Wireless charging system with multiple communication modes

Abstract

The invention relates to a wireless charging system with multiple communication modes. A wireless power transmission system has a wireless power receiving device that can be charged using a plurality of different types of wireless power transmission devices. Different types of wireless power transmitting devices have power transmitting coils that exhibit different levels of magnetic coupling from the power receiving coils of the wireless power receiving device. The wireless power receiving device may include capacitors, resistors, and / or other load circuits that may be independently switched into use according to the detected magnetic coupling level, according to the rectified voltage level, according to the magnitude of the output load, and / or according to information communicated during a handshake operation, the power receiving coil is coupled to the power transmitting device to present a desired impedance adjustment at the power receiving coil such that a data signal can be appropriately transmitted between the power receiving device and the power transmitting device.

Description

[0001] This application is a divisional application of the invention patent application with international application number PCT / US2019 / 042169, international application date July 17, 2019, application number 201980050867.9, and invention name “Wireless Charging System with Multiple Communication Modes”, which entered the Chinese national phase on January 29, 2021.

[0002] This application claims priority to U.S. Patent Application No. 16 / 196,975, filed on November 20, 2018, and U.S. Provisional Patent Application No. 62 / 715,167, filed on August 6, 2018, which are hereby incorporated by reference in their entirety. Technical Field

[0003] The present invention relates generally to wireless systems and, more particularly, to systems in which devices are charged wirelessly. Background Art

[0004] In a wireless charging system, a wireless power transmitting device, such as a device with a charging surface, wirelessly transmits power to a wireless power receiving device, such as a portable electronic device. The portable electronic device receives the wirelessly transmitted power and uses the power to charge an internal battery or power the device.

[0005] Sometimes it may be desirable to transmit data from a wireless power receiving device to a wireless power transmitting device. So-called "in-band" communication schemes have been developed that allow a wireless power receiving device to communicate with a wireless power transmitting device. In a typical in-band communication scheme, a switching circuit coupled to a coil in the wireless power receiving device is used to modulate a load across the coil. The wireless power transmitting device will attempt to detect the modulated signal using a sensing circuit coupled to the coil in the wireless power transmitting device.

[0006] Sometimes, however, changing the load across the coil at the wireless power receiving device does not necessarily translate into a sufficiently detectable amplitude or phase change at the sensing circuitry of the wireless power transmitting device. Summary of the invention

[0007] A wireless power transmission system has a wireless power receiving device that can be charged using a first wireless power transmission device having a first coil configuration or a second wireless power transmission device having a second coil configuration different from the first coil configuration. The wireless power receiving device may include a wireless power receiving coil, a wireless power receiving circuit coupled to the wireless power receiving coil, and a control circuit that can be operated to perform the following operations: (1) when a first magnetic coupling coefficient exists between the wireless power receiving coil and the first coil configuration of the first wireless power transmission device, configure the wireless power receiving device in a first data communication (or transmission) mode, and (2) when a second magnetic coupling coefficient exists between the wireless power receiving coil and the second coil configuration of the second wireless power transmission device, configure the wireless power receiving device in a second data communication (or transmission) mode.

[0008] The wireless power receiving device may also include a first switched capacitor (or resistor) coupled to the first end of the wireless power receiving coil and a second switched capacitor (or resistor) also coupled to the first end of the coil. The first switched capacitor is selectively activated only during the first data communication mode and not during the second data communication mode. The second switched capacitor is selectively activated only during the second data communication mode and not during the first data communication mode. There is no switched capacitor coupled to the second end of the wireless power receiving coil. The first switched capacitor has a significantly different capacitance value from the second switched capacitor. The wireless power receiving device may also include a rectifier circuit coupled to the wireless power receiving circuit. The rectifier circuit is operable in a full-bridge rectifier mode during the first data communication mode and is operable in a half-bridge rectifier mode during the second data communication mode.

[0009] The control circuit may determine whether to configure the wireless power receiving device in the first data communication mode or the second data communication mode during the handshake operation. During the handshake, the control circuit may initially configure the wireless power receiving device in the first data communication mode. In response to performing a successful handshake, the control circuit may then allow the wireless power receiving device to continue operating in the first data communication mode. However, in response to performing an unsuccessful handshake, the control circuit may reconfigure the wireless power receiving device in the second data communication mode and retry the handshake.

[0010] According to another suitable arrangement, the wireless power receiving device may include an adjustable capacitor group (e.g., a capacitor array) coupled to the coil and a control circuit, the control circuit being operable to configure the wireless power receiving device in a first data communication mode by activating at least a first portion of the capacitors in the adjustable capacitor group, and to configure the wireless power receiving device in a second data communication mode by activating at least a second portion of the capacitors in the adjustable capacitor group. The control circuit may dynamically adjust the adjustable capacitor group to ensure that sufficient signal strength is maintained between the wireless power receiving device and the wireless power transmitting device. The control circuit may be configured to adjust the capacitor group based at least in part on a rectified voltage output from a rectifier circuit, based on a load size driven by the rectifier circuit, based on a type of wireless power transmitting device, and / or based on a communication protocol specified by the power transmitting device. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 is a schematic diagram of an exemplary wireless charging system according to an embodiment.

[0012] Figure 2 is a circuit diagram of an exemplary wireless charging system according to an embodiment.

[0013] Figure 3 is a circuit diagram of an exemplary wireless power receiving device having the same capacitor selectively coupled to two terminals of a wireless power receiving coil when transmitting data to the wireless power transmitting device according to an embodiment.

[0014] Figure 4 is a circuit diagram of an exemplary wireless power receiving device having a capacitor of varying value that is selectively coupled to only one terminal of a wireless power receiving coil when transmitting data to the wireless power transmitting device according to an embodiment.

[0015] Figure 5 is operable according to an embodiment of the invention Figure 4 Schematic diagram of various wireless in-band communication modes for a wireless power receiving device of the type shown.

[0016] Figure 6 According to the implementation scheme, Figure 4 Flowchart of illustrative steps for configuring a wireless power receiving device of the type shown for appropriate data transmission.

[0017] Figure 7 is a circuit diagram of an illustrative wireless power receiving device with a capacitor bank that can be configured to support different types of wireless power transmitting devices according to an embodiment.

[0018] FIG. 8A to FIG. 8Dis a schematic diagram of different exemplary receiver tuning topologies that may be implemented at a wireless power receiving device according to some embodiments.

[0019] Fig. 9 is operable according to an embodiment of the invention Figure 7 Schematic diagram of various wireless in-band communication modes for a wireless power receiving device of the type shown.

[0020] Fig.10 According to the implementation scheme, Figure 7 Flowchart of illustrative steps for configuring a wireless power receiving device of the type shown for appropriate data transmission.

[0021] Fig.11 It is available for use according to the implementation scheme Figure 7 A schematic diagram of an illustrative resistor bank for a wireless power receiving device of the type shown.

[0022] Fig.12 is a schematic diagram of an illustrative load bank having both capacitors and resistors according to an embodiment. DETAILED DESCRIPTION

[0023] The wireless power system has a wireless power transmission device that wirelessly transmits power to a wireless power receiving device. The wireless power transmission device has one or more coils used in transmitting wireless power to one or more wireless power receiving coils in the wireless power receiving device. During operation, the wireless power transmission device provides an AC signal to one or more wireless power transmission coils. This causes the coil to transmit an AC electromagnetic signal (sometimes referred to as a wireless power signal) to one or more corresponding coils in the wireless power receiving device. A rectifier circuit in the wireless power receiving device converts the received wireless power signal into direct current (DC) power for powering the wireless power receiving device.

[0024] Figure 1 An exemplary wireless power system (wireless charging system) is shown in FIG. Figure 1 As shown, the wireless power system 8 includes a wireless power transmission device 12 and one or more wireless power receiving devices, such as a wireless power receiving device 10. Device 10 is a portable electronic device, such as a wristwatch, a cellular phone, a media player, a pair of earbuds, a remote control, a tablet computer, a laptop computer, an electronic stylus, a pen or pencil, or other electronic device. Device 12 can be a stand-alone device, such as a wireless charging pad, a wireless charging plate, a wireless charging stand, a wireless charging station, a desktop computer, a laptop computer, a tablet computer, or other suitable wireless charging device.

[0025] Devices 12 and 10 include control circuits 42 and 20, respectively. Control circuits 42 and 20 include storage and processing circuits, such as a microprocessor, a power management unit, a baseband processor, a digital signal processor, a microcontroller, and / or an application-specific integrated circuit with processing circuits. Control circuits 42 and 20 are configured to execute instructions for implementing desired control and communication features in system 8. For example, control circuits 42 and / or 20 may be used to determine power transfer levels, process sensor data, process user input, process other information from transmission circuits 34 such as information about wireless coupling efficiency, process information from receiving circuits 46, use information from circuits 34 and / or 46, such as signal measurements on output circuits in circuits 34 and other information from circuits 34 and / or 46, to determine when to start and stop wireless charging operations, adjust charging parameters such as charging frequency, coil alignment in a multi-coil array, and wireless power transfer levels, and perform other control functions.

[0026] The control circuit 42 and / or 20 may be configured to perform these operations using hardware (e.g., dedicated hardware or circuits) and / or software (e.g., code running on the hardware of the system 8). The software code for performing these operations is stored on a non-transitory computer-readable storage medium (e.g., a tangible computer-readable storage medium). The software code may sometimes be referred to as software, data, program instructions, instructions, or code. The non-transitory computer-readable storage medium may include non-volatile memory such as non-volatile random access memory (NVRAM), one or more hard disk drives (e.g., a disk drive or a solid-state drive), one or more removable flash drives or other removable media, other computer-readable media, or a combination of these computer-readable media or other storage. The software stored on the non-transitory computer-readable storage medium may be executed on the processing circuit of the control circuit 42 and / or 20. The processing circuit may include a dedicated integrated circuit having a processing circuit, one or more microprocessors, or other processing circuits.

[0027] During operation of system 8, a user places one or more devices 10 on the charging surface of device 12. Device 10 may also be otherwise attached or mounted to device 12 during wireless charging operation. Power transmission device 12 is optionally coupled to an AC voltage source, such as AC power source 50 (e.g., a wall outlet supplying line power or other mains power), has a battery such as battery 38 for powering, and / or is coupled to another power source. A power converter such as AC-DC power converter 40 may convert power from the mains or other AC power source to DC power for powering control circuitry 42 and other circuits in device 12. During operation, control circuitry 42 transmits an AC electromagnetic signal 48 to device 10 using wireless power transmission circuitry 34 and one or more coils 36 coupled to circuitry 34, thereby transmitting wireless power to wireless power receiving circuitry 46 of device 10. Therefore, coil 36 is sometimes referred to as a wireless power transmission coil or a wireless power transfer coil. In general, device 12 may have any suitable number of coils 36 (e.g., 1-100 coils, 5-25 coils, more than 100 coils, more than 5 coils, more than 10 coils, less than 40 coils, less than 30 coils, etc.), and device 10 may have any suitable number of coils 14.

[0028] The wireless power transmission circuit 34 has a switching circuit (e.g., a transistor in an inverter circuit) that is turned on and off based on a control signal provided by the control circuit 42 to generate an AC current signal through the appropriate coil 36. When the AC current passes through the coil 36 driven by the inverter circuit, an AC electromagnetic field (wireless power signal 48) is generated that is received by one or more corresponding coils 14 coupled to the wireless power receiving circuit 46 in the receiving device 10. When the AC electromagnetic field is received by the coil 14, a corresponding AC current and voltage are induced in the coil 14.

[0029] Rectifier circuit 80, sometimes considered to be part of circuitry 46, converts AC signals received from one or more coils 14 (e.g., received alternating current and voltage associated with wireless power signal 48) into DC voltage signals for powering device 10. The DC voltage is used to power components in device 10, such as sensors 54 (e.g., accelerometers, force sensors, temperature sensors, light sensors, pressure sensors, gas sensors, humidity sensors, magnetic sensors, etc.), wireless communication circuitry 56 for wireless communication with control circuitry 42 and / or other equipment of device 12, audio components, and other components (e.g., input-output devices 22 and / or control circuitry 20), and for charging internal batteries such as battery 18 in device 10.

[0030] Device 12 and / or device 10 may communicate wirelessly. Devices 10 and 12 may, for example, have wireless transceiver circuits in control circuits 42 and 20 (and / or wireless communication circuits such as circuit 56) to allow wireless transmission of signals between devices 10 and 12 (e.g., transmitting and receiving one-way or two-way wireless signals using an antenna separate from coils 36 and 14, transmitting and receiving one-way or two-way wireless signals using coils 36 and 14, etc.).

[0031] When it is desired to transmit data from device 12 to device 10, data transmitter circuit 100 in control circuit 42 may be used to modulate the signal supplied to coil 36. Control circuit 20 of power receiving device 10 may use data receiver circuitry such as data receiver 104 to demodulate the modulated signal pulses from transmitter 100. Conversely, data transmitter circuit 106 of device 10 may be used to generate the signal transmitted by coil 14 to coil 36 of device 12 and demodulated by data receiver 102 in control circuit 42 of device 12.

[0032] When it is desired to transmit data from device 10 to device 12, device 12 may optionally suspend power transmission. When device 12 is not transmitting wireless power to device 10, data transmitter circuit 106 of device 10 may modulate one or more transistors in wireless power receiving circuit 46 or control circuit 20 to generate a wireless signal transmitted from coil 14 of device 12 to coil 36. Because the data signal is wirelessly transmitted from device 10 to device 12 using coils 14 and 36, this type of data communication between device 10 and device 12 may sometimes be referred to as "in-band" communication. Device 12 may use data receiver 20 to demodulate the wireless signal from device 10, thereby receiving data transmitted from device 10. The transmitted data may be used to implement communication between device 10 and device 12, such as supplying feedback or other control signals to device 12, or may be used to transmit other information. This example of temporarily suspending power transmission during data transmission is merely illustrative. If desired, wireless power transmission and data reception may occur simultaneously (without suspending power transmission).

[0033] When device 12 is in the power transfer mode, control circuitry 42 may modulate the AC drive signal being supplied to the output inverter transistor coupled to coil 36 using pulse width modulation (PWM) to regulate how much power is supplied to device 10. For example, the duty cycle of the PWM pulse train may be dynamically adjusted to regulate the amount of power wirelessly transferred from device 12 to device 10. If desired, the duty cycle of the PWM pulses may be adjusted based on power transfer feedback information communicated in-band from data transmitter 106 to data receiver 102. For example, device 12 may use information that has been transmitted back from device 10 to device 12 to increase or decrease the amount of transfer power that device 12 provides to device 10.

[0034] The output inverter transistor in the wireless power transmission circuit 34 is modulated to generate an AC output waveform signal suitable for driving the coil 36 for wireless power transmission. In some examples, the frequency of the signal is in the kilohertz range, such as between 100kHz and 400kHz, including in particular frequencies in the range of 125kHz to 130kHz. In some examples, the signal is in the megahertz range, such as about 6.78MHz, or more generally between 1MHz and 100MHz. In some examples, the signal is in the gigahertz range, such as about 60GHz, and more generally between 1GHz and 100GHz. When the AC signal passes through the coil 36, a corresponding wireless power signal (electromagnetic signal 48) is generated and transmitted to the coil 14 of the device 10. The present AC frequency of the modulated power transmission circuit 34 is sometimes referred to as the power carrier frequency. The data signal received at the receiver 102 can be modulated at a lower frequency. The modulation frequency at which data is transmitted from the device 10 to the device 12 is sometimes referred to as the "data rate". For example, when transmitting power in the 100 kHz range, the data rate may be 2 kHz, 1-10 kHz, 10-50 kHz, less than 100 kHz, less than 80 kHz, less than 50 kHz, or other suitable frequencies above or below 2 kHz.

[0035] Figure 2 A circuit diagram of an exemplary circuit for a wireless power transfer (wireless power charging) system 8 is shown in FIG. Figure 2 As shown, the wireless power receiving device 10 can be charged using the first power transmission device 12-1 or the second power transmission device 12-2. Each of the first wireless power transmission device 12-1 and the second wireless power transmission device 12-2 includes a wireless power transmission circuit 34 having an inverter (such as inverter 70) or other drive circuits that generate AC drive signals (such as variable duty cycle square waves or other drive signals). These signals are driven through output circuits, such as output circuits 68 including coils 36 and capacitors 72, to generate wireless power signals that are wirelessly transmitted to the device 10.

[0036] Control circuitry 42 in each of devices 12-1 and 12-2 may also include wireless transceiver circuitry (e.g., a wireless transceiver circuit) for supporting wireless data transmission between devices 10 and 12 (i.e., device 12-1 or 12-2). Figure 1 In the device 10, the wireless transceiver circuit in the control circuit 20 (e.g., Figure 1104 and data transmitter 106) can transmit data to device 12-1 or device 12-2 using path 88 and coil 14. In each of device 12-1 and device 12-2, a path such as path 74 can be used to supply an incoming data signal that has been received from device 10 using coil 36 to a circuit in a data receiver of demodulation (receiver) control circuit 42. If desired, path 74 can also be used to transmit wireless data to device 10 using coil 36, which is received by a data receiver of circuit 20 using coil 14 and path 88.

[0037] During wireless power transfer operation, the transistors in the inverter 70 are controlled using AC control signals generated by the control circuit 42. The control circuit 42 supplies control signals to the gates of the transistors in the inverter 70 using the control path 76. The duty cycle and / or other properties of these control signals and thus the corresponding characteristics of the drive signals applied to the coils 36 by the inverter 70 and the corresponding wireless power signals generated by the coils 36 can be dynamically adjusted. Using the switching circuit, the control circuit 42 selects which coil or coils to supply the drive signal. Using duty cycle adjustment and / or other adjustments (e.g., drive frequency adjustment, etc.), the control circuit 42 can adjust the strength of the drive signal applied to each coil.

[0038] The wireless power receiving device 10 has a wireless power receiving circuit 46. The circuit 46 includes a rectifier circuit such as a rectifier 80 (e.g., a synchronous rectifier controlled by a signal from the control circuit 20) to convert an AC signal received from the coil 14 (e.g., a wireless power signal received by the coil 14) into a direct current (DC) power signal for powering circuits in the device 10 such as a load 82 (sometimes referred to as an output load). Load circuits such as load 82 may include a battery 18, a power circuit that receives power from the rectifier circuit 80 and regulates the flow of power to the battery 18, such as a battery charging integrated circuit or other power management integrated circuit, and / or other input-output devices 22 ( Figure 1 ).like Figure 2 As shown, one or more capacitors Crx and Crx' are used to couple the coil 14 in the input circuit 90 of the device 10 to the input terminal of the rectifier circuit 80. The coupling capacitor Crx' is optional. The rectifier circuit 80 generates a corresponding output power at the output terminal coupled to the load 82. If desired, the load 82 may include sensor circuits (e.g., current sensors and voltage sensors) for monitoring the power flow from the rectifier 80 to the load 82.

[0039] The ability of device 10 to communicate with or be charged by device 12 may depend on the inductive (or magnetic) coupling between coils 14 and 36. The amount of magnetic coupling between coils 14 and 36 may depend on the number of coils 36, the number of active coils 36 (e.g., control circuitry 42 may use multiplexing circuitry to switch a portion of coils 36 into use while disabling another portion of coils 36), the amount of overlap between coils 36, the orientation of coils 36 relative to coil 14, the windings of coils 14 and 36, or other physical properties associated with coils 14 and 36.

[0040] exist Figure 2 In the example of , power transfer device 12-1 has coil 36-1 of a first configuration, and power transfer device 12-2 has coil 36-2 of a second configuration different from the first coil configuration. In other words, the physical arrangement and / or number of coils between devices 12-1 and 12-2 may be different. Thus, when device 10 is charged using device 12-1, there may be a first amount of magnetic coupling between device 12-1 and device 10 (as indicated by a first coupling coefficient k1), and when device 10 is charged using device 12-2, there may be a second amount of magnetic coupling between device 12-2 and device 10 (as indicated by a second coupling coefficient k2). Coefficients k1 and k2 are sometimes referred to as magnetic coupling coefficients, electromagnetic coupling coefficients, or inductive coupling coefficients.

[0041] As described above, data transmitter circuitry, such as data transmitter 106 in control circuitry 20 of device 10, may be configured to modulate one or more transistors in wireless power receiving circuitry 46 to transmit an "in-band" data signal from coil 14 to coil 36 of device 12 (e.g., device 10 modulates the data to be transmitted by changing the impedance at coil 14). Device 12 may be configured to decode the corresponding data by sensing a perturbation in the waveform based on the impedance change at coil 14. In general, any suitable modulation scheme may be used to support transmission of data signals from device 10 to device 12. For example, transmitter 106 may modulate the transmitted data using a modulation scheme such as amplitude shift keying (ASK) modulation.

[0042] Conventionally, the data transmitter at device 10 is capable of generating only a step change in load current. For example, the data transmitter includes only a pair of capacitors with equal capacitance for adjusting the impedance at coil 14. Assuming that the coupling coefficient k1 is large enough to cause a sufficiently detectable disturbance at coil 36-1, modulating the data by switching a pair of capacitors in and out of use can produce a satisfactory response at device 12-1. If the coupling coefficient k2 is substantially similar to the coupling coefficient k1 (for example, if k2 deviates from k1 by less than 1% of k1, less than 5% of k1, less than 10% of k1, less than 20% of k1, etc.), then the device 10 configured in this manner may also be able to properly transmit the data signal to device 12-2. In the case where the coupling coefficient k2 is significantly different from the coupling coefficient k1 (for example, if k2 deviates from k1 by more than 20% of k1, more than 30% of k1, more than 50% of k1, more than 100% of k1, etc.), if the coupling coefficient k2 is too small to cause a sufficiently detectable disturbance at coil 36-2, then modulating data by switching the same pair of identical capacitors into use and out of use will risk not producing a satisfactory response at device 12-2.

[0043] In order to enable device 10 to effectively communicate with two or more power transfer devices that exhibit different coupling coefficients or different magnetic coupling levels with coil 14, device 10 may be configured with at least two different capacitor groups, wherein a first group of capacitors generates a first step load (or impedance) change suitable for communicating with device 12-1 during a first charging mode, and wherein a second group of capacitors generates a second step load (or impedance) change suitable for communicating with device 12-2 during a second charging mode.

[0044] Figure 3 is a circuit diagram of an exemplary wireless power receiving device 10, which is configured with at least two sets of capacitors for modulating the impedance at the coil 14 to transmit the data signal back to the wireless power transmitting device. Figure 3 As shown, the first capacitor Cx1 has a first terminal coupled to a node 302 and a second terminal coupled to a switch Q1, the node 302 connecting the capacitor Crx to the rectifier circuit 80. The second capacitor Cx2 has a first terminal coupled to a node 304 and a second terminal coupled to a switch Q2, the node 304 connecting the capacitor Crx' to the rectifier circuit 80. The capacitor Crx' may be optional. If the capacitor Crx' is omitted, the node 304 will be directly connected to the coil 14. The capacitors Cx1 and Cx2 and the switches Q1 and Q2 can be considered as data transmitters 106 ( Figure 1 ), is considered to be separate from the data transmitter 106 but part of the control circuit 20, or is considered to be part of the wireless power receiving circuit 46.

[0045] Switches Q1 and Q2 may be implemented as complementary metal oxide semiconductor (CMOS) transistors, bipolar junction transistors (BJTs), microelectromechanical systems (MEMS) switches, or other suitable types of electronic switches. Transistors Q1 and Q2 may have source terminals connected to a ground power line and gate terminals that receive a first control signal Vcom1 from the control circuit 20. Configured in this manner, the control circuit 20 may switch Vcom1 to modulate transistors Q1 and Q2, thereby simultaneously switching capacitors Cx1 and Cx2 into use to affect a first impedance change at the coil 14. Since capacitors Cx1 and Cx2 are simultaneously switched on and off across the two terminals of the coil 14, the capacitance values ​​of Cx1 and Cx2 should be equal (e.g., capacitors Cx1 and Cx2 are equal in size and should be symmetrically coupled to the two ends of the coil 14).

[0046] Modulating the data communication signal Vcom1 to switch the first set of capacitors Cx1 and Cx2 into use may be suitable for transmitting the data signal to the device 12-1 (e.g., capacitors Cx1 and Cx2 are designed to operate efficiently with a coupling coefficient k1). Generally, if the magnetic coupling coefficient is small, a larger switching capacitance is required at the coil 14 to achieve a desired amount of response at the coil 36. On the other hand, if the magnetic coupling coefficient is large, a smaller switching capacitance is required at the coil 14 to produce a detectable response at the coil 36.

[0047] Still see Figure 3 , the third capacitor Cy1 has a first terminal coupled to the node 302 and a second terminal coupled to the switch Q3. The fourth capacitor Cy2 has a first terminal coupled to the node 304 and a second terminal coupled to the switch Q4. The capacitors Cy1 and Cy2 and the switches Q3 and Q4 can be considered as the data transmitter 106 ( Figure 1 ), considered separate from the data transmitter 106 but part of the control circuit 20, or considered part of the wireless power receiving circuit 46. Switches Q3 and Q4 may be implemented as complementary metal oxide semiconductor (CMOS) transistors, bipolar junction transistors (BJTs), micro-electromechanical systems (MEMS) switches, or other suitable types of electronic switches.

[0048] Transistors Q3 and Q4 may have source terminals connected to a ground terminal and a gate terminal that receives a second control signal Vcom2 from the control circuit 20. Configured in this manner, the control circuit 20 may switch the signal Vcom2 to modulate transistors Q3 and Q4, thereby simultaneously switching capacitors Cy1 and Cy2 into use to affect a second impedance change at the coil 14. Since capacitors Cy1 and Cy2 are simultaneously switched on and off across nodes 302 and 304, the capacitance values ​​of Cy1 and Cy2 should be equal (e.g., capacitors Cy1 and Cy2 have the same size and should be symmetrically coupled to both ends of the coil 14).

[0049] Modulating the data communication signal Vcom2 to switch the second set of capacitors Cy1 and Cy2 into use may be suitable for transmitting the data signal to the device 12-2 (e.g., capacitors Cy1 and Cy2 are designed to operate efficiently with a coupling coefficient k2). Assuming that the coefficients k1 and k2 are significantly different, the capacitances of Cx1 and Cx2 should also be different from the capacitances of Cy1 and Cy2. For example, if the coupling coefficient k1 is greater than the coefficient k2, the capacitances of Cx1 and Cx2 should be less than the capacitances of Cy1 and Cy2. For another example, if the coupling coefficient k1 is less than the coefficient k2, the capacitances of Cx1 and Cx2 should be greater than the capacitances of Cy1 and Cy2.

[0050] If desired, the capacitors (e.g., Cx1, Cx2, Cy1, and Cy2) may be replaced with resistors, combinations of resistive and capacitive circuits connected in any series or parallel configuration, or other passive electronic components suitable for achieving the desired amount of impedance change at the wireless power receiving coil 14. The rectifier circuit 80 may be configured as a full-bridge or half-bridge rectifier, depending on the output voltage requirements at the load 82. The two different sets of capacitors may be independently modulated according to the perceived coupling coefficient. Figure 3 The examples of are merely illustrative. If desired, additional capacitor banks or capacitor pairs may be included to enable device 10 to communicate with any number of wireless power transfer devices having different coupling coefficients.

[0051] exist Figure 3 In the example of FIG. 1 , device 10 requires four switched capacitors Cx1, Cx2, Cy1, and Cy2 to communicate in two different modes: (1) a first mode for transmitting data to device 12-1 via a first coupling coefficient k1, and (2) a second mode for transmitting data to device 12-2 via a significantly different second coupling coefficient k2. However, using four switched capacitors in this manner takes up valuable circuit area and increases the cost of device 10. To save cost, space, and energy, a switched capacitor may be coupled to only one end of coil 14 (see, e.g., FIG. 1 ). Figure 4 ).

[0052] like Figure 4 As shown, the first capacitor C1 has a first terminal coupled to a node 402 and a second terminal coupled to a switch 410, which node 402 connects the capacitor Crx to the rectifier circuit 80. The second capacitor C2 has a first terminal coupled to the node 402 and a second terminal coupled to the switch 412. The switches 410 and 412 can be implemented as complementary metal oxide semiconductor (CMOS) transistors, bipolar junction transistors (BJTs), micro-electromechanical systems (MEMS) switches, or other suitable types of electronic switches. The capacitors C1 and C2 and the switches 410 and 412 can be considered as data transmitters 106 ( Figure 1 ), is considered to be separate from the data transmitter 106 but part of the control circuit 20, or is considered to be part of the wireless power receiving circuit 46.

[0053] The switch 410 has a gate terminal for receiving a first communication control signal Vcom1 from the control circuit 20, and the switch 412 has a gate terminal for receiving a second communication control signal Vcom2 from the control circuit 20. The control circuit 20 may modulate the signal Vcom1 when communicating with the power transmission device 12-1, or modulate the signal Vcom2 when communicating with the power transmission device 12-2. Modulating the data communication signal Vcom1 to switch the capacitor C1 into use may be applicable to transmitting the data signal to the device 12-1 (e.g., the capacitor C1 is designed to operate efficiently with a coupling coefficient k1). Alternatively, modulating the data communication signal Vcom2 to switch the capacitor C2 into use may be applicable to transmitting the data signal to the device 12-2 (e.g., the capacitor C2 is designed to operate efficiently with a coupling coefficient k2).

[0054] Assuming that the coefficients k1 and k2 are significantly different, the capacitance of C1 should also be different from the capacitance of C2. For example, if the coupling coefficient k1 is greater than the coefficient k2, the capacitance of C1 should be less than the capacitance of C2. For another example, if the coupling coefficient k1 is less than the coefficient k2, the capacitance of C1 should be greater than the capacitance of C2. If desired, the signals Vcom1 and Vcom2 can be modulated simultaneously (e.g., to switch both capacitors C1 and C2 into use) to achieve a third step load or impedance change at coil 14 that is suitable for yet another coupling coefficient different from k1 or k2.

[0055] Thus, device 10 operates in two different data transfer modes (such as with Figure 3 The four capacitors and associated switches in the Figure 4The example of may help save area and reduce power consumption of device 10. If desired, switched capacitors C1 and C2 may be replaced with resistors, combinations of resistive and capacitive circuits connected in any series or parallel configuration, or other passive electronic components suitable for achieving the desired amount of impedance change at wireless power receiving coil 14. If desired, one or more additional switched capacitors may be connected to node 402 (as indicated by path 450) to enable device 10 to communicate with any number of wireless power transmission devices having different coupling coefficients, wherein each additional switched capacitor has a capacitance different from or equal to capacitor C1 or capacitor C2.

[0056] The rectifier circuit 80 can be operated as a full-bridge rectifier or a half-bridge rectifier, depending on the output voltage requirements at the load 82. Figure 4 As shown, the rectifier circuit 80 may include a first diode D1 having a first (p-type) terminal connected to the node 402 and a second (n-type) terminal connected to the load 82, a second diode D2 having a first (p-type) terminal connected to ground and a second (n-type) terminal connected to the node 402, a third diode D3 having a first (p-type) terminal connected to the node 404 (which is connected to the coil 14 via an optional coupling capacitor Crx') and a second (n-type) terminal connected to the load 82, and a fourth diode D4 having a first (p-type) terminal connected to ground and a second (n-type) terminal connected to the node 404. Note that no switched capacitors are coupled to the node 404 (i.e., switched capacitors such as C1 and C2 are coupled only to the node 402).

[0057] The mode of operating the rectifier circuit 80 should also depend on the coupling coefficient. When the device 10 is charged by the device 12 via a relatively low coupling coefficient k_low, a smaller AC signal will be sensed at the wireless power receiving circuit 46, which is more suitable for half-bridge rectification. In such cases, the switch 420 can be turned on to short-circuit the diode D4 (i.e., by directly grounding the node 404). Enabling the switch 420 also effectively disables the diode D3 because the p-type terminal of the diode D3 is fixed to the ground. On the other hand, when the device 10 is charged by the device 12 via a relatively high coupling coefficient k_high, a larger AC signal will be sensed at the wireless power receiving circuit 46, which is more suitable for full-bridge rectification. In this case, the switch 420 is disconnected, so that all diodes D1-D4 can be used for normal full-bridge rectification operation.

[0058] Figure 5 is shown in which the operation Figure 4 Schematic diagram of various wireless in-band communication modes for a device 10 of the type shown. Figure 5As shown, device 10 may operate in a first data communication mode 500. Mode 500 may be suitable for transmitting data to a corresponding wireless power transmission device having a large coupling coefficient k. During mode 500, capacitor C1 may be enabled by modulating switch 410, while capacitor C2 may be idle by keeping switch 412 closed (assuming capacitor C1 is smaller than C2). When the coupling coefficient is large, rectifier circuit 80 may be configured as a full-bridge rectifier (e.g., by disabling switch 420).

[0059] Device 10 may also operate in a second data communication mode 502. Mode 502 may be suitable for transmitting data to a corresponding wireless power transmission device having a small coupling coefficient k. During mode 502, capacitor C2 may be switched into use by modulating switch 412, while capacitor C1 may be switched out of use by keeping switch 410 idle (again assuming that capacitor C1 is smaller than C2). When the coupling coefficient is small, rectifier circuit 80 may be configured as a half-bridge rectifier (e.g., by activating switch 420).

[0060] Device 10 optionally operates in one or more additional data communication modes 504. Mode 504 may be suitable for transmitting data to a corresponding wireless power transfer device, wherein the coupling coefficient k has some other value than those covered by modes 500 and 502. During mode 504, some other combination of capacitors (or resistors) may be switched into use using one or more additional switches, and rectifier circuit 80 may be configured in full-bridge mode or half-bridge mode depending on the voltage requirements at load 82.

[0061] Figure 6 is used to Figure 4 A flow chart of illustrative steps for configuring a wireless power receiving device 10 of the type shown for appropriate data transmission. A user may first bring the power receiving device 10 into proximity with the power transmitting device 12. For example, the user may place the device 10 on a charging surface of the device 12, or may otherwise attach or mount the device 10 to the device 12.

[0062] At step 600, the power transmission device 12 may detect the power receiving device 10 and may attempt to perform a handshake with the power receiving device 10. Example handshaking operations that may be performed between the devices 10 and 12 may include performing device authentication (e.g., authenticating the device 10 to the device 12), detecting the power capabilities supported by the receiving device 10 (e.g., so that the power transmission device 12 may transmit power to the device 10 using the correct power setting), negotiating an appropriate power transfer level, and establishing a link for appropriate wireless power transfer from the device 12 to the device 10 and other handshaking protocols that may be required for appropriate wireless data transfer between the devices 10 and 12.

[0063] At step 602, the power receiving device 10 may attempt to use a first (default) communication mode (eg, Figure 5 The power receiving device 10 may then perform a handshake with the power delivery device 12 in the default communication mode 500. At step 604, the power receiving device 10 may determine whether a successful handshake has occurred. For example, a successful handshake operation may occur when the power receiving device 10 receives a handshake confirmation packet from the device 12. If the handshake is successful, no further mode change is required at the power receiving device 10 (e.g., the power receiving device 10 may continue to operate and transmit in-band data signals to the device 12 using the default communication mode 500), and the power delivery device 12 may transfer power to the power receiving device 10 (step 610).

[0064] If the handshake is unsuccessful, the power receiving device 10 may use another data communication mode (e.g., Figure 5 At step 606, device 10 may retry handshaking with power delivery device 12 using the new communication mode. Processing may loop back to step 604, as indicated by path 608. If the handshake between devices 10 and 12 is now successful, the new data communication mode now modulates the capacitor at a value more appropriate for the current coupling coefficient that exists between devices 10 and 12.

[0065] Figure 6 The steps for detecting the coupling coefficient and for selecting the desired communication mode suitable for the detected / sense coupling coefficient between devices 10 and 12 are merely illustrative and are not intended to limit the scope of embodiments of the present invention. If desired, device 12 may directly or actively transmit this information to device 10, or may otherwise guide device 10 to select the correct switched capacitor, device 10 may have a sensing circuit or monitoring circuit to measure the coupling coefficient or mutual inductance between the coils of devices 10 and 12, or may implement other suitable means for determining the optimal data transmission mode.

[0066] The wireless power receiving circuit 46 includes at least capacitors C1 and C2 for supporting Figure 5 Modes 500, 502 and 504 Figure 4 The examples are merely illustrative and are not intended to limit the scope of the embodiments of the present invention. According to another suitable embodiment, Figure 7 A wireless power receiving circuit 46 is shown configured with individually selectable capacitor banks, such as capacitor bank 450. Figure 4 Components within the wireless power receiving circuit 46 that are labeled with the same reference numerals as those already shown in FIG. 4 have the same structure and function and do not need to be described in detail again in order to avoid obscuring the embodiments of the present invention.

[0067] like Figure 7As shown, a capacitor bank 450 is coupled to a node 42 located between capacitor Crx and rectifier circuit 80. Bank 450 may include an array of capacitors C1, C2, C3, Cn, each of which may be individually switched into use. In general, "n" may represent any integer greater than or equal to 2. A small number of capacitors in bank 450 provides a coarse adjustment capability, while a large number of capacitors in bank 450 provides a finer adjustment capability. Capacitor C1 may be selectively activated by turning on a first switch using a first control signal V1; capacitor C2 may be selectively activated by turning on a second switch using a second control signal V2; capacitor C3 may be selectively activated by turning on a third switch using a third control signal V3; ...; and capacitor Cn may be selectively activated by turning on the nth switch using a control signal Vn. Control signals V1-Vn may be generated using control circuit 20. Control circuit 20 may enable one or more of control signals V1-Vn (e.g., may enable any subset or even all of the n capacitors). Therefore, bank 450 configured in this manner is sometimes referred to as a capacitor array.

[0068] In one suitable arrangement, the n capacitors in the capacitor group 450 can be scaled linearly. For example, consider a situation where the capacitor group includes three capacitors: a first capacitor C1 exhibiting a low capacitance suitable for a first operating mode, a second capacitor C2 exhibiting a medium capacitance suitable for a second operating mode, and a third capacitor C3 exhibiting a high capacitance suitable for a third operating mode. In this example, one selected from the three capacitors C1, C2, or C3 can be enabled according to the desired operating mode. This example of using a linear scale to set the size of the capacitors in the group 450 is merely illustrative. If desired, the n capacitors in the group 450 can be sized according to a binary scale, an exponential scale, or can have other suitable weighting schemes optimized for certain operating modes.

[0069] In general, the controller 20 may selectively activate any number of capacitors in the group 450 to adjust the signal strength of the data signal transmitted from the inductor 14 to the corresponding wireless power transmission device. Determining which capacitors in the group 450 to activate may depend on the rectified voltage output from the rectifier circuit 80 (e.g., a full-bridge rectifier circuit or a half-bridge rectifier circuit), may depend on the output load 82, and / or may depend on one or more system parameters received by the control circuit 20 at the input 464.

[0070] The control circuit 20 may receive information about the rectified voltage generated by the rectifier circuit 80, which is schematically represented by the feedback path 460. If the rectified voltage is low, the control circuit 20 may direct the group 450 to increase its total capacitance. If the rectified voltage is high (i.e., if the voltage fluctuations are too large), the control circuit 20 may direct the group to reduce its total capacitance.

[0071] The control circuit 20 may also receive information about the load 82, which is schematically represented by the feedback path 462. If the load is light, the control circuit 20 may direct the group 450 to increase its total capacitance to help increase the signal-to-noise ratio. If the load is heavy, the control circuit 20 may direct the group 450 to decrease its total capacitance to help reduce the risk of excessive voltage fluctuations at the output.

[0072] The control circuit 20 may also receive one or more system parameters associated with the device 12 and / or the device 10. For example, the received system parameters may indicate the transmitter type (i.e., the type of wireless power transmission device 12 currently communicating with the wireless power receiving circuit 46). For another example, the received system parameters may indicate the type of communication protocol currently used to support the transmission of messages between the circuit 46 and the corresponding transmitter device 12 (regardless of the coupling coefficient currently existing between the devices 10 and 12). For example, a first communication protocol may operate at a first frequency and have a first bit error rate (BER) standard, while a second communication protocol may operate at a second frequency and have a second BER standard.

[0073] Regardless of the type of information received at control circuitry 20, controller 20 may dynamically adjust group 450 to ensure that adequate signal strength is maintained between device 10 and device 12 throughout the communication process.

[0074] Figure 4 and Figure 7 The example of is merely illustrative, where the wireless power receiver circuit 46 has a series LC tuning topology (ie, the inductor 14 and the capacitor Crx are connected in series as a resonant circuit). In general, it can be extended Figure 4 and Figure 7 The wireless power receiver circuit 46 can support any receiver tuning architecture (see, e.g. FIG. 8A to FIG. 8D ). Fig. 8A An exemplary parallel LC tuning topology is shown in which an inductor 14 is coupled in parallel with a capacitor Crx. Figure 8B A first exemplary LCC tuning topology is shown in which an inductor 14 is connected in series with a capacitor Crx1 and in which another capacitor Crx2 is coupled in parallel with the series combination of the inductor 14 and Crx1. Figure 8C A second exemplary LCC tuning topology is shown in which an inductor 14 is connected in parallel with a capacitor Crx1 and in which another capacitor Crx2 is coupled in series with the parallel combination of the inductor 14 and Crx1. Fig.8D An exemplary LCL tuning topology is shown in which an inductor 14 is connected in parallel with a capacitor Crx, and in which another inductor Lrx is coupled in series with the parallel combination of inductor 14 and Crx. Other receiver tuning / resonant circuit topologies may also be implemented if desired.

[0075] Any number of capacitors in group 450 may be activated Figure 7 Examples of provide improved flexibility to support communications with a variety of transport and protocol types while maintaining adequate signal levels during data communications.

[0076] Fig. 9 It shows which operations can be performed Figure 7 Schematic diagram of various wireless in-band communication modes for a device 10 of the type shown. Fig. 9 As shown, the device 10 may operate in a first data communication mode 900. Mode 900 may be suitable for communicating with a first transmitter type, or for supporting a first communication protocol. During mode 900, a first set of capacitors in group 450 may be activated (e.g., a first subset or portion of capacitors in the array may be turned on) to ensure that signal strength is maintained at an acceptable level when the wireless power receiving circuit 46 is communicating with the first transmitter type or when supporting the first communication protocol.

[0077] The device 10 may also operate in a second data communication mode 902. The mode 902 may be suitable for communicating with a second transmitter type different from the first transmitter type, or for supporting a second communication protocol different from the first communication protocol. During mode 902, a second set of capacitors in the bank 450 may be activated (e.g., a second subset or portion of capacitors different from the first subset in the array may be turned on) to ensure that the signal strength is maintained at an acceptable level when the wireless power receiving circuit 46 is communicating with the second transmitter type or when supporting the second communication protocol.

[0078] The device 10 is optionally operable in one or more additional data communication modes 904. The modes 904 may be suitable for communicating with other transmitter types than the first / second transmitter types, or for supporting additional communication protocols other than the first / second communication protocols. During the mode 904, another set of capacitors in the group 450 may be activated (e.g., a third subset or portion of capacitors other than the first / second subset in the array may be turned on) to ensure that the signal strength is maintained at an acceptable level when the wireless power receiving circuit 46 is communicating with other transmitter types or when supporting additional communication protocols.

[0079] Fig.10 Is used for operation Figure 7 Flowchart of illustrative steps for a wireless power receiving device 42 of the type shown. A user may first bring a power receiving device 10 into proximity with a power transmitting device 12. For example, the user may place the device 10 on a charging surface of the device 12, or may otherwise attach or mount the device 10 to the device 12.

[0080] At step 1000, the power transmission device 12 may detect the power receiving device 10 and may attempt to perform a handshake with the power receiving device 10. During the handshake operation, the transmitting device 12 may transmit an outgoing packet including transmitter type information (e.g., control data indicating the type of device 12) and / or desired communication protocol information (e.g., control data reflecting a desired data rate, BER, or other signaling standard). Other exemplary handshake operations that may be performed at this time may include device authentication, negotiation of an appropriate power transfer level, etc.

[0081] At step 1002, the power receiving device 10 may receive a packet transmitted from the device 12 and may decode the received packet to identify the transmitter type and / or the required protocol. In response to determining the transmitter type and / or the required protocol, the receiving device 10 may place the wireless receiving circuit 46 into an available communication mode (see, e.g., FIG. 1 ) by switching to use one or more capacitors in the capacitor array 450 (at step 1004). Fig. 9 The selection of which capacitors in the array to enable may also be based on the rectified voltage level at the output of the rectifier circuit 80 and / or the size of the output load 82 (see Figure 7 ).

[0082] Once the selected capacitors have been activated, device 10 can communicate appropriately with device 12 while maintaining adequate signal strength. As device 10 and device 12 exchange data, operating conditions can potentially change. If so, controller 20 can optionally reconfigure capacitor bank 450 as needed to optimize data communication between devices 10 and 12 (step 1006).

[0083] In combination with an adjustable capacitor bank 450 for providing reactance (or imaginary impedance) modulation Figure 7 , Fig. 9 and Fig.10 The described embodiments are merely illustrative and are not intended to limit the scope of the embodiments of the present invention. According to another suitable embodiment, the wireless power receiving circuit 46 may alternatively use an adjustable resistor group such as Fig.11 The resistor group 451 can be configured to provide resistance (or impedance real part) modulation at the circuit 46. Fig.11 As shown, resistor group 451 may include an array of resistors R1, R2, R3, ..., Rm, each of which may be individually switched into use. In general, "m" may represent any integer greater than or equal to 2. A small number of resistors within group 451 provides a coarse adjustment capability, while a large number of resistors within group 451 provides a finer adjustment capability.

[0084] The resistor R1 can be selectively activated by turning on the first switch using the first control signal V1; the resistor R2 can be selectively activated by turning on the second switch using the second control signal V2; the resistor R3 can be selectively activated by turning on the third switch using the third control signal V3; ...; and the resistor Rm can be selectively activated by turning on the nth switch using the control signal Vn. The control signals V1-Vn can be generated using the control circuit 20 (see Figure 7 ). Control circuit 20 may validate one or more of control signals V1-Vn (e.g., may enable any subset or even all of the m resistors). Thus, group 450 configured in this manner is sometimes referred to as a resistor array. Similar to the capacitor example, the m resistors in group 451 may be sized according to a linear scale, a binary scale, an exponential scale, or may have other suitable weighting schemes optimized for certain operating modes.

[0085] In general, the controller 20 may selectively activate any number of resistors in the group 451 to adjust the signal strength of the data signal transmitted from the inductor 14 to the corresponding wireless power transmission device. Determining which resistors in the group 451 to activate may depend on the rectified voltage output from the rectifier circuit 80 (e.g., a full-bridge rectifier circuit or a half-bridge rectifier circuit), may depend on the size of the output load 82, and / or may depend on one or more of the above-mentioned system parameters.

[0086] If desired, the resistor group 451 may also be placed after the rectifier circuit 80 (e.g., Figure 7 402 at node 81) to the rectified DC voltage rail. Coupling resistor bank 451 to node 81 can help reduce power losses in the receiver tuning components. Connecting bank 451 to node 81 effectively simulates an adjustable load at node 402 (i.e., when Figure 7 When viewed in the direction of arrow 490, group 451 connected at node 81 can still provide load impedance modulation from the perspective of the resonant network of the receiver).

[0087] The pure resistor group 451 is coupled to the node 402. Fig.11 The examples of are also merely illustrative. In general, any type of adjustable load bank including components of real and / or imaginary impedances may be coupled to node 402 (see, e.g., Fig.12 ). Fig.12 A general purpose adjustable load bank 452 is shown that may be provided as part of the power receiving circuit 46. Fig.12As shown, the load group 451 may include both capacitors C1-Cn and resistors R1-Rm. The integers "n" and "m" may have the same or different values. The control circuit 20 may activate only the capacitors (e.g., by switching to use one or more of the capacitors C1-Cn), may activate only the resistors (e.g., by switching to use one or more of the resistors R1-Rm), or may activate both the capacitors and the resistors (e.g., by switching to use at least some of the capacitors C1-Cn and at least some of the resistors R1-Rm in parallel). It is appropriate to activate both the capacitors and resistors in the group 452 at the same time, as long as the impedance real modulation provided by the activated resistor does not offset the impedance imaginary modulation provided by the activated capacitor. Determining which capacitors and / or resistors in the group 452 are to be activated may depend on the rectified voltage output from the rectifier circuit 80 (e.g., a full-bridge rectifier circuit or a half-bridge rectifier circuit), may depend on the size of the output load 82, and / or may depend on one or more of the above-mentioned system parameters.

[0088] If desired, group 452 may also include other types of passive electronic components for modulating the impedance at node 402 (e.g., any combination and number of capacitive, resistive, and / or inductive elements connected in parallel and / or series configurations). In other suitable embodiments, group 452 may include a constant current load or a ballast load. Similar to group 451, adjustable load group 452 may also be provided after rectifier circuit 80 (e.g., after Figure 7 402 at node 81) to the rectified DC voltage rail. Coupling resistor bank 452 to node 81 can help reduce the power loss of the receiver resonant network. Connecting bank 452 to node 81 effectively simulates an adjustable load at node 402 (i.e., when Figure 7 When viewed in the direction of arrow 490, group 452 connected at node 81 can still provide the desired impedance modulation from the perspective of the resonant network of the receiver).

[0089] The above describes techniques that may enable robust data transmission in the context of wireless power transfer.The present disclosure contemplates that it may be desirable for a power transmitter and a power receiver device to communicate information, such as charging status, charging speed, etc., to control power transfer between the devices.

[0090] However, other kinds of data may be transferred, such as data that is more personal in nature. Entities responsible for the collection, analysis, disclosure, transfer, storage, or other use of such personal information data will comply with established privacy policies and / or privacy practices. Specifically, such entities should implement and adhere to privacy policies and practices that are recognized as meeting or exceeding industry or government requirements for maintaining the privacy and security of personal information data. Such policies should be easily accessible to users and should be updated as the collection and / or use of data changes. Personal information from users should be collected for legitimate and reasonable purposes of the entity and not shared or sold outside of these legitimate uses. In addition, such collection / sharing should be carried out after receiving informed consent from the user. In addition, such entities should consider taking any necessary steps to safeguard and secure access to such personal information data and ensure that others who have access to personal information data comply with their privacy policies and processes. In addition, such entities may subject themselves to third-party assessments to demonstrate their compliance with widely accepted privacy policies and practices. In addition, policies and practices should be adjusted to the specific types of personal information data collected and / or accessed, and to applicable laws and standards including specific considerations of jurisdiction. For example, in the United States, the collection or access of certain health data may be governed by federal and / or state laws, such as the Health Insurance Portability and Accountability Act (HIPAA), while health data in other countries may be subject to other regulations and policies and should be handled accordingly. Therefore, different privacy practices should be maintained in each country for different types of personal data.

[0091] To the extent that the present technology is used to transmit personal information data, hardware and / or software elements can be provided to users to selectively block the use or access of personal information data. For example, the present technology can be configured to allow users to "opt in" or "opt out" of the collection of personal information data at any time during or after registration for a service. In addition to providing "opt-in" and "opt-out" options, the present disclosure contemplates providing notifications related to access or use of personal information. For example, users can be notified that their personal information data will be accessed when downloading an application, and then reminded again just before the personal information data is accessed by the application.

[0092] The purpose of the present disclosure is to describe a robust system for data transmission in a wireless power system. In a specific implementation of the present technology, if personal information data is transmitted, the personal information data should be managed and processed in a manner that minimizes the risk of unintentional or unauthorized access or use. Once the data is no longer needed, the risk can be minimized by limiting data collection and deleting the data. In addition, and when applicable, data de-identification can be used to protect the privacy of users. De-identification can be facilitated by removing specific identifiers (e.g., date of birth, etc.), controlling the amount or specificity of stored data (e.g., collecting location data at the city level rather than at the address level), controlling how the data is stored (e.g., aggregating data between users), and / or other methods when appropriate.

[0093] According to an embodiment, a wireless power receiving device is provided, which is configured to receive a wireless power signal from a first wireless power transmission device or a second wireless power transmission device, the wireless power receiving device includes a coil, a wireless power receiving circuit and a control circuit, the wireless power receiving circuit is coupled to the coil and is configured to receive the wireless power signal from the coil, and the control circuit is operable to configure the wireless power receiving device in a first data communication mode when a first magnetic coupling level exists between the coil and the wireless power transmission coil of the first wireless power transmission device, and to configure the wireless power receiving device in a second data communication mode different from the first data communication mode when a second magnetic coupling level exists between the coil and the wireless power transmission coil of the second wireless power transmission device.

[0094] According to another embodiment, a wireless power receiving device includes a first switched capacitor coupled to a first end of a coil, the first switched capacitor being selectively activated during a first data communication mode but not a second data communication mode.

[0095] According to another embodiment, the wireless power receiving device includes a second switched capacitor coupled to the first end of the coil, the second switched capacitor being selectively activated during the second data communication mode but not the first data communication mode.

[0096] According to another embodiment, no switched capacitor is coupled to the second end of the coil.

[0097] According to another embodiment, the first switched capacitor has a first capacitance value and the second switched capacitor has a second capacitance value different from the first capacitance value.

[0098] According to another embodiment, the first magnetic coupling level is greater than the second magnetic coupling level, and the first capacitance value is less than the second capacitance value.

[0099] According to another embodiment, a wireless power receiving device includes a first switch that selectively activates a first switching capacitor and a second switch that selectively activates a second switching capacitor, the first switch being configured to receive a first data communication control signal from a control circuit during a first data communication mode, and the second switch being configured to receive a second data communication control signal from the control circuit during a second data communication mode.

[0100] According to another embodiment, the control circuit is configured to simultaneously modulate the first data communication control signal and the second data communication control signal during a third data communication mode that is different from the first data communication mode and the second data communication mode.

[0101] According to another embodiment, a wireless power receiving device includes a rectifier circuit coupled to a wireless power receiving circuit, the rectifier circuit being operable in at least two different modes.

[0102] According to another embodiment, the rectifier circuit is operable in a full-bridge rectifier mode during the first data communication mode and is operable in a half-bridge rectifier mode during the second data communication mode.

[0103] According to an embodiment, a method for operating a wireless power receiving device having a wireless power receiving coil is provided, the method including receiving a wireless power signal from a first wireless power transmission device at the wireless power receiving coil during a first charging mode, and a first coupling level exists between the wireless power receiving coil and the wireless power transmission coil of the first wireless power transmission device; during a second charging mode, receiving a wireless power signal from a second wireless power transmission device at the wireless power receiving coil, and a second coupling level exists between the wireless power receiving coil and the wireless power transmission coil of the second wireless power transmission device, and the second coupling level is different from the first coupling level, thereby configuring the wireless power receiving device in a first data communication mode during the first charging mode, and configuring the wireless power receiving device in a second data communication mode during the second charging mode.

[0104] According to another embodiment, the method includes control circuitry within the wireless power receiving device determining whether to configure the wireless power receiving device in a first data communication mode or a second data communication mode during a handshake operation.

[0105] According to another embodiment, the method includes, during a handshake operation, initially configuring the wireless power receiving device in a first data communication mode, and in response to performing a successful handshake, causing the wireless power receiving device to continue operating in the first data communication mode; and in response to performing an unsuccessful handshake, causing the wireless power receiving device to be in a second data communication mode.

[0106] According to another embodiment, the method includes selectively activating a first capacitor coupled to a first end of a wireless power receiving coil during a first data communication mode, and selectively activating a second capacitor coupled to the first end of the wireless power receiving coil during a second data communication mode, the first capacitor and the second capacitor having different capacitance values.

[0107] According to another embodiment, the method includes a rectifier circuit in a wireless power receiving device receiving a wireless power signal from a wireless power receiving coil, configuring the rectifier circuit as a full-bridge rectifier during a first data communication mode, and configuring the rectifier circuit as a half-bridge rectifier during a second data communication mode.

[0108] According to an embodiment, a wireless power receiving device is provided, which includes: a coil having a first terminal and a second terminal; a rectifier circuit coupled to the first terminal and the second terminal of the coil; a first passive component coupled to the first terminal of the coil, the first passive component being selectively activated during a first data transmission mode, and the first passive component being configured to provide a first impedance change at the coil; and a second passive component coupled to the first terminal of the coil, the second passive component being selectively activated during a second data transmission mode, and the second passive component being configured to provide a second impedance change at the coil that is different from the first impedance change.

[0109] According to another embodiment, the first passive component and the second passive component include electronic components selected from capacitors and resistors.

[0110] According to another embodiment, the rectifier circuit is configured as a full-bridge rectifier in the first data transmission mode and as a half-bridge rectifier in the second data transmission mode.

[0111] According to another embodiment, the rectifier circuit includes first and second diodes coupled to the first terminal of the coil, a third diode coupled to the second terminal of the coil, and a fourth diode, the fourth diode being short-circuited during the second data transmission mode.

[0112] According to another embodiment, a wireless power receiving device includes a first switch coupled in series with a first passive component, a second switch coupled in series with a second passive component, and a control circuit configured to generate a first control signal for modulating the first switch during a first data transmission mode, and to generate a second control signal for modulating the second switch during a second data transmission mode.

[0113] According to one embodiment, a wireless power receiving device is provided, which is configured to receive a wireless power signal from a wireless power transmitting device, the wireless power receiving device including a coil, a wireless power receiving circuit, an adjustable load group, and a control circuit, the wireless power receiving circuit being coupled to the coil and being configured to receive the wireless power signal from the coil, the adjustable load group being coupled to the coil, the control circuit being operable to configure the wireless power receiving device in a first data communication mode by activating at least a first portion of the adjustable load group, and to configure the wireless power receiving device in a second data communication mode different from the first data communication mode by activating at least a second portion of the adjustable load group.

[0114] According to another embodiment, the control circuit is configured to dynamically adjust the adjustable load bank to ensure that sufficient signal strength is maintained between the wireless power receiving device and the wireless power transmitting device.

[0115] According to another embodiment, the power receiving device includes a rectifier circuit connected to the coil, and the control circuit is further configured to adjust the adjustable load bank based at least in part on a rectified voltage output from the rectifier circuit.

[0116] According to another embodiment, the rectifier circuit is operable in a full-bridge rectifier mode and a half-bridge rectifier mode.

[0117] According to another embodiment, a rectifier circuit is coupled between the coil and the adjustable load bank.

[0118] According to another embodiment, the power receiving device includes an output load coupled to the coil, and the control circuit is further configured to adjust the adjustable load bank based at least in part on a magnitude of the output load.

[0119] According to another embodiment, the wireless power transmission device is of a given transmitter type and operates using a given communication protocol, information about the given transmitter type or the given communication protocol is transmitted from the wireless power transmission device to the control circuit during a handshake operation, and the control circuit is further configured to adjust the adjustable load group based at least in part on the information transmitted during the handshake operation.

[0120] According to another embodiment, the adjustable load bank includes an array of individually selectable components selected from capacitors, resistors, constant current loads, and ballast loads.

[0121] The foregoing is exemplary and various modifications may be made to the embodiments described. The foregoing embodiments may be implemented independently or in any combination.

Claims

1. A power receiving device, comprising: a wireless power transmission coil configured to receive wireless power; a wireless power receiving circuit, the wireless power receiving circuit being coupled to the wireless power transmission coil; as well as A control circuit operable to: configuring the wireless power receiving circuit in a first power transfer mode when a first condition exists between the wireless power transfer coil and a first power transfer device; as well as When a second condition exists between the wireless power transmission coil and a second power transmission device different from the first power transmission device, the wireless power reception circuit is configured in a second power transmission mode different from the first power transmission mode.

2. The power receiving device according to claim 1, wherein: the first condition comprising a first magnetic coupling level between the wireless power transmission coil and a first wireless power transmission coil in the first power transmission device; and The second condition includes a second magnetic coupling level between the wireless power transmission coil and a second wireless power transmission coil in the second power transmission device that is different from the first magnetic coupling level.

3. A power receiving device according to claim 1, wherein the wireless power receiving circuit includes one or more capacitors, at least one of which is selectively activated during the first power transmission mode and selectively deactivated during the second power transmission mode.

4. The power receiving device according to claim 3, wherein the wireless power receiving circuit is further configured to: providing a first amount of impedance at the wireless power transfer coil by selectively activating the at least one of the capacitors during the first power transfer mode; and By selectively deactivating the at least one of the capacitors during the second power transfer mode, a second impedance magnitude different from the first impedance magnitude is provided at the wireless power transfer coil.

5. The power receiving device of claim 3, wherein the wireless power receiving circuit further comprises one or more switches respectively coupled to the one or more capacitors, and wherein the control circuit is further configured to: turning on at least one of the switches to selectively activate the at least one of the capacitors; and The at least one of the switches is turned off to selectively deactivate the at least one of the capacitors.

6. A power receiving device according to claim 1, wherein the wireless power receiving circuit includes a rectifier coupled to the wireless power transmission coil, and wherein the rectifier is configured to operate in a first rectifier mode during the first power transmission mode and in a second rectifier mode different from the first rectifier mode during the second power transmission mode. 7 . The power receiving device of claim 6 , wherein the first rectifier mode comprises a full-bridge rectifier mode, and wherein the second rectifier mode comprises a half-bridge rectifier mode. 8 . The power receiving device of claim 1 , wherein the first power transmitting device comprises an electronic device of a first type, and wherein the second power transmitting device comprises an electronic device of a second type different from the first type.

9. A method of operating a power receiving device, comprising: receiving wireless power from a first power transfer device using a wireless power transfer coil during a first power transfer mode, wherein during the first power transfer mode, a first condition exists between the wireless power transfer coil and a first wireless power transfer coil of the first power transfer device; as well as During a second power transmission mode, wireless power is received from a second power transmission device, wherein during the second power transmission mode, a second condition different from the first condition exists between the wireless power transmission coil and a second wireless power transmission coil of the second power transmission device.

10. The method according to claim 9, wherein: the first condition comprises a first magnetic coupling level between the wireless power transmission coil and the first wireless power transmission coil of the first power transmission device; and The second condition includes a second magnetic coupling level between the wireless power transmission coil and the second wireless power transmission coil of the second power transmission device that is different from the first magnetic coupling level.

11. The method according to claim 9, further comprising: selectively activating at least one capacitor coupled to the wireless power transfer coil during the first power transfer mode; as well as During the second power delivery mode, the at least one capacitor is selectively deactivated.

12. The method according to claim 9, further comprising: A determination is made during a handshake operation whether to operate the power receiving device in the first power transfer mode or in the second power transfer mode.

13. The method according to claim 12, further comprising: during the handshake operation, initially configuring the power receiving device in the first power transfer mode; as well as In response to performing a successful handshake, causing the power receiving device to continue operating in the first power transfer mode.

14. The method according to claim 9, further comprising: receiving a signal from the wireless power transfer coil with a rectifier; configuring the rectifier as a full-bridge rectifier during the first power transfer mode; as well as The rectifier is configured as a half-bridge rectifier during the second power delivery mode.

15. A control circuit coupled to a wireless power transfer coil of an electronic device, the control circuit being operable to: In response to detecting a first condition existing at the wireless power transfer coil, configuring the electronic device in a first power transfer mode; and In response to detecting the presence of a second condition different from the first condition at the wireless power transfer coil, the electronic device is configured in a second power transfer mode.

16. The control circuit according to claim 15, wherein: the first condition comprises a first magnetic coupling level between the wireless power transmission coil and a first wireless power transmission coil of a first power transmission device; and The second condition includes a second magnetic coupling level different from the first magnetic coupling level between the wireless power transmission coil and a second wireless power transmission coil of a second power transmission device different from the first power transmission device.

17. The control circuit according to claim 15, wherein the control circuit is further configured to: selectively activating one or more capacitors coupled to the wireless power transfer coil during the first power transfer mode; and The one or more capacitors are selectively deactivated during the second power delivery mode.

18. The control circuit according to claim 15, wherein the control circuit is further configured to: providing a first amount of impedance at the wireless power transfer coil during the first power transfer mode; and A second impedance magnitude different from the first impedance magnitude is provided at the wireless power transfer coil during the second power transfer mode.

19. The control circuit according to claim 15, wherein the control circuit is further configured to: operating a rectifier coupled to the wireless power transfer coil in a first rectifier mode during the first power transfer mode; and During the second power delivery mode, the rectifier is operated in a second rectifier mode different from the first rectifier mode.

20. The control circuit of claim 19, wherein the first rectifier mode comprises a full-bridge rectifier mode, and wherein the second rectifier mode comprises a half-bridge rectifier mode.

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