Magnetic configurations for wireless power transfer and communication in electronic devices

Abstract

The device may include a wireless power transmission coil that is couplable to a complementary wireless power transmission coil of another device. The device may further include wireless power transmitting and / or receiving circuitry, a processing and communication system, and a wireless communication coil coupled to the processing and communication system. The communication coil may include a winding that is magnetically couplable to a corresponding communication coil of the complementary device to enable communication between the processing and communication system and the complementary device. The wireless communication coil may be separated from the power transmission coil along a longitudinal axis of the device.

Description

[Technical field]

[0001] (CROSS REFERENCE TO RELATED APPLICATIONS) This application claims priority to U.S. Provisional Patent Application No. 63 / 167,795, filed March 30, 2021, and entitled “Magnetics Configurations for Wireless Power Transfer and Communications in Electronic Device Accessories,” the disclosure of which is incorporated by reference in its entirety and for all purposes. background

[0002] Wireless Power Transfer ("WPT"), sometimes also known as Inductive Power Transfer ("IPT"), has become more popular in recent years in several applications. One application in which WPT / IPT is increasingly being used is in consumer electronics peripherals such as mobile phones (i.e., smartphones) and their accessories (e.g., wireless earbuds, smart watches, etc.), as well as tablets and other types of portable computers and their accessories (e.g., styluses, etc.). Summary of the Invention

[0003] The device may include a power receiving coil configured to be magnetically coupled to a power transmitting coil of a wireless power transmitter, a wireless power receiving circuit component configured to receive energy from the power receiving coil, a processing and communication system powered by the wireless power receiving circuit component, and a wireless communication coil coupled to the processing and communication system. The communication coil may include a winding configured to be magnetically coupled to a corresponding communication coil of the wireless power transmitter to enable communication between the processing and communication system and the wireless power transmitter. The wireless communication coil may be separated from the power receiving coil along a longitudinal axis of the device.

[0004] The device may be a wireless earphone, and a longitudinal axis of the device may be a longitudinal axis of a stem portion of the wireless earphone. The power receiving coil may include a hemispherical magnetic core and a winding disposed around an exterior of the hemispherical core. The power receiving coil may be configured to be disposed within a hemispherical power transmitting coil of a wireless power transmitter. The power receiving coil may be located at a distal end of the stem portion of the wireless earphone. The device may further include a shield disposed between the power receiving coil and the wireless communication coil. At least one of a height of the communication coil and a vertical separation between the communication coil and the power receiving coil may be selected to provide a desired degree of magnetic isolation between the communication coil and the power receiving coil.

[0005] The communications coil may include a magnetic core. The magnetic core may have a cross-sectional area smaller than a cross-sectional area of ​​the windings of the communications coil, and the magnetic core may be disposed behind the windings in an opening in the windings. The magnetic core may have a cross-sectional area larger than a cross-sectional area of ​​the windings of the communications coil, and the windings may be disposed in a channel in the magnetic core. A vertical dimension of the communications coil along a longitudinal axis of the device may be greater than a horizontal dimension of the communications coil transverse to the longitudinal axis of the device. A vertical dimension of the communications coil along a longitudinal axis of the device may be less than a horizontal dimension of the communications coil transverse to the longitudinal axis of the device.

[0006] The device may include a power transmitting coil configured to be magnetically coupled to a power receiving coil of a wireless power receiver, wireless power transmission circuitry configured to transmit energy through the power transmitting coil, a processing and communication system, and a wireless communication coil coupled to the processing and communication system. The communication coil may include a winding configured to be magnetically coupled to a corresponding communication coil of the wireless power receiver to enable communication between the processing and communication system and the wireless power receiver. The wireless communication coil may be separated from the power transmitting coil along a longitudinal axis of the device.

[0007] The device can be an earbud charging case, and a longitudinal axis of the device can correspond to a longitudinal axis of a stem portion of the wireless earbud. The earbud charging case can include one or more alignment features configured to position the earbud relative to the case for proper alignment of the coil. The power transmitting coil can include a hemispherical shelled magnetic core and a winding disposed about an interior of the hemispherical shell. The power transmitting coil can be configured to be disposed about a hemispherical power receiving coil of the wireless power receiver. The power transmitting coil can be located within a portion of the case configured to receive a distal end of the stem portion of the wireless earbud, and the device can further include shielding disposed between the power transmitting coil and the wireless communication coil. At least one of a height of the communication coil and a vertical separation between the communication coil and the power transmitting coil can be selected to provide a desired degree of magnetic isolation between the communication coil and the power transmitting coil.

[0008] The communications coil may include a magnetic core. The magnetic core may have a cross-sectional area smaller than a cross-sectional area of ​​the windings of the communications coil, and the magnetic core may be disposed behind the windings in an opening in the windings. The magnetic core may have a cross-sectional area larger than a cross-sectional area of ​​the windings of the communications coil, and the windings may be disposed in a channel in the magnetic core. A vertical dimension of the communications coil along a longitudinal axis of the device may be greater than a horizontal dimension of the communications coil transverse to the longitudinal axis of the device. A vertical dimension of the communications coil along a longitudinal axis of the device may be less than a horizontal dimension of the communications coil transverse to the longitudinal axis of the device. [Brief description of the drawings]

[0009] [Figure 1] 1 shows a wireless power transfer system. [Diagram 2] FIG. 1 is a block diagram of an application example of a wirelessly powered peripheral device and a wireless charging case. [Figure 3A] 1 illustrates an example wireless power transfer system configuration that includes a communication coil vertically separated from a power coil. [Figure 3B]1 illustrates an example wireless power transfer system configuration that includes a communication coil vertically separated from a power coil. [Figure 4] 3C shows a side view illustrating a further optional arrangement of the vertically separated power and communication coils shown in FIGS. 3A-3B. FIG. [Figure 5A] 5 illustrates an optional ferrite configuration for the vertically separated / displaced communication coil arrangement described above with respect to FIGS. 3A-3B and 4. FIG. [Figure 5B] 5 illustrates an optional ferrite configuration for the vertically separated / displaced communication coil arrangement described above with respect to FIGS. 3A-3B and 4. FIG. [Figure 6A] 5 illustrates an alternative optional ferrite configuration for the vertically separated / displaced communication coil arrangement described above with respect to FIGS. 3A-3B and 4. FIG. [Figure 6B] 5 illustrates an alternative optional ferrite configuration for the vertically separated / displaced communication coil arrangement described above with respect to FIGS. 3A-3B and 4. FIG. [Figure 7A] 5 illustrates an alternative optional ferrite configuration for the vertically separated / displaced communication coil arrangement described above with respect to FIGS. 3A-3B and 4. FIG. [Figure 7B] 5 illustrates an alternative optional ferrite configuration for the vertically separated / displaced communication coil arrangement described above with respect to FIGS. 3A-3B and 4. FIG. [Figure 7C] 5 illustrates an alternative optional ferrite configuration for the vertically separated / displaced communication coil arrangement described above with respect to FIGS. 3A-3B and 4. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] In the following description, for the convenience of explanation, numerous specific details are set forth to enhance the understanding of the disclosed concepts. As part of this description, some of the drawings in the present disclosure represent structures and devices in block diagram form to avoid obscuring the present invention. In the interest of clarity, not all features of an actual implementation are described herein. Moreover, the language used in this specification has been selected solely for purposes of readability and explanation, and not to limit or restrict the disclosed subject matter. Rather, the appended claims are intended for such purposes.

[0011] Various embodiments of the disclosed concepts are illustrated in the accompanying drawings, by way of example and not by way of limitation, in which like reference numerals refer to like elements. For simplicity and clarity of illustration, where considered appropriate, reference numerals have been repeated in different drawings to indicate corresponding and / or similar elements. In other instances, numerous specific details have been described to provide a thorough understanding of the implementations described herein. In other instances, methods, procedures, and components have not been described in detail so as not to obscure the relevant associated functions being described. References to "an", "one", or "another" embodiment in the present disclosure are not necessarily to the same or different embodiments, but rather to at least one. A given drawing is used to illustrate multiple embodiments of the present disclosure or multiple species of the present disclosure, and not all elements in the drawing may be required in a given embodiment or species. A reference numeral, when provided in a given drawing, refers to the same element throughout several drawings, but may not be repeated in all drawings. The drawings are not to scale unless otherwise indicated and the proportions of certain parts may be exaggerated to better show the details and features of the present disclosure.

[0012] FIG. 1 shows a simplified block diagram of a wireless power transfer system 100. The wireless power transfer system includes a power transmitter (PTx) 110 that wirelessly transmits power to a power receiver (PRx) 120 via inductive coupling 130. The power transmitter 110 can receive input power that is converted to an AC voltage having specific voltage and frequency characteristics by an inverter 114. The inverter 114 can be controlled by a controller / communication module 116 that operates as described further below. In various embodiments, the inverter controller and communication module may be implemented in a common system, such as a system based on a microprocessor, microcontroller, or the like. In other embodiments, the inverter controller may be implemented by a separate controller module and communication module having means of communication therebetween. The inverter 114 may be configured using any suitable circuit topology (e.g., full bridge, half bridge, etc.) and may be implemented using any suitable semiconductor switching device technology (e.g., MOSFETs, IGBTs, etc. fabricated using silicon, silicon carbide, or gallium nitride devices).

[0013] The inverter 114 can deliver the generated AC voltage to the transmitter coil 112. In addition to the wireless coil that allows for magnetic coupling to the receiver, the transmitter coil block 112 shown in FIG. 1 may include tuning circuit components, such as additional inductors and capacitors, that facilitate operation of the transmitter in different conditions, such as different degrees of magnetic coupling to the receiver, different operating frequencies, etc. The wireless coil itself can be configured in a variety of different ways. In some embodiments, the wireless coil can be formed as a winding of wire wound around a suitable bobbin. In other embodiments, the wireless coil can be formed as a trace on a printed circuit board. Other arrangements are possible and can be used in conjunction with the various embodiments described herein. The wireless transmitter coil can also include a core of magnetically permeable material (e.g., ferrite) configured to affect the magnetic flux pattern of the coil in a manner suitable for a particular application. The teachings herein can be applied in conjunction with any of a wide variety of transmitter coil arrangements suitable for a given application.

[0014] The PTx controller / communication module 116 can monitor the power transmitter coil and use information derived therefrom to appropriately control the inverter 114 depending on a given situation. For example, the controller / communication module can be configured to operate the inverter 114 at a given frequency or output voltage depending on a particular application. In some embodiments, the controller / communication module can be configured to receive information from the PRx device and control the inverter 114 accordingly. This information may be received via the power transmission coil (i.e., in-band communication) or may be received via a separate communication channel (not shown, i.e., out-of-band communication). In the case of in-band communication, the controller / communication module 116 can detect and decode signals (such as voltage, frequency, or load changes) applied by the PRx to the magnetic link to receive information, and can command the inverter to modulate the power delivered by manipulating various parameters (such as voltage, frequency, etc.) of the generated voltage to transmit information to the PRx. In some embodiments, the controller / communication module may be configured to employ Frequency Shift Keying (FSK) communication, in which the frequency of the inverter signal is modulated, to communicate data to the PRx. The controller / communication module 116 may be configured to detect Amplitude Shift Keying (ASK) communication or load modulation based communication from the PRx. In either case, the controller / communication module 126 may be configured to vary the current drawn at the PRx to manipulate the waveform seen at the Tx coil to deliver information from the PRx to the PTx. For out-of-band communication, additional modules may be provided that enable communication between the PTx and PRx, such as WiFi, Bluetooth, or other wireless links, or any other suitable communication channel.

[0015] As mentioned above, the controller / communications module 116 may be, for example, a single module provided on a single integrated circuit, or may be comprised of multiple modules / devices provided on different integrated circuits, or a combination of integrated circuits and discrete circuits having both analog and digital components. The teachings herein are not limited to any particular arrangement of controller / communications circuitry.

[0016] The PTx device 110 may optionally include other systems and components, such as a separate communications module 118. In some embodiments, the communications module 118 can communicate with a corresponding module tag in the PTx via a power transmission coil. In other embodiments, the communications module 118 can communicate with a corresponding module using a separate physical channel 138.

[0017] As mentioned above, the wireless power transmission system also includes a wireless power receiver (PRx) 120. The wireless power receiver may include a receiver coil 122 that may be magnetically coupled 130 to the transmitter coil 112. Similar to the transmitter coil 112 described above, the receiver coil block 122 shown in FIG. 1 may include tuning circuit components such as additional inductors and capacitors to facilitate operation of the transmitter in different conditions, such as different degrees of magnetic coupling to the receiver, different operating frequencies, etc. The wireless coil itself may be configured in a variety of different ways. In some embodiments, the wireless coil may be formed as a winding of wire wound around a suitable bobbin. In other embodiments, the wireless coil may be formed as a trace on a printed circuit board. Other arrangements are possible and may be used in conjunction with the various embodiments described herein. The wireless receiver coil may also include a core of magnetically permeable material (e.g., ferrite) configured to affect the magnetic flux pattern of the coil in a manner suitable for a particular application. The teachings herein may be applied in conjunction with any of a wide variety of receiver coil arrangements suitable for a given application.

[0018] The receiver coil 122 outputs an AC voltage induced therein by magnetic induction through the transmitter coil 112. This output AC voltage may be provided to a rectifier 124 that provides DC output power to one or more loads associated with the PRx device. The rectifier 124 may be controlled by a controller / communication module 126 that operates as described further below. In various embodiments, the rectifier controller and communication module may be implemented in a common system, such as a system based on a microprocessor, microcontroller, or the like. In other embodiments, the rectifier controller may be implemented by a separate controller module and communication module having means of communication therebetween. The rectifier 124 may be configured using any suitable circuit topology (e.g., full bridge, half bridge, etc.) and may be implemented using any suitable semiconductor switching device technology (e.g., MOSFETs, IGBTs, etc. fabricated using silicon, silicon carbide, or gallium nitride devices).

[0019] The PRx controller / communication module 126 can monitor the receiver coil and use information derived therefrom to appropriately control the rectifier 124 depending on a given situation. For example, the controller / communication module can be configured to operate the rectifier 124 to provide a given output voltage depending on a particular application. In some embodiments, the controller / communication module can be configured to transmit information to the PTx device to effectively control the power delivered to the receiver. This information may be received and transmitted via the power transmitting coil (i.e., in-band communication) or may be transmitted via a separate communication channel (not shown, i.e., out-of-band communication). In the case of in-band communication, the controller / communication module 126 can, for example, modulate the load current or other electrical parameters of the received power to transmit information to the PTx. In some embodiments, the controller / communication module 126 can be configured to detect and decode signals (such as voltage, frequency, or load variations) applied by the PTx to the magnetic link in order to receive information from the PTx. In some embodiments, the controller / communication module 126 may be configured to receive frequency shift keying (FSK) communications, where the frequency of the inverter signal is modulated to communicate data to the PRx. The controller / communication module 126 may be configured to generate amplitude shift keying (ASK) communications or load modulation based communications from the PRx. In either case, the controller / communication module 126 may be configured to vary the current drawn at the PRx to manipulate the waveform seen at the Tx coil to deliver information from the PRx to the PTx. For out-of-band communications, additional modules may be provided that enable communication between the PTx and PRx, such as WiFi, Bluetooth, or other wireless links, or any other suitable communication channel.

[0020] As mentioned above, the controller / communications module 126 may be, for example, a single module provided on a single integrated circuit, or may be comprised of multiple modules / devices provided on different integrated circuits, or a combination of integrated circuits and discrete circuits having both analog and digital components. The teachings herein are not limited to any particular arrangement of controller / communications circuitry.

[0021] The PRx device 120 may optionally include other systems and components, such as a communications ("comms") module 128. In some embodiments, the communications module 128 may communicate with a corresponding module in the PTx via the power transmission coil. In other embodiments, the communications module 128 may communicate with a corresponding module or tag using a separate physical channel 138.

[0022] Many variations and extensions of the above-described wireless power transfer system 100 are possible, and the following teachings are applicable to any such variations and extensions.

[0023] FIG. 2 is a block diagram of an application example of a wirelessly powered peripheral 202 and a wireless charging case 204. In one embodiment, the wireless peripheral can be a pair of wireless earphones. The wireless earphones may be designed such that a speaker portion can be inserted into a user's ear and a stem portion containing other electronic components can extend therefrom. The loudspeaker can be driven with an audio signal generated by a digital-to-analog converter and amplified by an audio amplifier. The digital-to-analog converter can receive a digital audio signal from a processor and communications module 224. In some embodiments, the processor and communications module 224 can receive a digital audio signal from another device, such as a mobile phone, a tablet computer, a laptop computer, or other source, via Bluetooth, WiFi, or another suitable wireless communications protocol. A corresponding radio is not explicitly shown in the block diagram of FIG. 2, but it will be understood that such a radio module can be incorporated into the processing and communications module or can be a separate module. The various electronic modules that make up the wireless earphones (or any other peripheral device 202) are merely illustrative, and additional components (e.g., microphones) or other functional blocks may be included as appropriate to a given embodiment. Other permutations and combinations are possible, as are different embodiments.

[0024] The electronic system of the wireless peripheral may be powered by an internal rechargeable battery (not shown). The battery may be charged by wireless power transmission using a wireless power receiver (PRx) 226, which may be coupled to a receiving coil 227 and configured to receive wireless power from a corresponding transmitter 246 and transmitting coil 247 in the charging case 204. As an example, the wireless power transmission system may be configured as described above with respect to FIG. 1. The wireless peripheral 202 may be inserted into the charging case 204, which may have one or more receiving portions configured to receive the peripheral 202. These receiving portions may be shaped to receive and align the peripheral 202 such that the wireless power receiver coil 227 in the wireless peripheral 202 is properly aligned with the corresponding wireless power transmitter coil 247 in the charging case 204. This alignment may be achieved by the shape of the receiving portion (corresponding to the shape of the peripheral 202) or may be further assisted by other features such as alignment tabs or other fasteners, magnets, or other suitable alignment devices.

[0025] The charging case 204 may include its own battery (not shown) that may provide an energy source for charging the wireless peripheral device 202. The battery may be charged by an external wired or wireless power source (not shown). The case battery may be coupled to a power management circuit 242, which may in turn provide power to a wireless power transmitter 246, which may be configured to wirelessly deliver power to a corresponding wireless peripheral device power receiver coil 227 and wireless power receiver 226 via a power transmission coil 247. The power management circuit 242 may also be coupled to a case processing system 243, which may be a programmable controller configured to operate the charging case. The processing system 243 may be coupled to a case communication module 244, which may be configured to provide communication between the wireless charging case 204 and the wireless peripheral device 202. Such communication may be provided by a communication coil 248 configured to be magnetically coupled to a corresponding communication coil 228 of the wireless peripheral device 202 when the wireless peripheral device 202 is inserted within the case 204. Although communications coils may be referred to herein as "transmitter" or "receiver" coils, all such coils may be used bidirectionally and thus may transmit or receive power as required by the particular context and mode of operation.

[0026] As briefly described above with respect to FIG. 1, some wireless power transfer systems rely on so-called "in-band" communication, where the power delivery from the PTx to the PRx is modulated to provide communication. However, in some cases, it may be desirable to provide out-of-band communication. For example, out-of-band communication may allow for a wider communication bandwidth. These out-of-band communications have historically relied on radio frequencies for physical channels. Alternatively, as described herein, magnetic induction may be used. However, when magnetic induction is used for communication and power delivery, it may be desirable to ensure that there is sufficient isolation between the power transfer path (e.g., from the PTx 246 to the power receiving coils 227 and PRx 226 via the power transmitting coil 247) and the communication path (between the earbud processor / communication module 224 and the case communication module 244 via the communication coils 228 and 248). Various embodiments for providing such isolation are described below.

[0027] In some embodiments, isolation between the magnetic circuit path used for power transmission and the magnetic circuit path used for communication between the wireless charging case 204 and the wireless peripheral 202 (or other wireless device) may be achieved by providing sufficient physical separation between the power coil and the communication coil. In the case of a wireless peripheral 202 configured as described above, this may include, for example, locating the wireless power receiver coil 227 near the bottom of the wireless peripheral 202 and locating the corresponding wireless power transmitter coil 247 at a corresponding location within the case. Similarly, the peripheral communication coil 228 may be located at a higher location within the wireless peripheral 202 and the corresponding case communication coil 248 may be located at a corresponding location within the case. For example, in the case of a wireless earbud as the peripheral 202, the power receiver coil may be located near the distal end of the stem portion of the wireless peripheral, while the communication receiver coil may be located at a higher location within the stem portion, closer to the top of the earbud that is inserted into the user's ear, or even as part of such top. The illustrated configuration in which the power coil and communication coil are disposed below / above each other is merely exemplary; any spatially separated configuration can be used, regardless of orientation. Each of the aforementioned coils can include a winding portion made up of several turns of wire, printed circuit board traces, flexible printed circuit traces, etc. Each of the aforementioned coils can also include a core made of a material having an appropriate magnetic permeability (e.g., ferrite) to enhance the performance of the magnetic circuit. A series of magnetic circuit configurations that use separation between the power coil and communication coil to achieve the desired isolation are described below.

[0028] 3A-3B show a configuration including a communication coil vertically separated from a power coil. More specifically, FIG. 3A includes a side view 300a and FIG. 3B includes a top view 300b. In an exemplary embodiment, the power receiving coil 227 may be disposed at the bottom of the wireless peripheral device. The power receiving coil may include a winding 227a and a magnetic core (also known as a ferrite) 227b. In the illustrated embodiment, the ferrite 227b has a generally hemispherical shape, and the winding 227a is wound complementarily around the outside of the core. Thus, the power receiving coil may have a generally hemispherical shape that may correspond to the shape of the end of the wireless peripheral device 202.

[0029] When placed in the case, the corresponding power transmitting coil 247 can be positioned such that the power transmitting coil 247 is properly coupled to the power receiving coil 227 when the peripheral device is inserted into the case. The wireless power transmitting coil 247 can include a winding portion 247a and a magnetic core / ferrite 247b. The magnetic core 247b can be a generally hemispherical shell to correspond to the core of the power receiving coil 227. In this case, the power transmitting winding 227a can be wound to fit inside the hemispherical shell to form a generally hemispherical power transmitting winding. Thus, when the earbuds are placed in the case, the power receiving coil 227 of the earbuds can be located substantially within the power transmitting coil 247, allowing for proper magnetic coupling between the two and facilitating power transfer. Additionally, the power transmitting coil core 247b can have slots or air gaps 247c disposed therein to facilitate coil manufacturing and / or to control magnetic flux, if desired. In addition, although hemispherical power windings are described in the illustrated embodiments, it will be understood that generally planar coil configurations or other three-dimensional coil configurations may also be used as desired or appropriate for a given embodiment.

[0030] The wireless peripheral device 202 may also include an earbud communication coil 228 that may be vertically displaced along the longitudinal axis of the stem portion of the wireless earbud so as to be separated from the power coil described above. (This arrangement is also suggested by the block diagram of FIG. 2). Similarly, the charging case 204 may have a case communication coil 248 disposed therein in a complementary position, also displaced from the power coil, thereby providing isolation between the magnetic circuit used for power transfer from the case to the earbuds and the magnetic circuit used for communication between the case and the earbuds. As illustrated in FIGS. 3A-3B, when the peripheral device is disposed within the case, the communication coils 228 and 248 may be appropriately aligned to provide sufficient magnetic coupling for the desired communication operation.

[0031] FIG. 4 shows a side view (300c) of a further optional arrangement of the vertically separated power coil and communication coil shown in FIGS. 3A-3B. The side view 300c shows the arrangement of FIGS. 3A-3B with an optional shielding portion 301 between the power coil and the communication coil. The shielding portion 301 may be made of copper or any other conductor and may function to provide a better degree of insulation between the power coil and the communication coil than would be provided by vertical separation alone. Thus, the inclusion of the shielding portion may allow for better magnetic isolation when using the same spacing, or may allow for the same degree of magnetic isolation with less spacing. In the illustrated embodiment, the first shielding member element 301a is disposed between the wireless power receiving coil 227 and the vertically separated / displaced communication coil 228 in the wireless peripheral device 202. Similarly, the second shielding member 301b is disposed between the wireless power transmitting coil 247 and the vertically separated / displaced communication coil 248 in the charging case 204. Side view 300d, as compared to side view 300c, illustrates an arrangement in which the height of communication coils 228 and 248 may be reduced to provide further separation between the power coils and the communication coils, and thus provide a greater degree of insulation. The particular dimensions and displacements of the coils may be determined as appropriate for any given embodiment. Additionally, while side view 300d illustrates optional shielding members 301a / 301b, it should be understood that the reduced height of the coils may be used with or without this optional shielding, resulting in various permutations of combinations that may be selected depending on the particular performance goals and spatial constraints of a given system.

[0032] The communication coils 228 and 248 may be constructed without a high permeability core member (as shown in FIGS. 3A-3B). However, in some embodiments, it may be preferable to include a magnetic core to improve the performance of the communication coil. FIGS. 5A-5B show in two views an optional ferrite configuration for the vertically separated / displaced communication coil arrangement described above with respect to FIGS. 3A-3B and 4. FIG. 5A includes a side view 300e and FIG. 5B includes a top view 300f. The power winding arrangement of FIGS. 5A-5B is as described above with respect to FIGS. 3A-3B and 4. The case communication coil 248 may include a core 306 that may be constructed of any material having a desired magnetic permeability, such as ferrite. Similarly, the peripheral communication coil 228 may include a core 304 that is similarly constructed of a suitable material. These cores may be shaped to provide the desired magnetic flux paths for a given embodiment. In the illustrated embodiment, the cross-sectional area of ​​the core is smaller than the cross-sectional area of ​​the corresponding coil winding, so that the core may be disposed within the opening of the winding, i.e., such that the coil surrounds the core when viewed through the opening of the winding. Additionally, the core may be disposed "behind" the corresponding winding, such that earbud core 304 is disposed toward the interior of earbud 202a and case core 306 is disposed toward the interior of case 204. In other words, the windings of earbud communication coil 228 and the windings of case communication coil 248 may face each other with their respective cores / ferrites behind them.

[0033] 6A-6B show in two views an alternative optional ferrite configuration for the vertically separated / displaced communication coil arrangement described above with respect to FIGS. 3A-3B and 4. FIG. 6A includes a side view 300g and FIG. 6B includes a top view 300h. The power winding arrangement of FIGS. 6A-6B is as described above with respect to FIGS. 3A-3B and 4. The case communication coil 248 may include a core 310 that may be constructed of any material having a desired magnetic permeability, such as ferrite. Similarly, the peripheral communication coil 228 may include a core 308 that is similarly constructed of a suitable material. These cores may be shaped to provide the desired magnetic flux path for a given embodiment. In the illustrated embodiment, the cross-sectional area of ​​the core is larger than the cross-sectional area of ​​the corresponding coil winding. However, as in the embodiment of FIGS. 5A-5B, the cores are still positioned "behind" the corresponding windings, such that the peripheral core 308 is positioned toward the interior of the peripheral 202 and the case core 310 is positioned toward the interior of the case 204. In other words, the windings of earbud communication coil 228 and case communication coil 248 can face each other with their respective cores / ferrites at the back. Additionally, the communication coil arrangements of FIGS. 6A-6B are configured such that the vertical dimension of the communication coil (as shown) is smaller than the horizontal dimension of the communication coil (as shown). It will be understood that "vertical" and "horizontal" merely refer to the orientation in the figures provided, and need not be vertical, horizontal, or any other particular orientation in an actual embodiment. These terms simply refer to the respective orthogonal dimensions of the coils.

[0034] 7A-7C show in three views an alternative optional ferrite configuration for the vertically separated / displaced communication coil arrangement described above with respect to FIGS. 3A-3B and 4. FIG. 7A includes a side view 300i, FIG. 7B includes a top view 300j, and FIG. 7C shows a coil cross-sectional view 300k. The power winding arrangements of FIGS. 7A-7C are as described above with respect to FIGS. 3A-3B and 4. The case communication coil 248 may include a core 314 that may be constructed of any material having a desired magnetic permeability, such as ferrite. Similarly, the peripheral communication coil 228 may include a core 310 that is similarly constructed of a suitable material. These cores may be shaped to provide the desired magnetic flux path for a given embodiment. In the illustrated embodiment, the cross-sectional area of ​​the core is larger than the cross-sectional area of ​​the corresponding coil winding. Additionally, the windings may be disposed within the core, such as within channels formed within the core. However, as in the embodiment of FIGS. 5A-5B, the cores are still positioned "behind" the corresponding windings, such that the peripheral core 312 is positioned toward the interior of the earbud 202a and the case core 314 is positioned toward the interior of the case 204. In other words, the windings of the peripheral communication coil 228 and the windings of the case communication coil 248 can face each other, with their respective cores / ferrites behind. In addition, the communication coil arrangements of FIGS. 7A-7C are configured such that the vertical dimension of the communication coil (as shown) is smaller than the horizontal dimension of the communication coil (as shown). It will be understood that "vertical" and "horizontal" merely refer to the directions in the figures provided, and need not be vertical, horizontal, or any other particular orientation in an actual embodiment. These terms merely refer to the respective orthogonal dimensions of the coils.

[0035] Various aspects of the vertically separated communications coils as described above with respect to Figures 3A-7C, including vertical separation distance, vertical coil extent, shielding, the presence and configuration of magnetic cores, and coil dimensions, can be tailored or adapted as appropriate for any given application. Thus, there are a wide variety of vertically displaced coil arrangements that may be suitable for any given application, depending on the particular objectives and constraints of such system.

[0036] The above describes an exemplary embodiment of a wireless power transfer system that provides isolation between a magnetic circuit used for power transfer and a magnetic circuit used for communication. Such a system may be used in a variety of applications, but may be particularly advantageous when used with personal electronic devices, such as mobile computing devices (e.g., laptop computers, tablet computers, smartphones, etc.) and their accessories (e.g., wireless earphones, styluses and other input devices, etc.), as well as wireless charging accessories (e.g., charging mats, charging pads, charging stands, etc.). Although a number of specific features and various embodiments have been described, it should be understood that the various features and embodiments may be combined in various permutations in a particular implementation, unless otherwise specified as mutually exclusive. Thus, the various embodiments described above are provided by way of example only and should not be construed as constituting the scope of the present disclosure. Various modifications and variations may be made to the principles and embodiments herein without departing from the scope of the present disclosure and without departing from the scope of the claims.

[0037] The above describes an exemplary embodiment of a wireless power transfer system that can transmit certain information between the PTx and PRx in the system. The present disclosure contemplates that the communication of this information will improve the ability of devices to efficiently and non-damagingly provide wireless power signals to each other to facilitate battery charging. It is contemplated that some implementers of the present technology may consider communication of identifiers such as serial numbers, UIDs, manufacturer IDs, MAC addresses, etc. to aid in identifying the PTx and PRx from each other, particularly their wireless capabilities.

[0038] To the extent that sensitive information is transmitted between wireless transceivers in the above-described embodiments of a wireless charging system, entities implementing the present technology should take care to ensure that the transmission of sensitive information is done in compliance with well-established privacy policies and / or privacy practices. Specifically, such entities would be expected to implement and consistently apply privacy practices that are generally recognized as meeting or exceeding industry or government requirements for maintaining user privacy. Implementers should inform users when personally identifiable information is expected to be transmitted in a wireless power transmission system and allow users to "opt-in" or "opt-out" of participation. For example, such information may be presented to a user when the user places a device on a power transmitter.

[0039] Moreover, it is the intent of this disclosure that personal information data should be managed and handled in a way that minimizes the risk of unintentional or unauthorized access or use. Risks can be minimized by limiting data collection and deleting data that is no longer needed. Alternatively, and when applicable, data de-identification can be used to protect user privacy. For example, device identifiers can be partially masked to convey device characteristics without uniquely identifying the device. De-identification may be facilitated by removing identifiers when appropriate, controlling the amount or specificity of data stored (e.g., collecting location data at a city level rather than an address level), controlling how data is stored (e.g., aggregating data across users), and / or other methods such as differential privacy. Robust encryption may also be utilized to reduce the likelihood that communications between inductively coupled devices will be spoofed.

Claims

1. A wireless earphone, a power receiving coil configured to be magnetically coupled to a power transmitting coil of a wireless power transmitter; wireless power receiving circuitry configured to receive energy from the power receiving coil; a processing and communication system powered by the wireless power receiving circuitry; and a wireless communications coil coupled to the processing and communication system, the wireless communications coil including a winding configured to be magnetically coupled to a corresponding communications coil of the wireless power transmitter to enable communications between the processing and communication system and the wireless power transmitter; the wireless communication coil is separated from the power receiving coil along a longitudinal axis of a stem portion of the wireless earphone; the power receiving coil is disposed at a distal end of the stem portion of the wireless earphone. Wireless earphones.

2. 10. The wireless earphone of claim 1, wherein the power receiving coil includes a hemispherical magnetic core and a winding disposed around an exterior of the hemispherical magnetic core.

3. The wireless earphone of claim 2 , wherein the power receiving coil is configured to be disposed within a hemispherical power transmitting coil of the wireless power transmitter.

4. The wireless earphone of claim 1 , further comprising a shield disposed between the power receiving coil and the wireless communication coil.

5. 10. The wireless earphone of claim 1 , wherein a distance along a longitudinal axis of the wireless earphone between the communications coil and the power receiving coil is selected to provide a desired degree of magnetic isolation between the communications coil and the power receiving coil.

6. The wireless earphone of claim 1 , wherein the communication coil includes a magnetic core.

7. 7. The wireless earphone of claim 6, wherein the magnetic core has a cross-sectional area smaller than a cross-sectional area of ​​the windings of the communication coil, the magnetic core being disposed within an opening in the windings.

8. 7. The wireless earphone of claim 6, wherein the magnetic core has a cross-sectional area larger than a cross-sectional area of ​​the windings of the communication coil, the windings being disposed within channels in the magnetic core.

9. 7. The wireless earphone of claim 6, wherein a vertical dimension of the communication coil along the longitudinal axis of the wireless earphone is greater than a horizontal dimension of the communication coil transverse to the longitudinal axis of the wireless earphone.

10. 7. The wireless earphone of claim 6, wherein a vertical dimension of the communication coil along the longitudinal axis of the wireless earphone is smaller than a horizontal dimension of the communication coil transverse to the longitudinal axis of the wireless earphone.

11. A wireless earphone charging case, a power transmitting coil configured to be magnetically coupled to a power receiving coil of a wireless power receiver; wireless power transmission circuitry configured to transmit energy via the power transmission coil; a processing and communication system; a wireless communications coil coupled to the processing and communication system, the wireless communications coil including a winding configured to be magnetically coupled to a corresponding communications coil of the wireless power receiver to enable communications between the processing and communication system and the wireless power receiver; the wireless communication coil is separated from the power transmission coil along a longitudinal axis that corresponds to a stem portion of a wireless earphone that is received in the wireless earphone charging case; the power transmission coil is disposed in a portion of the wireless earphone charging case configured to receive a distal end of the stem portion of the wireless earphone. Wireless earphone charging case.

12. 12. The wireless earphone charging case of claim 11, wherein the earphone charging case includes one or more alignment features configured to position an earphone relative to the case for proper alignment of the coil of the wireless power receiver and the coil of the wireless communication coil.

13. 12. The wireless earphone charging case of claim 11, wherein the power transmission coil includes a hemispherical shell magnetic core and a winding disposed around the interior of the hemispherical shell.

14. 14. The wireless earphone charging case of claim 13, wherein the power transmitting coil is configured to be disposed around a hemispherical power receiving coil of the wireless power receiver.

15. 12. The wireless earphone charging case of claim 11, further comprising a shield disposed between the power transmission coil and the wireless communication coil.

16. 12. The wireless earphone charging case of claim 11, wherein a distance along the longitudinal axis of the wireless earphone between the communications coil and the power transmission coil is selected to provide a desired degree of magnetic isolation between the communications coil and the power transmission coil.

17. The wireless earphone charging case of claim 11 , wherein the communication coil includes a magnetic core.

18. 18. The wireless earphone charging case of claim 17, wherein the magnetic core has a cross-sectional area smaller than a cross-sectional area of ​​the windings of the communication coil, and the magnetic core is positioned behind the windings within an opening in the windings.

19. 20. The wireless earphone charging case of claim 18, wherein the magnetic core has a cross-sectional area larger than the cross-sectional area of ​​the winding of the communication coil, the winding being disposed within a channel in the magnetic core.

20. 20. The wireless earphone charging case of claim 18, wherein a vertical dimension of the communications coil along the longitudinal axis of the wireless earphone charging case is greater than a horizontal dimension of the communications coil transverse to the longitudinal axis of the wireless earphone charging case.

21. 20. The wireless earphone charging case of claim 18, wherein a vertical dimension of the communications coil along the longitudinal axis of the wireless earphone charging case is smaller than a horizontal dimension of the communications coil transverse to the longitudinal axis of the wireless earphone charging case.

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