Charging circuit, method, system, battery and electronic device

Abstract

The present application discloses a charging circuit, which is applied to an electronic device. The charging circuit includes a first conversion circuit, a transformer, and a second conversion circuit, which are cascaded in sequence, and a control circuit for connecting a charger outside the electronic device and a battery cell of the electronic device. The control circuit is used to adjust the voltage of the direct current provided by the charger to N times the voltage of the battery cell based on the voltage of the battery cell, where N is greater than or equal to 2; the current provided by the charger is input into the first conversion circuit, and output to the battery cell via the transformer and the second conversion circuit. By setting the transformer, a higher voltage transformation ratio can be achieved, thereby reducing the channel current between the first conversion circuit and the transformer, so as to reduce the channel impedance between the first conversion circuit and the transformer, thereby reducing the loss of charging power and reducing the temperature rise. The present application also discloses a charging system and method, as well as a battery and an electronic device.

Description

Technical Field

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

[0002] Battery charging is becoming more and more important in current electronic devices such as mobile phones and tablets. Due to the continuous increase in battery capacity and the growing demand of users for shorter charging time, the demand for fast charging of electronic devices is also gradually increasing. Therefore, fast and efficient charging solutions are the main trends.

[0003] Currently, in the fast charging scheme used by the aforementioned electronic devices, using a switched capacitor circuit to increase the charging current during the constant current charging stage of the battery is a major solution. However, due to the limitations of the switched capacitor circuit, it cannot support a higher voltage transformation ratio, and thus cannot achieve a greater current increase. Furthermore, there are also problems of large temperature rise and efficiency loss. Summary of the invention

[0004] The present application provides a charging circuit, method, system, battery and electronic device, which can achieve a higher voltage transformation ratio to achieve a greater current increase, reduce efficiency loss and lower temperature rise.

[0005] To solve the above technical problems, in the first aspect, an embodiment of the present application provides a charging circuit, which is applied to an electronic device, and the charging circuit is used to connect to a charger outside the electronic device and a battery cell of the electronic device respectively. The charging circuit includes a first conversion circuit, a transformer, and a second conversion circuit that are cascaded in sequence. The current provided by the charger is input into the first conversion circuit, and is provided to the battery cell via the transformer and the second conversion circuit; the charging circuit also includes a control circuit, and the control circuit is used to connect to the charger and the battery cell respectively; and the control circuit is used to adjust the voltage of the direct current provided by the charger to N times the voltage of the battery cell based on the voltage of the battery cell, where N is greater than or equal to 2; the first conversion circuit is used to convert the direct current transmitted by the charger into alternating current, and output it to the transformer; the transformer is used to step down the voltage of the alternating current transmitted by the first conversion circuit to 1 / N of the voltage of the alternating current transmitted by the first conversion circuit, and output it to the second conversion circuit; the second conversion circuit is used to convert the alternating current transmitted by the transformer into direct current, and output it to the battery cell. By setting the transformer, a higher voltage transformation ratio can be achieved, and a greater current increase can be achieved. Furthermore, the channel current between the first conversion circuit and the transformer can be reduced to reduce the channel impedance between the first conversion circuit and the transformer, thereby reducing the loss of charging power and reducing the temperature rise.

[0006] In a possible implementation of the first aspect above, N may be a voltage transformation ratio of the transformer, and may be a positive integer greater than or equal to 2.

[0007] In a possible implementation of the first aspect above, the control circuit is used to generate instruction information based on the voltage of the battery cell and send it to the charger, so that the charger adjusts the voltage of the DC power provided by the charger to N times the voltage of the battery cell according to the instruction information.

[0008] In a possible implementation of the first aspect above, the first conversion circuit includes a DC to AC circuit, and the second conversion circuit includes an AC to DC circuit.

[0009] In a possible implementation of the first aspect above, the DC to AC circuit is a full-bridge rectifier circuit for converting DC power into AC power.

[0010] In a possible implementation of the first aspect, the first conversion circuit further includes an inductor connected to the DC-to-AC circuit and the transformer, respectively, and the second conversion circuit further includes a capacitor connected to the AC-to-DC circuit and the transformer, respectively, and the inductor and the capacitor form an LC resonant circuit. The LC resonant circuit can quickly increase the current at the initial stage of circuit conduction, thereby further improving the conversion efficiency of the transformer.

[0011] In a possible implementation of the first aspect above, the control circuit is used to detect the positive and negative electrode voltages of the battery cell to obtain the voltage of the battery cell.

[0012] In a possible implementation of the first aspect above, the control circuit is also used to connect to the first conversion circuit and the second conversion circuit respectively; the control circuit is also used to control the first conversion circuit to convert direct current into alternating current, and to control the second conversion circuit to convert alternating current into direct current.

[0013] In a possible implementation of the first aspect above, the control circuit is used to send a first control signal to the first conversion circuit and to send a second control signal to the second conversion circuit; the first conversion circuit is used to convert direct current into alternating current according to the first control signal; and the second conversion circuit is used to convert alternating current into direct current according to the second control signal.

[0014] In a possible implementation of the first aspect above, when the battery cell is charged with a constant current, the control circuit is used to adjust the voltage of the direct current provided by the charger to N times the voltage of the battery cell based on the voltage of the battery cell.

[0015] In a possible implementation of the first aspect above, the charging circuit is used to connect to a charger via a Universal Serial Bus (USB).

[0016] In a second aspect, an embodiment of the present application provides an electronic device, which includes a battery cell and the aforementioned charging circuit.

[0017] In a possible implementation of the second aspect, the electronic device further includes a battery protection board, and the transformer and the second conversion circuit are disposed on the battery protection board. The transformer is disposed on the battery protection board, which reduces the distance between the transformer and the battery cell. Since there is a large current channel between the voltage regulator and the battery cell, the channel impedance between the voltage regulator and the battery cell can be reduced, thereby reducing power loss and lowering temperature rise.

[0018] In a possible implementation of the second aspect above, the electronic device further includes a device mainboard, and the control circuit and the first conversion circuit are arranged on the device mainboard.

[0019] The electronic device provided in the present application includes the charging circuit provided by the above-mentioned first aspect and / or any possible implementation method of the first aspect, and thus can also achieve the beneficial effects (or advantages) of the charging circuit provided by the first aspect.

[0020] In a third aspect, an embodiment of the present application provides a charging system, which includes: a charger and an electronic device connected to each other, the electronic device being the aforementioned electronic device; wherein the electronic device is used to generate indication information according to the voltage of a battery cell in the electronic device, and send the indication information to the charger; the charger is used to adjust the voltage of the DC power provided by the charger to N times the voltage of the battery cell according to the indication information, wherein N is greater than or equal to 2; the electronic device is also used to convert the DC power transmitted by the charger into AC power, and to step down the voltage of the AC power to 1 / N of the voltage of the DC power transmitted by the charger, and to convert the stepped-down AC power into DC power, and output it to the battery cell.

[0021] In a possible implementation of the third aspect, the charger and the electronic device may be connected to each other via a connecting wire for charging, or may be connected to each other wirelessly for charging.

[0022] The charging system provided in the present application includes the electronic device provided by the above-mentioned second aspect and / or any possible implementation method of the second aspect, and thus can also achieve the beneficial effects (or advantages) of the charging circuit provided by the second aspect.

[0023] In a fourth aspect, an embodiment of the present application provides a charging method, which is applied to a charger and an electronic device connected to each other, wherein the electronic device is the aforementioned electronic device; the charging method includes: the electronic device generates indication information according to the voltage of the battery cell in the electronic device, and sends the indication information to the charger; the charger adjusts the voltage of the direct current power output by the charger to N times the voltage of the battery cell according to the indication information, wherein N is greater than or equal to 2; the electronic device converts the direct current power transmitted by the charger into alternating current power, and steps down the voltage of the alternating current power transmitted by the charger to 1 / N of the voltage of the direct current power transmitted by the charger, and converts the stepped-down alternating current power into direct current power, and outputs it to the battery cell.

[0024] The charging method provided in the present application is applied to the charging system provided by the above-mentioned third aspect and / or any possible implementation method of the third aspect, and thus can also achieve the beneficial effects (or advantages) of the charging system provided by the third aspect.

[0025] In a fifth aspect, an embodiment of the present application provides a battery, comprising a battery cell, the battery cell comprising a first pole and a second pole; a battery protection board, the battery protection board comprising a transformer and a conversion circuit connected to each other, and the conversion circuit is respectively connected to the first pole and the second pole; wherein the transformer is used to step down the voltage of the received alternating current to 1 / N of the voltage of the received alternating current, and output it to the conversion circuit; the conversion circuit is used to convert the alternating current transmitted by the transformer into direct current, and output it to the battery cell.

[0026] In a possible implementation of the fifth aspect above, the battery further includes a packaging shell, and the battery cells and the battery protection board are arranged in the packaging shell.

[0027] The battery provided in the present application can achieve a higher voltage transformation ratio and a greater current increase through the setting of a transformer. Furthermore, since the distance between the battery protection board and the battery cell is small, the transformer is set on the battery protection board, that is, the transformer is placed close to the battery cell, so that the distance between the transformer and the battery cell is reduced. Since the current between the transformer and the battery cell is large, the distance between the transformer and the battery cell is reduced, that is, the large current path is effectively reduced, and the channel impedance between the transformer and the battery cell can be effectively reduced, thereby effectively reducing the loss of charging power and reducing the temperature rise. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings used in the description of the embodiments are briefly introduced below.

[0029] Figure 1 is a schematic diagram showing a charging system according to some embodiments of the present application;

[0030] Figure 2is a structural block diagram showing a charging circuit in a charging system according to some embodiments of the present application;

[0031] Figure 3 is a structural block diagram showing a charging circuit in another charging system according to some embodiments of the present application;

[0032] Figure 4 is a schematic diagram showing a structure of a charging circuit in another charging system according to some embodiments of the present application;

[0033] Figure 5A According to some embodiments of the present application, a current waveform diagram of the alternating current input to the transformer by a first conversion circuit is shown;

[0034] Figure 5B According to some embodiments of the present application, a voltage waveform diagram of the alternating current input to the transformer by a first conversion circuit is shown;

[0035] Figure 5C According to some embodiments of the present application, a current waveform diagram of direct current input from a charger to a first conversion circuit, and a current waveform diagram of direct current input from a second conversion circuit to a battery cell are shown;

[0036] Figure 5D According to some embodiments of the present application, a voltage waveform diagram of direct current input from a charger to a first conversion circuit, and a voltage waveform diagram of direct current input from a second conversion circuit to a battery cell are shown;

[0037] Figure 6 is a schematic diagram showing the structure of a battery according to some embodiments of the present application;

[0038] Figure 7 is a schematic diagram showing the structure of another battery according to some embodiments of the present application;

[0039] Figure 8 A schematic flow chart of a charging method is shown according to some embodiments of the present application.

[0040] Reference numerals:

[0041] 100: mobile phone; 200: charger; 300: connecting line; 310: first connecting line; 320: second connecting line; 110: charging circuit; 111: first conversion circuit; 112: transformer; 113: second conversion circuit; 114: control circuit; 120: battery cell; 121: first pole; 122: second pole; 130: device main board; 140: battery protection board; 141: first output terminal; 142 second output terminal; 150: battery; M1: first MOS tube; M2: second MOS tube; M3: third MOS tube; M4: fourth MOS tube; M5: fifth MOS tube; M6: sixth MOS tube; L: inductor; C1: first capacitor; C2: second capacitor; N: junction field effect tube. DETAILED DESCRIPTION

[0042] The following specific embodiments illustrate the implementation of the present application, and those skilled in the art can easily understand other advantages and effects of the present application from the contents disclosed in this specification. Although the description of the present application will be introduced in conjunction with the embodiments, this does not mean that the features of this application are limited to the implementation. On the contrary, the purpose of introducing the application in conjunction with the implementation is to cover other options or modifications that may be extended based on the claims of the present application. In order to provide a deep understanding of the present application, the following description will include many specific details. The present application can also be implemented without using these details. In addition, in order to avoid confusion or blurring the focus of the present application, some specific details will be omitted in the description. It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict.

[0043] It should be noted that in this specification, similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings.

[0044] In order to make the objectives, technical solutions and advantages of the present application clearer, the implementation methods of the present application will be further described in detail below in conjunction with the accompanying drawings.

[0045] It should be noted that in the fast charging scheme currently used by the charging circuit, the use of a switched capacitor circuit to increase the charging current is a major solution during the constant current charging stage of the battery. For example, in one implementation of the fast charging scheme, the charging system includes a charger and a charging circuit, wherein the charger is connected to the charging circuit via a USB, the charging circuit includes a device mainboard and a battery protection board, and the device mainboard and the battery protection board are connected via a battery connector and a flexible board. In addition, a charging IC is provided on the device mainboard, and the charging IC includes a switched capacitor circuit and a control circuit, wherein the switched capacitor circuit is used to realize the conversion from high voltage and low current to low voltage and high current, and the battery protection circuit is used to realize the protection of the battery from overcharging and over-discharging.

[0046] However, the switched capacitor circuit has limitations. When using the switched capacitor circuit to achieve voltage reduction, the first-stage switched capacitor can only achieve a voltage reduction ratio of 2:1, which cannot support a higher voltage reduction ratio. Furthermore, in order to achieve a larger voltage reduction ratio, the switched capacitors need to be cascaded. However, the cascaded switched capacitors will result in efficiency loss. For example, the efficiency of the first-stage switched capacitor is 97%, and the efficiency becomes 97%*97%=94% after the two-stage series connection. If a higher voltage ratio needs to be achieved, it will further result in efficiency loss, making it impossible to achieve a larger current increase.

[0047] In addition, the power loss in the charging circuit is related to the charging circuit structure. The power loss P = I 2 ×R, where I is the charging current in the charging circuit, and R is the channel impedance in the charging circuit. R is generally affected by the product structure, and R of a specific product is a fixed value. When R is fixed, the larger the charging current I, the greater the power loss P, and thus the greater the efficiency loss and temperature rise. The battery connector plus a flexible board is generally used to connect the device motherboard to the battery protection board. Therefore, the current from the device motherboard to the battery protection board is large, which will cause a large power loss from the device motherboard to the battery protection board, that is, it will cause a large efficiency loss and temperature rise.

[0048] To solve the aforementioned problems, the present application provides a charging system, which includes an electronic device and a charger for charging the electronic device, wherein the electronic device includes but is not limited to mobile phones, tablet computers, televisions, laptop computers, ultra-mobile personal computers (UMPCs), handheld computers, netbooks, personal digital assistants (PDAs), wearable devices, virtual reality devices and other electronic devices.

[0049] See also Figure 1 In one implementation of the present application, the charging system includes a mobile phone 100 and a charger 200. The mobile phone 100 and the charger 200 are connected via a connecting line 300 in a USB connection manner. The charger converts AC power to DC power and outputs the converted DC power to the mobile phone 100 via the connecting line 300 to charge the mobile phone 100.

[0050] It should be noted that the connecting line 300 has a current transmission function to realize current transmission between the charger 200 and the mobile phone 100 , and has a communication function to realize information transmission between the charger 200 and the mobile phone 100 .

[0051] Of course, the mobile phone 100 and the charger 200 may also be charged and communicated directly in a wireless manner.

[0052] See also Figure 2 The mobile phone 100 includes a charging circuit 110 and a battery cell 120. The charging circuit 110 is used to perform constant current charging on the battery cell 120. In addition, the charging circuit 110 includes a first conversion circuit 111, a transformer 112, and a second conversion circuit 113 which are cascaded in sequence. The current provided by the charger 200 is input to the first conversion circuit 111, and is output to the battery cell 120 via the transformer 112 and the second conversion circuit 113. The charging circuit 110 also includes a control circuit 114, which is connected to the charger 200 and the battery cell 120, respectively.

[0053] The control circuit 114 is used to adjust the voltage provided by the charger 200 to N times the voltage output by the battery cell 120 based on the voltage output by the battery cell 120, that is, the control circuit 114 can detect the voltage between the positive and negative poles of the battery cell 120 in real time or regularly to obtain the voltage output by the battery cell 120, and then dynamically adjust the output voltage of the charger 200 according to the detected voltage between the positive and negative poles of the battery cell 120. For example, if the voltage between the positive and negative poles of the battery cell 120 is detected to be V1, the control circuit 114 adjusts the voltage V2 output by the charger 200 to V2=N×V1. It should be noted that N is determined according to the voltage transformation ratio of the transformer, that is, N can be the voltage transformation ratio of the transformer, and N is greater than or equal to 2. For example, if V1 is 4.5V and N is 6, then V2 is 27V. In addition, the current output by the charger in this application can be 5A.

[0054] In addition, the control circuit 114 is used to adjust the voltage provided by the charger 200 to N times the voltage output by the battery cell 120 based on the voltage output by the battery cell 120. The control circuit 114 may generate indication information based on the voltage output by the battery cell 120 and send it to the charger, so that the charger dynamically adjusts the voltage provided by the charger 200 according to the indication information.

[0055] The indication information may include the positive and negative voltages of the battery cell 120 and the voltage transformation ratio N of the transformer 112, so that the charger 200 adjusts its output voltage to N times the positive and negative voltages of the battery cell 120 according to the positive and negative voltages of the battery cell 120 and the voltage transformation ratio N. In addition, the indication information may also be the voltage value determined by the mobile phone 100 that the charger 200 needs to output, so that the charger 200 adjusts its output voltage according to the voltage value, which can be selected as needed.

[0056] In addition, the charger 200 realizes the conversion from AC power to DC power, so the current output by the charger 200 is DC power.

[0057] In the present application, the control circuit 114 controls the output voltage of the charger 200 according to the output voltage of the battery cell 120, and adjusts the output voltage of the charger 200 to N times the voltage output by the battery cell 120, which can effectively reduce the current between the charger 200 and the first conversion circuit 111, thereby effectively reducing the channel impedance between the charger 200 and the first conversion circuit 111, so as to reduce power loss and reduce temperature rise.

[0058] The transformer 112 may be an AC transformer, and the first conversion circuit 111 is used to convert the DC power transmitted from the charger 200 into AC power and output the AC power to the transformer 112 .

[0059] The transformer 112 is used to step down the voltage of the AC power transmitted by the first conversion circuit 111 to 1 / N of the voltage of the AC power transmitted by the first conversion circuit 111, and output it to the second conversion circuit 113. For example, the voltage of the DC power transmitted by the first conversion circuit 111 is V3, and the voltage output by the transformer 112 is V4, then V4 = V3 / N. For example, if V3 = 27V, then V4 = 4.5V.

[0060] It should be noted that the transformer 112 is used to realize the conversion from high voltage and low current to low voltage and high current. Therefore, the transformer 112 reduces the voltage of the AC power transmitted by the first conversion circuit 111 to 1 / N of the voltage of the AC power transmitted by the first conversion circuit 111, and adjusts the current of the AC power transmitted by the first conversion circuit 111 to N times the current of the AC power transmitted by the first conversion circuit 111, thereby effectively increasing the current input to the battery cell 120 and improving the charging efficiency. For example, the current of the AC power output by the transformer 112 can be 6 times the aforementioned 5A, that is, 30A.

[0061] The second conversion circuit 113 is used to convert the alternating current transmitted by the transformer 112 into direct current, and output the direct current to the battery cell 120 for charging the battery cell 120 .

[0062] Furthermore, the control circuit 114 is connected to the first conversion circuit 111 and the second conversion circuit 113 respectively, and the control circuit 114 is also used to control the current adjustment of the first conversion circuit 111 and the second conversion circuit 113, so as to control the first conversion circuit 111 to convert direct current into alternating current, and control the second conversion circuit 113 to convert alternating current into direct current.

[0063] The transformer 112 in the present application may be an AC transformer based on magnetic materials, whose step-down efficiency is not limited by the step-down ratio and can achieve a larger step-down ratio with high efficiency.

[0064] The charging circuit provided in the present application uses a transformer 112 to step down the voltage. Compared with a capacitor switching circuit, when performing constant current charging, it can support a higher voltage transformation ratio (step-down ratio), thereby overcoming the problem that a single switching capacitor circuit cannot achieve a large voltage transformation ratio. Compared with the switching capacitor circuit, which has a large power loss problem, the setting of the transformer 112 can achieve a higher voltage transformation ratio and a greater current increase. Furthermore, it can also reduce the channel current between the first conversion circuit 111 and the transformer 112 to reduce the channel impedance between the first conversion circuit 111 and the transformer 112, thereby reducing the loss of charging power and reducing the temperature rise. In addition, a larger current can be achieved when charging the battery cell 120, thereby improving the charging rate, that is, improving the charging function of the battery cell 120 in the constant current charging stage.

[0065] Furthermore, as mentioned above, the switched capacitor circuit solution requires switched capacitors to be cascaded or combined to achieve different power ratios, and the switched capacitor circuit is relatively complex to implement. However, the charging circuit provided in the present application only needs to adjust the turns ratio of the transformer 112 to achieve the requirements of different voltage ratios for different charging scenarios. The circuit is simple and convenient to implement, and can effectively reduce the circuit volume, which meets the requirements of the mobile phone 100 for miniaturization of the charging circuit structure.

[0066] See also Figure 3 In the present application, the mobile phone 100 further includes a device mainboard 130 and a battery protection board 140 , wherein the aforementioned control circuit 114 and the first conversion circuit 111 are arranged on the device mainboard 130 . The transformer 112 and the second conversion circuit 113 are arranged on the battery protection board 140 .

[0067] The distance between the battery protection board 140 and the battery cell 120 is usually smaller than the distance between the device main board 130 and the battery cell 120, and the distance between the battery protection board 140 and the battery cell 120 is usually 1 mm to 5 mm, for example, it can be 1 mm, 1.5 mm, 2 mm, 3 mm, 3.5 mm, 5 mm, etc.

[0068] Therefore, the transformer 112 is arranged on the battery protection board 140, that is, the transformer 112 is placed close to the battery cell 120, so that the distance between the transformer 112 and the battery cell 120 is reduced. Since the current between the transformer 112 and the battery cell 120 is large, the distance between the transformer 112 and the battery cell 120 is reduced, that is, the large current path is effectively reduced, and the channel impedance between the transformer 112 and the battery cell 120 can be effectively reduced, thereby effectively reducing the temperature rise and power loss generated in the channel.

[0069] In addition, the charger 200 is connected to the mobile phone 100 via the connecting line 300 , and the charger 200 may be connected to the device mainboard 130 via the connecting line 300 .

[0070] Further, in the present application, the aforementioned control circuit 114 and the charger 200 may be connected by the control circuit 114 and the first conversion circuit 111, and the connection with the charger 200 is realized through the first conversion circuit 111, or the control circuit 114 is directly connected to the charger 200 through an electrical connection line. In addition, the control circuit 114 and the battery cell 120 may be connected by the control circuit 114 and the second conversion circuit 113, and the connection with the battery cell 120 is realized through the second conversion circuit 113, or the control circuit 114 is directly connected to the battery cell 120 through an electrical connection line. It can be selected and set as needed.

[0071] In the present application, the first conversion circuit 111 includes a DC to AC circuit, and the DC to AC circuit can be a full-bridge rectifier circuit for converting DC power into AC power. The second conversion circuit 113 includes an AC to DC circuit. Further, the first conversion circuit 111 also includes an inductor for forming an LC resonant circuit, and the second conversion circuit also includes a capacitor for forming an LC resonant circuit, wherein the inductor is connected to the DC to AC circuit and the transformer, respectively, and the capacitor is connected to the AC to DC circuit and the transformer 112, respectively.

[0072] like Figure 4 As shown, in one implementation of the present application, the DC-to-AC circuit is a full-bridge rectifier circuit, and the full-bridge rectifier circuit includes a first MOS tube M1, a second MOS tube M2, a third MOS tube M3 and a fourth MOS tube M4, and the connecting line 300 includes a first connecting line 310 and a second connecting line 320, wherein the source of the first MOS tube M1 and the drain of the second MOS tube M2 are connected, the drain of the first MOS tube M1 is connected to the first connecting line 310, the source of the second MOS tube M2 is connected to the second connecting line 320, the source of the third MOS tube M3 and the drain of the fourth MOS tube M4 are connected, the drain of the third MOS tube M3 is connected to the first connecting line 310, the source of the fourth MOS tube M4 is connected to the second connecting line 320, and the gates of the first MOS tube M1, the second MOS tube M2, the third MOS tube M3 and the fourth MOS tube M4 are connected to the control circuit 114 respectively.

[0073] The current provided by the charger 200 is output to the drains of the first MOS transistor M1 and the third MOS transistor M3 through the first connecting line 310, and is output to the sources of the second MOS transistor M2 and the fourth MOS transistor M4 through the second connecting line 320. The first control signal output by the control circuit 114 for controlling the switches of each MOS transistor is output to the first MOS transistor M1, the second MOS transistor M2, the third MOS transistor M3 and the fourth MOS transistor M4 through the gates of the first MOS transistor M1, the second MOS transistor M2, the third MOS transistor M3 and the fourth MOS transistor M4, respectively, so as to control the switches of the first MOS transistor M1, the second MOS transistor M2, the third MOS transistor M3 and the fourth MOS transistor M4, thereby converting the direct current provided by the charger 200 into alternating current.

[0074] The first conversion circuit 111 further includes an inductor L, a first end of the inductor L is connected to the source of the first MOS transistor M1 and the drain of the second MOS transistor M2 respectively, a second end of the inductor L is connected to one end of the primary of the transformer 112, and the other end of the primary of the transformer 112 is connected to the source of the third MOS transistor M3 and the drain of the fourth MOS transistor M4. Thus, the alternating current output by the first conversion circuit 111 is output to the transformer 112 through the inductor L and the source of the third MOS transistor M3 and the drain of the fourth MOS transistor M4.

[0075] like Figure 4 As shown, the second conversion circuit 113 includes an AC-DC circuit and a first capacitor C1, and the AC-DC circuit includes a fifth MOS transistor M5, a sixth MOS transistor M6, a junction field effect transistor N, and a second capacitor C2, wherein the source of the fifth MOS transistor M5 is connected to the source of the sixth MOS transistor M6, the drain of the fifth MOS transistor M5 is connected to the secondary first end of the transformer 112, and the gate of the fifth MOS transistor M5 and the gate of the sixth MOS transistor M6 are respectively connected to the control circuit 114, one end of the first capacitor C1 is connected to the secondary first end of the transformer, the other end of the first capacitor C1 is connected to the drain of the junction field effect transistor N, and the source of the junction field effect transistor N is connected to the secondary second end of the transformer 112, and the gate of the junction field effect transistor N is connected to the control circuit 114. The drain of the sixth MOS transistor M6 is connected to the secondary second end of the transformer 112. One end of the second capacitor C2 is connected to the secondary third end of the transformer 112 and the positive electrode of the battery cell 120 respectively, and the other end of the second capacitor C2 is connected to the source of the sixth MOS transistor M6 and the negative electrode of the battery cell 120 respectively.

[0076] The AC power output by the transformer 112 is respectively output to one end of the first capacitor C1, the gate of the fifth MOS transistor M5, one end of the second capacitor C2 and the source of the junction field effect transistor N through the secondary first end, the secondary second end and the secondary third end of the transformer 112. In addition, the control circuit 114 sends the second control signal used to control the switching of the fifth MOS transistor M5, the sixth MOS transistor M6 and the junction field effect transistor N to the gates of the fifth MOS transistor M5, the sixth MOS transistor M6 and the junction field effect transistor N, so as to control the switching of the fifth MOS transistor M5, the sixth MOS transistor M6 and the junction field effect transistor N, so that the fifth MOS transistor M5, the sixth MOS transistor M6 and the junction field effect transistor N cooperate with the switching cycle of the first MOS transistor M1, the second MOS transistor M2, the third MOS transistor M3 and the fourth MOS transistor M4 to convert the AC power transmitted by the transformer 112 into DC power.

[0077] It should be noted that, in the present application, the first MOS tube M1, the second MOS tube M2, the third MOS tube M3, the fourth MOS tube M4, the fifth MOS tube M5 and the sixth MOS tube M6 are all NMOS transistors (N-Metal-Oxide-Semiconductor, NMOS), and the junction field effect transistor N is an N-type junction field effect transistor.

[0078] like Figure 4 In the charging circuit shown, the aforementioned DC-to-AC circuit, under the control of the control circuit 114, converts the DC power transmitted from the charger 200 into AC power with a higher frequency. In addition, under the control of the control circuit 114, the AC-to-DC circuit converts the AC power transmitted from the transformer 112 into DC power to supply power to the battery cell 120.

[0079] The inductor L deployed in the first conversion circuit 111 and the first capacitor C1 deployed in the second conversion circuit can form an LC resonant circuit. The current passing through the inductor L and the first capacitor C1 forms an LC resonant current, which can quickly increase the current at the initial stage of circuit conduction, thereby further improving the conversion efficiency of the transformer 112.

[0080] Furthermore, through the aforementioned DC to AC circuit and LC resonant circuit, the current of the AC power with a higher frequency input from the first conversion circuit 111 to the transformer 112 can be made close to a square wave, thereby effectively reducing switching losses.

[0081] The current waveform of the alternating current input from the first conversion circuit 111 to the transformer 112 can be as follows: Figure 5A The waveform close to a square wave shown in FIG. 1 (where the horizontal axis of the coordinate axis is time t and the vertical axis is the current value I), the voltage waveform of the alternating current can be Figure 5BThe waveform shown (wherein the horizontal axis is time t and the vertical axis is voltage value V).

[0082] Further, in the present application, the current waveform of the direct current input from the charger 200 to the first conversion circuit 111 is as follows: Figure 5C The waveform I1 shown in FIG. 1 , wherein the current value can be the aforementioned 5A, and the voltage waveform of the DC power is as follows: Figure 5D The voltage value of V1 shown in the figure can be the aforementioned 27V.

[0083] The current waveform of the direct current input from the second conversion circuit 113 to the battery cell 120 is as follows: Figure 5C The waveform I2 shown in FIG. 1 , wherein the current value may be the aforementioned 30A, and the voltage waveform of the DC power is as follows: Figure 5D The voltage value of V2 shown in the figure may be the aforementioned 4.5V.

[0084] It can be seen that the DC power input from the charger 200 to the first conversion circuit 111 is high voltage and low current, and the DC power input from the second conversion circuit 113 to the battery cell 120 is low voltage and high current.

[0085] In the present application, the output of the aforementioned DC to AC circuit can be connected to the battery protection board 140 through a flexible board, a connector, etc.

[0086] Furthermore, the charging circuit provided in the present application has a relatively small charging circuit structure, which meets the requirement of miniaturization of the charging circuit structure as the size of electronic devices such as mobile phones 100 is getting smaller and smaller.

[0087] It should be noted that the charging circuit provided in the present application can be used in the constant current charging stage and only works in the constant current charging stage, which can effectively improve the charging power in the constant current charging stage.

[0088] In addition, in the present application, the mobile phone 100 may further include a constant voltage charging circuit (not shown in the figure) and / or a trickle charging circuit (not shown in the figure), both of which can be selected according to needs, and the present application does not make specific limitations on this.

[0089] Furthermore, in the present application, the mobile phone 100 may also include a load (not shown in the figure), and the load is connected to the charging circuit 110 and the battery cell 120 respectively.

[0090] It should be noted that the mobile phone 100 in the present application may also include more other components, which are not limited in the present application.

[0091] In addition, in the present application, the structure and model of the charger 200 can be selected as needed, and the present application does not limit this.

[0092] For further information, see Figure 6The present application also provides a battery 150 , which may include the aforementioned battery protection board 140 and battery cell 120 .

[0093] The battery cell 120 includes a first electrode 121 and a second electrode 122 , both of which are made of metal materials and serve as positive and negative pole tabs of the battery cell 120 , respectively. For example, the first electrode 121 is a positive pole tab, and the second pole 122 is a negative pole tab.

[0094] The battery protection board 140 includes a transformer 112 and a conversion circuit that are connected to each other. The conversion circuit may be the aforementioned second conversion circuit 113 , and the second conversion circuit 113 is connected to the first pole 121 and the second pole 122 , respectively.

[0095] Exemplarily, the second conversion circuit 113 includes a first output terminal 141 and a second output terminal 142 , and the first output terminal 141 and the second output terminal 142 may be metal wires, wherein the first output terminal 141 is connected to the first pole 121 , and the second output terminal 142 is connected to the second pole 122 .

[0096] The transformer 112 is used to step down the voltage of the received alternating current to 1 / N of the voltage of the received alternating current, and output it to the second conversion circuit 113; the second conversion circuit 113 is used to convert the alternating current transmitted by the transformer 112 into direct current, and output it to the battery cell 120 through the first pole 121 and the second pole 122 to charge the battery cell 120.

[0097] It should be noted that the battery protection board 140 may also include other circuit structures such as a protection circuit, which will not be described in detail here.

[0098] For further information, see Figure 7 The battery 150 further includes a packaging shell 151 , in which the battery protection board 140 and the battery cell 120 are packaged.

[0099] It should be noted that the first pole 121 and the second pole 122 also extend out of the packaging shell 151 respectively, which is used to connect with external components. For example, it can be connected to the device motherboard 130 in the aforementioned mobile phone 100 to realize charging of the battery cell 120. It can also be connected to a load to realize the battery cell 120 supplying power to the load.

[0100] The battery protection board 140 can also be fixed by the battery cell 120. For example, the battery protection board 140 can be located on one side of the battery cell 120, and then the battery cell 120 is fixed to the inner wall of the packaging shell 151. It can be arranged as needed.

[0101] The battery provided in the present application, the arrangement of the transformer 112 can achieve a higher voltage transformation ratio, and can achieve a greater current increase. In addition, by arranging the transformer 112 on the battery protection board 140, the distance between the transformer 112 and the battery cell 120 can be effectively reduced. Since the current between the transformer 112 and the battery cell 120 is relatively large, the distance between the transformer 112 and the battery cell 120 is reduced, that is, the large current path is effectively reduced, and the channel impedance between the transformer 112 and the battery cell 120 can be effectively reduced, thereby effectively reducing the temperature rise and power loss generated in the channel. It avoids the problem in the prior art that the switch capacitor circuit is arranged on the device mainboard, and the current between the device mainboard and the battery protection board is relatively large, which makes the power loss from the device mainboard to the battery protection board relatively large, resulting in a large efficiency loss and temperature rise.

[0102] Further, the battery can be applied to the aforementioned mobile phone 100, which includes a device motherboard 130, and the device motherboard 130 may include the aforementioned first conversion circuit 111 and control circuit 114. The connection relationship between the first conversion circuit 111, the control circuit 114, the transformer 112 and the second conversion circuit 113, the battery cell 120, and the charger 200, as well as the current transmission, etc. are not described in detail here.

[0103] In addition, the battery 150 can also be applied to other electronic devices.

[0104] See also Figure 8 The present application also provides a charging method, which includes:

[0105] S10, the electronic device generates indication information according to the voltage of the battery cell in the electronic device, and sends the indication information to the charger;

[0106] S20, the charger adjusts the voltage of the direct current output by the charger to N times the voltage of the battery cell according to the instruction information, where N is greater than or equal to 2;

[0107] S30, the electronic device converts the direct current transmitted from the charger into alternating current, steps down the voltage of the alternating current transmitted from the charger to 1 / N of the voltage of the direct current transmitted from the charger, and converts the stepped-down alternating current into direct current, and outputs it to the battery cell.

[0108] The electronic device generates indication information according to the voltage of the battery cell in the electronic device, and the indication information may include the positive and negative voltages of the battery cell and the voltage transformation ratio N of the transformer, so that the charger adjusts its output voltage to N times the positive and negative voltages of the battery cell according to the positive and negative voltages of the battery cell and the voltage transformation ratio N. In addition, the indication information may also be a voltage value determined by the electronic device that the charger needs to output, so that the charger adjusts its output voltage according to the voltage value.

[0109] Furthermore, the electronic device converts the DC power transmitted from the charger into AC power, and steps down the voltage of the AC power transmitted from the charger to 1 / N of the voltage of the DC power transmitted from the charger, and converts the stepped-down AC power into DC power, and outputs it to the battery cell.

[0110] In the present application, the charging method can conveniently realize the charging of the electronic device by the charger, and since the electronic device includes the aforementioned charging circuit, high-efficiency charging can be realized, which will not be described in detail here. Further, the electronic device can be the aforementioned mobile phone 100.

[0111] It should be noted that the terms “first”, “second”, etc. are only used for distinguishing descriptions and cannot be understood as indicating or implying relative importance.

[0112] It should be noted that in the accompanying drawings, some structural or method features may be shown in a specific arrangement and / or order. However, it should be understood that such a specific arrangement and / or order may not be required. Instead, in some embodiments, these features may be arranged in a manner and / or order different from that shown in the illustrative drawings. In addition, the inclusion of structural or method features in a particular figure does not mean that such features are required in all embodiments, and in some embodiments, these features may not be included or may be combined with other features.

[0113] Obviously, those skilled in the art should understand that the modules or steps of the present application can be implemented with a general computing device, they can be concentrated on a single computing device, or distributed on a network composed of multiple computing devices, and optionally, they can be implemented with program codes executable by a computing device, so that they can be stored in a storage medium (ROM / RAM, magnetic disk, optical disk) and executed by a computing device, and in some cases, the steps shown or described can be executed in a different order from that herein, or they can be made into individual integrated circuit modules, or multiple modules or steps therein can be made into a single integrated circuit module for implementation. Therefore, the present application is not limited to any specific combination of hardware and software.

[0114] Although the present application has been illustrated and described by referring to certain preferred embodiments of the present application, it should be understood by those skilled in the art that the above contents are further detailed descriptions of the present application in combination with specific embodiments, and it cannot be determined that the specific implementation of the present application is limited to these descriptions. Those skilled in the art may make various changes in form and details, including making several simple deductions or substitutions, without departing from the spirit and scope of the present application.

Claims

1. A charging circuit, applied to an electronic device, the charging circuit is used to connect to a charger outside the electronic device and a battery cell of the electronic device respectively, characterized in that: The charging circuit includes a first conversion circuit, a transformer, and a second conversion circuit which are cascaded in sequence, and the current provided by the charger is input into the first conversion circuit and provided to the battery cell via the transformer and the second conversion circuit; The charging circuit further includes a control circuit, and the control circuit is used to be connected to the charger and the battery cell respectively; and, The control circuit is used to adjust the voltage of the direct current provided by the charger to N times the voltage of the battery cell based on the voltage of the battery cell, where N is greater than or equal to 2; The first conversion circuit is used to convert the direct current transmitted by the charger into alternating current and output it to the transformer; The transformer is used to step down the voltage of the alternating current transmitted by the first conversion circuit to 1 / N of the voltage of the alternating current transmitted by the first conversion circuit, and output it to the second conversion circuit; The second conversion circuit is used to convert the alternating current transmitted by the transformer into direct current and output it to the battery cell.

2. The charging circuit according to claim 1, characterized in that: The first conversion circuit includes a DC to AC circuit, and the second conversion circuit includes an AC to DC circuit.

3. The charging circuit according to claim 2, characterized in that: The DC to AC circuit is a full-bridge rectifier circuit for converting DC power into AC power.

4. The charging circuit according to claim 2, characterized in that: The first conversion circuit also includes an inductor connected to the DC-to-AC circuit and the transformer respectively, and the second conversion circuit also includes a capacitor connected to the AC-to-DC circuit and the transformer respectively, and the inductor and the capacitor form an LC resonant circuit.

5. The charging circuit according to claim 1, characterized in that: The control circuit is used to detect the positive and negative voltages of the battery cell to obtain the voltage of the battery cell.

6. The charging circuit according to any one of claims 1 to 5, characterized in that: The control circuit is also used to be connected to the first conversion circuit and the second conversion circuit respectively; The control circuit is further used to control the first conversion circuit to convert direct current into alternating current, and to control the second conversion circuit to convert alternating current into direct current.

7. The charging circuit according to any one of claims 1 to 5, characterized in that: When the battery cell is charged with a constant current, the control circuit is used to adjust the voltage of the direct current provided by the charger to N times the voltage of the battery cell based on the voltage of the battery cell.

8. The charging circuit according to any one of claims 1 to 5, characterized in that: The charging circuit is used to connect to the charger via a universal serial bus.

9. An electronic device, characterized in that: The electronic device comprises a battery and a charging circuit as claimed in any one of claims 1 to 8.

10. The electronic device according to claim 9, characterized in that: The battery comprises a battery cell and a battery protection board, wherein: The battery cell comprises a first pole and a second pole; The battery protection board includes the transformer and the second conversion circuit connected to each other, and the second conversion circuit is connected to the first pole and the second pole respectively; wherein, The transformer is used to step down the voltage of the received alternating current to 1 / N of the voltage of the received alternating current, and output it to the second conversion circuit; The second conversion circuit is used to convert the alternating current transmitted by the transformer into direct current and output it to the battery cell.

11. The electronic device according to claim 10, characterized in that: The battery further comprises a packaging shell, wherein the battery cell and the battery protection board are arranged in the packaging shell.

12. The electronic device according to claim 9 or 10, characterized in that: The electronic device further comprises a device mainboard, and the control circuit and the first conversion circuit are arranged on the device mainboard.

13. A charging system, characterized in that: include: A charger and an electronic device connected to each other, wherein the electronic device is the electronic device according to any one of claims 9 to 12; wherein, The electronic device is used to generate indication information according to the voltage of the battery cell in the electronic device, and send the indication information to the charger; The charger is used to adjust the voltage of the direct current provided by the charger to N times the voltage of the battery cell according to the indication information, where N is greater than or equal to 2; The electronic device is also used to convert the direct current transmitted by the charger into alternating current, and to reduce the voltage of the alternating current to 1 / N of the voltage of the direct current transmitted by the charger, and to convert the reduced alternating current into direct current and output it to the battery cell.

14. A charging method, characterized in that: Applicable to a charger and an electronic device connected to each other, the electronic device is the electronic device according to any one of claims 9 to 12; the charging method comprises: The electronic device generates indication information according to the voltage of the battery cell in the electronic device, and sends the indication information to the charger; The charger adjusts the voltage of the direct current output by the charger to N times the voltage of the battery cell according to the instruction information, where N is greater than or equal to 2; The electronic device converts the direct current transmitted from the charger into alternating current, reduces the voltage of the alternating current transmitted from the charger to 1 / N of the voltage of the direct current transmitted from the charger, and converts the reduced alternating current into direct current, and outputs it to the battery cell.

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