Charging circuit and electronic equipment

Abstract

The present application discloses a charging circuit and electronic device. The charging circuit includes four switching tubes connected in series: a first switching tube, a second switching tube, a third switching tube, and a fourth switching tube, as well as a first capacitor, a second capacitor, and a first inductor. The first end of the first switching tube is connected to a power supply terminal, and the two ends of the first capacitor are connected to the second end of the first switching tube and the second end of the third switching tube. The second end of the second switching tube is grounded via a second capacitor. The second end of the first switching tube is connected to the first end of the first inductor, and the second end of the first inductor serves as a charging output terminal to charge the battery of the electronic device. The charging circuit improves the integration level, which can reduce the area and volume occupied by the circuit and improve charging efficiency. When the electronic device is a PC, the 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 boosting and bucking is achieved, thereby improving universality and compatibility with different adapters.

Description

Technical Field

[0001] The present application relates to the field of electronic technology, and in particular to a charging circuit and electronic equipment. Background Art

[0002] Currently, more and more electronic devices require fast charging, i.e., fast charging, especially for mobile terminals such as mobile phones. As the frequency of use increases, fast charging has become a standard feature of mobile phones. The current charging process of electronic devices includes a constant current (CC) charging stage and a constant voltage (CV) charging stage. Most of the fast charging circuits inside mobile phones use a switched capacitor (SC) circuit. Since the SC circuit is an open-loop regulation, the charging efficiency is relatively high. Because the SC circuit does not have closed-loop regulation capabilities, the adapter needs to adjust its own output voltage to obtain a suitable charging current to provide to the SC circuit. The SC circuit currently only works in the CC charging stage, and a closed-loop voltage regulation circuit is also required in the CV charging stage.

[0003] The following is an introduction using a mobile phone as an example. Figure 1 , this figure is a schematic diagram of a fast charging system located inside a mobile phone provided by 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 regulation circuit 20. The closed-loop voltage regulation circuit 20 includes Buck or Boost. When the battery of the mobile phone is single-cell, Buck is used to charge the battery. When the battery of the mobile phone is dual-cell, Boost is selected to charge the battery. When the adapter is not online, that is, when Vbus has no input power, Vbat directly powers the system SYS inside the mobile phone through the closed switch tube BATFET.

[0004] from Figure 1 It can be seen that the current fast charging circuit of mobile phones and other electronic devices includes two independent parallel circuits, and different charging circuits are used to charge the battery in the CC and CV stages. The architecture is relatively complex and difficult to achieve high integration.

[0005] Application Contents

[0006] The present application provides a charging circuit and an electronic device, which can achieve high integration of fast charging circuits, have a simple structure and are easy to implement.

[0007] An embodiment of the present application provides a charging circuit, comprising the following four switching tubes connected in series: a first switching tube, a second switching tube, a third switching tube, and a fourth switching tube, and also comprising: a first capacitor, a second capacitor, and a first inductor; the first end of the first switching tube is used to connect to a power supply end, and the two ends of the first capacitor are respectively connected to the second end of the first switching tube and the second end of the third switching tube; the second end of the second switching tube is grounded via the second capacitor; the second end of the first switching 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 a battery of an electronic device.

[0008] The charging circuit provided in the embodiments of the present application combines the high efficiency advantages of the SC circuit with the voltage stabilization provided by the closed-loop control of the Buck circuit. It integrates the functions of the open-loop and closed-loop voltage transformer circuits into one, achieving a highly integrated charging circuit with a simple structure and ease of implementation. Therefore, this charging circuit can improve charging efficiency, thereby enabling fast charging in PC scenarios.

[0009] Preferably, in order to prevent the current from the system power supply end from flowing to the power supply end, the charging circuit also includes: an anti-backflow switch tube, that is, the first end of the first switch tube is connected to the power supply end through the anti-backflow switch tube; in addition, a fifth switch tube is also provided; the second end of the first inductor is connected to the system power supply end of the electronic device through the fifth switch tube.

[0010] Preferably, for a hybrid power supply boost charging scenario, the charging circuit can implement a buck charging mode, wherein the first end of the first switch tube is connected to the system power supply end of the electronic device; the controller is further used to control the first switch tube and the third switch tube to operate synchronously, and to control the second switch tube and the fourth switch tube to operate synchronously, when the battery is charged using the power supply end, and the first switch tube and the second switch tube operate in opposite directions.

[0011] Preferably, for narrow-voltage DC charging scenarios, the charging circuit also includes: a reverse current prevention switch and a charge-discharge control switch. Similarly, the reverse current prevention switch prevents other current from flowing back to the power supply, thereby achieving a shutdown function. The first end of the first switch is connected to the power supply through the reverse current prevention switch; the second end of the first inductor is connected to the battery through the charge-discharge control switch; and the second end of the first inductor is connected to the system power supply of the electronic device.

[0012] Preferably, the charging circuit can implement a Buck step-down charging mode under the control of a controller, that is, when the controller uses the power supply end to step down the voltage to charge the battery, it controls the first switch tube and the third switch tube to operate synchronously, and controls the second switch tube and the fourth switch tube to operate synchronously, and the actions of the first switch tube and the second switch tube are opposite.

[0013] Preferably, the charging circuit provided in the embodiments of the present application can also implement boost charging, i.e., Boost operating mode, and further includes: a sixth switch tube; 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 the second and third switches to be disconnected, the first and fourth switches to operate synchronously, and the first and sixth switches to operate in opposite directions when charging the battery after the power supply terminal boosts the voltage. This charging circuit is suitable for scenarios where two batteries are connected in series and boosting is required to charge the series-connected batteries.

[0014] Based on the charging circuit provided in the above embodiment, another embodiment of the present application provides an electronic device comprising: a battery and the charging circuit described above; a first end of the charging circuit is connected to a power supply terminal, and a second end of the charging circuit is connected to the power supply terminal of the battery; the charging circuit is configured to convert electrical energy provided by the power supply terminal to charge the battery. For example, the electronic device may be a PC.

[0015] An embodiment of the present application also provides a charging mode control method, including: obtaining a priority charging mode, if it is a performance priority charging mode, configuring the adapter voltage to be a maximum value; if it is a fast charging priority mode, dynamically adjusting the adapter voltage according to the battery voltage.

[0016] Therefore, the charging control method provided in the embodiment of the present application can achieve maximum balance between system performance and charging performance, and the controller can select the control strategy as needed.

[0017] In addition, this embodiment of the present application also provides another charging mode control method, including: detecting the adapter type and the maximum output voltage of the Vbus terminal. When the maximum adapter voltage is greater than the battery voltage, the charging circuit is configured to operate in a buck charging mode; when the maximum adapter voltage is less than the battery voltage, the charging circuit is configured to operate in a boost charging mode.

[0018] In addition, an embodiment of the present application further provides a computer-readable storage medium, including instructions or a computer program, which, when executed on a computer, enables the computer to execute the charging control method described above.

[0019] Through the description of the above embodiments, it can be known that those skilled in the art can clearly understand that all or part of the steps in the above embodiment methods 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, which can be stored in a storage medium, such as a read-only memory (ROM) / RAM, a magnetic disk, an optical disk, etc., and includes a number of program codes or instructions for enabling a computer device (which can be a personal computer, a server, or a network communication device such as a router) to execute the methods described in each embodiment or certain parts of the embodiments of the present application.

[0020] An embodiment of the present application also provides a charging circuit, comprising: a first switching tube, a second switching tube, a third switching tube, a fourth switching tube, a first capacitor, and a first inductor; the first end of the first switching tube is used to connect to a power supply end, the second end of the first switching tube is connected to the first end of the second switching tube, the second end of the second switching tube is connected to the first end of the third switching tube, the second end of the third switching tube is connected to the first end of the fourth switching tube, and the second end of the fourth switching tube is grounded; the two ends of the first capacitor are respectively connected to the second end of the first switching tube and the second end of the third switching tube; the second end of the second switching tube serves as a first output end, used to charge a battery of a first electronic device; the second end of the first switching tube is connected to the first end of the first inductor, or the second end of the third switching tube is connected to the first end of the first inductor, and the second end of the first inductor serves as a second output end to power a load of the first electronic device.

[0021] When the charging circuit has two output terminals, it can be applied to scenarios such as terminal devices 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; for example, the first electronic device is an earphone box, and the second electronic device is an earphone. When the earphone is in the earphone box, the earphone serves as the load of the earphone box. In the scenario corresponding to 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, realizes the effective integration of closed-loop transformer circuits and open-loop transformer circuits, can utilize both the high efficiency of open-loop transformer circuits and the voltage stabilization function of closed-loop transformer circuits, can be applied to both single-cell batteries and double-cell batteries, and has a wide range of application scenarios, which improves the universality of the charging circuit. In addition, 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.

[0022] Preferably, the charging circuit can implement open-loop charging, i.e., open-loop fast charging, which can improve charging efficiency while fast charging. This open-loop fast charging is suitable for mobile phone scenarios and headphone box scenarios. The controller, when using the power supply end to perform the open-loop charging phase for the battery, controls the first and third switching tubes to operate synchronously, and controls the second and fourth switching tubes to operate synchronously, with the first and second switching tubes operating in opposite directions.

[0023] Preferably, the charging circuit further 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 output end; the controller is further configured to control the second switch to be disconnected, the fifth switch to be closed, the first and third switches to operate synchronously, and the first and fourth switches to operate in opposite directions during the closed-loop charging phase. This charging mode is a closed-loop buck charging mode.

[0024] Preferably, the device further 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 output end; the controller is further configured to control the second switch to be disconnected, the fifth switch to be closed, the first switch and the fourth switch to operate synchronously, and the first switch and the third switch to operate in opposite directions during the closed-loop charging phase. This charging mode is a closed-loop boost charging mode.

[0025] Preferably, 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. The controller is further configured to control the second switch to operate synchronously with the fourth switch, and to control the second switch to operate in the opposite direction to the third switch, when charging the second electronic device after the battery voltage is boosted. For example, in an application scenario involving a headphone box, the first electronic device is the headphone box, and the second electronic device is headphones, with the headphone box using its own battery voltage to charge the headphones.

[0026] Preferably, the Buck+ switched capacitor SC charging mode is introduced below. When the second end of the first switch tube is connected to the first end of the first inductor, it also includes: an anti-backflow switch tube and an eighth switch tube; the first end of the first switch tube is connected to the power supply end through the anti-backflow 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.

[0027] Preferably, it also includes: a controller; the controller is used to control the anti-backflow switch tube to be turned on and the eighth switch tube to be turned off in the open-loop charging stage; in the closed-loop charging stage, the eighth switch tube is controlled to be turned on and the anti-backflow switch tube is controlled to be turned off.

[0028] Preferably, the following describes an open-loop charging scenario applicable to both mobile phones and headphones, specifically a single-battery charging scenario. The controller is further configured to control the synchronous operation of the first and third switching transistors, and the synchronous operation of the second and fourth switching transistors, during the open-loop charging phase. The first and second switching transistors operate in opposite directions.

[0029] Preferably, the controller is further configured to control the second switch tube and the fourth switch tube to operate synchronously, and control the second switch tube and the third switch tube to operate in opposite directions during the closed-loop charging stage.

[0030] Preferably, when the load of the first electronic device is a second electronic device, the second output terminal is used to charge the battery of the second electronic device. The controller is further configured to control the second switching transistor to operate synchronously with the fourth switching transistor, and to control the second switching transistor to operate in the opposite direction to the third switching transistor, when the battery is used to charge the second electronic device. This scenario is applicable when the battery of the first electronic device is used to charge the second electronic device when no adapter is connected to the power supply terminal, for example, when an earphone box is used to charge earphones. This charging mode is a boost charging mode.

[0031] Preferably, the following describes a case where the two output terminals are the second terminal of the second switching tube and the second terminal of the third switching tube. When the second terminal of the third switching tube is connected to the first terminal of the first inductor, the system further includes: a backflow prevention switching tube and a ninth switching tube. The first terminal of the first switching tube is connected to the power supply terminal via the backflow prevention switching tube; the second terminal of the first inductor is connected to the power supply terminal via the ninth switching tube. In this charging scenario, the power supply terminal directly supplies power to the second output terminal, i.e., charging, without any power conversion, thereby improving charging efficiency.

[0032] Preferably, it also includes: a controller; the controller is used to control the anti-backflow switch tube to be turned on and the ninth switch tube to be turned off during the open-loop charging stage; in the closed-loop charging stage, the ninth switch tube is controlled to be turned on or periodically turned on, and the anti-backflow switch tube is controlled to be turned off.

[0033] Preferably, an open-loop buck charging mode suitable for an earphone box and a mobile phone is described below. The controller is further configured to control the first and third switching transistors to operate synchronously, and the second and fourth switching transistors to operate synchronously, during the open-loop charging phase. The first and second switching transistors operate in opposite directions.

[0034] Preferably, the following introduces a closed-loop boost charging mode suitable for the earphone box. The controller is also used to 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 and the second switch tube to operate in opposite directions during the closed-loop charging stage.

[0035] Preferably, the following describes a mode in which the headphone box steps down the voltage to charge the headphones when no adapter is connected to the power supply, for example, in a headphone box charging scenario. When the load of the first electronic device is a second electronic device, the controller is further configured to control the synchronous operation of the first and third switching transistors, the synchronous operation of the second and fourth switching transistors, and the opposite operation of the first and second switching transistors when the battery is used to charge the second electronic device.

[0036] Preferably, the charging circuit described below can operate in the BuckBoost+SC charging mode, and further includes: a tenth switching tube; a first end of the tenth switching tube is connected to the second end of the first inductor, and a second end of the tenth switching tube is grounded.

[0037] Preferably, the controller is further configured to control the ninth switch tube to be periodically turned on, control the ninth switch tube and the tenth switch tube to be alternately turned on, control the fourth switch tube to be turned off, and control the third switch tube to be turned on during the closed-loop buck charging stage.

[0038] Preferably, the controller is also used to control the periodic conduction of the ninth switch tube, control the synchronous operation of the first switch tube, the third switch tube and the tenth switch tube, and control the synchronous operation of the second switch tube, the fourth switch tube and the ninth switch tube in the closed-loop buck-boost charging stage.

[0039] Preferably, the forward and reverse BuckBoost+SC charging scenario described below also 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 second end of the eleventh switch tube serves as the second output end; the controller is further used to control the eleventh switch tube to operate synchronously with the fourth switch tube.

[0040] Preferably, the controller is further used to 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, the first switch tube and the second switch tube to operate in opposite directions, control the tenth switch tube and the third switch tube to operate synchronously, and control the eleventh switch tube and the fourth switch tube to operate synchronously.

[0041] Preferably, a simplified control strategy is introduced below. First, the buck charging control in the simplified control strategy is introduced. The controller is also used to control the tenth switch tube to turn off and control the eleventh switch tube to turn on when the voltage at the second output terminal is less than the voltage at the first output terminal; control the first switch tube and the second switch tube to operate synchronously, control the second switch tube and the fourth switch tube to operate synchronously, and control the first switch tube and the second switch tube to operate in opposite directions.

[0042] Preferably, the boost charging control in the simplified control strategy is introduced below, and the controller is also used to control the first switch tube, the second switch tube and the fourth switch tube to be turned off, control the third switch tube to be turned on, and control the tenth switch tube and the eleventh switch tube to be turned on alternately when the voltage of the second output terminal is greater than the voltage of the first output terminal.

[0043] An embodiment of the present application further provides an electronic device, comprising: a battery and the charging circuit described above; the first end of the charging circuit is used to connect to a power supply, and 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 to a load of the electronic device; the charging circuit is used to convert the electrical energy provided by the power supply to charge the battery and power the load of the electronic device. For example, the electronic device is a mobile terminal such as a mobile phone or a wearable device such as an earphone box.

[0044] It should be noted that the controller controlling the actions of the various switching tubes mentioned in the above embodiments refers to the controller sending a control signal, such as a pulse width modulation (PWM) signal, to the control terminal of each switching tube.

[0045] It can be seen from the above technical solutions that the embodiments of the present application have the following advantages:

[0046] When the charging circuit has a single output terminal, namely, the second terminal of the first switching tube serves as the output terminal, the charging circuit combines the advantages of the high efficiency of the SC circuit with the voltage stabilization provided by the closed-loop control of the Buck circuit. The functions of the open-loop voltage transformer circuit and the closed-loop voltage transformer circuit are integrated into one, achieving a highly integrated charging circuit with a simple structure and ease of implementation. Therefore, the charging circuit provided in this embodiment can improve charging efficiency, thereby achieving fast charging in PC scenarios.

[0047] When the charging circuit has two output terminals, it can be applied to scenarios such as terminal devices 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, realizes high integration of fast charging, and realizes the effective fusion of closed-loop transformer circuit and open-loop transformer circuit. It can utilize both the high efficiency of the open-loop transformer circuit and the voltage stabilization function of the closed-loop transformer circuit. It can be applied to both single-cell batteries and double-cell batteries, and has a wide range of application scenarios, which improves the universality of the charging circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Figure 1 A schematic diagram of a fast charging system located inside a mobile phone provided by prior art;

[0049] Figure 2 A diagram of the HPB structure provided in an embodiment of the present application;

[0050] Figure 3 NVDC architecture diagram provided for the embodiment of this application;

[0051] Figure 4 A schematic diagram of a first embodiment of a charging circuit provided in an embodiment of the present application;

[0052] Figure 5 A schematic diagram of the HPB fast charging architecture provided in an embodiment of the present application;

[0053] Figure 6 For Figure 5 Corresponding to a path diagram;

[0054] Figure 7 For Figure 5 Another corresponding path diagram;

[0055] Figure 8 Schematic diagram of the NVDC fast charging architecture provided in the embodiment of this application;

[0056] Figure 9 A path diagram for NVDC fast charging and boosting provided in an embodiment of the present application;

[0057] Figure 10 For Figure 9 Another corresponding path diagram;

[0058] Figure 11 This is a flow chart of the control method in the HPB mode provided in an embodiment of the present application;

[0059] Figure 12This is a flow chart of the control method under the NVDC mode provided in an embodiment of the present application;

[0060] Figure 13 A schematic diagram of a first embodiment of an electronic device provided in an embodiment of the present application;

[0061] Figure 14 A schematic diagram of another charging circuit provided in an embodiment of the present application;

[0062] Figure 15 A schematic diagram of the first electronic device provided in an embodiment of the present application being an earphone box;

[0063] Figure 16 A schematic diagram of the interior of the earphone box provided in an embodiment of the present application;

[0064] Figure 17 A schematic diagram of another charging circuit provided in an embodiment of the present application;

[0065] Figure 18 for Figure 17 The corresponding path diagram of the open-loop charging phase;

[0066] Figure 19 for Figure 17 A corresponding path diagram for voltage reduction during the CV charging phase;

[0067] Figure 20 for Figure 17 Another path diagram for voltage reduction during the corresponding CV charging phase;

[0068] Figure 21 for Figure 17 A corresponding path diagram for boosting voltage during the CV charging phase;

[0069] Figure 22 for Figure 17 Another path diagram for boosting the corresponding CV charging phase;

[0070] Figure 23 A schematic diagram of another charging circuit provided in an embodiment of the present application;

[0071] Figure 24 A schematic diagram of another charging circuit provided in an embodiment of the present application;

[0072] Figure 25A A schematic diagram of another charging circuit provided in an embodiment of the present application;

[0073] Figure 25B The embodiment of this application provides Figure 25A Another charging circuit diagram based on this;

[0074] Figure 26 for Figure 25BA corresponding working mode diagram;

[0075] Figure 27 for Figure 25B Schematic diagram of another corresponding working mode;

[0076] Figure 28 for Figure 25B The corresponding path diagram when Vbus is not connected to the power supply;

[0077] Figure 29 for Figure 25B The corresponding modal diagram when Q1 and Q3 are turned on;

[0078] Figure 30 for Figure 25B The corresponding modal diagram when Q1 and Q3 are turned off;

[0079] Figure 31 for Figure 25B The corresponding diagram of Q11 being turned off and Q10 being turned on;

[0080] Figure 32 for Figure 25B The corresponding schematic diagram of Q11 being on and Q10 being off;

[0081] Figure 33 This is a schematic diagram of Example 2 of the electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0082] The technical solutions in the embodiments of the present application will be described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, not all of the embodiments. The terms "first", "second", etc. in the following description are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of the present application, unless otherwise specified, the meaning of "multiple" is two or more. In addition, in the present application, directional terms such as "upper" and "lower" may be defined including but not limited to the orientation relative to the schematic placement of the components in the drawings. It should be understood that these directional terms may be relative concepts. They are used for description and clarification relative to each other, and may change accordingly according to changes in the orientation of the components in the drawings.

[0083] In this application, unless otherwise specified or limited, the term "connection" should be understood broadly. For example, "connection" can refer to a fixed connection, a detachable connection, or an integral connection, indicating a communication connection or an electrical connection; it can be a direct wire connection or an indirect connection through an intermediate medium. In addition, the term "coupling" can refer to the method of electrical connection that achieves signal transmission. "Coupling" can refer to a direct electrical connection or an indirect electrical connection through an intermediate medium.

[0084] To help those skilled in the art better understand the technical solutions provided by the embodiments of this application, the following will first introduce the fast charging scenario of a PC battery as an example. Depending on the computer adapter, the architecture of the charging circuit inside the computer varies, and currently mainly includes the following two categories: the first category: Hybrid Power Boost (HPB) mode; the second category: Narrow Voltage Direct Current (NVDC) mode;

[0085] The following first introduces the working principle of the first type of HPB. Figure 2 As shown in FIG. , this figure is a diagram of the HPB architecture provided by an embodiment of the present application. Vin is the input voltage of the charging circuit, i.e., the output voltage of the adapter, which charges the battery Vbat through the charging circuit 30. At the same time, Vin can directly power the computer system.

[0086] The following describes the working principle of the second type of NVDC. Figure 3 This figure shows the NVDC architecture provided by an embodiment of this application. NVDC is suitable for adapters with adjustable output voltage, meaning the output voltage can be within a wide voltage range. Vin charges the battery Vbat through the charging circuit 30 and also provides power to the computer system.

[0087] from Figure 2 and Figure 3It can be seen that, whether it is HPB or NVDC, the charging circuit needs to improve the conversion efficiency of electric energy. The following is an introduction to the technical solution provided by the embodiment of the present application in conjunction with the schematic diagram of a specific charging circuit, which can truly realize fast charging in PC scenarios and meet the system power supply requirements of the PC. The embodiment of the present application provides a charging circuit with high efficiency and suitable for PC application scenarios. 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. When the charging circuit works at the optimal efficiency point, the charging voltage requirement of the PC battery can be met. The charging voltage range of the PC battery is about 15V, for example, between 12V-20V. The voltage transformation ratio corresponding to the optimal 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 reduced to about 15V. The charging circuit provided by the embodiment of the present application is introduced in detail below in conjunction with the accompanying drawings.

[0088] Charging circuit embodiment 1:

[0089] See also Figure 4 This figure is a schematic diagram of a charging circuit provided in an embodiment of the present application. The charging circuit provided in this embodiment includes: a first switch tube Q1, a second switch tube Q2, a third switch tube Q3, a fourth switch tube Q4, a first capacitor Cfly, a second capacitor Cmid, and a first inductor L1. The first end of the first 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, 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 two ends of the first capacitor 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 via the second capacitor Cmid. 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 serves as the charging output end Vout for charging the battery of the electronic device. In actual implementation, the controller outputs drive signals to Q1-Q4. It can output four outputs, or use a single drive signal for switches in the same conduction state. When the charging circuit operates in buck charging mode, during each switching cycle, the conduction states of Q1 and Q2 are opposite and complementary, while the conduction states of Q1 and Q3 are the same, and the conduction states of Q2 and Q4 are the same.

[0090] 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 approximately 4:3. Therefore, when the adapter input of the PC is about 20V, the purpose of reducing the voltage to about 15V is achieved, 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 the advantages of fast voltage regulation of the closed-loop control of the Buck circuit, and integrates the open-loop transformer circuit and the closed-loop transformer circuit into one, thereby achieving a high degree of integration of the charging circuit, and the structure is simple and easy to implement. Therefore, the charging circuit provided in this embodiment can improve the charging efficiency, thereby achieving fast charging in the PC scenario.

[0091] The following describes the working principles of the Hybrid Power Boost (HPB) mode and the Narrow Voltage Direct Current (NVDC) mode in PC scenarios, respectively, with reference to the accompanying figures. Figure 5 , this figure is a schematic diagram of the HPB fast charging architecture provided in an embodiment of the present application. The charging circuit provided in this embodiment may also include: an anti-backflow switch tube RBFET and a fifth switch tube Q5; the first end of the first switch tube Q1 is connected to the adapter through the anti-backflow switch tube RBFET, that is, connected to Vbus; the function of the anti-backflow switch tube RBFET is mainly to prevent the current on the system power supply SYS side from flowing to the Vbus side when it is turned off. The anti-backflow switch tube RBFET can be implemented by a switch tube to prevent unidirectional backflow. It should be noted that when the anti-backflow switch tube RBFET is specifically implemented, it can also be implemented by using two back-to-back switch tubes, Figure 5 The anti-backflow switch tube RBFET is realized by connecting two switch tubes in series. That is, when the anti-backflow switch tube RBFET is turned off, the function of complete shutdown is achieved, that is, no current flows in both directions.

[0092] The second end of the first inductor L1 is connected to the system power supply terminal SYS of the electronic device via a fifth switch Q5. Taking a PC as an example, 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 terminal SYS of the PC. The first end of the first switch Q1 is directly connected to the system power supply terminal SYS, that is, SYS is directly connected to Vbus via the backflow prevention switch RBFET. When the adapter is plugged into the PC, the adapter can directly power the system power supply terminal SYS of the PC, improving power supply efficiency. The charging circuit provided in this embodiment also includes a controller (not shown). The controller is specifically configured to control the fifth switch Q5 to be disconnected when the adapter is connected, that is, when Vbus is connected to an external power source, disconnecting Vbat from SYS. When the adapter is not connected, that is, when Vbus is not connected to an external power source, the controller controls the fifth switch Q5 to be closed, connecting Vbat to SYS. For example, the battery in the PC supplies power to the system power supply terminal of the PC. It should be noted that when Q5 is disconnected, it can operate in a unidirectional conduction mode because Q5 includes a parallel diode, which allows conduction from Vbat to SYS. When the product is implemented, Q1-Q4 can be integrated into a single chip or implemented independently, and this is not specifically limited in the embodiments of this application. When the battery is fully charged and Vbus is still connected to the adapter, Q1-Q4 can be controlled to be disconnected, RBFET is closed, Q5 is disconnected, and Vbus directly powers SYS.

[0093] The working principle of the embodiment of the present application is described below with reference to the path diagram. Figure 6 and Figure 7 , the figure is with Figure 5 The corresponding path diagram. Figure 6 This corresponds to the path diagram when Q1 and Q3 are turned on and Q2 and Q4 are turned off. Figure 7 The corresponding path diagram is when Q1 and Q3 are off and Q2 and Q4 are on. This can be called path 1, which is the step-down path.

[0094] The controller controls the charging circuit to operate in buck mode. Each switch can be a controllable switch. That is, in addition to the first and second terminals, each switch also includes a third terminal, namely, a control terminal. For example, for a MOS transistor, the control terminal is the gate. The controller can output a drive signal to control the switching state of each switch, namely, on or off. When charging the battery using an adapter, the first switch Q1 and the third switch Q3 are controlled to operate synchronously, that is, the drive signals for Q1 and Q3 can be in phase. The second switch Q2 and the fourth switch Q4 are controlled to operate synchronously, that is, the drive signals for Q2 and Q4 can be in phase. The first switch Q1 and the second switch Q2 operate in opposite directions, that is, the drive signals for Q1 and Q2 are complementary. Synchronous operation of the switches means that they are turned on and off simultaneously. Opposite operation of the switches means that when one switch is turned on, the other is turned off, and the two switches are not turned on at the same time.

[0095] from Figure 6 It can be seen that when Q1 and Q3 are both turned on and Q2 and Q4 are both turned off, Vbus directly supplies power to SYS, Vbus charges Vbat through Q1 and L1, and at the same time Vbus charges Cfly and Cmid through the path formed by Q1 and Q3. Figure 7 It can be seen that when Q1 and Q3 are both off and Q2 and Q4 are both 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 transmission gain from Vbus to Vbat is:

[0096]

[0097] Since D is less than 1, Vbus > Vbat, and 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 HPB mode for PC scenarios. The following describes the implementation process of the charging circuit provided by the embodiment of the present application in NVDC mode for PC scenarios.

[0098] See also Figure 8 , which is a schematic diagram of the NVDC fast charging architecture provided by the 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 including Figure 4 In addition to the components shown in FIG, the device further includes: a reverse flow prevention switch tube RBFET and a charge and discharge control switch tube BATFET1; wherein the reverse flow prevention switch tube RBFET can be connected to Figure 5 The anti-backflow switch tube RBFET is the same as that in the embodiment, and will not be repeated here, that is, the first end of the first switch tube Q1 is connected to the power supply terminal Vbus through the anti-backflow switch tube RBFET.

[0099] The second end of the first inductor L1 is connected to the battery through the charge and discharge control switch tube BATFET1, that is, connected to the charging terminal Vbat. The second end of the first inductor L1 is connected to the system power supply terminal SYS of the electronic device. It should be noted that the NVDC mode is different from the HPB mode. Figure 5 and Figure 8 It can be found that the connection relationship of SYS is different.

[0100] The charging circuit provided in this embodiment also includes a controller (not shown). The controller is configured to control the charge-discharge control switch BATFET1 to conduct when the adapter is connected, i.e., when the power supply terminal Vbus is charging the battery; and to control the charge-discharge control switch BATFET1 to disconnect when the battery is fully charged. In this embodiment, Vbus can also power SYS via Q1 and L1.

[0101] The controller is also used to control the first switch tube Q1 and the third switch tube Q3 to operate synchronously, and the second switch tube Q2 and the fourth switch tube Q4 to operate synchronously when the power supply terminal Vbus is used to charge the battery, that is, when the voltage provided by the adapter is stepped down to charge the battery, so that the first switch tube Q1 and the second switch tube Q2 operate in opposite directions. The synchronous operation and opposite operation here are the same as those in the HPB mode and will not be described in detail here. This mode is suitable for 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 the same as Figure 5 The corresponding ones are similar and will not be repeated here.

[0102] Next, continue to combine Figure 8 、 Figure 9 and Figure 10 This article mainly introduces the working principle of boost charging under the NVDC fast charging architecture. Figure 9 , This figure is a path diagram of NVDC fast charging and boosting provided by the embodiment of this application. Among them, Figure 9 is the path diagram corresponding to when Q1 and Q4 are closed, Figure 10 This is the path diagram corresponding to when Q1 and Q4 are turned off.

[0103] When NVDC fast charging uses a boost circuit to achieve charging, the charging circuit also 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 second end of the sixth switch tube Q6 is connected to the second end of the first inductor L1; the battery is charged after the power supply terminal Vbus is boosted, that is, the adapter voltage is boosted to charge the battery, which is suitable for the adapter voltage being lower than the battery voltage, for example, the adapter output voltage is 5V instead of 20V. That is, the charging circuit provided by this embodiment is compatible with low-voltage adapters and can charge PC batteries. During step-down charging, Q6 remains in a disconnected state, that is, Q6 is equivalent to being stripped from the charging circuit and has no function. The controller is also used to control the second switch tube Q2 and the third switch tube Q3 to be disconnected when charging the battery Vbat after Vbus is boosted, control the first switch tube Q1 and the fourth switch tube Q4 to operate synchronously, and control the first switch tube Q1 and the sixth switch tube Q6 to operate in opposite directions.

[0104] For the convenience of subsequent description, control strategy 2 is introduced. Control strategy 2 means: Q2 and Q3 remain disconnected, Q1 and Q4 operate synchronously, the driving pulses of Q1 and Q6 are inverted, and the duty cycle of Q1 is D. Figure 9 As shown, Q1 and Q4 are turned on, Q6 acts opposite to Q1, Q6 is turned off, Vbus charges Vbat through Q1 and L1, and supplies power to SYS and charges Cfly. The current direction can be seen from the current path iL.

[0105] like Figure 10 As shown, Q1 and Q4 are turned off, Cfly discharges to charge Vbat and supplies power to SYS. The current direction can be seen from the current path iI. When the duty cycle of the drive signal of Q1 is D, the gain of the charging circuit is as follows:

[0106]

[0107] That is, the voltage range of Vbat is (Vin, +∞), realizing closed-loop boost conversion.

[0108] In addition, the charging circuit can also work in reverse, that is, when there is no adapter connected to the power supply terminal Vbus, the battery is used as the power supply, 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:

[0109]

[0110] That is, the output voltage range of Vbus is (0, Vbat), realizing closed-loop step-down conversion.

[0111] 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 to the Vbus end. Vbus can be used as a power output end of the computer. For example, the PC battery can be used to power the mouse, that is, Vbat outputs power to Vbus.

[0112] The HPB fast charging architecture provided in the above embodiments is generally applicable to the case where the output of the adapter is a fixed voltage, that is, the fixed voltage of the adapter is greater than the battery voltage. Therefore, the charging circuit operates in the buck mode to quickly charge the battery. The NVDC fast charging architecture provided in this embodiment is compatible with different situations of the adapter and can operate in both buck mode and boost mode. The control method corresponding to the charging circuit provided in the embodiment of the present application is described in detail below with reference to the accompanying drawings. The above charging circuit provided in the embodiment of the present application can also select its charging control strategy and can operate in performance priority charging mode or fast charging priority mode.

[0113] See also Figure 11 , which is a flow chart of the charging control method provided by an embodiment of the present application. The control method provided by this embodiment includes: S1101: Obtaining a priority charging mode. If the performance priority charging mode is selected, execute S1102; if the fast charging priority mode is selected, execute S1103; S1102: Configuring the adapter voltage to the maximum value; S1103: Dynamically adjusting the adapter voltage based on the battery voltage. Therefore, the control method provided by the embodiment of the present application can achieve a maximum balance between system performance and charging performance, and the controller can select a control strategy as needed.

[0114] The controller can be implemented by an application processor (AP), another processor, or a logic control circuit, and is not specifically limited in the embodiments of the present application, as long as it can complete the above-mentioned control of the charging circuit. The controller can include hardware or a combination of hardware and software.

[0115] The following describes the control strategy of the PC's NVDC fast charging architecture, that is, the control method, see Figure 12 This figure is a flow chart of the control method under the NVDC mode provided by an embodiment of the present application. S1201: Detect the adapter type and the maximum output voltage of the Vbus terminal. In specific implementation, the PC can communicate with the adapter through a handshake communication protocol to obtain the adapter type and the maximum output voltage of the adapter.

[0116] S1202: When the maximum voltage of the adapter is greater than the battery voltage, the charging circuit is configured to be in a buck charging mode. For example, the voltage output by the adapter is approximately 20V, which is greater than the battery voltage. Therefore, the charging circuit is configured to be in a buck mode to charge the battery.

[0117] S1203: When the maximum voltage of the adapter is less than the battery voltage, the charging circuit is configured to operate in a boost charging mode. For example, the voltage output by the adapter is approximately 5V, which is less than the battery voltage. Therefore, the charging circuit is configured to operate in a boost charging mode to charge the battery. The types of the various switching transistors in the charging circuits provided in the above embodiments of the present application are not specifically limited. For example, they may be implemented as MOS transistors, such as Q1-Q4 which may be NMOS transistors. The gate of the MOS transistor is used to receive a control signal from a controller, such as a PWM signal output by the controller.

[0118] Specifically, the controller may include a processor and a memory. The memory is a computer-readable storage medium, so the embodiment of the present application also provides a computer-readable storage medium, including instructions or computer programs, which, when run on a computer or controller, enable the computer or controller to execute the charging control method described above, i.e. Figure 11 and Figure 12 The method steps described are not repeated here. The computer instructions are also a computer program product. Processors include, but are not limited to, CPUs (Central Processing Units), GPUs (Graphics Processing Units), or DSPs (Digital Signal Processing).

[0119] Through the description of the above embodiments, it can be known that those skilled in the art can clearly understand that all or part of the steps in the above embodiment methods 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, which can be stored in a storage medium, such as a read-only memory (ROM) / RAM, a magnetic disk, an optical disk, etc., and includes a number of program codes or instructions for enabling a computer device (which can be a personal computer, a server, or a network communication device such as a router) to execute the methods described in each embodiment or certain parts of the embodiments of the present application.

[0120] In addition, the embodiment of the present application further provides a device, comprising a plurality of units, each unit being configured to execute corresponding steps of the previous embodiment, for example Figure 11 and Figure 12 The multiple units are functional units and can be implemented in the form of software, hardware, or a combination of hardware and software, which is not limited in this embodiment.

[0121] Electronic device embodiment 1:

[0122] Based on the charging circuit provided in the above embodiment, the present application also provides an electronic device, which includes the charging circuit provided in the above embodiment and a battery. Figure 13 , which is a schematic diagram of an electronic device embodiment 1 provided by an embodiment of the present application. The electronic device provided in this embodiment, for example, may be a PC, and the electronic device may include the charging circuit 1000 described in the above embodiment, which may be a charging circuit in the HPB fast charging mode or a charging circuit in the NVDC fast charging mode.

[0123] 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 supply terminal of the battery 2000. When the electronic device is a PC, the battery is the PC's battery. The charging circuit 1000 is used to convert the electrical energy provided by the adapter to charge the battery 2000. When the electronic device is a PC, since the PC includes the charging circuit provided by the above embodiment, the charging circuit can achieve closed-loop fast charging. Moreover, since the charging circuit includes an SC circuit, it can improve charging efficiency and truly achieve efficient and fast closed-loop charging control.

[0124] The charging circuit described 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, a smart terminal can be a mobile phone, a tablet computer, etc., and the wearable device can be a Bluetooth headset, a watch or VR, etc. The specific types of smart terminals and wearable devices are not specifically limited in the embodiments of this application.

[0125] Charging circuit embodiment 2:

[0126] See also Figure 14This figure is a schematic diagram of another charging circuit provided in an embodiment of the present application. The charging circuit provided in this embodiment includes: a first switch tube Q1, a second switch tube Q2, a third switch tube Q3, a fourth switch tube Q4, a first capacitor Cfly, and a first inductor L1. The first end of the first switch tube Q1 is used to connect to a power supply terminal, the second end of the first switch tube Q1 is connected to the first end of the second switch tube Q2, 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 two ends of the first capacitor 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 serves as a first output terminal Vout2 for charging a battery of a first electronic device. The charging circuit is located inside the first electronic device. The second end of the first switch tube Q1 is connected to the first end of the first inductor L1, or the second end of the third switch tube Q3 is connected to the first end of the first inductor L1. The second end of the first inductor L1 serves as a second output terminal, i.e., a load power supply terminal of the first electronic device.

[0127] It should be noted that the charging circuit includes two output terminals, which can be Vout1 and Vout2, or Vout2 and Vout3. The two output terminals can simultaneously power two different loads. That is, the first output terminal is Vout2, and the second output terminal can be Vout1 or Vout3.

[0128] When the first electronic device is a mobile phone, the load of the first electronic device can be the power circuit inside the mobile phone. When the first electronic device is an earphone case, the load of the first electronic device can be the Bluetooth headset inside the earphone case. That is, the adapter charges both the battery of the earphone case and the battery of the headset inside the earphone case. In this case, the Bluetooth headset serves as the second electronic device. Through this charging circuit, the adapter can simultaneously charge the headset case and the headset, that is, charge the first and second electronic devices simultaneously.

[0129] See also Figure 15 This figure is a schematic diagram of an embodiment of the present application in which the first electronic device is an earphone box. The housing of the earphone box 401 is provided with a power supply terminal (not shown in the figure), i.e., a charging interface. The earphone box 401 can be connected to an adapter 402 through this power supply terminal. Once the adapter 402 is connected to a power source, the battery of the earphone box 401 can be charged. Simultaneously, the earphones 403 inside the earphone box 401 can also be charged.

[0130] See also Figure 16, which is a schematic diagram of the interior of an earphone case provided by an embodiment of the present application. The earphone case can accommodate two independent earphones, namely a left earphone and a right earphone. When the earphones are placed in the earphone case, the charging terminal 301 of the earphone case connects to the power receiving terminal 302 of the earphones, thereby completing the charging of the earphones. At this time, the earphones act as the load of the earphone case, that is, as a second electronic device. The adapter can charge the earphone case (the first electronic device) and the earphones (the second electronic device) at the same time.

[0131] The following takes Vout1 and Vout2 as the two output terminals of the charging circuit as an example for introduction. Figure 17 , this figure is a schematic diagram of another charging circuit provided in an embodiment of the present application. The charging circuit provided in this embodiment can be applied to smart terminals such as mobile phones, as well as wearable devices such as Bluetooth headsets. 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 serves as the second output end Vout1; Vout1 is directly connected to SYS, and also includes: a backflow 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 end Vbus through the backflow prevention switch tube RBFET; the seventh switch tube Q7 is an optional device, 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 to ensure that a bidirectional shutdown function can be achieved; it should be noted that, Figure 17 In the figure, Q2 and Q7 are drawn as two independent switch tubes. In actual implementation, Q2 and Q7 can be a physical switch. The physical switch can be realized by connecting two tubes in reverse series or by switching the substrate. Figure 17 The purpose of Q5 is to achieve a bidirectional shutoff function when turned off. A first end of the fifth switch tube Q5 is connected to the second end of the first inductor L1, and a second end of the fifth switch tube Q5 is connected to the first output end.

[0132] The charging circuit provided in this embodiment may include a controller (not shown in the figure) configured to control the seventh switch Q7 and the second switch Q2 to operate synchronously, i.e., to turn them on or off simultaneously. During the open-loop charging phase, the controller controls the fifth switch Q5 to be off, i.e., Q5 disconnects SYS from Vout2 during the open-loop charging phase. During the constant-voltage closed-loop charging phase, the controller controls the fifth switch Q5 to be on, i.e., Vout1 and Vout2 are connected together via Q5 during the closed-loop charging phase.

[0133] The controller is further configured to, during the open-loop charging phase, control the synchronous operation of the first switch Q1 and the third switch Q3, and the synchronous operation of the second switch Q2 and the fourth switch Q4, with the first switch Q1 and the second switch Q2 operating in opposite directions, 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, i.e., SYS. For the convenience of subsequent description, the concept of control strategy is introduced, where control strategy 1 refers to two operating modes: synchronous operation of Q1 and Q3, synchronous operation of Q2 and Q4, and phase opposition of Q1 and Q3, with Q1 and Q3 operating in opposite directions, and Q1 conducting with a duty cycle of D.

[0134] See also Figure 18 , the figure is Figure 17 The corresponding path diagram for the open-loop charging phase. During the open-loop charging phase, the power supply path for Vout1, or SYS, is from Vbus to SYS. This path is identical to the forward operation of Path 1 in the first charging circuit embodiment and is not described here. The power supply path for Vout2 is from Vbus to Vout2, which is identical to the forward operation of Path 2 in the first charging circuit embodiment. For the above open-loop charging phase, the charging path is also applicable to mobile phones, headphones, and other application scenarios.

[0135] The following is a detailed description of the working principle of the closed-loop charging stage with reference to the accompanying drawings. Figure 19 and Figure 20 This describes the case where both the phone and the headset box use single-cell batteries. This means the adapter voltage is greater than the phone's battery voltage, requiring the adapter voltage to be stepped down to charge the phone's battery. During the closed-loop charging phase, Q5 is on, connecting SYS to Vout2.

[0136] See also Figure 19 and Figure 20 , the figure is Figure 17 The corresponding closed-loop charging stage voltage reduction path diagram. Figure 19 Schematic diagram of Q1 and Q3 both turned on and Q4 turned off. Figure 20 Schematic diagram of Q1 and Q3 being turned off and Q4 being turned on. During the closed-loop charging phase, Q2 and Q7 remain disconnected. The controller is further configured to, during the closed-loop charging phase, control the second switch tube Q2 and the optional seventh switch tube Q7 to be disconnected, control the fifth switch tube Q5 to be closed, control the first switch tube Q1 and the third switch tube Q3 to operate synchronously, and control the first switch tube Q1 and the fourth switch tube Q4 to operate in opposite directions. The specific path can be found in the current i in the figure. L direction.

[0137] from Figure 19It can be seen that when Q1 and Q3 are closed, Vbus supplies power to SYS through Q1 and L1, and charges Vbat and Cfly at the same time. Figure 20 It can be seen that when Q1 and Q3 are turned off, Cfly supplies power to SYS and Vbat, that is, charging. At this time, the duty cycle of Q1's drive signal is D;

[0138] The gain of the charging circuit is:

[0139]

[0140] Vsys is the voltage of SYS, meaning the Vsys output voltage range is (0.5Vbus, Vbus). At this point, Vbat is equal to Vsys, and the proportional relationship between Vbat and Vbus is as described above, which is omitted here. For ease of description, this control strategy is defined as Control Strategy 3: Q2 and Q7 are off, Q1 and Q3 are synchronized, and Q1 and Q4 are in opposite phases.

[0141] First combine Figure 21 and Figure 22 This describes the situation where the mobile phone and the headset box have two batteries, that is, the adapter voltage is lower than the battery voltage of the mobile phone, and the adapter voltage needs to be boosted to charge the battery of the mobile phone or other terminal device. Figure 21 and Figure 22 , the figure is Figure 17 The corresponding closed-loop charging stage boost path diagram. Among them, Figure 21 Schematic diagram of Q1 and Q4 both turned on and Q3 turned off. Figure 22 This is a schematic diagram showing Q1 and Q4 both off and Q3 on. During the closed-loop charging phase, Q2 and Q7 remain off. The controller is further configured to, during the closed-loop charging phase, control the second switch Q2 and the optional seventh switch Q7 to be off, control the fifth switch Q5 to be on, control the first switch Q1 and the fourth switch Q4 to operate synchronously, and control the first switch Q1 and the third switch Q3 to operate in opposite directions.

[0142] Figure 21 and Figure 22 The corresponding charging circuit gain is:

[0143]

[0144] Theoretically, the Vsys output voltage range is (Vbus, +∞), indicating that this charging circuit implements a boost conversion. For the convenience of subsequent description, this control strategy is defined as Control Strategy 4: Q2 and Q7 are turned off, Q1 and Q4 are synchronized, and Q1 and Q3 are in opposite phases.

[0145] In the above scenario of charging a mobile phone and a headphone case, the adapter's output voltage is generally around 5V. 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, if the first electronic device is a headphone case and the second electronic device is headphones, and the headphones are in the headphone case, the headphones serve as the headphone case's load.

[0146] The following describes how the battery of a first electronic device can charge a second electronic device when the power supply of the charging circuit is not connected to an adapter, that is, when there is no external power supply connected to Vbus. This controller is also used to control the charging circuit to boost the battery voltage to charge the second electronic device. It controls the second switch Q2 to operate synchronously with the fourth switch Q4, and controls the second switch Q2 to operate in the opposite direction to the third switch Q3. At this time, Q5 is closed and conductive, and Q2 and Q7 operate simultaneously. Q2 and Q7 can be considered a single switch, or bundled together. This means that Vbat is boosted to charge SYS. In the headphone box scenario, the headphone box's battery charges the headphones.

[0147] The charging circuit provided in this embodiment can be applied to mobile terminals and wearable devices, achieving high integration of fast charging and effective fusion of closed-loop transformer circuits and open-loop transformer circuits. It can utilize both the high efficiency of open-loop transformer circuits and the voltage stabilization function of closed-loop transformer circuits. It can be applied to both single-cell batteries and dual-cell batteries, with a wide range of application scenarios, thus improving the universality of the charging circuit. In addition, 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 use the charging circuit to charge the first and second electronic devices at the same time.

[0148] Charging circuit implementation three:

[0149] See also Figure 23 , which 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 terminals is different. Figure 23It can be seen that 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 serves as the second output terminal Vout1, it also includes: an anti-backflow switch tube RBFET and an 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 to the power supply terminal Vbus, and the second end of the eighth switch tube Q8 is connected to the second output terminal Vout1. In this embodiment, Vout1 and Vout2, that is, Vout1 and Vbat, are not directly connected together through a switch tube. Only one of the anti-backflow switch tube RBFET and the eighth switch tube Q8 is turned on at a time; they are not turned on at the same time.

[0150] The charging circuit provided in an embodiment of the present application also includes: a controller (not shown in the figure); the controller is used to control the anti-backflow switch tube RBFET to be turned on and the eighth switch tube Q8 to be turned off during the open-loop charging stage; in the constant-voltage closed-loop charging stage, the eighth switch tube Q8 is controlled to be turned on and the anti-backflow switch tube RBFET is controlled to be turned off.

[0151] For the scenarios of mobile phones and headphones, the paths are the same during the open-loop charging stage. That is, the controller is also used to control the synchronous operation of the first switch tube Q1 and the third switch tube Q3, and the synchronous operation of the second switch tube Q2 and the fourth switch tube Q4 during the open-loop charging stage. The actions of the first switch tube Q1 and the second switch tube Q2 are opposite. The actions of Q1-Q4 are similar to those in the first embodiment of the charging circuit and will not be repeated here. It should be noted that the open-loop charging stage is the open-loop fast charging stage, and the closed-loop charging stage is the closed-loop fast charging stage.

[0152] During the closed-loop charging phase, the controller is further configured to synchronize the second switch Q2 and the fourth switch Q4, and to control the second switch Q2 and the third switch Q3 to operate in opposite directions. When the adapter is not connected, that is, when Vbus is not connected to an external power source, and when the electronic device is loaded by a second electronic device, the second output terminal is used to charge the battery of the second electronic device. The controller is further configured to synchronize the second switch Q2 and the fourth switch Q4, and to control the second switch Q2 and the third switch Q3 to operate in opposite directions, when the battery is used to charge the second electronic device. This means that Vbat outputs power in the opposite direction of Vout1.

[0153] When the charging path is Vbat outputting power in reverse to Vout1, the gain is:

[0154]

[0155] With Vout2 as input and Vout1 as output, closed-loop step-up conversion is implemented. The output voltage range of Vout1 is (Vout2, 2*Vout2), achieving step-up conversion. Conversely, when Vout1 is input and Vout2 is output, closed-loop step-down conversion is implemented. The output voltage range of Vout2 is (0.5*Vout1, Vout1), achieving step-down conversion. This embodiment is also applicable to scenarios where the adapter outputs a voltage of approximately 5V.

[0156] This solution can be applied to mobile terminals and wearable devices, achieving high integration of fast charging, and realizing the effective integration of closed-loop transformer circuit and open-loop transformer circuit. It can not only utilize the high efficiency of the open-loop transformer circuit, but also utilize the voltage stabilization function of the closed-loop transformer circuit. It can be applied to a wide range of single-cell battery application scenarios of various devices, that is, it improves the universality of the charging circuit. In addition, 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 charge the first electronic device and the second electronic device at the same time using the charging circuit. The charging circuit provided in this embodiment is simpler to implement and easier to control than the second charging circuit embodiment. In particular, when Vout1 is powered, it can be powered directly without power conversion, so the charging efficiency is higher.

[0157] Charging circuit embodiment 4:

[0158] See also Figure 24 , which is a schematic diagram of another charging circuit provided in an embodiment of the present application. The two output terminals in this embodiment are different from those in the second and third embodiments of the charging circuit. The first output terminal of the two output terminals in this embodiment is Vout2, and the second output terminal is Vout3, while the two output terminals in the second and third embodiments of the charging circuit 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 when the battery is two batteries connected in series, for example, a mobile phone includes two batteries connected in series, and the output voltage of the adapter is 5V, which is not enough to meet the charging needs of the two batteries. The charging circuit is required to boost the 5V battery and 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. The same as the third embodiment of the charging circuit is that the two output terminals are not connected together through a switch tube.

[0159] from Figure 24It can be seen that when the second end of the second switch tube Q3 is connected to the first end of the first inductor L1, and the second end of L1 serves as the second output end Vout3, it also includes: an anti-backflow switch tube RBFET and a ninth switch tube Q9; when the second end of the third switch tube Q3 is connected to the first end of the first inductor L1, the first end of the first switch tube Q1 is used to connect to the power supply end through the anti-backflow switch tube RBFET; the second end of the first inductor L1 is connected to the power supply end through the ninth switch tube Q9. Similarly, in this embodiment, in the fast charging scenario, only one of the anti-backflow switch tube RBFET and the ninth switch tube Q9 is turned on at the same time, that is, both are not turned on at the same time.

[0160] The charging circuit provided in this embodiment may further include: a controller (not shown); the controller is used to control the various operating modes of the charging circuit. The controller is configured to control the conduction of the anti-backflow switch RBFET and the disconnection of the ninth switch Q9 during the open-loop charging phase; and to control the conduction of the ninth switch Q9 and the disconnection of the anti-backflow switch RBFET during the constant-voltage closed-loop charging phase. That is, during the closed-loop charging phase, Vbus directly supplies power to Vout3 through the closed Q9, without requiring conversion via the switch and inductor. This improves the power supply efficiency of Vout3, reduces power loss, and thus improves the charging efficiency of Vout3.

[0161] The following introduces Figure 24 Possible charging paths.

[0162] Path 4:

[0163] From Vbus to Vout3, this charging path belongs to the cascaded architecture of the SC circuit and the Buck circuit, and the transmission gain is

[0164]

[0165] That is, the forward direction from Vbus to Vout3 is a closed-loop buck mode, and the reverse direction from Vout3 to Vbus is a closed-loop boost mode.

[0166] Path Five:

[0167] The control strategy for the Vout2-Vout3 charging path is: Q1 and Q3 operate synchronously, Q2 and Q4 operate synchronously, Q1 and Q2 operate in opposite phases, and the duty cycle of Q1 is D. Therefore, the path from Vout2 to Vout3 is a Buck configuration, and the path from Vout3 to Vout2 is a Boost configuration. The controller is further configured to control the synchronous operation of the first switch Q1 and the third switch Q3, and the synchronous operation of the second switch Q2 and the fourth switch Q4 during the open-loop charging phase, with the first switch Q1 and the second switch Q2 operating in opposite directions. The controller is further configured to control the synchronous operation of the first switch Q1 and the third switch Q3, and the synchronous operation of the second switch Q2 and the fourth switch Q4 during the closed-loop charging phase, with the first switch Q1 and the second switch Q2 operating in opposite directions. From the above analysis, it can be seen that the charging circuit provided in this embodiment has identical control strategies for Q1-Q4 during both the open-loop and closed-loop charging phases, with only the duty cycles differing.

[0168] The following examples illustrate scenarios using a mobile phone and a headphone case. During the open-loop charging phase of the phone, the RBFET is on and Q9 is off, performing forward operation similar to Path 2 described in the previous embodiment. During the closed-loop charging phase of the phone, or when a 5V adapter is connected, the RBFET is off and Q9 is on, performing reverse boost charging similar to Path 5 described above.

[0169] In the headphone box application scenario, the headphone box battery is connected to Vout2, and the headphones are connected to Vout3. During the open-loop charging phase, SC voltage regulation is supported, charging both the headphone box and the headphones simultaneously. RBFET is on, Q9 is off, and forward operation is performed simultaneously according to Path 2 and Path 4, i.e., buck charging mode. During the closed-loop charging phase, or when a 5V adapter is connected, Vbus is configured to 5V, RBFET is off, Q9 is on, and Vbus = 5V directly charges the headphones. The headphone box charging can follow the reverse Boost operating mode described in Path 5 above, i.e., boost charging mode.

[0170] When the adapter is not connected, that is, when Vbus is not in place, the headphone box battery charges the headphones in forward Buck mode (i.e., step-down charging mode) according to path 5 described above. Specifically, when the load of the first electronic device is a second electronic device, the controller is further configured to control the synchronous operation of the first switch Q1 and the third switch Q3, the synchronous operation of the second switch Q2 and the fourth switch Q4, and the opposite operation of the first switch Q1 and the second switch Q2, while charging the second electronic device using the battery.

[0171] The charging circuit provided in this embodiment can operate in both open-loop charging mode and closed-loop charging mode, and can operate in both buck charging mode and boost charging mode. In addition, the second output terminal is connected to the power supply terminal through a 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 the intermediate power conversion link, thereby reducing power consumption and improving charging efficiency. Because the charging circuit can operate in reverse boost mode, it can be applied to scenarios where multiple batteries are connected in series in mobile terminals such as mobile phones, such as charging scenarios where two batteries are connected in series, and thus can be compatible with different adapters to meet the charging needs of different mobile terminals and wearable devices.

[0172] Charging circuit embodiment 5:

[0173] See also Figure 25A , this figure is a schematic diagram of another charging circuit provided in an embodiment of the present application. The difference between this embodiment and the fourth embodiment of the charging circuit is that a 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 achieved. The charging circuit provided in this embodiment is suitable for both single-cell battery scenarios and dual-cell battery scenarios, and is suitable for charging the battery of a mobile terminal. It is located inside the mobile terminal, for example, for charging the battery of a mobile phone. The first output end of the charging circuit provided in this embodiment is Vout2, and the second output end is Vout3. That is, the charging circuit provided in this embodiment adds: a tenth switch tube Q10; the first end of the tenth switch tube Q10 is connected to the second end of the first inductor L1, and the second end of the tenth switch tube Q10 is grounded.

[0174] In the charging circuit provided in this embodiment, during the open-loop charging stage and the closed-loop boost charging stage, the controller is configured to control the first switch tube Q1 and the third switch tube Q3 to operate synchronously, control the second switch tube Q2 and the fourth switch tube Q4 to operate synchronously, and control the first switch tube Q1 and the second switch tube Q2 to operate in opposite directions.

[0175] It should be noted that the control of the ninth switch tube Q9 and the anti-backflow switch tube RBFET is specifically as follows: the controller is used to control the anti-backflow switch tube RBFET to be turned on and the ninth switch tube Q9 to be turned off during the open-loop charging stage; in the closed-loop charging stage, the ninth switch tube Q9 is controlled to be turned on or periodically turned on, and the anti-backflow switch tube RBFET is controlled to be turned off.

[0176] It should be noted that the closed-loop charging phase in this embodiment includes a closed-loop boost charging phase, a closed-loop buck charging phase, and a closed-loop buck-boost charging phase. The controller's control strategy for Q9 is as follows: during the closed-loop boost charging phase, Q9 is controlled to be continuously on; during the closed-loop buck charging phase and the closed-loop buck-boost charging phase, Q9 is controlled to be periodically on.

[0177] The control strategy for the closed-loop boost charging stage is:

[0178] The controller is further used to control the ninth switch tube Q9 to be always on, control the tenth switch tube Q10 to be always off, control the first switch tube Q1 and the third switch tube Q3 to operate synchronously, and control the second switch tube Q2 and the fourth switch tube Q4 to operate synchronously during the closed-loop boost charging stage.

[0179] The control strategy for the closed-loop buck charging stage is: the controller is also used to control the ninth switch tube Q9 to be periodically turned on, control the ninth switch tube Q9 and the tenth switch tube Q10 to be alternately turned on, control the fourth switch tube Q4 to be turned off, and control the third switch tube Q3 to be turned on.

[0180] The control strategy for the closed-loop buck-boost charging stage is:

[0181] The controller is further used to control the periodic conduction of the ninth switch tube Q9, control the synchronous operation of the first switch tube Q1, the third switch tube Q3 and the tenth switch tube Q10, and control the synchronous operation of the second switch tube Q2, the fourth switch tube Q4 and the ninth switch tube Q9 during the closed-loop buck-boost charging stage.

[0182] See also Figure 25B , which is provided in the embodiment of the present application Figure 25A The difference between this embodiment and the fourth embodiment of the charging circuit is that two switch tubes, namely two controllable switch tubes, are added. By changing the working state of the controllable switch tubes, more working modes can be achieved. Figure 25B and Figure 25A Compared with the previous embodiment, a controllable switch tube, Q11, is added.

[0183] The charging circuit provided in this embodiment is applicable to both single-cell and dual-cell battery scenarios, and is suitable for charging wearable devices, such as charging an earphone case. Furthermore, it can also be applied to the aforementioned scenario of charging a mobile phone. In this case, Q11 is not required, meaning Q11 can be removed and Q10 can be included. When Q11 is included, it can be controlled to be always on, meaning it does not participate in power conversion. The first output terminal of the charging circuit provided in this embodiment is Vout2, and the second output terminal is Vout3.

[0184] like Figure 25B As shown, the two additional switches in this embodiment are the tenth switch Q10 and the eleventh switch Q11. Q10 and Q11 are required in the earphone box charging scenario. Moreover, in the earphone box charging scenario, the BuckBoost function can be realized. When the charging circuit provided in this embodiment operates in path four + 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:

[0185]

[0186] It can realize both forward closed-loop buck mode and closed-loop boost mode. Figure 26 , the figure is Figure 25B Schematic diagram of a corresponding working mode. Figure 26 Correspondingly, the controller controls the path diagram of Q1 and Q3 to be turned on and Q2 and Q4 to be turned off, wherein Q10 operates synchronously with Q3 and Q11 operates synchronously with Q4.

[0187] See also Figure 27 , the figure is Figure 25B Schematic diagram of another corresponding working mode. Figure 27 Correspondingly, the controller controls the path diagram of Q1 and Q3 being turned off and Q2 and Q4 being turned on, wherein Q10 operates synchronously with Q3 and Q11 operates synchronously with Q4.

[0188] The charging circuit provided in this embodiment can also operate in Path 5 + Control Strategy 1:

[0189] Vout2-Vout3, this path has the same control strategy as above; the topology is a variant BuckBoost structure, and the gain is:

[0190]

[0191] It can realize both forward closed-loop buck mode and closed-loop boost mode. For example, when the application scenario is an earphone box, when the earphone box is charging the earphones, the corresponding output power from Vout2 to Vout3 is as follows. Figure 28 As shown, this figure is a path diagram when Vbus is not connected to the power supply corresponding to Figure 25. At this time, Vbus is not connected to the external power supply, that is, the adapter is not connected to the headphone box. Figure 28 The corresponding control strategy and Figure 26 The control strategy is basically the same, except that the RBFET switch tube in this figure is kept off. The other control strategies are the same, that is, the controller controls Q1 and Q3 to be turned on, Q2 and Q4 to be turned off, among which Q10 and Q3 act synchronously, and Q11 and Q4 act synchronously; when Q1 and Q3 are both turned off, the path when Q2 and Q4 are both turned on is the same as Figure 27 Basically the same, the difference is that the RBFET switch tube must remain off.

[0192] In addition, the above control strategy can be further simplified to improve power conversion efficiency. For example, when the output voltage of Vout3 is lower than that of Vout2, the charging circuit provided in this embodiment can operate in a variant Buck mode. At this time, based on control strategy 1, Q10 is controlled to be normally off and Q11 is controlled to be normally on; the gain is:

[0193]

[0194] At this time, the charging circuit can realize the forward closed-loop buck mode. The mode when the controller controls Q1 and Q3 to turn on is as follows: Figure 29 As shown, the modal diagram when the controller controls Q1 and Q3 to turn off is as follows Figure 30 As shown. Figure 29 and Figure 30 It can be seen that Q10 is always off and Q11 is always on.

[0195] In addition, when the output voltage of Vout3 is higher than that of Vout2, the charging circuit provided in this embodiment can operate in the traditional Boost mode. In this case, Q1, Q2, and Q4 are controlled to be normally off, Q3 is normally on, and Q10 and Q11 are controlled to be alternately turned on. The duty cycle of Q10 is D, and the gain is:

[0196]

[0197] At this time, the charging circuit can realize the closed-loop boost working mode. Figure 31 and Figure 32 ,in Figure 31 Schematic diagram of Q11 being turned off and Q10 being turned on. Figure 32 The diagram in the figure shows Q11 on and Q10 off. The current path here can be seen in the direction of current iL. At most, only one of the RBFET and Q9 can be on at a time. In mobile phone fast charging scenarios, Q11 is not required. If Q11 is present, it can be kept on continuously.

[0198] When the phone's fast charger operates in an open-loop fast charging state, or the open-loop charging phase, RBFET is on and Q9 is off, operating in the forward direction of Path 2. When the phone's fast charger operates in a closed-loop charging phase, or when a 5V adapter is plugged in for charging, RBFET is off and Q9 replaces Q11, operating in the same manner as Path 5 + Control Strategy 1 in the figure above, or in reverse BuckBoost mode. The simplified control strategy for improving power conversion efficiency also applies to the closed-loop charging phase of the phone and will not be detailed here.

[0199] In the earphone box fast charging scenario, Q11 is required. The earphones can be connected to Vout3, and the earphone box battery is connected to Vout2. Vbus is connected to the adapter's open-loop charging phase, i.e., the open-loop fast charging phase, supporting SC voltage regulation, and simultaneously fast-charging the earphones and the earphone box; RBFET is turned on, Q9 is turned off, and the same path 2 and path 4 + control strategy 1 as described above operate in forward operation simultaneously; Vbus = 5V is inserted or the earphone box charging enters the closed-loop charging phase (configuration Vbus = 5V), RBFET is turned off, Q9 is turned on, Vbus = 5V directly charges the earphones, and the earphone box charging follows the path 5 + control strategy 1 described above. At this time, the charging circuit operates in reverse BuckBoost mode; in addition, the corresponding simplified control strategy for improving power conversion efficiency is also applicable and will not be repeated here.

[0200] When Vbus is disconnected from an external power source (i.e., when the adapter is not in place), the headphone case's battery charges the earphones. Following Path 5 + Control Strategy 1 described above, the charging circuit operates in forward BuckBoost mode. The simplified control strategy for improving power conversion efficiency also applies when the headphone case is charging the earphones, and will not be detailed here.

[0201] The charging circuit provided in this embodiment has the advantages of the charging circuit embodiments 2 to 4, and can operate in both open-loop charging mode and closed-loop charging mode, and can operate in both buck charging mode and boost charging mode. In addition, the second output terminal is connected to the power supply terminal through a 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 the intermediate power conversion link, thereby reducing power consumption and improving charging efficiency. Because the charging circuit can operate in reverse boost mode, it can be applied to multi-battery series scenarios of mobile terminals such as mobile phones, such as charging scenarios when two batteries are connected in series, so that it can be compatible with different adapters to meet the charging needs of different mobile terminals and wearable devices. In addition, the charging circuit provided in this embodiment also has the following advantages, that is, the charging circuit can operate in a boost mode and a buck mode. For example, in a scenario where an earphone box charges an earphone, the earphone box can either boost the voltage of its own battery to charge the earphone or step down the voltage of its own battery to charge the earphone. The earphone box can be flexibly controlled according to the different power levels of the battery to charge the earphone.

[0202] The above charging circuit embodiments 2 to 5 are all applicable to charging mobile terminals and wearable devices. The charging circuit provided in the present application is not like Figure 1The shown circuit includes two parallel open-loop charging circuits and closed-loop charging circuits, but organically integrates the open-loop charging circuit and the closed-loop charging circuit. The controller can realize different charging paths by controlling the different working modes of the switch tube. When open-loop charging is required, the high efficiency of open-loop charging can be used to achieve fast charging. When closed-loop charging is required, the working stability of the closed loop can be used to achieve stable fast charging. Moreover, some of the above charging circuits are also suitable for boost charging, which can be compatible with scenarios where the input voltage of the adapter is low, or compatible with scenarios where the charged electronic device includes two batteries connected in series. Therefore, the charging circuit provided in 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.

[0203] The types of the various switching tubes in the charging circuit provided in the above embodiments of the present application are not specifically limited. For example, they may be implemented by MOS tubes, or by triodes or transistors. For example, Q1-Q4 may be NMOS tubes.

[0204] Based on the above charging circuit embodiments 2 to 5, the present application also provides an electronic device, which is described in detail below with reference to the accompanying drawings.

[0205] Electronic device embodiment 2:

[0206] The present application also provides an electronic device, comprising: a battery and a charging circuit provided by any one of the above charging circuit embodiments 2 to 5. Figure 33 , this figure is a schematic diagram of another electronic device provided in 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, not shown in the figure; the second output end Vout1 or Vout3 of the charging circuit 100A is used to connect to the load of the first electronic device. It should be noted that the load of the first electronic device can be a power circuit or a second electronic device; for example, for the application scenario of a mobile phone, the first electronic device is a mobile phone, the battery of the first electronic device is the battery of the mobile phone, and the load of the first electronic device can be the power circuit inside the mobile phone. For the 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.

[0207] The charging circuit 100A is used to convert the electric energy provided by the power supply terminal Vbus to charge the battery and supply power to the load of the electronic device. Figure 33The 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 taken as an example of another battery with smaller capacity. For example, for the application scenario of the earphone box, the load of the earphone box is the earphone battery, that is, 300A.

[0208] The electronic device provided in the embodiment of the present application has a charging circuit including two output terminals, which can realize two charging paths, respectively, to quickly charge two different charged batteries or charged loads. Since the charging circuit included in the electronic device can operate in both open-loop charging mode and closed-loop charging mode, and can operate in both buck charging mode and boost charging mode. In addition, the second output terminal is connected to the power supply terminal through a 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 the intermediate power conversion link, thereby reducing power consumption and improving charging efficiency. Since the charging circuit can operate in 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 charging scenarios when two batteries are connected in series, so that it can be compatible with different adapters to meet the charging needs of different mobile terminals and wearable devices.

[0209] It should be understood that in this application, "at least one (item)" means one or more, and "plurality" means two or more. "And / or" is used to describe the association relationship of associated objects, indicating that three relationships may exist. For example, "A and / or B" can mean: only A exists, only B exists, and A and B exist at the same time, where A and B can be singular or plural. The character " / " generally indicates that the previous and next associated objects are in an "or" relationship. "At least one of the following items" or similar expressions refers to any combination of these items, including any combination of single items or plural items. For example, at least one 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.

[0210] As described above, the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A charging circuit, characterized in that: include: A first switching tube, a second switching tube, a third switching tube, a fourth switching 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 end, the second end of the first switch tube is connected to the first end of the second switch tube, 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, and the second end of the fourth switch tube is grounded; Two ends of the first capacitor are connected to the second end of the first switch tube and the second end of the third switch tube respectively; 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 a battery of the electronic device; The charging circuit further includes a sixth switch tube, wherein a first end of the sixth switch tube is connected to the second end of the third switch tube, and a second end of the sixth switch tube is connected to the second end of the first inductor.

2. The charging circuit according to claim 1, wherein: When the charging circuit includes the sixth switch tube, the charging circuit further includes: a backflow prevention switch tube and a charge and discharge control switch tube; The first end of the first switch tube is connected to the power supply end through the backflow prevention switch tube; The second end of the first inductor is connected to the battery through the charge and discharge control switch tube; The second end of the first inductor is connected to a system power supply end of the electronic device.

3. The charging circuit according to claim 2, wherein: The charging circuit further includes: 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 tube and the fourth switch tube to operate synchronously, when the battery is charged by reducing the voltage at the power supply end, and the first switch tube and the second switch tube to operate in opposite directions.

4. The charging circuit according to claim 2 or 3, characterized in that: The charging circuit further includes: a controller; The controller is further configured to control the second switch tube and the third switch tube to be disconnected when charging the battery after the power supply end is boosted, control the first switch tube and the fourth switch tube to operate synchronously, and control the first switch tube and the sixth switch tube to operate in opposite directions.

5. An electronic device, characterized in that: include: A battery and a charging circuit according to any one of claims 1 to 4; The first end of the charging circuit is used to connect to the power supply end, and the second end of the charging circuit is connected to the power supply end of the battery; The charging circuit is used to convert the electric energy provided by the power supply end into the electric energy for charging the battery.

6. A charging circuit, characterized in that: include: A first switching tube, a second switching tube, a third switching tube, a fourth switching tube, a first capacitor and a first inductor; The first end of the first switch tube is used to connect to the power supply end, the second end of the first switch tube is connected to the first end of the second switch tube, 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, and the second end of the fourth switch tube is grounded; Two ends of the first capacitor are connected to the second end of the first switch tube and the second end of the third switch tube respectively; The second end of the second switch tube serves as a first output end, and is used to charge a 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 second end of the first inductor serves as a second output end to supply power to a load of the first electronic device; The charging circuit further includes: an eighth switching tube or a ninth switching tube, wherein a first end of the eighth switching tube is used to connect to the power supply terminal, and a second end of the eighth switching tube is connected to the second output terminal; and a second end of the first inductor is connected to the power supply terminal via the ninth switching tube; When the load of the first electronic device is a second electronic device, the second output end is used to charge the second electronic device. When the voltage of the battery is boosted to charge the second electronic device, the second switch tube and the fourth switch tube operate synchronously, and the second switch tube and the third switch tube operate in opposite directions.

7. The charging circuit according to claim 6, wherein: The charging circuit further includes: 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 tube and the fourth switch tube to operate synchronously, when the power supply end is used to perform open-loop charging for the battery. The first switch tube and the second switch tube operate in opposite directions.

8. The charging circuit according to claim 6, wherein: The charging circuit further includes: a controller and a fifth switch tube, wherein a first end of the fifth switch tube is connected to the second end of the first inductor, and a second end of the fifth switch tube is connected to the first output end; The controller is further configured to, during the closed-loop charging phase, control the second switch tube to be disconnected, control the fifth switch tube to be closed, control the first switch tube and the third switch tube to operate synchronously, and control the first switch tube and the fourth switch tube to operate in opposite directions.

9. The charging circuit according to claim 6, characterized in that: The charging circuit further includes: a controller and a fifth switch tube, wherein a first end of the fifth switch tube is connected to the second end of the first inductor, and a second end of the fifth switch tube is connected to the first output end; The controller is further configured to, during the closed-loop charging phase, control the second switch tube to be disconnected, control the fifth switch tube to be closed, control the first switch tube and the fourth switch tube to operate synchronously, and control the first switch tube and the third switch tube to operate in opposite directions.

10. The charging circuit according to claim 8 or 9, characterized in that: The controller is further configured to control the second switch tube to operate synchronously with the fourth switch tube, and to control the second switch tube to operate in the opposite direction to the third switch tube, when the battery voltage is boosted to charge the second electronic device.

11. The charging circuit according to claim 6, wherein: The second end of the first switch tube is connected to the first end of the first inductor; When the charging circuit includes the eighth switch tube, the charging circuit further includes: a backflow prevention switch tube; The first end of the first switch tube is connected to the power supply end through the backflow prevention switch tube.

12. The charging circuit according to claim 11, wherein: Also includes: Controller; The controller is used to control the anti-backflow switch tube to be turned on and the eighth switch tube to be turned off during the open-loop charging stage; and to control the eighth switch tube to be turned on and the anti-backflow switch tube to be turned off during the closed-loop charging stage.

13. The charging circuit according to claim 12, wherein: 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 to operate synchronously during the open-loop charging stage, wherein the first switch tube and the second switch tube operate in opposite directions.

14. The charging circuit according to claim 12, wherein: The controller is further configured to control the second switch tube and the fourth switch tube to operate synchronously, and control the second switch tube and the third switch tube to operate in opposite directions during the closed-loop charging stage.

15. The charging circuit according to any one of claims 12 to 14, characterized in that: The controller is further configured to control the second switch tube to operate synchronously with the fourth switch tube, and to control the second switch tube to operate in the opposite direction to the third switch tube, when the battery is used to charge the second electronic device.

16. The charging circuit according to claim 6, wherein: The second end of the third switch tube is connected to the first end of the first inductor; When the charging circuit includes the ninth switch tube, the charging circuit further includes: a backflow prevention switch tube; The first end of the first switch tube is used to connect to the power supply end through the backflow prevention switch tube.

17. The charging circuit according to claim 16, wherein: Also includes: Controller; The controller is configured to control the backflow prevention switch to be turned on and the ninth switch to be turned off during the open-loop charging phase; During the closed-loop charging phase, the ninth switch tube is controlled to be turned on or periodically turned on, and the backflow prevention switch tube is controlled to be turned off.

18. The charging circuit according to claim 17, wherein: 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 to operate synchronously during the open-loop charging stage, wherein the first switch tube and the second switch tube operate in opposite directions.

19. The charging circuit according to claim 17, wherein: The controller is further configured to 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 and the second switch tube to operate in opposite directions during the closed-loop charging stage.

20. The charging circuit according to any one of claims 17 to 19, characterized in that: The controller is further configured to 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 and the second switch tube to operate in opposite directions when the battery is used to charge the second electronic device.

21. The charging circuit according to claim 17, wherein: Also includes: tenth switch tube; A first end of the tenth switch tube is connected to the second end of the first inductor, and a second end of the tenth switch tube is grounded.

22. The charging circuit according to claim 21, characterized in that The controller is further configured to control the ninth switch tube to be periodically turned on, control the ninth switch tube and the tenth switch tube to be alternately turned on, control the fourth switch tube to be turned off, and control the third switch tube to be turned on during the closed-loop buck charging phase.

23. The charging circuit according to claim 21, characterized in that: The controller is further configured to control the periodic conduction of the ninth switch tube, control the synchronous operation of the first switch tube, the third switch tube, and the tenth switch tube, and control the synchronous operation of the second switch tube, the fourth switch tube, and the ninth switch tube during the closed-loop buck-boost charging phase.

24. The charging circuit according to any one of claims 21 to 23, characterized in that: Also includes: 11th switch tube; 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 serves as the second output end; the controller is further used to control the eleventh switch tube to operate synchronously with the fourth switch tube.

25. The charging circuit according to claim 24, characterized in that The controller is further configured to control the first switching tube and the third switching tube to operate synchronously, control the second switching tube and the fourth switching tube to operate synchronously, the first switching tube and the second switching tube to operate in opposite directions, control the tenth switching tube and the third switching tube to operate synchronously, and control the eleventh switching tube and the fourth switching tube to operate synchronously.

26. The charging circuit according to claim 24, wherein: The controller is further configured to, when the voltage at the second output terminal is less than the voltage at the first output terminal, control the tenth switch tube to turn off and control the eleventh switch tube to turn 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 and the second switch tube to operate in opposite directions.

27. The charging circuit according to claim 24, wherein: The controller is further configured to control the first, second, and fourth switching tubes to be turned off, control the third switching tube to be turned on, and control the tenth and eleventh switching tubes to be turned on alternately when the voltage at the second output terminal is greater than the voltage at the first output terminal.

28. An electronic device, characterized in that: include: A battery and a charging circuit according to any one of claims 6 to 27; The first end of the charging circuit is used to connect to the power supply end, and 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 to the load of the electronic device; The charging circuit is used to convert the electric energy provided by the power supply end into the electric energy for charging the battery and supplying power to the load of the electronic device.

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