Wireless charging device

Abstract

The present application discloses a wireless charging device, which is coupled to an antenna and a battery and is used to charge the battery according to an electric field signal received from the antenna. The wireless charging device includes a low-frequency blocking circuit, a rectifying circuit, a charging path control circuit, a filter capacitor, an overvoltage protection circuit, a battery management circuit, a near-field communication controller, and a matching filter circuit. The low-frequency blocking circuit is used to block low-frequency noise in the electric field signal. The rectifying circuit is used to convert the electric field signal into a DC signal. The charging path control circuit is used to turn on or off the charging path to the battery according to a charging control signal. The filter capacitor is used to smooth the waveform of the DC signal when the charging path is turned on. The overvoltage protection circuit is used to reduce the voltage value of the DC signal when the voltage of the DC signal exceeds a critical value. The battery management circuit is used to provide a charging power supply to the battery according to the DC signal. The near-field communication controller is used to generate a charging control signal.

Description

Technical Field

[0001] This application relates to a wireless charging device, and more particularly to a wireless charging device sharing an antenna with near field communication. Background Art

[0002] Due to the increasing requirements for product waterproofness of smart wearable devices and small smart devices, traditional charging connectors usually cannot meet the high waterproofness requirements. In addition, the efficiency of wireless charging has been gradually improved, so wireless charging has become a common charging method for smart wearable devices and small smart devices. During wireless charging, necessary communications are often required, and these communication messages include device anti-counterfeiting authentication, product pairing, wireless charging handshake, charging parameter monitoring, and charging process monitoring, and are usually communicated through near field communication. In addition, due to the small size of smart wearable devices and small smart devices, near field communication and wireless charging often share the same antenna coil, that is, the so-called integration of wireless charging and communication, so as to reduce the space requirement.

[0003] However, wireless charging needs to use a larger capacitor to stabilize the waveform of the charging voltage, so it will affect the matching impedance when near field communication receives and transmits signals through the antenna, resulting in difficulty in improving the signal quality of near field communication. Conversely, the matching impedance required for near field communication will also cause a smaller conduction angle of the rectifier, thereby reducing the efficiency of wireless charging. Since the wireless charging circuit and the near field communication circuit need to share the same line, there will be a phenomenon of mutual restriction between the charging efficiency and the communication quality. Therefore, how to improve the efficiency of wireless charging and not affect the quality of near field communication when sharing an antenna has become a problem to be solved in this field. Summary of the Invention

[0004] One object of this application is to disclose a wireless charging device capable of sharing an antenna with near field communication to solve the above problems.

[0005] An embodiment of the present application provides a wireless charging device, which is coupled to an antenna and a battery and is used to charge the battery according to an electric field signal received from the antenna. The wireless charging device includes a low-frequency blocking circuit, a rectifying circuit, a charging path control circuit, a filtering capacitor, an overvoltage protection circuit, a battery management circuit, a near-field communication controller, and a matching filtering circuit. The low-frequency blocking circuit is coupled to the antenna and is used to block low-frequency noise in the electric field signal. The rectifying circuit is coupled to the low-frequency blocking circuit and is used to convert the electric field signal into a DC signal. The charging path control circuit is coupled to the rectifying circuit and is used to turn on or off the charging path of the DC signal to the battery according to a charging control signal. The filtering capacitor is coupled to the charging path control circuit and is used to smooth the waveform of the DC signal when the charging path is turned on. The overvoltage protection circuit is coupled to the filtering capacitor and is used to reduce the voltage value of the DC signal when the voltage of the DC signal exceeds a critical value. The battery management circuit is coupled to the overvoltage protection circuit and is used to provide a charging power supply to the battery according to the DC signal. The near-field communication controller is coupled to the charging path control circuit and is used to generate the charging control signal and a near-field communication signal. The matching filtering circuit is coupled to the antenna and the near-field communication controller and is used to provide an impedance matching the antenna to transmit the near-field communication signal through the antenna.

[0006] The wireless charging device of the present application can share an antenna with near-field communication and can separate the paths of near-field communication and wireless charging. Therefore, the efficiency of wireless charging can be improved without affecting the quality of near-field communication. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Figure 1 is a functional block diagram of a wireless charging device according to an embodiment of the present application.

[0008] Figure 2 is Figure 1 another schematic diagram of the wireless charging device.

[0009] Figure 3 is a schematic diagram of a wireless charging device according to another embodiment of the present application. DETAILED DESCRIPTION

[0010] The following disclosure provides various embodiments or illustrations that can be used to implement different features of the present disclosure. Specific examples of components and configurations described below are used to simplify the present disclosure. It will be appreciated that these descriptions are merely illustrative and are not intended to limit the present disclosure. For example, in the following description, forming a first feature on or above a second feature may include, in some embodiments, the first and second features being in direct contact with each other; and may also include, in some embodiments, additional components being formed between the first and second features such that the first and second features may not be in direct contact. Additionally, the present disclosure may reuse component symbols and / or reference numerals in multiple embodiments. Such reuse is for the purpose of simplicity and clarity and does not in itself represent a relationship between the different embodiments and / or configurations being discussed.

[0011] Furthermore, the spatially relative terms used herein, such as "below", "beneath", "lower", "above", "upper" and the like, may be used for convenience in describing the relationship of one component or feature shown in the figures to another or other components or features. These spatially relative terms are intended to cover not only the orientation shown in the figures but also various different orientations of the device during use or operation. The device may be placed in other orientations (e.g., rotated 90 degrees or in other orientations), and these spatially relative descriptive terms should be interpreted accordingly.

[0012] Although the numerical ranges and parameters defining the broader scope of the present application are approximate values, the relevant values in the specific embodiments are presented as precisely as possible herein. However, any numerical value inherently contains standard deviations due to the individual testing methods. Herein, "about" generally means that the actual value is within plus or minus 10%, 5%, 1% or 0.5% of a particular value or range. Alternatively, the term "about" represents that the actual value falls within the acceptable standard error of the mean, depending on the consideration of those of ordinary skill in the art to which the present application pertains. It will be understood that, except for experimental examples or unless otherwise expressly stated, all ranges, amounts, numerical values and percentages (e.g., describing amounts of materials, lengths of time, temperatures, operating conditions, ratios of amounts and other similar things) used herein are modified by "about". Accordingly, unless otherwise stated to the contrary, the numerical parameters disclosed in this specification and the appended claims are approximate values and may be varied as desired. At the very least, these numerical parameters should be construed as the values indicated by the effective digits and the application of ordinary rounding methods. Herein, a numerical range is expressed as extending from one endpoint to the other endpoint or as being between two endpoints; unless otherwise stated, the numerical ranges described herein include the endpoints.

[0013] Figure 1It is a functional block diagram of a wireless charging device 100 according to an embodiment of the present application. In this embodiment, the wireless charging device 100 can be coupled to an antenna AT1 and a battery BT1, and can charge the battery BT1 according to the electric field signal ES1 received from the antenna AT1.

[0014] The wireless charging device 100 may include a low-frequency blocking circuit 110, a rectifying circuit 120, a charging path control circuit 130, a filter capacitor C F , an overvoltage protection circuit 140, a battery management circuit 150, a matching filter circuit 160, and a near-field communication controller 170.

[0015] The low-frequency blocking circuit 110 can be coupled to the antenna AT1 and can block the low-frequency noise in the electric field signal ES1. The rectifying circuit 120 can be coupled to the low-frequency blocking circuit 110 and can convert the electric field signal ES1 transmitted in the form of alternating current into a direct current signal DS1. The charging path control circuit 130 can be coupled to the rectifying circuit 120 and can turn on or off the charging path of the direct current signal DS1 to the battery BT1 according to the charging control signal SIG CC to the battery BT1.

[0016] The filter capacitor C F can be coupled to the charging path control circuit 130 and can smooth the waveform of the direct current signal DS1 when the charging path is turned on. The overvoltage protection circuit 140 can be coupled to the filter capacitor C F , and when the voltage of the direct current signal DS1 exceeds the critical value, the overvoltage protection circuit 140 can reduce the voltage value of the direct current signal DS1. The battery management circuit 150 can be coupled to the overvoltage protection circuit 140 and can provide a charging power supply to the battery BT1 according to the direct current signal DS1.

[0017] The near-field communication controller 170 can be coupled to the charging path control circuit 130 and can generate a charging control signal SIG CC to control the charging path control circuit 130 to turn on or off the charging path of the direct current signal DS1 to the battery BT1. For example, when the near-field communication controller 170 does not perform near-field communication through the antenna AT1, the near-field communication controller 170 can turn on the charging path to the battery BT1, and when the near-field communication controller 170 needs to send a near-field communication signal through the antenna AT1, the near-field communication controller 170 can turn off the charging path to the battery BT1.

[0018] In addition, the matching filter circuit 160 can be coupled to the antenna AT1 and the near field communication controller 170. When the near field communication controller 170 desires to transmit a near field communication signal through the antenna AT1, the matching filter circuit 160 can provide an impedance matching the antenna AT1 to transmit the near field communication signal through the antenna AT1. In this embodiment, when the near field communication controller 170 stops generating the near field communication signal, in addition to controlling the charging path control circuit 130 to turn on the charging path, the near field communication controller 170 can also control the matching filter circuit 160 through the impedance adjustment signal SIG IA to increase the impedance of the matching filter circuit 160, thereby reducing the wireless charging electric field signal ES1 from entering the near field communication controller 170 through the matching filter circuit 160. Conversely, when the near field communication controller 170 desires to transmit a near field communication signal through the antenna AT1, in addition to controlling the charging path control circuit 130 to cut off the charging path, the near field communication controller 170 can also control the matching filter circuit 160 through the impedance adjustment signal SIG IA to adjust the impedance of the matching filter circuit 160 for the transmission of the near field communication signal.

[0019] Since the near field communication controller 170 can control the charging path control circuit 130 to turn on or cut off the charging path according to whether it is necessary to transmit a near field communication signal through the antenna AT1, and can correspondingly adjust the impedance of the matching filter circuit 160, the wireless charging device 100 can separate the paths of near field communication and wireless charging, reducing the situation where the wireless charging efficiency and the near field communication quality restrict each other, so that the wireless charging efficiency can be improved without affecting the near field communication quality. However, in some other embodiments, when the matching filter circuit 160 provides a fixed impedance, if it is already possible to effectively reduce the electric field signal ES1 from entering the near field communication controller 170, and it is also possible to allow the near field communication signal to enter the near field communication controller 170 through the matching filter circuit 160 during near field communication, the matching filter circuit 160 can be kept at providing a fixed impedance, and the near field communication controller 170 does not need to additionally generate an impedance adjustment signal SIG IA to control the matching filter circuit 160.

[0020] Figure 2 is another schematic diagram of the wireless charging device 100. In Figure 2In [the circuit], the low-frequency blocking circuit 110 may include a first capacitor C1 and a second capacitor C2. The first capacitor C1 has a first end and a second end, and the first end of the first capacitor C1 may be coupled to the first end of the antenna AT1. The second capacitor C2 has a first end and a second end, the first end of the second capacitor C2 may be coupled to the second end of the first capacitor C1, and the second end of the second capacitor C2 may be coupled to the second end of the antenna AT1. In this embodiment, the first capacitor C1 may block low-frequency noise in the electric field signal ES1, and the second capacitor C2 and the first capacitor C1 may also divide the voltage of the electric field signal ES1, such that the rectifying circuit 120 can receive a voltage within an appropriate range.

[0021] The rectifying circuit 120 includes a first inductor L1, a second inductor L2, a first diode D1, a second diode D2, a third diode D3, and a fourth diode D4. The first inductor L1 has a first end and a second end, and the first end of the first inductor L1 may be coupled to the second end of the first capacitor C1. The second inductor L2 has a first end and a second end, and the first end of the second inductor L2 may be coupled to the second end of the second capacitor C2.

[0022] The first diode D1 has a first end and a second end, the first end of the first diode D1 may be coupled to the second end of the first inductor L1, and the second end of the first diode D1 may be coupled to the output end of the rectifying circuit 120. The second diode D2 has a first end and a second end, the first end of the second diode D2 may be coupled to the second end of the second inductor L2, and the second end of the second diode D2 may be coupled to the output end of the rectifying circuit 120. The third diode D3 has a first end and a second end, the first end of the third diode D3 may be coupled to the ground terminal GND, and the second end of the third diode D3 may be coupled to the second end of the first inductor L1. The fourth diode D4 has a first end and a second end, the first end of the fourth diode D4 may be coupled to the ground terminal GND, and the second end of the fourth diode D4 may be coupled to the second end of the second inductor L2.

[0023] In this embodiment, the first ends of the first diode D1, the second diode D2, the third diode D3, and the fourth diode D4 may be the anodic ends, and the second ends of the first diode D1, the second diode D2, the third diode D3, and the fourth diode D4 may be the cathodic ends. In the rectifying circuit 120, the first diode D1, the second diode D2, the third diode D3, and the fourth diode D4 may rectify the electric field signal ES1, converting the originally AC-input electric field signal ES1 into a DC signal DS1.

[0024] In addition, since the electric field signal ES1 is an alternating current, if the electric field signal ES1 attenuates during transmission, the conduction angles of the first diode D1, the second diode D2, the third diode D3, and the fourth diode D4 may be small. Furthermore, since the first capacitor C1 and the second capacitor C2 are high-pass filter components, it is difficult to increase the conduction angles of the first diode D1, the second diode D2, the third diode D3, and the fourth diode D4 with respect to the electric field signal ES1. In contrast, the first inductor L1 and the second inductor L2 can generate self-induced electromotive forces, causing the waveform change of the electric field signal ES1 to slow down, thereby increasing the conduction angles of the first diode D1, the second diode D2, the third diode D3, and the fourth diode D4 with respect to the electric field signal ES1 and improving the efficiency of wireless charging.

[0025] Since the wireless charging device 100 can separate the paths of near-field communication and wireless charging, in the rectifier circuit 120, the first inductor L1 and the second inductor L2 used to increase the conduction angle can, on the one hand, improve the efficiency of inefficient charging, and on the other hand, do not affect the satisfaction of the impedance matching condition by the matching filter circuit on the near-field communication path. Conversely, it will not be unable to increase the conduction angle of the rectifier circuit due to taking into account the matching circuit required for near-field communication. Therefore, the wireless charging device 100 of this embodiment can well balance the quality of near-field communication and better charging efficiency.

[0026] In some embodiments, if the conduction angles of the rectifier circuit 120 can already meet the requirements, the first inductor L1 and the second inductor L2 can also be omitted. At this time, the first end of the first diode D1 can be coupled to the second end of the first capacitor C1, the first end of the second diode D2 can be coupled to the second end of the second capacitor C2, the second end of the third diode D3 can be coupled to the second end of the first capacitor C1, and the second end of the fourth diode D4 can be coupled to the second end of the second capacitor C2.

[0027] In Figure 1 , the charging path control circuit 130 may include a first transistor T1, a second transistor T2, a control driver 132, and a first resistor R1. The first transistor T1 has a first end, a second end, and a control end. The second end of the first transistor T1 can be coupled to the ground terminal GND, and the control end of the first transistor T1 can receive a charging control signal SIG CC . The second transistor T2 has a first end, a second end, and a control end. The first end of the second transistor T2 can receive a DC signal DS1, and the second end of the second transistor T2 can be coupled to a filter capacitor C F . The first resistor R1 has a first end and a second end. The first end of the first resistor R1 can be coupled to the first end of the second transistor T2, and the second end of the first resistor R1 can be coupled to the control end of the second transistor T2.

[0028] The control driver 132 can be coupled to the first end of the first transistor T1 and the control end of the second transistor T2. The control driver 132 can turn on or off the second transistor T2 according to the voltage at the first end of the first transistor T1 so that the charging path is turned on or off. In this embodiment, the control driver 132 can include a third transistor T3. The third transistor T3 has a first end, a second end, and a control end. The first end of the third transistor T3 can be coupled to the control end of the second transistor T2. The second end of the third transistor T3 can be coupled to the ground terminal GND, and the control end of the third transistor T3 can be coupled to the first end of the first transistor T1.

[0029] For example, the first transistor T1 and the third transistor T3 can be, for example but not limited to, N-type transistors, and the second transistor T2 can be, for example but not limited to, a P-type transistor. In this case, when the charging control signal SIG CC is at a high potential, the first transistor T1 is turned on, and the control end voltage of the third transistor T3 is pulled down to a low potential close to the system voltage GND, so that the third transistor T3 is turned off. At this time, when the charging path control circuit 130 has received the DC signal DS1, the DC signal DS1 will raise the control end voltage of the second transistor T2 through the first resistor R1, so that the second transistor T2 is turned off, thereby turning off the charging path of the DC signal DS1 to the battery BT1. On the contrary, if the charging control signal SIG CC is at a low potential, the first transistor T1 is turned off. In this embodiment, the control end of the third transistor T3 can receive a bias voltage related to the electric field signal ES1. Therefore, when the wireless charging device 100 receives the electric field signal ES1 and the first transistor T1 is turned off, the third transistor T3 is turned on, so that the control end voltage of the second transistor T2 is pulled down to a low potential close to the system voltage GND. At this time, the second transistor T2 will be turned on, thereby turning on the charging path of the DC signal DS1 to the battery BT1.

[0030] That is to say, the near-field communication controller 170 can correspondingly turn on or off the charging path of the DC signal DS1 to the battery BT1 by adjusting the potential of the charging control signal SIG CC . In addition, in Figure 2 , the wireless charging device 100 can further include an electric field detection circuit 180. The electric field detection circuit 180 can generate a charging detection signal CD1 related to the voltage magnitude of the DC signal DS1 based on the DC signal DS1, so that the near-field communication controller 170 can further generate a charging control signal SIG CC .

[0031] For example, the near field communication controller 170 can determine the strength of the DC signal DS1 based on the charging detection signal CD1. When the DC signal DS1 is large, it indicates that there is an external power source available for wireless charging. At this time, the near field communication controller 170 can make the charging control signal SIG CC at a low potential to correspondingly conduct the charging path of the DC signal DS1 to the battery BT1. Conversely, when the DC signal DS1 is too small, it indicates that there is no external power source available for wireless charging. At this time, the near field communication controller 170 can make the charging control signal SIG CC at a high potential to correspondingly cut off the charging path of the DC signal DS1 to the battery BT1.

[0032] In this embodiment, the electric field detection circuit 180 may include a filter clamping unit 182 and a voltage dividing unit 184. The filter clamping unit 182 can filter the DC signal DS1 to generate an electric field reference signal ER1, and the voltage dividing unit 184 can generate a charging detection signal CD1 by dividing the voltage of the electric field reference signal ER1.

[0033] The filter clamping unit 182 may include a third resistor R3, a fourth capacitor C4, and a first clamping diode TSV1. The third resistor R3 has a first end and a second end, and the first end of the third resistor R3 can receive the DC signal DS1. The fourth capacitor C4 has a first end and a second end, the first end of the fourth capacitor C4 can be coupled to the second end of the third resistor R3 and can output the electric field reference signal ER1, and the second end of the fourth capacitor C4 can be coupled to the ground terminal GND. The first clamping diode TSV1 has a first end and a second end, the first end of the first clamping diode TSV1 can be coupled to the first end of the fourth capacitor C4, and the second end of the first clamping diode TSV1 can be coupled to the second end of the fourth capacitor C4. In this embodiment, the third resistor R3 and the fourth capacitor C4 can filter the DC signal DS1 to make the waveform of the electric field reference signal ER1 more stable. In addition, the first clamping diode TSV1 can provide a pressure relief path to clamp the electric field reference signal ER1 within a safe voltage range when the voltage of the DC signal DS1 is too large. In this case, the first end of the first transistor T1 and the control end of the third transistor T3 can be coupled to the second end of the third resistor R3 to receive the electric field reference signal ER1 as the bias voltage during operation.

[0034] The voltage dividing unit 184 includes a fourth resistor R4 and a fifth resistor R5. The fourth resistor has a first end and a second end, and the first end of the fourth resistor R4 can receive an electric field reference signal ER1. The fifth resistor R5 has a first end and a second end. The first end of the fifth resistor R5 can be coupled to the second end of the fourth resistor R4 and can output a charging detection signal CD1, and the second end of the fifth resistor R5 can be coupled to the ground terminal GND. In this embodiment, the fourth resistor R4 and the fifth resistor R5 can divide the voltage of the electric field reference signal ER1 to generate the charging detection signal CD1.

[0035] In this embodiment, the wireless charging device 100 detects the DC signal DS1 through the electric field detection circuit 180 to generate the charging detection signal CD1. However, the present application is not limited thereto. In some other embodiments, the wireless charging device 100 can detect the presence of the wireless charging electric field through a detection circuit of other types or structures. For example, the wireless charging device 100 can use an electric field detection circuit capable of detecting alternating current to detect the electric field signal ES1 to generate a corresponding charging detection signal, so that the near field communication controller 170 can determine whether the wireless charging electric field exists and further conduct or cut off the charging path of the battery BT1. In addition, in some embodiments, if the near field communication controller 170 can determine the wireless charging timing through other means, the wireless charging device 100 can also omit the electric field detection circuit 180, as Figure 1 shown.

[0036] In Figure 2 it, the overvoltage protection circuit 140 may include a first voltage dividing component 142, a second voltage dividing component 144, a sixth resistor R6, and a fourth transistor T4. The first voltage dividing component 142 has a first end and a second end, and the first end of the first voltage dividing component 142 can receive the DC signal DS1. The second voltage dividing component 144 has a first end and a second end. The first end of the second voltage dividing component 144 can be coupled to the second end of the first voltage dividing component 142, and the second end of the second voltage dividing component 144 can be coupled to the ground terminal GND. In this embodiment, both the first voltage dividing component 142 and the second voltage dividing component 144 are implemented by using resistors, and the first voltage dividing component 142 and the second voltage dividing component 144 can divide the voltage of the DC signal DS1 to generate an overvoltage reference signal OV1.

[0037] The sixth resistor R6 has a first end and a second end, and the first end of the sixth resistor R6 can receive a DC signal DS1. The fourth transistor T4 has a first end, a second end, and a control end. The first end of the fourth transistor T4 can be coupled to the second end of the sixth resistor R6. The second end of the fourth transistor T4 can be coupled to the ground terminal GND, and the control end of the fourth transistor T4 can be coupled to the second end of the first voltage dividing component 142. The fourth transistor T4 can turn on a pressure relief path formed jointly by the fourth transistor T4 and the sixth resistor R6 according to the overvoltage reference signal OV1 to reduce the voltage value of the DC signal DS1.

[0038] In some embodiments, if the overvoltage reference signal OV1 causes the fourth transistor T4 to operate in the saturation region, once the voltage of the DC signal DS1 is too high, the fourth transistor T4 will be completely cut off. At this time, the DC signal DS1 will flow into the ground terminal GND through the pressure relief path, making the battery management circuit 150 unable to charge the battery BT1 based on the DC signal DS1. However, in this embodiment, the overvoltage reference signal OV1 can be set within an appropriate range through the first voltage dividing component 142 and the second voltage dividing component 144, so that the fourth transistor T4 mainly operates in the linear region. Therefore, the fourth transistor T4 can control the conduction degree of the pressure relief path according to the magnitude of the overvoltage reference signal OV1. In this way, the DC signal DS1 passing through the overvoltage protection circuit 140 can be maintained within an appropriate voltage range to a limited extent, extending the time during which the battery management circuit 150 can receive the DC signal DS1 and charge the battery BT1, and enabling the charging efficiency of the wireless charging device 100 to be further improved.

[0039] In this case, in order to provide real-time protection when the DC signal DS1 is overvoltage, the overvoltage protection circuit 140 may further include a second clamping diode TSV2. The second clamping diode TSV2 has a first end and a second end. The first end of the second clamping diode TSV2 can receive the DC signal DS1, and the second end of the second clamping diode TSV2 can be coupled to the ground terminal GND. In this way, when the DC signal DS1 is overvoltage, the second clamping diode TSV2 will conduct and provide a pressure relief path to prevent the battery management circuit 150 from being damaged due to receiving high voltage.

[0040] In addition, the overvoltage protection circuit 140 may further include a third voltage dividing component 146 and a fourth voltage dividing component 148. The third voltage dividing component 146 has a first end and a second end. The first end of the third voltage dividing component 146 may receive a DC signal DS1, and the second end of the third voltage dividing component 146 may output an overvoltage detection signal OD1. The fourth voltage dividing component 148 has a first end and a second end. The first end of the fourth voltage dividing component 148 may be coupled to the second end of the third voltage dividing component 146, and the second end of the fourth voltage dividing component 148 may be coupled to the ground terminal GND. In this embodiment, the third voltage dividing component 146 is a clamping diode, and the fourth voltage dividing component 148 is a resistor.

[0041] The third voltage dividing component 146 and the fourth voltage dividing component 148 can divide the voltage of the DC signal DS1 to generate an overvoltage detection signal OD1, and the near field communication controller 170 can determine whether the DC signal DS1 is overvoltage according to the overvoltage detection signal OD1, and can generate a charging control signal SIG accordingly. CC To turn on or off the charging path of the battery BT1. In addition, the third voltage dividing component 146 and the fourth voltage dividing component 148 can also be used to provide a voltage relief path for the DC signal DS1 to further achieve the function of overvoltage protection, making the operation of the wireless charging device 100 safer.

[0042] In Figure 1 , the wireless charging device 100 may further include a power management circuit 190, and the power management circuit 190 may be coupled to the battery management circuit 150. In this case, the battery management circuit 150 can output a supply power to the power management circuit 190 according to the DC signal DS1, and the power management circuit 190 can provide the power required by the near field communication controller 170 according to the supply power. That is to say, the electric energy obtained through wireless charging can not only be used to charge the battery BT1, but also be provided to the near field communication controller 170, so as to use the power obtained through wireless charging more efficiently.

[0043] Since the wireless charging device 100 can separate the paths of near - field communication and wireless charging, the wireless charging device 100 can set inductors L1 and L2 in the rectifier circuit 120 to increase the conduction angles of diodes D1, D2, D3, and D4 in the rectifier circuit 120, thereby improving the efficiency of wireless charging. In addition, the electric - field detection circuit 180 can generate a charging detection signal CD1 for the near - field communication controller 170 to determine whether there is an electric - field signal ES1 capable of providing wireless charging, and accordingly turn on or off the charging - path control circuit 130, so that the wireless charging device 100 can switch more smoothly between the two functions of wireless charging and near - field communication. Moreover, since the over - voltage protection circuit 140 can set the over - voltage reference signal OV1 within an appropriate range, enabling the fourth transistor T4 to mainly operate in the linear region, the DC signal DS1 passing through the over - voltage protection circuit 140 can be maintained within an appropriate voltage range to a certain extent, extending the time for the battery management circuit 150 to receive the DC signal DS1 and charge the battery BT1, thus further improving the charging efficiency of the wireless charging device 100.

[0044] Figure 3 is a schematic diagram of a wireless charging device 200 according to another embodiment of the present application. The wireless charging device 200 has a similar structure to the wireless charging device 100 and can operate based on a similar principle. The wireless charging device 200 may include a low - frequency blocking circuit 210, a rectifier circuit 220, a charging - path control circuit 230, a filter capacitor C F , an over - voltage protection circuit 240, a battery management circuit 250, a matching filter circuit 260, a near - field communication controller 270, a filter clamping unit 282, and a power management circuit 290.

[0045] In Figure 3 , the low - frequency blocking circuit 210 may include a first capacitor C1, a second capacitor C2, and a third capacitor C3. The first capacitor C1 and the second capacitor C2. The first capacitor C1 has a first end and a second end, and the first end of the first capacitor C1 may be coupled to the first end of the antenna AT1. The second capacitor C2 has a first end and a second end, and the first end of the second capacitor C2 may be coupled to the second end of the first capacitor C1. The third capacitor C3 has a first end and a second end, and the first end of the third capacitor C3 may be coupled to the second end of the antenna AT1, while the second end of the third capacitor C3 may be coupled to the second end of the second capacitor C2. In this embodiment, the first capacitor C1 and the third capacitor C3 can block the low - frequency noise in the electric - field signal ES1, and the second capacitor C2 can divide the voltage of the electric - field signal ES1 together with the first capacitor C1 and the third capacitor C3, so that the rectifier circuit 220 can receive a voltage within an appropriate range.

[0046] In addition, the wireless charging device 200 can generate the bias voltages required for the transistors T1B and T3 in the charging path control circuit 230 through the filter clamping unit 282. That is, in Figure 3 In the embodiment, the wireless charging device 200 does not provide the charging detection signal CD1 to the near field communication controller 270 through the electric field detection circuit 180. In this case, the charging detection signal CD1 can be generated by other circuits for the near field communication controller 270 to determine whether there is an electric field signal ES1, or in some embodiments, the near field communication controller 270 can also control the charging path control circuit 230 according to other signals or other rules.

[0047] Furthermore, in Figure 3 In, the charging path control circuit 230 can change the metal oxide semiconductor field effect transistor T1 in the charging path control circuit 130 to a bipolar transistor T1B, and the charging path control circuit 230 can further include a second resistor R2. The second resistor R2 has a first end and a second end. The first end of the second resistor R2 is coupled to the control end of the first transistor T1B, and the second end of the second resistor R2 is coupled to the second end of the first transistor T1B.

[0048] Similarly, in some embodiments, the second transistor T2 and the third transistor T3 can also be implemented with bipolar transistors. However, since the third transistor T3 is disposed on the charging path of the battery BT1, a relatively large current needs to be conducted. In this case, selecting a metal oxide semiconductor field effect transistor with a smaller on-resistance to implement the third transistor T3 will help improve the overall charging efficiency.

[0049] Furthermore, in the overvoltage protection circuit 240, the first voltage dividing component 242 is implemented with a clamping diode, and the second voltage dividing component 244 is implemented with a resistor. The first voltage dividing component 242 and the second voltage dividing component 244 can divide the DC signal DS1 to generate an overvoltage reference signal OV1. That is, according to system requirements, the first voltage dividing component 242 can be implemented with a clamping diode or a resistor. Similarly, the third voltage dividing component 246 can also be implemented with a clamping diode or a resistor. For example, in Figure 3 In, the third voltage dividing component 246 is a clamping diode, and the fourth voltage dividing component 218 is a resistor.

[0050] In summary, the wireless charging device provided by the embodiments of the present application can separate the paths of near-field communication and wireless charging. Therefore, the efficiency of wireless charging can be improved without affecting the quality of near-field communication. For example, the wireless charging device can set an inductor in the rectifier circuit to increase the conduction angle of the rectifier circuit, thereby improving the efficiency of wireless charging. In addition, the wireless charging device can determine whether there is an electric field signal capable of providing wireless charging, and accordingly turn on or off the charging path control circuit, so that the wireless charging device can switch more smoothly between the two functions of wireless charging and near-field communication. Furthermore, since the overvoltage protection circuit of the wireless charging device can set the overvoltage reference signal within an appropriate range, the time for the battery management circuit to receive the DC signal and charge the battery can be extended, so that the charging efficiency of the wireless charging device can be further improved.

[0051] The foregoing description briefly presents the features of certain embodiments of the present application, enabling those of ordinary skill in the art to which the present application pertains to more comprehensively understand the various aspects of the present disclosure. Those of ordinary skill in the art to which the present application pertains should understand that they can easily use the present disclosure as a basis to design or modify other processes and structures to achieve the same purpose and / or the same advantages as the embodiments described herein. Those of ordinary skill in the art to which the present application pertains should understand that these equivalent embodiments still fall within the spirit and scope of the present disclosure, and various changes, substitutions, and modifications can be made thereto without departing from the spirit and scope of the present disclosure.

Claims

1. A wireless charging device, coupled to an antenna and a battery, for charging the battery according to an electric field signal received from the antenna, characterized in that, The wireless charging device includes: A low-frequency blocking circuit, coupled to the antenna, for blocking low-frequency noise in the electric field signal; A rectification circuit, coupled to the low-frequency blocking circuit, for converting the electric field signal into a DC signal; A charging path control circuit, coupled to the rectification circuit, for conducting or blocking the charging path of the DC signal to the battery according to a charging control signal; A filter capacitor, coupled to the charging path control circuit, for smoothing the waveform of the DC signal when the charging path is conducted; An overvoltage protection circuit, coupled to the filter capacitor, for reducing the voltage value of the DC signal when the voltage of the DC signal exceeds a critical value; A battery management circuit, coupled to the overvoltage protection circuit, for providing a charging power supply to the battery according to the DC signal; A near-field communication controller, coupled to the charging path control circuit, for generating the charging control signal and the near-field communication signal; and A matching filter circuit, coupled to the antenna and the near-field communication controller, for providing an impedance matching the antenna to transmit the near-field communication signal through the antenna; Wherein the charging path control circuit includes: A first transistor, having a first end, a second end and a control end, the second end of the first transistor is coupled to a ground end, and the control end of the first transistor is for receiving the charging control signal; A second transistor, having a first end, a second end and a control end, the first end of the second transistor is for receiving the DC signal, and the second end of the second transistor is coupled to the filter capacitor; and A control driver, coupled to the first end of the first transistor and the control end of the second transistor, the control driver is for conducting or blocking the second transistor according to the voltage at the first end of the first transistor so that the charging path is conducted or blocked.

2. The wireless charging device according to claim 1, wherein the low-frequency blocking circuit includes: A first capacitor, having a first end and a second end, the first end of the first capacitor is coupled to the first end of the antenna; And A second capacitor, having a first end and a second end, the first end of the second capacitor is coupled to the second end of the first capacitor, and the second end of the second capacitor is coupled to the second end of the antenna; Wherein: The first capacitor is for blocking the low-frequency noise in the electric field signal; And The second capacitor and the first capacitor are for dividing the voltage of the electric field signal.

3. The wireless charging device according to claim 2, wherein the low-frequency blocking circuit further includes: A third capacitor, having a first end and a second end, the first end of the third capacitor is coupled to the second end of the antenna, and the second end of the third capacitor is coupled to the second end of the second capacitor; Wherein: The third capacitor is for blocking the low-frequency noise in the electric field signal; and The second capacitor and the third capacitor are for dividing the voltage of the electric field signal.

4. The wireless charging device according to claim 2 or 3, wherein the rectifying circuit comprises: A first diode, having a first terminal and a second terminal, wherein the first terminal of the first diode is coupled to the second terminal of the first capacitor, and the second terminal of the first diode is coupled to the output terminal of the rectifier circuit; A second diode, having a first terminal and a second terminal, wherein the first terminal of the second diode is coupled to the second terminal of the second capacitor, and the second terminal of the second diode is coupled to the output terminal of the rectifier circuit; A third diode, having a first terminal and a second terminal, wherein the first terminal of the third diode is coupled to a ground terminal, and the second terminal of the third diode is coupled to the second terminal of the first capacitor; and A fourth diode, having a first terminal and a second terminal, wherein the first terminal of the fourth diode is coupled to the ground terminal, and the second terminal of the fourth diode is coupled to the second terminal of the second capacitor; The first diode, the second diode, the third diode, and the fourth diode are configured to rectify the electric field signal to generate the DC signal.

5. The wireless charging device according to claim 4, wherein the rectifier circuit further comprises: A first inductor, having a first terminal and a second terminal, wherein the first terminal of the first inductor is coupled to the second terminal of the first capacitor, and the second terminal of the first inductor is coupled to the first terminal of the first diode; and A second inductor, having a first terminal and a second terminal, wherein the first terminal of the second inductor is coupled to the second terminal of the second capacitor, and the second terminal of the second inductor is coupled to the first terminal of the second diode; wherein the first inductor and the second inductor are configured to increase the conduction angle of the electric field signal to the first diode, the second diode, the third diode, and the fourth diode.

6. The wireless charging device according to claim 1, wherein the charging path control circuit further comprises: A first resistor, having a first terminal and a second terminal, wherein the first terminal of the first resistor is coupled to the first terminal of the second transistor, and the second terminal of the first resistor is coupled to the control terminal of the second transistor.

7. The wireless charging device according to claim 1, wherein the control driver includes: A third transistor, having a first terminal, a second terminal, and a control terminal, wherein the first terminal of the third transistor is coupled to the control terminal of the second transistor, the second terminal of the third transistor is coupled to the ground terminal, and the control terminal of the third transistor is coupled to the first terminal of the first transistor.

8. The wireless charging device according to claim 1, wherein the charging path control circuit further comprises: A second resistor, having a first terminal and a second terminal, wherein the first terminal of the second resistor is coupled to the control terminal of the first transistor, and the second terminal of the second resistor is coupled to the second terminal of the first transistor.

9. The wireless charging device according to claim 1, wherein: The first transistor is a metal-oxide-semiconductor field-effect transistor or a bipolar transistor; and The second transistor is a metal-oxide-semiconductor field-effect transistor or a bipolar transistor.

10. The wireless charging device according to claim 1 further includes an electric field detection circuit for generating a charging detection signal based on the DC signal, wherein the charging detection signal is related to the voltage magnitude of the DC signal, and the near field communication controller generates the charging control signal at least based on the charging detection signal.

11. The wireless charging device according to claim 10, wherein the electric field detection circuit includes: A filter clamping unit for filtering the DC signal to generate an electric field reference signal; And A voltage dividing unit for generating the charging detection signal by dividing the voltage of the electric field reference signal.

12. The wireless charging device according to claim 11, wherein the filter clamping unit includes: A third resistor having a first end and a second end, the first end of the third resistor for receiving the DC signal; A fourth capacitor having a first end and a second end, the first end of the fourth capacitor coupled to the second end of the third resistor and for outputting the electric field reference signal, and the second end of the fourth capacitor coupled to the ground terminal; And A first clamping diode having a first end and a second end, the first end of the first clamping diode coupled to the first end of the fourth capacitor, and the second end of the first clamping diode coupled to the second end of the fourth capacitor.

13. The wireless charging device according to claim 11 or 12, wherein the voltage dividing unit includes: A fourth resistor having a first end and a second end, the first end of the fourth resistor for receiving the electric field reference signal; A fifth resistor having a first end and a second end, the first end of the fifth resistor coupled to the second end of the fourth resistor and for outputting the charging detection signal, and the second end of the fifth resistor coupled to the ground terminal.

14. The wireless charging device according to claim 1, wherein the overvoltage protection circuit includes: A first voltage dividing component having a first end and a second end, the first end of the first voltage dividing component for receiving the DC signal; A second voltage dividing component having a first end and a second end, the first end of the second voltage dividing component coupled to the second end of the first voltage dividing component, and the second end of the second voltage dividing component coupled to the ground terminal; A sixth resistor having a first end and a second end, the first end of the sixth resistor for receiving the DC signal; A fourth transistor having a first end, a second end and a control end, the first end of the fourth transistor coupled to the second end of the sixth resistor, the second end of the fourth transistor coupled to the ground terminal, and the control end of the fourth transistor coupled to the second end of the first voltage dividing component; And A second clamping diode having a first end and a second end, the first end of the second clamping diode for receiving the DC signal, and the second end of the second clamping diode coupled to the ground terminal; Wherein: The first voltage dividing component and the second voltage dividing component are used for dividing the voltage of the DC signal to generate an overvoltage reference signal; and The fourth transistor is configured to turn on a pressure relief path formed by the fourth transistor and the sixth resistor according to the overvoltage reference signal to reduce the voltage value of the DC signal.

15. The wireless charging device according to claim 14, wherein the fourth transistor operates in the linear region to control the conduction degree of the pressure relief path according to the magnitude of the overvoltage reference signal.

16. The wireless charging device according to claim 14, wherein: The first voltage dividing component is a resistor or a clamping diode; and The second voltage dividing component is a resistor.

17. The wireless charging device according to claim 14, wherein the overvoltage protection circuit further includes: A third voltage dividing component having a first end and a second end, the first end of the third voltage dividing component is configured to receive the DC signal, and the second end of the third voltage dividing component is configured to output an overvoltage detection signal; and A fourth voltage dividing component having a first end and a second end, the first end of the fourth voltage dividing component is coupled to the second end of the third voltage dividing component, and the second end of the fourth voltage dividing component is coupled to the ground terminal; Wherein the near field communication controller generates the charging control signal at least according to the overvoltage detection signal.

18. The wireless charging device according to claim 17, wherein: The third voltage dividing component is a resistor or a clamping diode; and The fourth voltage dividing component is a resistor.

19. The wireless charging device according to claim 1, wherein: When the near field communication controller stops generating the near field communication signal, the near field communication controller generates the charging control signal to turn on the charging path by the charging path control circuit and increase the impedance of the matching filter circuit; Or When the near field communication controller generates the near field communication signal and transmits the near field communication signal through the matching filter circuit and the antenna, the near field communication controller generates the charging control signal to cut off the charging path by the charging path control circuit and reduce the impedance of the matching filter circuit.

20. The wireless charging device according to claim 1, further comprising a power management circuit coupled to the battery management circuit, wherein: The battery management circuit is further configured to output a supply power to the power management circuit according to the DC signal; and The power management circuit is configured to provide the power required by the near field communication controller according to the supply power.

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