WO2022067701A1 - Charging circuit and electronic device - Google Patents

Abstract

Disclosed in the present application are a charging circuit and an electronic device. The charging circuit comprises: four switch tubes connected in series, i.e., a first switch tube, a second switch tube, a third switch tube, and a fourth switch tube, a first capacitor, a second capacitor, and a first inductor; a first end of the first switch tube is connected to a power supply end, and both ends of the first capacitor are connected to a second end of the first switch tube and a second end of the third switch tube; a second end of the second switch tube is grounded by means of the second capacitor; the second end of the first switch tube is connected to a first end of the first inductor, and a second end of the first inductor serves as a charging output end to charge a battery of the electronic device. The charging circuit increases the integration level, and the area and volume occupied by the circuit can be reduced after the integration level is increased, thereby improving the charging efficiency. When the electronic device is a PC, fast charging performance is improved. When the electronic device is a terminal, the organic combination of open-loop fast charging and closed-loop fast charging is achieved, and the organic combination of boost and buck is also achieved, thereby improving universality and allowing for compatibility with different adapters.

Description

A charging circuit and electronic equipment technical field

The present application relates to the field of electronic technology, and in particular, to a charging circuit and an electronic device.

Background technique

At present, more and more electronic devices require fast charging, that is, fast charging, especially for mobile terminals such as mobile phones. With the increase in the frequency of use, fast charging has become a standard configuration for mobile phones. At present, the charging process of electronic devices includes a constant current (CC, Constant Current) charging stage and a constant voltage (CV, Constant Voltage) charging stage. Most of the fast charging circuits inside the mobile phone use switched capacitor (SC, Switch Capacitor) circuits. Since the SC circuit is an open-loop regulation, the charging efficiency is high. Because the SC circuit has no closed-loop regulation capability, the adapter needs to regulate its own output voltage to obtain a suitable charging current for the SC circuit. The SC circuit can only work in the CC charging stage at present, and a closed-loop voltage regulation circuit needs to be used in the CV charging stage.

In the following, a mobile phone is used as an example for introduction. Referring to FIG. 1 , the figure is a schematic diagram of a fast charging system located inside a mobile phone provided in the prior art. In the CC charging stage, the output voltage Vbus of the adapter charges the battery Vbat of the mobile phone through the SC circuit 10 . In the CV charging stage, the output voltage Vbus of the adapter charges the battery through the closed-loop voltage regulator circuit 20 . The closed-loop voltage regulating circuit 20 includes Buck or Boost. When the battery of the mobile phone is a single cell, use the Buck to charge the battery. When the phone's battery is dual, select Boost to charge the battery. When the adapter is not online, that is, when Vbus has no input power, Vbat directly supplies power to the system SYS inside the mobile phone through the closed switch BATFET.

As can be seen from Figure 1, the current fast charging circuit of electronic devices such as mobile phones includes two independent parallel circuits. Different charging circuits are used to charge the battery in the CC and CV stages. The structure is relatively complex and it is difficult to achieve high integration.

Application content

The present application provides a charging circuit and electronic equipment, which can realize high integration of the fast charging circuit, and have a simple structure and easy implementation.

An embodiment of the present application provides a charging circuit, including the following four switch tubes connected in series in sequence: a first switch tube, a second switch tube, a third switch tube, and a fourth switch tube, and further comprising: a first capacitor, a second capacitor and the first inductance; the first end of the first switch tube is used to connect to the power supply terminal, and the two ends of the first capacitor are respectively connected to the second end of the first switch tube and the first end of the third switch tube Two terminals; the second terminal of the second switch is grounded through the second capacitor; the second terminal of the first switch is connected to the first terminal of the first inductor, and the second terminal of the first inductor is connected to the ground. The terminal is used as the charging output terminal to charge the battery of the electronic device.

The charging circuit provided by the embodiment of the present application integrates the advantages of high efficiency of the SC circuit, and also integrates the advantages of the closed-loop control of the Buck circuit that can stabilize voltage, and integrates the functions of the open-loop transformer circuit and the closed-loop transformer circuit. First, the high integration of the charging circuit is realized, and the structure is simple and easy to realize. Therefore, the charging circuit can improve the charging efficiency, thereby realizing fast charging in the PC scene.

Preferably, in order to prevent the current of the power supply end of the system from flowing to the power supply end, the charging circuit further includes: a reverse flow prevention switch, that is, the first end of the first switch is connected to the power supply through the reverse flow prevention switch. In addition, there is a fifth switch tube; the second end of the first inductor is connected to the system power supply end of the electronic device through the fifth switch tube.

Preferably, for a charging scenario where the hybrid power supply is boosted, the charging circuit can implement a step-down charging mode, and the first end of the first switch tube is connected to the system power supply end of the electronic device; the controller is also used for When using the power terminal to charge the battery, the first switch tube and the third switch tube are controlled to operate synchronously, the second switch tube and the fourth switch tube are controlled to operate synchronously, and the first switch tube and the fourth switch tube are controlled to operate synchronously. The actions of a switch tube and the second switch tube are opposite.

Preferably, for the narrow-voltage DC charging scenario, the charging circuit further includes: a reverse-flow prevention switch and a charge-discharge control switch; similarly, the reverse-flow prevention switch is to prevent other currents from flowing in the reverse direction to the power supply, so as to achieve shutdown function. The first end of the first switch tube is connected to the power supply terminal through the anti-reverse flow switch tube; the second end of the first inductor is connected to the battery through the charge and discharge control switch tube; the first The second end of the inductor is connected to the system power supply end of the electronic device.

Preferably, the charging circuit can realize the Buck step-down charging mode under the control of the controller, that is, the controller controls the first switch tube and the third switch when charging the battery by using the step-down voltage of the power supply terminal. The switches operate synchronously to control the second switch and the fourth switch to operate synchronously, and the first switch and the second switch operate oppositely.

Preferably, the charging circuit provided in the embodiment of the present application can also implement boost charging, that is, the Boost working mode, and further includes: a sixth switch tube; the first end of the sixth switch tube is connected to the third switch tube of the third switch tube. Two terminals, the second terminal of the sixth switch tube is connected to the second terminal of the first inductor; the controller is further configured to control the battery when the power supply terminal is boosted to charge the battery Both the second switch tube and the third switch tube are disconnected, the first switch tube and the fourth switch tube are controlled to act synchronously, and the actions of the first switch tube and the sixth switch tube are controlled to be opposite. This charging circuit is suitable for the scenario where the battery is two batteries connected in series, and needs to be boosted to charge the batteries connected in series.

Based on the charging circuit provided by the above embodiment, the embodiment of the present application further provides an electronic device, including: a battery and the charging circuit described above; a first end of the charging circuit is used for connecting to a power source, and a first end of the charging circuit The two ends are connected to the power supply terminal of the battery; the charging circuit is used for converting the electric energy provided by the power supply terminal to charge the battery. For example, the electronic device may be a PC.

The embodiment of the present application also provides a charging mode control method, including: obtaining a priority charging mode, and if it is a performance priority charging mode, configuring the voltage of the adapter to a maximum value; if it is a fast charging priority mode, dynamically adjusting according to the voltage of the battery The voltage of the adapter performs.

Therefore, the charging control method provided by the embodiments of the present application can maximize the balance of system performance and charging performance, and the controller can select a control strategy as required.

In addition, the embodiment of the present application further provides another charging mode control method, which includes: detecting the type of the adapter and the maximum output voltage of the Vbus terminal. When the maximum voltage of the adapter is greater than the battery voltage, the charging mode configured with the charging circuit is a step-down charging mode; when the maximum voltage of the adapter is less than the battery voltage, the charging mode configured with the charging circuit is a boost charging mode.

In addition, the embodiments of the present application further provide a computer-readable storage medium, including instructions or computer programs, which, when executed on a computer, cause the computer to execute the charging control method described above.

From the description of the above embodiments, those skilled in the art can clearly understand that all or part of the steps in the methods of the above embodiments can be implemented by means of software plus a general hardware platform. Based on this understanding, the technical solution of the present application can be embodied in the form of a software product, and the computer software product can be stored in a storage medium, such as read-only memory (English: read-only memory, ROM)/RAM, magnetic disk, An optical disc, etc., includes several program codes or instructions for making a computer device (which may be a personal computer, a server, or a network communication device such as a router) to execute the methods described in various embodiments or some parts of the embodiments of the present application.

An embodiment of the present application further provides a charging circuit, including: a first switch tube, a second switch tube, a third switch tube, a fourth switch tube, a first capacitor and a first inductor; a first switch tube of the first switch tube The terminal is used to connect the power terminal, the second end of the first switch tube is connected to the first end of the second switch tube, and the second end of the second switch tube is connected to the first end of the third switch tube , the second end of the third switch tube is connected to the first end of the fourth switch tube, the second end of the fourth switch tube is grounded; the two ends of the first capacitor are respectively connected to the first switch The second end of the second switch tube and the second end of the third switch tube; the second end of the second switch tube is used as the first output end for charging the battery of the first electronic device; the first switch tube The second end of the first inductor is connected to the first end of the first inductor, or the second end of the third switch is connected to the first end of the first inductor, and the second end of the first inductor is used as the second The output terminal supplies power to the load of the first electronic device.

When the charging circuit has two output terminals, it can be applied to scenarios such as terminal equipment and wearable devices. Since the charging circuit has two output terminals, it can charge two electronic devices at the same time. For example, when the load of the first electronic device is a second electronic device, the second output terminal is used to charge the second electronic device; for example, the first electronic device is an earphone box, the second electronic device is an earphone, and the earphone is located in the earphone When the box is installed, the earphone acts as the load of the earphone box. In the case of the earphone box, the battery of the earphone box charges the earphone. The charging circuit provided in this embodiment can be applied to mobile terminals and wearable devices, realizes high integration of fast charging, and realizes the effective integration of closed-loop transformer circuits and open-loop transformer circuits. High efficiency, and can use the voltage regulation function of the closed-loop transformer circuit, which can be applied to both single-cell batteries and dual-cell batteries, and has a wide range of application scenarios, which improves the universality of the charging circuit. Moreover, when the adapter is not connected, the first electronic device can also use the power of its own battery to charge the second electronic device

Preferably, the charging circuit can realize open-loop charging, that is, open-loop fast charging, and the charging efficiency can be improved at the same time of fast charging. The open-loop fast charging is suitable for mobile phone scenarios and earphone box scenarios. The controller controls the first switch tube and the third switch tube to operate synchronously, and controls the second switch tube and the The four switches operate synchronously, and the actions of the first switch and the second switch are opposite.

Preferably, the charging circuit further includes: a controller and a fifth switch tube; the first end of the fifth switch tube is connected to the second end of the first inductor, and the second end of the fifth switch tube is connected to the the first output terminal; the controller is further configured to control the second switch tube to turn off, control the fifth switch tube to turn on, and control the first switch tube and the first switch tube during the closed-loop charging stage. The three switches operate synchronously, and the actions of the first switch and the fourth switch are controlled to be opposite. The charging mode is a closed-loop step-down charging mode.

Preferably, it also includes: a controller and a fifth switch; the first end of the fifth switch is connected to the second end of the first inductor, and the second end of the fifth switch is connected to the first an output end; the controller is further configured to control the second switch tube to turn off, control the fifth switch tube to turn on, and control the first switch tube and the fourth switch tube during the closed-loop charging stage The switch tubes act synchronously, and the first switch tube and the third switch tube are controlled to have opposite actions. The charging mode is a closed-loop boost charging mode.

Preferably, when the load of the first electronic device is the second electronic device, the second output terminal is used for charging the second electronic device; the controller is also used for increasing the voltage of the battery When charging the second electronic device after boosting, the second switch tube and the fourth switch tube are controlled to operate synchronously, and the second switch tube and the third switch tube are controlled to operate oppositely. For example, when the application scenario is an earphone box, the first electronic device is an earphone box, the second electronic device is an earphone, and the earphone box uses the voltage of its own battery to charge the earphone.

Preferably, the following describes the Buck+ switched capacitor SC charging mode. When the second end of the first switch is connected to the first end of the first inductor, it further includes: a reverse-flow prevention switch and an eighth switch; The first end of the first switch tube is connected to the power supply terminal through the anti-reflux switch tube; the first end of the eighth switch tube is used to connect to the power supply terminal, and the second end of the eighth switch tube is used to connect to the power supply terminal. The terminal is connected to the second output terminal.

Preferably, it further includes: a controller; the controller is configured to control the anti-reverse flow switch to be turned on and to control the eighth switch to be turned off in the open-loop charging stage; in the closed-loop charging stage, control all The eighth switch tube is turned on, and the backflow prevention switch tube is controlled to be disconnected.

Preferably, open-loop charging scenarios applicable to both mobile phones and earphones, and single-battery charging scenarios are described below. The controller is further configured to control the synchronous action of the first switch tube and the third switch tube during the open-loop charging stage, and control the synchronous action of the second switch tube and the fourth switch tube, so that the The actions of the first switch tube and the second switch tube are opposite.

Preferably, the controller is further configured to control the second switch transistor and the fourth switch transistor to operate synchronously, and control the second switch transistor and the third switch transistor during the closed-loop charging stage action is the opposite.

Preferably, when the load of the first electronic device is the second electronic device, the second output terminal is used to charge the battery of the second electronic device; the controller is further configured to use the When the battery is charging the second electronic device, the second switch tube and the fourth switch tube are controlled to operate synchronously, and the second switch tube and the third switch tube are controlled to operate oppositely. This scenario is applicable when the battery of the first electronic device charges the second electronic device when the power supply terminal is not connected to the adapter, for example, the earphone box charges the earphone, and the charging mode is a boost charging mode.

Preferably, the following describes the case where the two output ends are the second end of the second switch tube and the second end of the third switch tube, when the second end of the third switch tube is connected to the first end of the first inductor When the reverse flow prevention switch tube is used, it also includes: a reverse flow prevention switch tube and a ninth switch tube; the first end of the first switch tube is used for connecting the power supply terminal through the reverse flow prevention switch tube; the second switch tube of the first inductor The terminal is connected to the power terminal through the ninth switch tube. In this charging scenario, the power supply terminal directly supplies power to the second output terminal, that is, charging, without any power conversion, so that the charging efficiency can be improved.

Preferably, the method further includes: a controller; the controller is configured to control the conduction of the reverse-flow prevention switch tube and control the ninth switch tube to be turned off in the open-loop charging stage; and in the closed-loop charging stage, control all The ninth switch tube is turned on or periodically turned on, and the anti-reverse flow switch tube is controlled to be turned off.

Preferably, an open-loop step-down charging mode suitable for earphone boxes and mobile phones is described below. The controller is further configured to control the first switch transistor and the third switch transistor to operate synchronously, and control the second switch transistor and the fourth switch transistor to operate synchronously during the open-loop charging stage , the actions of the first switch tube and the second switch tube are opposite.

Preferably, a closed-loop boost charging mode suitable for the earphone box is introduced below. The controller is further configured to control the first switch tube and the third switch tube to act synchronously during the closed-loop charging stage, and control the The second switch tube and the fourth switch tube act synchronously, and the actions of the first switch tube and the second switch tube are controlled to be opposite.

Preferably, when the power supply terminal is not connected to the adapter, for example, in the charging scenario of the earphone box, the mode in which the earphone box reduces the voltage to charge the earphone is described below. When the load of the first electronic device is the second electronic device; the controller is further configured to use the battery to charge the second electronic device, and control the first switch tube and the third electronic device The switches operate synchronously, control the synchronous operations of the second switch and the fourth switch, and control the first switch and the second switch to operate oppositely.

Preferably, it is described below that the charging circuit can work in the charging mode of BuckBoost+SC, and further includes: a tenth switch; the first end of the tenth switch is connected to the second end of the first inductor; The second end of the ten switch tubes is grounded.

Preferably, the controller is further configured to control the ninth switch transistor to be periodically turned on during the closed-loop step-down charging stage, and control the controller to turn on the ninth switch transistor and the tenth switch transistor alternately, The fourth switch tube is controlled to be turned off, and the third switch tube is controlled to be turned on.

Preferably, the controller is further configured to control the ninth switch transistor to be periodically turned on, and control the first switch transistor, the third switch transistor, and the tenth switch transistor in the closed-loop buck-boost charging stage Synchronous action controls the synchronous action of the second switch tube, the fourth switch tube and the ninth switch tube.

Preferably, the charging scenario of forward and reverse BuckBoost+SC is described below, and further includes: an eleventh switch tube; the first end of the eleventh switch tube is connected to the second end of the first inductor, and the tenth switch tube is connected to the second end of the first inductor. The second end of a switch tube is used as the second output end; the controller is further configured to control the eleventh switch tube and the fourth switch tube to act synchronously.

Preferably, the controller is further configured to control the synchronous action of the first switch tube and the third switch tube, control the synchronous action of the second switch tube and the fourth switch tube, the first switch tube The actions of the tube and the second switch tube are opposite, and the tenth switch tube is controlled to act synchronously with the third switch tube, and the eleventh switch tube is controlled to be synchronized with the fourth switch tube.

Preferably, a simplified control strategy is introduced below. First, the step-down charging control in the simplified control strategy is introduced. The tenth switch tube is turned off, and the eleventh switch tube is controlled to be turned on; the first switch tube and the third switch tube are controlled to operate synchronously, and the second switch tube and the fourth switch tube are controlled Synchronous action, controlling the actions of the first switch tube and the second switch tube to be opposite.

Preferably, the boost charging control in the simplified control strategy is described below. The controller is further configured to control the first switch tube, all The second switch tube and the fourth switch tube are both turned off, the third switch tube is controlled to be turned on, and the tenth switch tube and the eleventh switch tube are controlled to be turned on alternately.

An embodiment of the present application further provides an electronic device, including: a battery and the charging circuit described above; a first end of the charging circuit is used to connect to a power supply end, and a first output end of the charging circuit is used to connect to the battery ; the second output terminal of the charging circuit is used to connect the load of the electronic device; the charging circuit is used to convert the electric energy provided by the power supply terminal to charge the battery, and is used for charging the battery of the electronic device. load power supply. For example, the electronic device is a mobile terminal such as a mobile phone, or for example, the electronic device is a wearable device such as an earphone box.

It should be noted that the controller in the above embodiments to control the actions of each switch tube means that the controller sends a control signal, such as a pulse width modulated PWM signal, to the control terminal of each switch tube.

As can be seen from the above technical solutions, the embodiments of the present application have the following advantages:

When the charging circuit has one output terminal, that is, the second terminal of the first switch tube is used as the output terminal, the charging circuit integrates the advantages of high efficiency of the SC circuit and the advantages of the closed-loop control of the Buck circuit that can stabilize voltage. The functions of the open-loop transformer circuit and the closed-loop transformer circuit are integrated into one, which realizes the high integration of the charging circuit, and has a simple structure and is easy to implement. Therefore, the charging circuit provided in this embodiment can improve the charging efficiency, thereby realizing fast charging in a PC scenario.

When the charging circuit has two output terminals, it can be applied to scenarios such as terminal equipment and wearable devices. Since the charging circuit has two output terminals, it can charge two electronic devices at the same time. For example, when the load of the first electronic device is the second electronic device, the second output terminal is used to charge the second electronic device; the charging circuit provided in this embodiment can be applied to mobile terminals and wearable devices, and realizes fast The high integration of the charger realizes the effective integration of the closed-loop transformer circuit and the open-loop transformer circuit. It can not only use the high efficiency of the open-loop transformer circuit, but also use the voltage regulation function of the closed-loop transformer circuit. It can also be applied to two-cell batteries, and has a wide range of application scenarios, that is, the universality of the charging circuit is improved.

Description of drawings

1 is a schematic diagram of a fast charging system located inside a mobile phone provided by the prior art;

2 is a structural diagram of an HPB provided by an embodiment of the present application;

FIG. 3 is an NVDC architecture diagram provided by an embodiment of the present application;

FIG. 4 is a schematic diagram of Embodiment 1 of the charging circuit provided by the embodiment of the present application;

FIG. 5 is a schematic diagram of an HPB fast charging architecture provided by an embodiment of the present application;

6 is a schematic diagram of a path corresponding to FIG. 5;

Fig. 7 is another kind of route schematic diagram corresponding to Fig. 5;

FIG. 8 is a schematic diagram of an NVDC fast charging architecture provided by an embodiment of the present application;

FIG. 9 is a path diagram of NVDC fast charging and boosting provided by an embodiment of the present application;

Fig. 10 is another route diagram corresponding to Fig. 9;

11 is a flowchart of a control method in an HPB mode provided by an embodiment of the present application;

12 is a flowchart of a control method in an NVDC mode provided by an embodiment of the present application;

FIG. 13 is a schematic diagram of Embodiment 1 of an electronic device provided by an embodiment of the present application;

14 is a schematic diagram of another charging circuit provided by an embodiment of the present application;

15 is a schematic diagram of the first electronic device provided by an embodiment of the application being an earphone box;

16 is a schematic diagram of the interior of an earphone box provided by an embodiment of the application;

FIG. 17 is a schematic diagram of another charging circuit provided by an embodiment of the present application;

FIG. 18 is a path diagram of the open-loop charging stage corresponding to FIG. 17;

FIG. 19 is a path diagram of step-down in the CV charging stage corresponding to FIG. 17;

FIG. 20 is another path diagram of step-down in the CV charging stage corresponding to FIG. 17;

FIG. 21 is a path diagram of boosting voltage in the CV charging stage corresponding to FIG. 17;

FIG. 22 is another path diagram of boosting voltage in the CV charging stage corresponding to FIG. 17;

23 is a schematic diagram of another charging circuit provided by an embodiment of the present application;

FIG. 24 is a schematic diagram of yet another charging circuit provided by an embodiment of the present application;

25A is a schematic diagram of still another charging circuit provided by an embodiment of the present application;

FIG. 25B is a schematic diagram of another charging circuit based on FIG. 25A provided by an embodiment of the present application;

Figure 26 is a schematic diagram of a working mode corresponding to Figure 25B;

Fig. 27 is another working mode schematic diagram corresponding to Fig. 25B;

FIG. 28 is a path diagram when the Vbus corresponding to FIG. 25B is not connected to a power supply;

FIG. 29 is a modal diagram when Q1 and Q3 corresponding to FIG. 25B are turned on;

FIG. 30 is a modal diagram when Q1 and Q3 corresponding to FIG. 25B are turned off;

FIG. 31 is a schematic diagram showing that Q11 corresponding to FIG. 25B is turned off and Q10 is turned on;

FIG. 32 is a schematic diagram showing that Q11 corresponding to FIG. 25B is turned on and Q10 is turned off;

FIG. 33 is a schematic diagram of Embodiment 2 of an electronic device provided by an embodiment of the present application.

Detailed ways

The technical solutions in the embodiments of the present application will be described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Words such as "first" and "second" in the following description are only used for descriptive purposes, and should not be construed as indicating or implying relative importance or implying the number of indicated technical features. Thus, a feature defined as "first", "second", etc., may expressly or implicitly include one or more of that feature. In the description of this application, unless stated otherwise, "plurality" means two or more. In addition, in this application, directional terms such as "upper" and "lower" may include, but are not limited to, definitions relative to the schematic placement of components in the drawings. It should be understood that these directional terms may be relative concepts, They are used for relative description and clarification, which may vary accordingly depending on the orientation in which the components are placed in the drawings.

In this application, unless otherwise expressly specified and limited, the term "connection" should be understood in a broad sense. For example, "connection" may be a fixed connection, a detachable connection, or an integral body, indicating a communication connection or an electrical connection ; It can be directly connected by wire or indirectly connected through an intermediate medium. Furthermore, the term "coupled" may be a manner of electrical connection that enables signal transmission. "Coupling" can be a direct electrical connection or an indirect electrical connection through an intermediate medium.

In order to enable those skilled in the art to better understand the technical solutions provided by the embodiments of the present application, the following first takes the scenario of fast charging of the battery of a computer PC as an example for introduction. According to the different adapters of the computer, the structure of the charging circuit inside the computer is different. At present, it mainly includes the following two categories: the first category: Hybrid Power Boost (HPB, Hybrid Power Boost) mode; the second category: narrow voltage DC charging (NVDC, Narrow Voltage Direct Current) mode;

The working principle of the first type of HPB is described below. As shown in FIG. 2 , the figure is an HPB architecture diagram provided by an embodiment of the present application. Vin is the input voltage of the charging circuit, that is, the output voltage of the adapter, and the battery Vbat is charged through the charging circuit 30 . At the same time, Vin can directly supply power to the computer's system.

The working principle of the second type of NVDC is described below. Referring to FIG. 3 , this figure is an NVDC architecture diagram provided by an embodiment of the present application. NVDC is suitable for the adjustable output voltage of the adapter, that is, the output voltage is a wide range of voltage. Vin charges the battery Vbat through the charging circuit 30 and supplies power to the computer system.

As can be seen from Figure 2 and Figure 3, whether it is HPB or NVDC, the charging circuit needs to improve the conversion efficiency of electric energy. The technical solutions provided by the embodiments of the present application are described below with reference to the schematic diagrams of the specific charging circuits, which can truly realize fast charging in PC scenarios and meet the system power supply requirements of the PCs. The embodiments of the present application provide a high-efficiency and suitable for PCs. In the charging circuit of the application scenario, taking the output voltage of the adapter as 20V as an example, the charging circuit provided by the embodiment of the present application is used to charge the battery of the PC, and the charging voltage of the battery of the PC can be satisfied when the charging circuit works at the best efficiency point According to the requirements of the battery, the charging voltage range of the PC battery is about 15V, for example, between 12V-20V. The voltage transformation ratio corresponding to the optimum efficiency point of the charging circuit provided by the embodiment of the present application is 4:3, that is, the input voltage of 20V is stepped down to about 15V. The charging circuit provided by the embodiments of the present application will be described in detail below with reference to the accompanying drawings.

The first embodiment of the charging circuit:

Referring to FIG. 4 , this figure is a schematic diagram of a charging circuit provided by an embodiment of the present application. The charging circuit provided in this embodiment includes: a first switch transistor Q1, a second switch transistor Q2, a third switch transistor Q3, a fourth switch transistor Q4, a first capacitor Cfly, a second capacitor Cmid, and a first inductor L1; The first end of a switch tube Q1 is used to connect to the adapter, namely the Vbus end in the figure, the second end of the first switch tube Q1 is connected to the first end of the second switch tube Q2, and the second end of the second switch tube Q2 is connected to The first end of the third switch tube Q3, the second end of the third switch tube Q3 is connected to the first end of the fourth switch tube Q4, and the second end of the fourth switch tube Q4 is grounded; the first capacitor Two ends of Cfly are respectively connected to the second end of the first switch tube Q1 and the second end of the third switch tube Q3; the second end of the second switch tube Q2 is grounded through the second capacitor Cmid; the first switch tube The second end of Q1 is connected to the first end of the first inductance L1, and the second end of the first inductance L1 serves as a charging output end Vout for charging the battery of the electronic device. In actual implementation, the controller outputs driving signals to Q1-Q4, which can output four channels, or use the same driving signal for switches in the same conduction state. When the charging circuit works in the step-down charging mode, in each switching cycle, the conduction states of Q1 and Q2 are opposite and complementary conduction, the conduction states of Q1 and Q3 are the same, and the conduction states of Q2 and Q4 are the same.

Specifically, when the second end of Q1 is connected to the first end of the first inductor L1, and the second end of the second inductor L1 is used as the output end, the voltage ratio of Vbus/Vbat of the charging circuit is about 4:3, therefore, When the input of the PC-compliant adapter is about 20V, it can achieve the purpose of reducing the voltage by about 15V, which can not only meet the voltage requirements of the PC, but also achieve the maximum efficiency of the charging circuit. Moreover, the charging circuit integrates the advantages of high efficiency of the open-loop SC circuit, and integrates the advantages of the Buck circuit closed-loop control and fast voltage regulation. The charging circuit is highly integrated, and the structure is simple and easy to implement. Therefore, the charging circuit provided in this embodiment can improve the charging efficiency, thereby realizing fast charging in a PC scenario.

The following describes the working principles of the Hybrid Power Boost (HPB, Hybrid Power Boost) mode and the Narrow Voltage Direct Current (NVDC, Narrow Voltage Direct Current) mode in the PC scenario. Referring to FIG. 5 , this figure is a schematic diagram of an HPB fast charging architecture provided by an embodiment of the present application. The charging circuit provided in this embodiment may further include: a backflow prevention switch RBFET and a fifth switch Q5; the first end of the first switch Q1 is connected to an adapter through the backflow prevention switch RBFET, that is, connected to Vbus ; The role of the anti-reverse switch RBFET is mainly to prevent the current from the SYS side of the system power supply from flowing to the Vbus side when it is turned off. The anti-reverse flow switch RBFET can be implemented by a switch to prevent unidirectional reverse flow. It should be noted that, when the anti-reflux switch RBFET is specifically implemented, it can also be implemented by using two back-to-back switches. In Figure 5, the anti-reflux switch RBFET is realized by connecting two switches in series, that is, in preventing When the reverse flow switch RBFET is turned off, the function of complete shutdown is realized, that is, no current flows in both directions.

The second end of the first inductor L1 is connected to the system power supply end SYS of the electronic device through the fifth switch transistor Q5. The electronic device takes a PC as an example, that is, the first end of Q5 is connected to the second end of L1, and the second end of Q5 is connected to the system power supply end SYS of the PC. The first end of the first switch tube Q1 is directly connected to the system power supply terminal SYS, that is, SYS is directly connected to Vbus through the anti-reflux switch tube RBFET, that is, when the adapter is inserted into the PC, the adapter can directly supply power to the system power supply terminal SYS of the PC, improving the power supply. efficiency. The charging circuit provided in this embodiment further includes: a controller (not shown in the figure); the controller is specifically configured to control the fifth switch tube Q5 when the adapter is connected, that is, when an external power source is connected to the Vbus Disconnected, that is, Vbat is disconnected from SYS at this time, and not connected together; when the adapter is not connected, that is, when Vbus is not connected to an external power supply, the controller controls the fifth switch tube Q5 to close, that is, Vbat is connected to SYS Together, for example, a battery in a PC powers the system power supply side of the PC. It should be noted that when Q5 is turned off, it can work in a unidirectional conduction mode, because Q5 includes a parallel diode, that is, it can be turned on from Vbat to SYS. When the product is implemented, Q1-Q4 can be integrated in one chip to implement, or can be implemented independently, which is not specifically limited in the embodiment of this application. When the battery is fully charged, when Vbus continues to connect to the adapter, it can control Q1-Q4 to be disconnected, RBFET to be closed, Q5 to be disconnected, and Vbus to directly supply power to SYS.

The working principles of the embodiments of the present application are described below with reference to the road diagram. Referring to FIG. 6 and FIG. 7 , the diagrams are the path diagrams corresponding to FIG. 5 . Among them, Figure 6 corresponds to the path diagram when Q1 and Q3 are turned on, and Q2 and Q4 are turned off. Figure 7 corresponds to the path diagram when Q1 and Q3 are turned off, and Q2 and Q4 are turned on. It can be called path 1, and path 1 is the step-down path.

The controller controls the charging circuit to work in the step-down mode, and each switch tube can be a controllable switch tube, that is, in addition to the first terminal and the second terminal, each switch tube also includes a third terminal, that is, the control terminal. For example, for MOS For the tube, the control terminal is the gate. The controller can output a drive signal to control the switching state of each switch, that is, turn on or off (turn off), and control the first switch Q1 and the third switch Q3 to act synchronously when using the adapter to charge the battery, that is, Q1 The driving signal of Q3 and Q3 can be in the same phase, and the second switch Q2 and the fourth switch Q4 can be controlled to operate synchronously. The driving signals of Q2 and Q4 can be in the same phase. The first switch Q1 and the second switch Q2 The action is reversed, that is, the drive signals of Q1 and Q2 are complementary. The synchronous action of the above switches refers to turning on and turning off at the same time. The opposite action of the switch means that when one switch is turned on, the other switch is turned off, and the two switches will not be turned on at the same time.

As can be seen from Figure 6, when both Q1 and Q3 are turned on, and Q2 and Q4 are both turned off, Vbus directly supplies power to SYS, Vbus charges Vbat through Q1 and L1, and Vbus passes through the path formed by Q1 and Q3 to Cfly, Cmid charge. As can be seen from Figure 7, when Q1 and Q3 are both turned off and Q2 and Q4 are both turned on, Vbus directly supplies power to SYS, and Cfly and Cmid charge Vbat through L1. If the duty cycle of Q1's drive signal is D, the transfer gain from Vbus to Vbat is:

Since D is less than 1, therefore, Vbus>Vbat, the charging circuit is a step-down charging circuit. The above describes the implementation process of the charging circuit provided by the embodiment of the present application in the HPB mode in the PC scenario. The following describes the implementation process of the charging circuit provided by the embodiment of the present application in the NVDC mode in the PC scenario.

Referring to FIG. 8 , this figure is a schematic diagram of an NVDC fast charging architecture provided by an embodiment of the present application. When the charging circuit provided by the embodiment of the present application is applied to the NVDC fast charging architecture, in addition to the device shown in FIG. 4 , it also includes: a reverse-flow prevention switch RBFET and a charge-discharge control switch BATFET1; wherein the reverse-flow prevention switch The RBFET may be the same as the anti-backflow switch RBFET in FIG. 5 , which is not repeated here, that is, the first end of the first switch Q1 is connected to the power supply terminal Vbus through the anti-backflow switch RBFET.

The second end of the first inductor L1 is connected to the battery through the charge-discharge control switch BATFET1, that is, connected to the charging end Vbat. The second end of the first inductor L1 is connected to the system power supply end SYS of the electronic device. It should be noted that the NVDC mode is different from the HPB mode. Comparing Figure 5 and Figure 8, it can be found that the connection relationship of SYS is different.

The charging circuit provided in this embodiment further includes: a controller (not shown in the figure); the controller is used to control the charging and discharging control switch BATFET1 to be turned on when the adapter is connected, that is, when the battery is charged by the power supply terminal Vbus ; When the battery is fully charged, the charge-discharge control switch BATFET1 is controlled to be disconnected. In this embodiment, Vbus can also supply power to SYS through Q1 and L1.

The controller is also used to control the first switch tube Q1 and the third switch tube Q3 to act synchronously when the battery is charged by the power supply terminal Vbus, that is, when the battery is charged after the voltage provided by the adapter is stepped down, to control the The second switch Q2 and the fourth switch Q4 operate synchronously, and the first switch Q1 and the second switch Q2 operate oppositely. The synchronization action and the opposite action here are the same as in the HPB mode, and are not repeated here. This mode is suitable when the voltage of the adapter is greater than the voltage of the battery, and the voltage of the adapter is stepped down to charge the battery. The working principle is similar to that of FIG.

In the following, the working principle of boost charging under the NVDC fast charging architecture will be mainly introduced in conjunction with FIG. 8 , FIG. 9 and FIG. 10 . Referring to FIG. 9 , this figure is a path diagram of the NVDC fast charging and boosting provided by the embodiment of the present application. Among them, Figure 9 is the corresponding path diagram when Q1 and Q4 are closed, and Figure 10 is the corresponding path diagram when Q1 and Q4 are turned off.

When NVDC fast charging is implemented by a booster circuit, the charging circuit further includes: a sixth switch tube Q6; the first end of the sixth switch tube Q6 is connected to the second end of the third switch tube Q3, and the sixth switch tube Q6 is connected to the second end of the third switch tube Q3. The second end of the switch tube Q6 is connected to the second end of the first inductor L1; the battery is charged after boosting the voltage of the power supply terminal Vbus, that is, the voltage of the adapter is boosted to charge the battery, which is suitable for the voltage of the adapter lower than that of the battery. Voltage, such as the output voltage of the adapter is 5V, not 20V. That is, the charging circuit provided in this embodiment can be compatible with the low-voltage adapter and charge the battery of the PC. During step-down charging, Q6 remains disconnected, that is, Q6 is equivalent to being stripped from the charging circuit and has no effect. The controller is also used to control both the second switch tube Q2 and the third switch tube Q3 to be disconnected when the battery Vbat is charged after Vbus is boosted, and control the first switch tube Q1 and the fourth switch tube Q4 to operate synchronously, The actions of controlling the first switch transistor Q1 and the sixth switch transistor Q6 are opposite.

For the convenience of subsequent description, control strategy 2 is introduced. Control strategy 2 refers to: Q2 and Q3 remain disconnected, Q1 and Q4 act synchronously, the driving pulses of Q1 and Q6 are inverted, and the duty cycle of Q1 conduction is D. As shown in Figure 9, Q1 and Q4 are turned on, Q6 is opposite to Q1, Q6 is turned off, Vbus charges Vbat through Q1 and L1, and at the same time supplies power to SYS and charges Cfly. The current path iL can see the direction of the current.

As shown in Figure 10, Q1 and Q4 are turned off, Cfly discharges to charge Vbat, and supplies power to SYS at the same time, the current path iL can see the direction of the current. When the duty cycle of the driving signal of Q1 is D, the gain of the charging circuit is as follows:

That is, the voltage range of Vbat is (Vin, +∞), which realizes closed-loop boost conversion.

In addition, the charging circuit can also work in reverse, that is, when the power supply terminal Vbus is not connected to an adapter, the battery is used as the power supply to supply power, that is, Vbat is used as the input terminal of the power supply, and Vbus is used as the output terminal. The reverse gain of the charging circuit is:

That is, the output voltage range of Vbus is (0, Vbat), which realizes closed-loop step-down conversion.

It should be noted that when the adapter is not connected, that is, when the adapter is not in place, there is no external power input at the Vbus end. Vbus can be used as a power output end of the computer. For example, the battery of the PC can be used to power the mouse, that is, Vbat outputs power to Vbus. .

The HPB fast charging architecture provided by the above embodiments is generally applicable to the adapter whose output is a fixed voltage, that is, the fixed voltage of the adapter is greater than the battery voltage. Therefore, the charging circuit operates in a step-down mode to fast charge the battery. The NVDC fast charging architecture provided in this embodiment is compatible with different situations of the adapter, and can work in both the buck mode and the boost mode. The control method corresponding to the charging circuit provided by the embodiments of the present application will be described in detail below with reference to the accompanying drawings. The above charging circuit provided by the embodiment of the present application can also select its charging control strategy, and can work in a performance priority charging mode or a fast charging priority mode.

Referring to FIG. 11 , which is a flowchart of a charging control method provided by an embodiment of the present application. The control method provided by this embodiment includes: S1101: obtain the priority charging mode, if it is the performance priority charging mode, execute S1102; if it is the fast charging priority mode, execute S1103; S1102: configure the voltage of the adapter to the maximum value; S1103: according to The voltage of the battery dynamically adjusts the voltage of the adapter. Therefore, the control method provided by the embodiments of the present application can maximize the balance of system performance and charging performance, and the controller can select a control strategy as required.

The controller may be implemented by an application processor (AP, Application Processor), other processors, or a logic control circuit, which is not specifically limited in the embodiments of the present application, as long as the above charging process can be completed. control of the circuit. The controller may comprise hardware or a combination of hardware and software.

The following describes the control strategy, ie, the control method, of the NVDC fast charging architecture of the PC. Referring to FIG. 12 , this figure is a flowchart of the control method in the NVDC mode provided by the embodiment of the present application. S1201: Detect the type of the adapter and the maximum output voltage of the Vbus terminal. During specific implementation, the PC can communicate with the adapter through handshake communication through a communication protocol, and learn the type of the adapter and the maximum voltage that the adapter can output.

S1202: When the maximum voltage of the adapter is greater than the battery voltage, the charging mode of the charging circuit is set to step-down charging mode; for example, the output voltage of the adapter is about 20V, which is greater than the voltage of the battery. Therefore, the charging circuit is configured as Buck step-down mode. Charge the battery.

S1203: When the maximum voltage of the adapter is less than the battery voltage, configure the charging mode of the charging circuit as a boost charging mode. For example, the output voltage of the adapter is about 5V, which is less than the voltage of the battery. Therefore, the charging circuit is configured to Boost boost mode to charge the battery. The type of each switch tube in the charging circuit provided by the above embodiments of the present application is not specifically limited, for example, it may be implemented by a MOS tube, for example, Q1-Q4 may be an NMOS tube. The gate of the MOS tube is used to receive the control signal of the controller, such as the PWM signal output by the controller.

Specifically, the controller may include a processor and a memory. The memory is a computer-readable storage medium, so the embodiments of the present application also provide a computer-readable storage medium, including instructions or computer programs that, when executed on a computer or a controller, cause the computer or the controller to execute the above descriptions The charging control method of FIG. 11 and FIG. 12 , that is, the method steps introduced in FIG. 11 and FIG. 12 will not be repeated here. The computer instructions are also a computer program product. . The processor includes but is not limited to CPU (Central Processing Unit, Central Processing Unit), GPU (Graphics Processing Unit, Graphics Processing Unit) or DSP (Digital Signal Processor, Digital Signal Processing) and the like.

From the description of the above embodiments, those skilled in the art can clearly understand that all or part of the steps in the methods of the above embodiments can be implemented by means of software plus a general hardware platform. Based on this understanding, the technical solution of the present application can be embodied in the form of a software product, and the computer software product can be stored in a storage medium, such as read-only memory (English: read-only memory, ROM)/RAM, magnetic disk, An optical disc, etc., includes several program codes or instructions for making a computer device (which may be a personal computer, a server, or a network communication device such as a router) to execute the methods described in various embodiments or some parts of the embodiments of the present application.

In addition, an embodiment of the present application further provides an apparatus, including a plurality of units, each unit is configured to perform the corresponding steps of the previous embodiments, such as the method steps introduced in FIG. 11 and FIG. 12 . The multiple units are functional units, and may be implemented in software, hardware, or a combination of hardware and software, which is not limited in this embodiment.

Electronic device embodiment 1:

Based on the charging circuit provided by the above embodiment, the embodiment of the present application further provides an electronic device, the electronic device includes the charging circuit provided by the above embodiment, and also includes a battery. Referring to FIG. 13 , this figure is a schematic diagram of Embodiment 1 of the electronic device provided by the embodiment of the present application. The electronic device provided in this embodiment may be, for example, a PC, and the electronic device may include the charging circuit 1000 described in the above embodiment, which may be either a charging circuit in an HPB fast charging mode or a charging circuit in an NVDC fast charging mode.

The first end of the charging circuit 1000 is connected to an adapter, and the second end of the charging circuit 1000 is connected to the power end of the battery 2000; when the electronic device is a PC, the battery is the battery of the PC. The charging circuit 1000 is used for charging the battery 2000 after converting the electrical energy provided by the adapter. When the electronic device is a PC, since the PC includes the charging circuit provided in the above embodiment, the charging circuit can realize closed-loop fast charging, and because the charging circuit includes the SC circuit, the charging efficiency can be improved, and the efficient and fast closed-loop charging can be realized. control.

The charging circuit introduced in the above embodiment is applied to the fast charging scenario of PC. The following describes the fast charging scenario applied to smart terminals and wearable devices. The smart terminal is a mobile terminal. For example, the smart terminal can be a mobile phone, a tablet computer, etc. The wearable device may be a Bluetooth headset, a watch, a VR, etc., and the specific types of the smart terminal and the wearable device are not specifically limited in the embodiments of the present application.

The second embodiment of the charging circuit:

Referring to FIG. 14 , this figure is a schematic diagram of another charging circuit provided by an embodiment of the present application. The charging circuit provided in this embodiment includes: a first switch transistor Q1, a second switch transistor Q2, a third switch transistor Q3, a fourth switch transistor Q4, a first capacitor Cfly and a first inductor L1; the first switch transistor The first end of Q1 is used to connect to the power supply end, the second end of the first switch tube Q1 is connected to the first end of the second switch tube Q2, and the second end of the second switch tube Q2 is connected to the first end of the second switch tube Q2. The first end of the three switch tube Q3, the second end of the third switch tube Q3 is connected to the first end of the fourth switch tube Q4, and the second end of the fourth switch tube Q4 is grounded; the first capacitor Cfly The two ends of the first switch tube Q1 are respectively connected to the second end of the first switch tube Q1 and the second end of the third switch tube Q3; the second end of the second switch tube Q2 is used as the first output terminal Vout2 for the first The battery of the electronic device is charged; the charging circuit is located inside the first electronic device. The second end of the first switch Q1 is connected to the first end of the first inductor L1, or the second end of the third switch Q3 is connected to the first end of the first inductor L1, and the first The second end of the inductor L1 is used as the second output end, that is, the load power supply end of the first electronic device.

It should be noted that the charging circuit includes two output terminals, which can be Vout1 and Vout2, or Vout2 and Vout3, and the two output terminals can supply power to two different loads at the same time. That is, the first output terminal is Vout2, and the second output terminal can be Vout1 or Vout3.

When the first electronic device is a mobile phone, the load of the first electronic device may be an electrical circuit inside the mobile phone. When the first electronic device is an earphone box, the load of the first electronic device can be the Bluetooth earphone in the earphone box, that is, the adapter can not only charge the battery of the earphone box, but also charge the battery of the earphone in the earphone box, that is, at this time As the second electronic device, the Bluetooth headset can simultaneously charge the headset box and the headset through the charging circuit adapter, that is, simultaneously charge the first electronic device and the second electronic device.

Referring to FIG. 15 , this figure is a schematic diagram of the first electronic device provided by the embodiment of the present application being an earphone box. The shell of the earphone box 401 is provided with a power supply terminal (not shown in the figure), that is, a charging interface. The earphone box 401 can be connected to the adapter 402 through the power supply terminal. After the adapter 402 is connected to the power supply, it can be the battery of the earphone box 401. Charge. At the same time, the earphone 403 inside the earphone box 401 can be charged.

Referring to FIG. 16 , which is a schematic diagram of the interior of the earphone box provided by the embodiment of the present application. Two independent earphones can be placed in the earphone box, namely the left earphone and the right earphone. When the earphone is put into the earphone box, the charging terminal 301 of the earphone box will be connected with the power receiving terminal 302 of the earphone, and then the charging of the earphone is completed. The earphone box, which is the first electronic device, is charged, and the earphone, which is the second electronic device, is charged at the same time.

The following description will be given by taking Vout1 and Vout2 as two output terminals of the charging circuit as an example. Referring to FIG. 17 , this figure is a schematic diagram of another charging circuit provided by an embodiment of the present application. The charging circuit provided in this embodiment can be applied not only to smart terminals such as mobile phones, but also to wearable devices such as Bluetooth headsets. In the charging circuit provided in this embodiment, when the second end of the first switch tube Q1 is connected to the first end of the first inductor L1, and the second end of the first inductor L1 is used as the second output end Vout1; Vout1 is directly connected to SYS , and also include: a reverse flow prevention switch tube RBFET, a fifth switch tube Q5 and a seventh switch tube Q7; the first end of the first switch tube Q1 is connected to the power supply terminal Vbus through the reverse flow prevention switch tube RBFET; The seventh switch tube Q7 is an optional device, and Q7 is connected in series between the second end of the first switch tube Q1 and the first end of the second switch tube Q2, and Q7 and Q2 form a back-to-back structure. It is guaranteed that the bidirectional turn-off function can be realized; it should be noted that in Figure 17, Q2 and Q7 are drawn as two independent switch tubes. In actual implementation, Q2 and Q7 can be a physical switch, and the physical switch can be composed of two tubes. The reverse series can also be realized by the substrate switching scheme, similar to Q5 in Figure 17, the purpose is to realize the function of bidirectional shutdown when it is turned off. The first end of the fifth switch transistor Q5 is connected to the second end of the first inductor L1, and the second end of the fifth switch transistor Q5 is connected to the first output end.

The charging circuit provided in this embodiment may include a controller (not shown in the figure), and the controller is used to control the seventh switch Q7 and the second switch Q2 to act synchronously, that is, to turn on or turn off at the same time; During the stage, the fifth switch Q5 is controlled to be disconnected; that is, during the open-loop charging stage, Q5 disconnects the connection between SYS and Vout2. During the constant voltage closed-loop charging stage, the fifth switch transistor Q5 is controlled to be turned on, that is, during the closed-loop charging stage, Vout1 and Vout2 are connected together through Q5.

The controller is further configured to control the first switch transistor Q1 and the third switch transistor Q3 to operate synchronously, and control the second switch transistor Q2 and the fourth switch transistor Q4 to operate synchronously during the open-loop charging stage , the actions of the first switch Q1 and the second switch Q2 are opposite; so that the first output terminal Vout2 charges the battery Vbat, and the second output terminal Vout1 supplies power to the load of the first electronic device, that is, to SYS. In order to facilitate the subsequent description, the concept of control strategy is introduced, in which control strategy 1 refers to: Q1 and Q3 act synchronously, Q2 and Q4 act synchronously, and Q1 and Q3 are inverted. ratio is D.

Refer to FIG. 18 , which is a path diagram of the open-loop charging phase corresponding to FIG. 17 . In the open-loop charging stage, for Vout1, that is, the power supply path of SYS is from Vbus-SYS, which is the same as the forward operation of path 1 in the first embodiment of the charging circuit, and will not be repeated here. The power supply path for Vout2 is from Vbus-Vout2, which is the same as that in the first embodiment of the charging circuit, that is, the forward operation of path 2; for the above open-loop charging stage, the charging path is also suitable for mobile phones and headphones and other application scenarios .

The working principle of the closed-loop charging stage is described in detail below with reference to the accompanying drawings. First, referring to Figure 19 and Figure 20, the case where the mobile phone and the earphone box are single-cell batteries, that is, the voltage of the adapter is greater than the battery voltage of the mobile phone, needs to be reduced to charge the battery of the mobile phone after the voltage of the adapter is lowered. In the closed-loop charging stage, Q5 is turned on, that is, SYS and Vout2 are connected together.

Referring to FIG. 19 and FIG. 20 , the figures are the path diagrams of step-down in the closed-loop charging stage corresponding to FIG. 17 . Among them, FIG. 19 is a schematic diagram showing that Q1 and Q3 are both turned on and Q4 is turned off. Figure 20 is a schematic diagram showing that Q1 and Q3 are both turned off and Q4 is turned on. During the closed-loop charging phase, Q2 and Q7 remain disconnected. The controller is further configured to control both the second switch tube Q2 and the optional seventh switch tube Q7 to turn off, control the fifth switch tube Q5 to turn on, and control the The first switch transistor Q1 and the third switch transistor Q3 operate synchronously, and the first switch transistor Q1 and the fourth switch transistor Q4 are controlled to operate in opposite directions. For the specific path, please refer to the direction of the current iL in the figure.

It can be seen from Figure 19 that when Q1 and Q3 are closed, Vbus supplies power to SYS through Q1 and L1, and simultaneously charges Vbat and Cfly. As can be seen from Figure 20, when Q1 and Q3 are turned off, Cfly supplies power to SYS and Vbat, that is, charges. At this time, the duty cycle of the driving signal of Q1 is D;

The gain of the charging circuit is:

Vsys is the voltage of SYS, that is, the output voltage range of Vsys is (0.5Vbus, Vbus). At this time, Vbat and Vsys are equal, and the proportional relationship between Vbat and Vbus is also the same as the above formula, which will not be repeated here. In order to facilitate the subsequent description, the control strategy is defined as control strategy 3: Q2 and Q7 are turned off, Q1 and Q3 are synchronized, and Q1 and Q4 are inverted.

First, referring to Figure 21 and Figure 22, the mobile phone and the earphone box are introduced with two batteries, that is, the voltage of the adapter is lower than the battery voltage of the mobile phone, and the voltage of the adapter needs to be boosted to charge the battery of the terminal equipment such as the mobile phone. Referring to FIG. 21 and FIG. 22 , the figures are the path diagrams of boosting in the closed-loop charging stage corresponding to FIG. 17 . Among them, Fig. 21 is a schematic diagram showing that Q1 and Q4 are both turned on and Q3 is turned off. Figure 22 is a schematic diagram showing that Q1 and Q4 are both turned off and Q3 is turned on. During the closed-loop charging phase, Q2 and Q7 remain disconnected. The controller is further configured to control both the second switch tube Q2 and the optional seventh switch tube Q7 to turn off, control the fifth switch tube Q5 to turn on, and control the The first switch transistor Q1 and the fourth switch transistor Q4 operate synchronously, and the first switch transistor Q1 and the third switch transistor Q3 are controlled to operate in opposite directions.

The gain of the charging circuit corresponding to Figure 21 and Figure 22 is:

That is, the output voltage range of Vsys is theoretically (Vbus, +∞), that is, the charging circuit realizes boost conversion. For the convenience of subsequent description, this control is defined as control strategy 4: Q2 and Q7 are turned off, Q1 and Q4 are synchronized, and Q1 and Q3 are inverted.

For the above charging scenarios of mobile phones and earphone boxes, the output voltage of the adapter is generally about 5V. When the load of the first electronic device is the second electronic device, the second output terminal is used to charge the second electronic device; for example, the first electronic device is an earphone box, and the second electronic device is an earphone, When the earphone is located in the earphone box, the earphone acts as the load of the earphone box.

The following describes that when the power supply end of the charging circuit is not connected to an adapter, that is, when there is no external power supply connected to the Vbus, the battery of the first electronic device can charge the second electronic device. That is, the controller is also used to control the charging circuit to boost the voltage of the battery to charge the second electronic device, to control the second switch Q2 to operate synchronously with the fourth switch Q4, and to control the second switch Q2 Contrary to the action of the third switch tube Q3, at this time, Q5 is closed and turned on, Q2 and Q7 act simultaneously, and Q2 and Q7 can be regarded as a switch tube, that is, tied together. That is to charge SYS after Vbat is boosted. In the case of the earphone box, the battery of the earphone box charges the earphone.

The charging circuit provided in this embodiment can be applied to mobile terminals and wearable devices, realizes high integration of fast charging, and realizes the effective integration of closed-loop transformer circuits and open-loop transformer circuits. High efficiency, and can use the voltage regulation function of the closed-loop transformer circuit, which can be applied to both single-cell batteries and dual-cell batteries, and has a wide range of application scenarios, which improves the universality of the charging circuit. Moreover, when the adapter is not connected, the first electronic device can also use the power of its own battery to charge the second electronic device. When the adapter is connected, the adapter can simultaneously charge the first electronic device and the second electronic device by using the charging circuit.

The charging circuit is implemented three:

Referring to FIG. 23 , this figure is a schematic diagram of another charging circuit provided by an embodiment of the present application. The two output terminals in this embodiment are the same as those in the second embodiment of the charging circuit, that is, the first output terminal of the two output terminals in this embodiment is Vout2, and the second output terminal is Vout1. The difference between this embodiment and the second embodiment of the charging circuit is that the connection relationship between the two output ends is different. As can be seen from FIG. 23, when the second end of the first switch tube Q1 is connected to the first end of the first inductor L1, and the second end of the first inductor L1 is used as the second output end Vout1, it also includes: The flow switch tube RBFET and the eighth switch tube Q8; the first end of the first switch tube Q1 is connected to the power supply terminal Vbus through the anti-backflow switch tube RBFET; the first end of the eighth switch tube Q8 is used to connect the power supply terminal Vbus, The second end of the eighth switch transistor Q8 is connected to the second output end Vout1. In this embodiment, Vout1 and Vout2, that is, Vout1 and Vbat are not directly connected together through a switch. It is prevented that only one of the reverse flow switch RBFET and the eighth switch Q8 is turned on at the same time, and will not be turned on at the same time.

The charging circuit provided by the embodiment of the present application further includes: a controller (not shown in the figure); the controller is configured to control the reverse flow prevention switch RBFET to be turned on during the open-loop charging stage, and control the eighth switch Q8 is turned off; in the constant voltage closed-loop charging stage, the eighth switch tube Q8 is controlled to be turned on, and the control prevents the reverse flow switch tube RBFET from being turned off.

For the mobile phone and headset scenarios, the paths are the same during the open-loop charging phase. That is, the controller is further configured to control the first switch transistor Q1 and the third switch transistor Q3 to operate synchronously, and control the second switch transistor Q2 and the fourth switch transistor during the open-loop charging stage Q4 operates synchronously, and the first switch Q1 and the second switch Q2 operate in opposite directions. The actions of Q1-Q4 are similar to those in the first embodiment of the charging circuit, and are not repeated here. It should be noted that the open-loop charging stage is an open-loop fast charging stage, and the closed-loop charging stage is a closed-loop fast charging stage.

During the closed-loop charging stage, the controller is further configured to control the second switch transistor Q2 and the fourth switch transistor Q4 to act synchronously, and control the second switch transistor Q2 and the third switch transistor Q3 to act in opposite directions . When the adapter is not connected, that is, when the Vbus is not connected to an external power supply, when the load of the electronic device is the second electronic device, the second output terminal is used to charge the battery of the second electronic device; the controller , is also used to control the second switch tube Q2 and the fourth switch tube Q4 to operate synchronously when the battery is used to charge the second electronic device, and to control the second switch tube Q2 and the fourth switch tube Q2 to operate synchronously. The action of the three-switch Q3 is opposite. That is, Vbat outputs power in the reverse direction to Vout1.

When the charging path is Vbat to reversely output power to Vout1, the gain is:

Vout2 is used as input, Vout1 is used as output, it is closed-loop boost conversion, and the output voltage range of Vout1 is (Vout2, 2*Vout2), which realizes boost conversion. On the contrary, when Vout1 is used as input and Vout2 is used as output, it is closed-loop step-down conversion, and the output voltage range of Vout2 is (0.5*Vout1, Vout1), which realizes step-down conversion. This embodiment is also applicable to the scenario where the adapter outputs a voltage of about 5V.

This solution can be applied to mobile terminals and wearable devices, realizes high integration of fast charging, and realizes the effective integration of closed-loop transformer circuit and open-loop transformer circuit. The voltage regulation function of the closed-loop transformer circuit can be applied to a wide range of single-cell battery application scenarios of various devices, that is, the universality of the charging circuit is improved. Moreover, when the adapter is not connected, the first electronic device can also use the power of its own battery to charge the second electronic device. When the adapter is connected, the adapter can simultaneously charge the first electronic device and the second electronic device by using the charging circuit. Compared with the second embodiment of the charging circuit, the charging circuit provided in this embodiment is simpler to implement and easy to implement in control. Especially when Vout1 is powered, it can supply power directly without power conversion, so the charging efficiency is higher.

The fourth embodiment of the charging circuit:

Referring to FIG. 24 , this figure is a schematic diagram of another charging circuit provided by an embodiment of the present application. The two output terminals in this embodiment are different from the second and third embodiments of the charging circuit. The first output terminal of the two output terminals in this embodiment is Vout2, the second output terminal is Vout3, and the charging circuit implements The two output terminals in Example 2 and Example 3 are Vout1 and Vout2 respectively. In addition, the charging circuit provided in this embodiment can realize the function of boosting, that is, it can be applied to the scenario where the battery is two batteries connected in series. To meet the charging requirements of the batteries, the charging circuit needs to boost the voltage of the 5V battery to charge the two batteries. The output voltage of the adapter is not specifically limited in this embodiment, and the above is only a specific schematic description. This embodiment is the same as the third embodiment of the charging circuit in that the two output ends are not connected together through a switch.

It can be seen from FIG. 24 that when the second end of the third switch tube Q3 is connected to the first end of the first inductor L1 and the second end of L1 is used as the second output end Vout3, it also includes: the anti-reverse flow switch tube RBFET and The ninth switch transistor Q9; when the second end of the third switch transistor Q3 is connected to the first end of the first inductor L1, the first end of the first switch transistor Q1 is used to connect through the backflow prevention switch transistor RBFET the power supply terminal; the second terminal of the first inductor L1 is connected to the power supply terminal through the ninth switch transistor Q9. Similarly, in this embodiment, only one of the reverse flow switch RBFET and the ninth switch Q9 is prevented from being turned on at the same time in the fast charging scenario, that is, the two will not be turned on at the same time.

The charging circuit provided in this embodiment may further include: a controller (not shown in the figure); the controller realizes the control of each working mode of the charging circuit. The controller is used to control the conduction of the reverse current switch tube RBFET in the open-loop charging stage, and control the ninth switch tube Q9 to be turned off; in the constant voltage closed-loop charging stage, control the ninth switch tube Q9 to be turned on, The anti-reverse flow switch RBFET is controlled to be turned off. That is to say, in the closed-loop charging stage, Vbus directly provides power to Vout3 through the closed Q9, without going through the conversion of the switch tube and the inductor, which can improve the power supply efficiency of Vout3 and reduce power loss, that is, improve the charging efficiency of Vout3.

The charging paths that can be implemented in Figure 24 are described below.

Path four:

Vbus to Vout3, the charging path belongs to the cascaded structure of SC circuit and Buck circuit, and the transmission gain is

That is, the forward direction from Vbus-Vout3 is a closed-loop buck mode, and the reverse direction from Vout3-Vbus is a closed-loop boost mode.

Path five:

Vout2-Vout3, the control strategy of this charging path is: Q1 and Q3 act synchronously, Q2 and Q4 act synchronously, Q1 and Q2 work in reverse phase, the duty cycle of Q1 conduction is D, then Vout2->Vout3 is Buck structure, From Vout3->Vout2 is the Boost structure. The controller is further configured to control the first switching transistor Q1 and the third switching transistor Q3 to operate synchronously, and control the second switching transistor Q2 and the fourth switching transistor Q4 to operate synchronously during the open-loop charging stage , the actions of the first switch transistor Q1 and the second switch transistor Q2 are opposite. The controller is further configured to control the first switch transistor Q1 and the third switch transistor Q3 to operate synchronously, and control the second switch transistor Q2 and the fourth switch transistor Q4 to synchronize during the closed-loop charging stage The actions of controlling the first switch transistor Q1 and the second switch transistor Q2 are opposite. It can be seen from the above analysis that, in the charging circuit provided in this embodiment, the control strategies of Q1-Q4 are exactly the same in the open-loop charging stage and the closed-loop charging stage, only the duty ratios are different.

The following is a separate analysis of the mobile phone as an example of the scene and the headset box as an example of the scene. In the open-loop charging stage of the mobile phone, the RBFET is turned on and Q9 is turned off, and the forward operation is performed in the same way as the path 2 described in the above embodiment. In the closed-loop charging stage of the mobile phone, or when the 5V adapter is connected, the RBFET is turned off and Q9 is turned on, that is, boost charging is performed according to the reverse Boost structure of path 5 above.

In the application scenario of the earphone box, the battery of the earphone box is connected to Vout2, and the earphone is connected to Vout3. In the open-loop charging stage, SC voltage regulation is supported, and the earphone box and earphone are charged at the same time, RBFET is turned on, and Q9 is turned off, that is, forward work is performed according to path 2 and path 4 at the same time, that is, the step-down charging mode. In the closed-loop charging stage, or when the 5V adapter is connected, configure Vbus to be 5V, RBFET is turned off, Q9 is turned on, Vbus=5V to directly charge the earphone, and the earphone box can be charged by referring to the reverse Boost working mode of path 5 above, that is, Boost charging mode.

When the adapter is not connected, that is, when the Vbus is not in place, the battery of the earphone box charges the earphone, and the forward Buck working mode is performed according to the path 5 introduced above, that is, the step-down charging mode. That is, when the load of the first electronic device is the second electronic device; the controller is further configured to use the battery to charge the second electronic device, and control the first switch tube Q1 and the third electronic device The switch Q3 operates synchronously, controls the second switch Q2 and the fourth switch Q4 to operate synchronously, and controls the first switch Q1 and the second switch Q2 to operate oppositely.

The charging circuit provided in this embodiment can work in both an open-loop charging mode and a closed-loop charging mode, and can work in both a buck charging mode and a boost charging mode. In addition, the second output terminal is connected to the power supply terminal through the controllable switch tube. When the controllable switch tube is turned on, the power supply terminal can directly supply power to the second output terminal without going through an intermediate power conversion link, thereby reducing power consumption and increasing the power consumption. charging efficiency. Since the charging circuit can work in the reverse boost mode, it can be applied to the scenario where multiple batteries are connected in series in mobile terminals such as mobile phones, for example, the charging scenario when two batteries are connected in series, so that it can be compatible with different adapters to meet different mobile needs. Charging requirements for terminals and wearable devices.

Embodiment 5 of the charging circuit:

Referring to FIG. 25A , this figure is a schematic diagram of still another charging circuit provided by an embodiment of the present application. The difference between this embodiment and the fourth embodiment of the charging circuit is that one switch tube is added, that is, a controllable switch tube. By changing the working state of the controllable switch tube, more working modes can be realized. The charging circuit provided in this embodiment is suitable for both a single-cell battery scenario and a dual-cell battery scenario, and is suitable for charging the battery of a mobile terminal, and is located inside the mobile terminal, for example, charging the battery of a mobile phone. The first output terminal of the charging circuit provided in this embodiment is Vout2, and the second output terminal is Vout3. That is, the charging circuit provided by this embodiment adds: a tenth switch Q10; the first end of the tenth switch Q10 is connected to the second end of the first inductor L1, and the second end of the tenth switch Q10 is connected to the second end of the first inductor L1. terminal to ground.

In the charging circuit provided by this embodiment, in the open-loop charging stage and the closed-loop boost charging stage, the controller is configured to control the first switch transistor Q1 and the third switch transistor Q3 to operate synchronously, and control the second switch The transistor Q2 and the fourth switch transistor Q4 operate synchronously, and the first switch transistor Q1 and the second switch transistor Q2 are controlled to operate in opposite directions.

It should be noted that the control of the ninth switch Q9 and the anti-reverse flow switch RBFET is specifically: a controller for controlling the anti-reverse switch RBFET to conduct during the open-loop charging stage, and controlling the first The ninth switch Q9 is turned off; in the closed-loop charging stage, the ninth switch Q9 is controlled to be turned on or periodically turned on, and the reverse-flow prevention switch RBFET is controlled to be turned off.

It should be noted that the closed-loop charging stage in this embodiment includes a closed-loop boost charging stage, a closed-loop step-down charging stage, and a closed-loop buck-boost charging stage. The controller's control strategy for Q9 is as follows: in the closed-loop boost charging stage, control Q9 to be turned on all the time; in the closed-loop step-down charging stage and the closed-loop buck-boost charging stage, control Q9 to be turned on periodically.

The control strategy of the closed-loop boost charging stage is:

The controller is further configured to control the ninth switch tube Q9 to be turned on all the time, control the tenth switch tube Q10 to be always off, and control the first switch tube Q1 and the third switch tube in the closed-loop boost charging stage Q3 operates synchronously, and controls the second switch transistor Q2 and the fourth switch transistor Q4 to operate synchronously.

The control strategy in the closed-loop step-down charging stage is: the controller is also used to control the ninth switch Q9 to be turned on periodically, and the controller is controlled to turn on the ninth switch Q9 and the tenth switch Q10 alternately , the fourth switch transistor Q4 is controlled to be turned off, and the third switch transistor Q3 is controlled to be turned on.

The control strategy of the closed-loop buck-boost charging stage is:

The controller is further configured to control the ninth switch transistor Q9 to be periodically turned on, and control the first switch transistor Q1, the third switch transistor Q3 and the tenth switch transistor Q10 to be synchronized in the closed-loop boost-boost charging stage operation, the second switch transistor Q2, the fourth switch transistor Q4 and the ninth switch transistor Q9 are controlled to operate synchronously.

Referring to FIG. 25B , this figure is another schematic diagram based on FIG. 25A provided by the embodiment of the present application. The difference between this embodiment and the fourth embodiment of the charging circuit is that two switch tubes are added, that is, two controllable switch tubes. By changing the working state of the controllable switch tubes, more working modes can be realized. Compared with FIG. 25A, FIG. 25B adds a controllable switch tube, that is, Q11.

The charging circuit provided in this embodiment is suitable for both a single-cell battery scenario and a dual-cell battery scenario, and is suitable for charging a wearable device, such as charging an earphone box. In addition, it can also be applied to the above scenarios of charging a mobile phone, wherein Q11 is not required in a mobile phone charging scenario, that is, Q11 can be removed, including Q10. When Q11 is included, Q11 can be controlled to be turned on all the time, that is, it does not participate in the role of electric energy conversion. The first output terminal of the charging circuit provided in this embodiment is Vout2, and the second output terminal is Vout3.

As shown in FIG. 25B , the two added switch transistors in this embodiment are the tenth switch transistor Q10 and the eleventh switch transistor Q11 respectively. Q10 and Q11 are required in the charging scene of the earphone box. And in the charging scene of the earphone box to the earphone, the function of BuckBoost can be realized. The charging circuit provided in this embodiment works in path 4 + control strategy 1, that is, from Vbus to Vout3, RBFET is turned on and Q9 is turned off; in control strategy 1, Q10 operates synchronously with Q1 and Q3, and Q11 operates synchronously with Q2 and Q4 , the gain is:

Both forward closed-loop buck mode and closed-loop boost mode can be implemented. For details, please refer to FIG. 26 , which is a schematic diagram of a working mode corresponding to FIG. 25B . Figure 26 corresponds to the path diagram in which the controller controls Q1 and Q3 to be turned on and Q2 and Q4 to be turned off, wherein Q10 and Q3 act synchronously, and Q11 and Q4 act synchronously.

Referring to FIG. 27 , this figure is a schematic diagram of another working mode corresponding to FIG. 25B . Figure 27 corresponds to the path diagram in which the controller controls Q1 and Q3 to be turned off and Q2 and Q4 to be turned on, wherein Q10 and Q3 act synchronously, and Q11 and Q4 act synchronously.

The charging circuit provided in this embodiment can also work in path 5 + control strategy 1:

Vout2-Vout3, the path is the same as the above control strategy; the topology is a variant BuckBoost structure, and the gain is:

Both forward closed-loop buck mode and closed-loop boost mode can be implemented. For example, when the application scenario is an earphone box, when the earphone box is charging the earphone, Vout2 outputs power to Vout3, as shown in Figure 28, which is the path diagram corresponding to Figure 25 when Vbus is not connected to the power supply. At this point, the Vbus is not connected to external power, that is, the adapter is not connected to the headphone box. The control strategy corresponding to Figure 28 is basically the same as Figure 26, except that the RBFET switch in this figure should be kept off, and other control strategies are the same, that is, the controller controls Q1 and Q3 to be turned on, Q2 and Q4 are turned off, and Q10 and Q3 are synchronized When Q1 and Q3 are both turned off, the path when both Q2 and Q4 are turned on is basically the same as that in Figure 27, the difference is also that the RBFET switch should be kept off.

In addition, the above control strategy can be further simplified to improve the power conversion efficiency. For example, when the output voltage of Vout3 is lower than Vout2, the charging circuit provided in this embodiment can work in a variant Buck mode. At this time, on the basis of control strategy 1, Q10 is controlled to be always off, and Q11 is always turned on; the gain is:

At this time, the charging circuit can realize the forward closed-loop step-down mode. The modal diagram when the controller controls Q1 and Q3 to turn on is shown in Figure 29, and the modal diagram when the controller controls Q1 and Q3 to turn off is shown in Figure 30. As can be seen from Figure 29 and Figure 30, Q10 is always off and Q11 is always on.

In addition, when the output voltage of Vout3 is higher than Vout2, the charging circuit provided in this embodiment can work in the traditional Boost mode. At this time, Q1, Q2 and Q4 are controlled to be always off, Q3 is always turned on, and Q10 and Q11 are controlled to be turned on alternately. . The duty cycle of Q10 is D, then the gain is:

At this time, the charging circuit can realize a closed-loop boosting working mode. The corresponding working mode diagrams are shown in FIG. 31 and FIG. 32 , wherein in FIG. 31 , Q11 is turned off and Q10 is turned on. Figure 32 is a schematic diagram showing that Q11 is turned on and Q10 is turned off, and the current path in it can refer to the direction of current iL. At most one RBFET and Q9 can be turned on at the same time; in the fast charging scenario of mobile phones, Q11 is not required. If there is Q11, it can be controlled to be turned on all the time.

When the fast charging of the mobile phone is in the open-loop fast charging state, that is, the open-loop charging stage, the RBFET is turned on, Q9 is turned off, and the same path 2 works forward. When the mobile phone fast charging works in the closed-loop charging stage, or when the 5V adapter is plugged in for charging, the RBFET is turned off and Q9 replaces the function of Q11, which is the same as the working mode of path 5 + control strategy 1 in the above figure, that is, the reverse BuckBoost working mode. In addition, the simplified control strategy for improving the power conversion efficiency is also applicable to the closed-loop charging stage of the mobile phone, which will not be repeated here.

In the fast charging scenario of the earphone box, Q11 is required at this time. Headphones can be connected to Vout3, and the battery of the headphone box is connected to Vout2. The open-loop charging stage of the Vbus connection adapter, that is, the open-loop fast charging stage, supports SC voltage regulation, and performs fast charging for headphones and headphone boxes at the same time; RBFET is turned on and Q9 is turned off, which is the same as the above-mentioned path 2 and path 4+ control Strategy 1 works in the forward direction at the same time; Vbus=5V is inserted or the earphone box is charged and enters the closed-loop charging stage (configured with Vbus=5V), RBFET is turned off, Q9 is turned on, Vbus=5V directly charges the earphone, and the earphone box is charged according to the above introduction Path 5 + control strategy 1, at this time, the charging circuit works in the reverse BuckBoost working mode; in addition, the corresponding simplified control strategy for improving the power conversion efficiency is also applicable, and will not be repeated here.

When the Vbus is not connected to an external power source, that is, when the adapter is not in place, the battery of the earphone box charges the earphone. According to the path 5 + control strategy 1 introduced above, the charging circuit works in the forward BuckBoost working mode. In addition, when the earphone box charges the earphone, the corresponding simplified control strategy for improving the power conversion efficiency is also applicable, which will not be repeated here.

The charging circuit provided in this embodiment has the advantages of the second embodiment of the charging circuit to the fourth embodiment of the charging circuit, and can work in the open-loop charging mode, the closed-loop charging mode, and the step-down charging mode. , and can work in boost charging mode. In addition, the second output terminal is connected to the power supply terminal through the controllable switch tube. When the controllable switch tube is turned on, the power supply terminal can directly supply power to the second output terminal without going through an intermediate power conversion link, thereby reducing power consumption and increasing the power consumption. charging efficiency. Since the charging circuit can work in the reverse boost mode, it can be applied to the multi-battery series connection scenario of mobile terminals such as mobile phones, such as the charging scenario when two batteries are connected in series, so that it can be compatible with different adapters to meet the needs of different mobile terminals. and the charging needs of wearable devices. In addition, the charging circuit provided in this embodiment also has the following advantages, that is, the charging circuit can work in the boost mode and the step-down mode. The voltage of the battery is boosted to charge the earphones, and the voltage of its own battery can be reduced to charge the earphones. It can be flexibly controlled to charge the earphones when the batteries of the earphone box have different power levels.

The above embodiments of the charging circuit from the second embodiment to the fifth embodiment of the charging circuit are all applicable to the charging of mobile terminals and wearable devices. The charging circuit provided by the embodiment of the present application is not the open-loop charging circuit that includes two parallel circuits as shown in FIG. The closed-loop charging circuit integrates the open-loop charging circuit and the closed-loop charging circuit organically. The controller can realize different charging paths by controlling the different working modes of the switch tube. When open-loop charging is required, the open-loop charging can be used. Fast charging with high efficiency. When closed-loop charging is required, stable fast charging can be achieved by using the working stability of the closed-loop. Moreover, some of the above charging circuits are also suitable for boost charging, so that they can be compatible with scenarios where the input voltage of the adapter is low, or compatible with scenarios where the electronic device to be charged includes two series-connected batteries. Therefore, the charging circuit provided by the above embodiments of the present application improves the integration of various charging circuits, reduces the circuit size, and can meet different application scenarios, thereby improving the universality of the charging circuit.

The type of each switch in the charging circuit provided by the above embodiments of the present application is not specifically limited. For example, it can be implemented by a MOS transistor, or by a triode or a transistor. For example, Q1-Q4 can be NMOS transistors.

Based on the second embodiment of the charging circuit to the fifth embodiment of the charging circuit, the embodiment of the present application further provides an electronic device, which will be described in detail below with reference to the accompanying drawings.

Second embodiment of electronic equipment:

An embodiment of the present application further provides an electronic device, including: a battery and the charging circuit provided by any one of the foregoing charging circuit embodiment 2 to charging circuit embodiment 5. Referring to FIG. 33 , this figure is a schematic diagram of another electronic device provided by an embodiment of the present application. The first end of the charging circuit 100A is used to connect to the power supply end Vbus, and the first output end Vout2 of the charging circuit 100A is used to connect to the battery, that is, Vbat is not shown in the figure; the second output end of the charging circuit 100A Vout1 or Vout3 is used to connect the load of the first electronic device. It should be noted that the load of the first electronic device may be a power circuit or a second electronic device; for example, for the application scenario of a mobile phone, the first electronic device For the mobile phone, the battery of the first electronic device is the battery of the mobile phone, and the load of the first electronic device may be the power consumption circuit inside the mobile phone. For an application scenario of an earphone box, the first electronic device is an earphone box, and the load of the first electronic device is an earphone.

The charging circuit 100A is used for converting the electric energy provided by the power supply terminal Vbus to charge the battery and supply power to the load of the electronic device. That is, in FIG. 33 , the battery of the first electronic device is 200A, and the load of the first electronic device is 300A. The load of the first electronic device is another battery with a smaller capacity as an example. For example, for the application scenario of the earphone box, The load of the headphone box is the headphone battery, which is 300A.

In the electronic device provided by the embodiments of the present application, since the charging circuit includes two output terminals, two charging paths can be implemented, respectively, to perform fast charging for two different charged batteries or charged loads. Because the charging circuit included in the electronic device can work in both an open-loop charging mode and a closed-loop charging mode, and can work in both a step-down charging mode and a boost charging mode. In addition, the second output terminal is connected to the power supply terminal through the controllable switch tube. When the controllable switch tube is turned on, the power supply terminal can directly supply power to the second output terminal without going through an intermediate power conversion link, thereby reducing power consumption and increasing the power consumption. charging efficiency. Since the charging circuit can work in the reverse boost mode, it can be applied to scenarios where the battery capacity of mobile terminals such as mobile phones is relatively large, such as the charging scenario when two batteries are connected in series, so that it can be compatible with different adapters to meet different requirements. Charging requirements for mobile terminals and wearable devices.

It should be understood that, in this application, "at least one (item)" refers to one or more, and "a plurality" refers to two or more. "And/or" is used to describe the relationship between related objects, indicating that there can be three kinds of relationships, for example, "A and/or B" can mean: only A, only B, and both A and B exist , where A and B can be singular or plural. The character "/" generally indicates that the associated objects are an "or" relationship. "At least one item(s) below" or similar expressions thereof refer to any combination of these items, including any combination of single item(s) or plural items(s). For example, at least one (a) of a, b or c, can mean: a, b, c, "a and b", "a and c", "b and c", or "a and b and c" ", where a, b, c can be single or multiple.

As mentioned above, the above embodiments are only used to illustrate the technical solutions of the present application, but not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand: The technical solutions described in the embodiments are modified, or some technical features thereof are equivalently replaced; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions in the embodiments of the present application.

Claims (30)

A charging circuit, comprising: a first switch tube, a second switch tube, a third switch tube, a fourth switch tube, a first capacitor, a second capacitor and a first inductor; The first end of the first switch tube is used to connect to the power supply terminal, the second end of the first switch tube is connected to the first end of the second switch tube, and the second end of the second switch tube is connected to the the first end of the third switch tube, the second end of the third switch tube is connected to the first end of the fourth switch tube, and the second end of the fourth switch tube is grounded; Two ends of the first capacitor are respectively connected to the second end of the first switch tube and the second end of the third switch tube; The second end of the second switch tube is grounded through the second capacitor; The second end of the first switch tube is connected to the first end of the first inductor, and the second end of the first inductor serves as a charging output end for charging the battery of the electronic device. The charging circuit according to claim 1, further comprising: a reverse-flow prevention switch tube and a fifth switch tube; The first end of the first switch tube is connected to the power supply terminal through the reverse-flow prevention switch tube; the second end of the first inductor is connected to the system power supply terminal of the electronic device through the fifth switch tube. The charging circuit according to claim 1 or 2, wherein the first end of the first switch tube is connected to a system power supply end of the electronic device; The controller is further configured to control the first switch tube and the third switch tube to operate synchronously, and control the second switch tube and the fourth switch tube when the battery is charged by the power supply terminal. The switches operate synchronously, and the actions of the first switch and the second switch are opposite. The charging circuit according to claim 1, further comprising: a reverse-flow prevention switch and a charge-discharge control switch; The first end of the first switch tube is connected to the power supply terminal through the anti-reverse flow switch tube; The second end of the first inductor is connected to the battery through the charge-discharge control switch; The second end of the first inductor is connected to the system power supply end of the electronic device. The charging circuit according to claim 1 or 4, wherein the controller is further configured to control the first switch tube and the first switch when the battery is charged by reducing the voltage of the power supply terminal. The three switches operate synchronously to control the second switch and the fourth switch to operate synchronously, and the first switch and the second switch operate oppositely. The charging circuit according to claim 4 or 5, further comprising: a sixth switch; The first end of the sixth switch tube is connected to the second end of the third switch tube, and the second end of the sixth switch tube is connected to the second end of the first inductor; The controller is further configured to control both the second switch tube and the third switch tube to be disconnected, and control the first switch tube and all The fourth switch tube operates synchronously, and controls the first switch tube and the sixth switch tube to operate oppositely. An electronic device, comprising: a battery and the charging circuit according to any one of claims 1-6; The first end of the charging circuit is used to connect to the power end, and the second end of the charging circuit is connected to the power end of the battery; The charging circuit is used for charging the battery after converting the electric energy provided by the power supply terminal. A charging circuit, comprising: a first switch tube, a second switch tube, a third switch tube, a fourth switch tube, a first capacitor and a first inductor; The first end of the first switch tube is used to connect to the power supply terminal, the second end of the first switch tube is connected to the first end of the second switch tube, and the second end of the second switch tube is connected to the the first end of the third switch tube, the second end of the third switch tube is connected to the first end of the fourth switch tube, and the second end of the fourth switch tube is grounded; Two ends of the first capacitor are respectively connected to the second end of the first switch tube and the second end of the third switch tube; The second end of the second switch tube is used as the first output end for charging the battery of the first electronic device; The second end of the first switch tube is connected to the first end of the first inductor, or the second end of the third switch tube is connected to the first end of the first inductor, and the first end of the first inductor is The second terminal serves as a second output terminal to supply power to the load of the first electronic device. The charging circuit according to claim 8, further comprising: a controller; The controller is further configured to control the first switch tube and the third switch tube to operate synchronously, and control the second switch when the power supply terminal is used to perform the open-loop charging phase for the battery The tube and the fourth switch tube act synchronously, and the actions of the first switch tube and the second switch tube are opposite. The charging circuit according to claim 8 or 9, further comprising: a controller and a fifth switch tube; the first end of the fifth switch tube is connected to the second end of the first inductor, and the The second end of the fifth switch tube is connected to the first output end; The controller is further configured to control the second switch tube to open, control the fifth switch tube to close, and control the first switch tube and the third switch tube to act synchronously during the closed-loop charging stage, The actions of controlling the first switch tube and the fourth switch tube are opposite. The charging circuit according to claim 8 or 9, further comprising: a controller and a fifth switch tube; the first end of the fifth switch tube is connected to the second end of the first inductor, and the The second end of the fifth switch tube is connected to the first output end; The controller is further configured to control the second switch tube to be disconnected, control the fifth switch tube to be closed, and control the first switch tube and the fourth switch tube to synchronize during the closed-loop charging stage Action, the actions of controlling the first switch tube and the third switch tube are opposite. The charging circuit according to claim 10 or 11, wherein when the load of the first electronic device is the second electronic device, the second output terminal is used to charge the second electronic device; The controller is further configured to control the second switch to operate synchronously with the fourth switch to control the second switch when charging the second electronic device after the voltage of the battery is boosted The action of the tube is opposite to that of the third switch tube. The charging circuit according to claim 8, wherein the second end of the first switch is connected to the first end of the first inductor, further comprising: a reverse flow prevention switch and an eighth switch; The first end of the first switch tube is connected to the power supply terminal through the anti-reverse flow switch tube; The first end of the eighth switch tube is used to connect to the power supply end, and the second end of the eighth switch tube is connected to the second output end. The charging circuit of claim 13, further comprising: a controller; The controller is used to control the conduction of the anti-reverse flow switch in the open-loop charging stage, and control the eighth switch to be turned off; in the closed-loop charging stage, control the eighth switch to be turned on, and control the The backflow prevention switch tube is disconnected. The charging circuit according to claim 14, wherein the controller is further configured to control the first switch transistor and the third switch transistor to operate synchronously during the open-loop charging stage, and control all The second switch tube and the fourth switch tube act synchronously, and the first switch tube and the second switch tube act in opposite directions. The charging circuit according to claim 14 or 15, wherein the controller is further configured to control the second switch tube and the fourth switch tube to operate synchronously during the closed-loop charging stage, and control the The actions of the second switch tube and the third switch tube are opposite. The charging circuit according to any one of claims 14-16, wherein when the load of the first electronic device is a second electronic device, the second output terminal is used for the second electronic device battery charge; The controller is further configured to control the second switch tube and the fourth switch tube to act synchronously when the battery is used to charge the second electronic device, and to control the second switch tube and the fourth switch tube to act synchronously. The action of the third switch tube is opposite. The charging circuit according to claim 8, wherein the second end of the third switch is connected to the first end of the first inductor, further comprising: a reverse-flow prevention switch and a ninth switch; The first end of the first switch tube is used for connecting to the power supply terminal through the anti-reverse flow switch tube; The second end of the first inductor is connected to the power end through the ninth switch. The charging circuit of claim 18, further comprising: a controller; The controller is configured to control the conduction of the reverse-flow prevention switch tube and control the ninth switch tube to be turned off in the open-loop charging stage; and control the ninth switch tube to be turned on or cycled in the closed-loop charging stage Sexual conduction, control the anti-reverse flow switch tube to disconnect. The charging circuit according to claim 19, wherein the controller is further configured to control the first switch tube and the third switch tube to operate synchronously during the open-loop charging stage, and control all The second switch tube and the fourth switch tube act synchronously, and the first switch tube and the second switch tube act in opposite directions. The charging circuit according to claim 19 or 20, wherein the controller is further configured to control the first switch tube and the third switch tube to operate synchronously during the closed-loop charging stage, and control the The second switch tube and the fourth switch tube act synchronously, and the actions of the first switch tube and the second switch tube are controlled to be opposite. The charging circuit according to any one of claims 19-21, wherein when the load of the first electronic device is a second electronic device; The controller is further configured to use the battery to charge the second electronic device, control the first switch tube and the third switch tube to act synchronously, and control the second switch tube and the third switch tube to operate synchronously. The synchronous action of the four switch tubes controls the actions of the first switch tube and the second switch tube to be opposite. The charging circuit according to claim 19, further comprising: a tenth switch; The first end of the tenth switch tube is connected to the second end of the first inductor, and the second end of the tenth switch tube is grounded. The charging circuit according to claim 23, wherein the controller is further configured to control the ninth switch tube to be periodically turned on during the closed-loop step-down charging stage, and control the ninth switch tube of the controller It is alternately turned on with the tenth switch tube, the fourth switch tube is controlled to be turned off, and the third switch tube is controlled to be turned on. The charging circuit according to claim 23 or 24, wherein the controller is further configured to control the ninth switch transistor to be periodically turned on, and control the first switch transistor in a closed-loop buck-boost charging stage , the third switch tube and the tenth switch tube act synchronously, and control the second switch tube, the fourth switch tube and the ninth switch tube to act synchronously. The charging circuit according to any one of claims 23-25, further comprising: an eleventh switch; The first end of the eleventh switch tube is connected to the second end of the first inductor, and the second end of the eleventh switch tube is used as the second output end; the controller is also used to control The eleventh switch tube and the fourth switch tube act synchronously. The charging circuit according to claim 26, wherein the controller is further configured to control the first switch transistor and the third switch transistor to operate synchronously, and control the second switch transistor and the first switch transistor to operate synchronously. The four switches operate synchronously, the first switch and the second switch operate oppositely, the tenth switch and the third switch are controlled to operate synchronously, and the eleventh switch is controlled to be connected to the third switch. The fourth switch tube acts synchronously. The charging circuit according to claim 26, wherein the controller is further configured to control the tenth switch to turn off when the voltage of the second output terminal is lower than the voltage of the first output terminal, Control the eleventh switch tube to be turned on; control the first switch tube and the third switch tube to operate synchronously, control the second switch tube and the fourth switch tube to operate synchronously, and control the first switch tube The actions of the switch tube and the second switch tube are opposite. The charging circuit according to claim 26, wherein the controller is further configured to control the first switch, the first switch when the voltage of the second output terminal is greater than the voltage of the first output terminal Both the second switch tube and the fourth switch tube are turned off, the third switch tube is controlled to be turned on, and the tenth switch tube and the eleventh switch tube are controlled to be turned on alternately. An electronic device, comprising: a battery and the charging circuit according to any one of claims 8-29; The first end of the charging circuit is used to connect to the power supply end, the first output end of the charging circuit is used to connect to the battery; the second output end of the charging circuit is used to connect the load of the electronic device; The charging circuit is used for converting the electric energy provided by the power supply terminal to charge the battery and supply power to the load of the electronic device.

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