circuit according to claim 11;

a second electronic device, the second electronic device comprising a first receiving coil, a first charging control circuit, and a first battery; the first receiving coil is arranged corresponding to the first transmitting coil, the first receiving coil is used to receive a first magnetic field signal sent by the first transmitting coil, and to generate a first alternating current according to the first magnetic field signal; the first charging control circuit is used to charge the first battery according to the first alternating current;

A third electronic device, the third electronic device includes a second receiving coil, a second charging control circuit, and a second battery; the second receiving coil is arranged corresponding to the second transmitting coil, the second receiving coil is used to receive a second magnetic field signal sent by the second transmitting coil, and generate a second alternating current according to the second magnetic field signal; the second charging control circuit is used to charge the second battery according to the second alternating current.

17. The wireless charging system according to claim 16, characterized in that:

Wherein, in the case where the first electronic device includes a tablet computer, the second electronic device is an electronic stylus pen, and the third electronic device is a wireless keyboard;