Systems and methods for detecting wireless charger coupling

Abstract

The present disclosure relates to systems and methods for detecting wireless charger coupling. Circuitry in an electronic device can use multiple magnetic sensors to detect alternating current signals emitted by a wireless charger and / or to detect magnetic fields produced by one or more magnets in the wireless charger. The circuitry can determine the position of the wireless charger relative to a wireless power transmission coil in the electronic device and provide feedback to guide a user in attaching the wireless charger to the correct location on the electronic device, including visual indications such as on a device display.

Description

[0001] Cross-referencing of related patent applications

[0002] This patent application claims the benefit of U.S. Patent Application 63 / 247,939, filed September 24, 2021, entitled “Systems and Methods for Detecting Wireless Charge Coupling,” pursuant to 35 U.S. SC §119(e), the entire contents of which are incorporated herein by reference. Technical Field

[0003] This disclosure relates in general to wireless charging of electronic devices. Background Technology

[0004] Portable electronic devices such as cell phones, tablets, laptops, and other portable devices use batteries. To improve user convenience, wireless power systems have been provided that allow batteries in portable electronic devices to be charged wirelessly. Coils in wireless power transmitting and receiving devices are used to transmit and receive wireless power signals. Electromagnetic coupling between the transmitting and receiving coils can affect wireless charging efficiency and the power generated in the receiving device. The physical alignment of the transmitting and receiving coils in the X, Y, and Z dimensions affects electromagnetic coupling.

[0005] The foregoing background information is intended to assist the reader only and is not intended to limit the innovations described herein. Therefore, the foregoing should not be used to indicate that any particular element of a prior system is unsuitable for use with the innovations described herein, nor is it intended to indicate that any element is essential for implementing the innovations described herein. Specific implementations and applications of the innovations described herein are defined by the appended claims. Summary of the Invention

[0006] Coils in wireless power transmitting and receiving devices are used to transmit and receive wireless power signals. Electromagnetic coupling between the transmitting and receiving coils can affect wireless charging efficiency and the power generated in the receiving device. When a user attaches a wireless charger to an electronic device, the charger may be attracted by other magnets inside the device (e.g., speakers, haptic modules), resulting in low coupling between the charger's transmitting coil and the electronic device's receiving coil. This can lead to lower charging efficiency or other suboptimal user experiences. This document discloses apparatus, methods, and systems for detecting the position of a wireless charger relative to a wireless power transmission coil in an electronic device. This allows the electronic device to provide feedback to guide the user to attach the charger to the correct position on the device.

[0007] An exemplary embodiment includes an electronic device configured to receive wireless power from a wireless power transmitting device. The electronic device includes a wireless power transmission coil, a plurality of magnetic sensors, a display, and control circuitry. The control circuitry is configured to use the plurality of magnetic sensors to detect alternating current signals transmitted by the wireless power transmitting device and to determine the position of the wireless power transmitting device relative to the wireless power transmission coil. Furthermore, the control circuitry is configured to use the display to present a visual indication of the position of the wireless power transmitting device relative to the wireless power transmission coil.

[0008] Another exemplary embodiment includes an electronic device configured to receive wireless power from a wireless power transmitting device. The wireless power transmitting device includes one or more magnets. The electronic device includes a wireless power transmission coil, a plurality of magnetic sensors, a display, and control circuitry. The control circuitry of the electronic device is configured to use the plurality of magnetic sensors to detect magnetic fields generated by the one or more magnets in the wireless power transmitting device and to determine the position of the wireless power transmitting device relative to the wireless power transmission coil. Furthermore, the control circuitry is configured to use the display to present a visual indication of the position of the wireless power transmitting device relative to the wireless power transmission coil.

[0009] This summary is provided to introduce a series of concepts in a simplified form, which are further described in the detailed description below. This summary is not intended to identify key or essential features of the claimed subject matter, nor is it intended to limit the scope of the claimed subject matter. Furthermore, the claimed subject matter is not limited to addressing any or all of the shortcomings pointed out in any part of this disclosure. Attached Figure Description

[0010] The above-described invention and the following detailed description can be better understood when read in conjunction with the accompanying drawings. In the drawings, numerous specific details are set forth for illustrative purposes to provide an understanding of variations in the implementation of the disclosed technology. However, this disclosure may take many different forms and should not be considered as limited to the specific examples disclosed in the drawings. In practice, similar numerals always refer to similar elements. In the drawings:

[0011] Figure 1 An exemplary wireless power transmission system including a wireless power transmitting device and a wireless power receiving device is shown according to an exemplary embodiment of the present disclosure;

[0012] Figure 2 It is based on the exemplary embodiments of this disclosure. Figure 1 A perspective view of an exemplary wireless power transmitting device shown;

[0013] Figure 3It is based on the exemplary embodiments of this disclosure. Figure 2 A top view of the exemplary wireless power transmitting device shown;

[0014] Figure 4 This is an exemplary graph of sensor measurements according to an exemplary embodiment of the present disclosure, the sensor measurements being used to triangulate the position of a wireless power transmitting device relative to a wireless power transmission coil in an electronic device;

[0015] Figure 5A , Figure 5B and Figure 5C This is an exemplary representation of a user interface on a display of an electronic device according to an exemplary embodiment of the present disclosure, which provides feedback to the user to attach a wireless power transmitting device to the correct location on the electronic device; and

[0016] Figure 6 This is a rear perspective view of another exemplary wireless power receiving device according to an exemplary embodiment of this disclosure. Detailed Implementation

[0017] Figure 1 An exemplary wireless power transmission system 10 is shown, which includes a wireless power transmitting device 30 (i.e., a wireless charger) that transmits power to a wireless power receiving device 20 (i.e., a wireless power receiver). Examples of wireless power receiving devices 20 include electronic devices such as cellular phones, tablets, laptops, or other electronic equipment. The wireless power transmitting device 30 may be a wireless charging dock or wireless charging pad having a wireless power transmission coil 35 and a charging surface 32 for receiving a portable electronic device to be charged. The exemplary wireless power receiving device 20 has a housing 26, which includes a front surface 28 that may be substantially defined by a display screen (not shown) and a rear surface 27 that may be placed on or above the charging surface 32 of the wireless charger 30. The exemplary wireless power receiving device 20 includes one or more wireless power transmission coils 25 on or within the housing 26. The exemplary wireless power receiving device 20 includes a plurality of magnetic sensors 21, 22, 23, 24. The wireless power receiving device uses power from the wireless power transmitting device to power internal components and / or charge an internal battery.

[0018] Coils in power transmitting and receiving devices are used to transmit and receive wireless power signals. The physical alignment of coil 35 in device 30 and coil 25 in device 20 in the X, Y, and Z dimensions affects electromagnetic coupling (also referred to herein as coupling between transmitting device 30 and receiving / electronic device 20). For example, when a user attaches a wireless charger to an electronic device, the charger may be attracted by other magnets inside the electronic device (e.g., speakers, haptic modules), resulting in suboptimal positioning of the charger on the device. This document discloses apparatus, methods, and systems for using magnetic sensors to detect and determine the position of a wireless charger relative to the wireless power transmission coils in an electronic device. This allows the electronic device to provide feedback to guide the user to attach the charger to the optimal position on the electronic device. In some embodiments, sensors for alternating current (AC) fields are used. In some embodiments, sensors for direct current (DC) fields are used.

[0019] Both the wireless power receiving device 20 and the wireless power transmitting device 30 include control circuitry. This control circuitry may include processing circuitry associated with a microprocessor, power management unit, baseband processor, digital signal processor, microcontroller, and / or application-specific integrated circuit (ASIC) having processing circuitry. The processing circuitry implements desired control and communication features in both the electronic device 20 and the power transmitting device 30. For example, the processing circuitry may be used to process sensor data and other data, perform measurements and present information as discussed herein, select coils, adjust the phase and amplitude of coil drive signals, determine power transmission levels, process user input, process negotiations between device 20 and device 30, transmit and receive data, initiate and stop charging operations, and otherwise control the operation of system 10.

[0020] The control circuitry in devices 20 and 30 may be configured to perform operations using hardware (e.g., dedicated hardware or circuitry), firmware, and / or software. Software code for performing operations may be stored on a non-transitory computer-readable storage medium (e.g., a tangible computer-readable storage medium). Software code may sometimes be referred to as software, data, program instructions, commands, or code. Non-transitory computer-readable storage media may include non-volatile memory such as non-volatile random access memory (NVRAM), one or more hard disk drives (e.g., disk drives or solid-state drives), one or more removable flash drives, or other removable media. Software stored on non-transitory computer-readable storage media may execute on the processing circuitry of devices 20 and 30. Processing circuitry may include an application-specific integrated circuit (ASIC) with processing circuitry, one or more microprocessors, a central processing unit (CPU), or other processing circuitry.

[0021] Electronic device 20 includes a housing such as housing 26. Housing 26 has a surface 27 (also referred to herein as rear surface 27) that is positioned on or above the charging surface 32 of device 30 for wireless charging of device 20. For example, during wireless charging, both rear surface 27 and charging surface 32 of device 30 may be substantially parallel to the XY plane. Housing 26 has a front surface 28 substantially defined by a display screen (such as an OLED or LCD display) opposite to rear surface 27.

[0022] Electronic device 20 includes one or more wireless power transmission coils 25 on or within housing 26. Housing 26 may include metallic material, dielectric material, or a combination of these materials and / or other materials. When the coils 25 are mounted within housing 26, housing 26 may include a dielectric portion near the coils to allow external magnetic fields to interact with the coils 25.

[0023] The electronic device 20 also includes multiple magnetic sensors 21, 22, 23, and 24. Figure 1 The exemplary embodiment shown includes four magnetic sensors; however, the present invention may have more or fewer magnetic sensors. These magnetic sensors may be coils or other magnetic sensors such as tunnel magnetoresistive (TMR) sensors, giant magnetoresistive (GMR) sensors, or Hall effect sensors, or any combination thereof. In embodiments of this disclosure, the plurality of magnetic sensors may include a wireless power transmission coil 25.

[0024] As explained in detail below, the control circuitry in electronic device 20 can use the plurality of magnetic sensors to detect the alternating current signal emitted by wireless power transmitter 30 and / or the magnetic field generated by one or more magnets in the wireless power transmitter. Furthermore, the control circuitry in electronic device 20 can determine the position of wireless power transmitter 30 relative to wireless power transmission coil 25 and provide feedback to guide the user to attach device 30 to the correct position on device 20. For example, the control circuitry in electronic device 20 can use electronic device display 29 to present a visual indication of the position of device 30 relative to coil 25.

[0025] Figure 2 It is a perspective view, and Figure 3This is a top view of a wireless power transmitting device 30 in an exemplary configuration. The power transmitting device 30 may be a standalone power adapter (e.g., a wireless charging dock or wireless charging pad including power adapter circuitry), a wireless charging dock or wireless charging pad coupled to a power adapter or other equipment via a cable, or other wireless power transmission equipment. The power transmitting device 30 may be coupled to a wall socket (e.g., an AC power source), may have a battery for power supply, and / or may have another power source. The power transmitting device 30 may have an AC-DC power converter, such as an AC-DC power converter, for converting AC power from the wall socket or other power source into DC power. The wireless power transmitting device 30 is an exemplary configuration of a wireless charging dock, described herein as an example.

[0026] Figure 2 and Figure 3 An exemplary configuration of a wireless power transmitting device 30 as a wireless charging dock is shown. The wireless charging dock includes a housing 36, a charging surface 32, and a flat surface 34 opposite to the charging surface 32 and resting on a lower surface such as a desktop or other surface. The device 30 may have a wireless power transmission coil 35 at the charging surface 32 for transmitting wireless power to the coil 25 in a power receiving device 20. A user can place the device 20 on the charging surface 32 to charge the device 20. During wireless charging, the device 20 ( Figure 1 The rear surface 27 and charging surface 32 are located substantially parallel to Figure 3 In the plane of the XY plane. As shown, the exemplary housing 36 is in the form of a cylindrical base, and the charging surface 32 and the flat surface 34 have circular geometry. Without departing from the scope and spirit of the invention described herein, the housing 36, the charging surface 32, and the flat surface 34 may be configured to have various geometries.

[0027] Embodiments of the wireless power transmitting device 30 also include one or more magnets (not shown), such as permanent magnets. These magnets can generate a specific magnetic field pattern. In some examples, the magnets are arranged circumferentially around the wireless power transmission coil 35.

[0028] Device 30 can use a corresponding inverter to drive wireless power transfer coil 35 to generate a magnetic field. When device 20 is placed on charging surface 32, the magnetic field passes through coil 25 and induces a current in coil 25 for wireless charging of device 20. When coil 25 is centered around coil 35, the electromagnetic coupling between coil 35 and coil 25 is optimized.

[0029] The control circuitry in device 30 may include a power transmission circuitry to transmit wireless power to the power receiving circuitry of device 20. The power transmission circuitry of device 30 may have a switching circuitry (e.g., an inverter circuit formed of transistors) that is switched on or off based on a control signal provided by the control circuitry to generate an AC current signal through one or more transmitting coils 35. During wireless power transmission operation, the power transmission circuitry of device 30 may supply an AC drive signal to one or more coils 35 at a given power transmission frequency. This power transmission frequency may be, for example, about 125 kHz, at least 80 kHz, at least 100 kHz, less than 500 kHz, less than 300 kHz, less than 150 kHz, a predetermined frequency between 80 kHz and 150 kHz, or other suitable wireless power frequencies. In some configurations, the power transmission frequency may be negotiated in communication between device 20 and device 30. In other configurations, the power transmission frequency may be fixed.

[0030] When an AC current passes through one or more coils 35, a time-varying electromagnetic (e.g., magnetic) field (signal) is generated. This time-varying electromagnetic field is received by one or more corresponding receiver coils (such as coil 25) in the power receiving device 20. When this time-varying electromagnetic field is received by coil 25, a corresponding alternating current is induced in coil 25. A rectifier circuit in device 20 (which includes rectifier components, such as synchronous rectifier metal-oxide-semiconductor transistors arranged in a bridging network) converts the AC signal received from coil 25 into a DC voltage signal for powering device 20. The DC voltage generated by the rectifier circuit can be used to power (charge) energy storage devices such as batteries, and can also be used to power other components in device 20.

[0031] As described above, the physical alignment of coil 35 in device 30 and coil 25 in device 20 in the X, Y, and Z dimensions affects the electromagnetic coupling between transmitting device 30 and electronic device 20. A first embodiment that helps a user attach the wireless power transmitting device 30 to the correct position on the electronic device 20 can be characterized as alternating current (AC) field detection. In an exemplary AC field detection embodiment, coil 35 in the wireless power transmitting device 30 generates and transmits an alternating current (AC) magnetic field signal (e.g., "ping"). The transmitted AC signal can be a low-power signal relative to the AC signal generated and transmitted during power transmission operation. The wireless power transmitting device 30 can transmit the AC signal at repeated intervals. For example, device 30 can transmit an AC signal once every 0.1 seconds. Alternatively, device 30 can transmit AC signals at intervals greater than or less than 0.1 seconds. Furthermore, the AC signal can have a pattern that allows control circuitry in electronic device 20 to recognize that the AC signal pattern is associated with a specific type of wireless power transmitting device 30.

[0032] refer to Figure 1 Continuing with the AC field detection implementation scheme, the alternating current signal emitted by device 30 can induce an alternating current voltage in multiple magnetic sensors 21, 22, 23, and 24 within electronic device 20. These magnetic sensors can be coils or other magnetic sensors such as tunnel magnetoresistive (TMR) sensors, giant magnetoresistive (GMR) sensors, or Hall effect sensors. These multiple magnetic sensors may include a wireless power transmission coil 25.

[0033] The control circuitry in device 20 can be configured to measure the level of the alternating current voltage induced in each of the plurality of magnetic sensors 21, 22, 23, 24. Based on the level of the induced voltage, the control circuitry in device 20 can be configured to determine the position of device 30 relative to the wireless power transmission coil 25 in electronic device 20.

[0034] In an exemplary embodiment, the control circuitry in device 20 may be configured to calculate the distance from the wireless power transmitting device 30 to each of the plurality of magnetic sensors 21, 22, 23, 24 using the level of the alternating current voltage sensed in each of these magnetic sensors. Knowing the distance from device 30 to each of the plurality of magnetic sensors, the control circuitry may perform triangulation on the position of device 30 relative to the wireless power transmission coil 25 in electronic device 20, as described below. Figure 4 The detailed explanation follows.

[0035] In an alternative embodiment, the control circuitry in device 20 may be configured to compare the measured level of the alternating current voltage induced in each of the plurality of magnetic sensors 21, 22, 23, 24 with a value in a lookup table to determine the position of device 30 relative to the wireless power transmission coil 25 of electronic device 20. For example, the lookup table may be created during a calibration phase in which the wireless power transmission device 30 is placed at multiple known locations relative to the wireless power transmission coil 25 in electronic device 20. At each of these known locations, device 30 may transmit an alternating current signal that induces an alternating current voltage in the plurality of magnetic sensors 21, 22, 23, 24. The level of the alternating current voltage induced in each sensor may be measured in a manner associated with each of the multiple known locations and stored in the lookup table. The lookup table may be stored in the memory of device 20.

[0036] Optionally, during the calibration phase, the induced voltage values ​​for the plurality of magnetic sensors can be repeatedly measured and stored in a lookup table at each of a plurality of known locations, wherein the wireless power transmitting device 30 is in a different orientation relative to the wireless power transmitting coil 25. For example, the plurality of known locations may include those relative to device 20 ( Figure 1 The rear surface 27 of the device 30 is oriented in three dimensions along the X, Y, and Z axes. This can be implemented on the charging surface 32 of the device 30. Figure 3 The device 30 contacts the rear surface 27 of the device 20 (i.e., zero offset on the Z-axis) and the power line 39 of the device 30 is in the first direction (e.g., as shown in the image). Figure 1 In the case of extending in the 6 o'clock direction (as shown), measurements are performed and stored for various X and Y coordinate positions. The device 30 can rotate about the Z-axis, causing the power line 39 of the device 30 to extend in other directions, and measurements can be repeated and stored for various X and Y coordinate positions. Similarly, measurements can be performed and stored for various offsets in the Z-axis, where the rear surface 27 and the charging surface 32 are in substantially parallel planes. Furthermore, measurements can be performed and stored for various offsets in the Z-axis, where the rear surface 27 and the charging surface 32 are not in parallel planes. Therefore, the lookup table allows the control circuitry in the device 20 to determine the position and orientation of the device 30 relative to the wireless power transmission coil 25 based on the induced voltage values ​​measured by the plurality of magnetic sensors 21, 22, 23, 24.

[0037] Following the calibration phase (which may occur during the design and / or manufacturing process of devices 20 and 30), device 20 can acquire measurements from magnetic sensors 21, 22, 23, and 24 during operation and compare these acquired values ​​with entries in a lookup table. Device 20 can then determine the position and, optionally, orientation of device 30 by identifying the lookup entry that most closely matches the measured sensor values. For example, various techniques such as distance and matrix norm functions can be used to quantify the difference between a single entry in the lookup table (e.g., representing position and orientation) and a set of measured magnetic sensor output values, in addition to multiple entries in the lookup table. Various techniques such as gradient descent, simplex method, and differential evolution algorithms can be used to determine the lookup table entry that best matches the set of measured magnetic sensor output values.

[0038] Although the exemplary embodiments described above and Figure 1 The original design referenced four magnetic sensors, but AC field detection can be achieved with other numbers of sensors, with a larger number of sensors generally resulting in higher detection fidelity, and vice versa. In implementations involving additional mechanical constraints between the transmitter and receiver, a minimum number of sensors can be used. For example, a single sensor can sense whether a bullet-shaped wireless power receiver is in an acceptable wireless charging position within a cylindrical sleeve wireless power transmitter.

[0039] After the control circuitry in device 20 determines the position of device 30 relative to the wireless power transmission coil 25, the control circuitry can trigger the user interface to provide feedback, guiding the user to attach device 30 to the correct position on electronic device 20. See below for reference. Figures 5A to 5C As explained, the user interface can use the display 29 in device 20 to present a visual indication of the position of the wireless power transmitting device 30 relative to the wireless power transmission coil 25.

[0040] In AC field detection, one or more of the multiple magnetic sensors in device 20 can be configured to actively search for AC signals emitted by wireless power transmitter 30. This configuration of the magnetic sensors actively searching for AC signals from the charger can consume the battery in device 20. Therefore, a lower power option may be needed for detecting AC signals. For example, wireless power transmitter 30 may include one or more magnets. The multiple magnetic sensors in electronic device 20 may include DC magnetometers, and the control circuitry in device 20 can be configured to use the DC magnetometers to detect changes in the magnetic field. Once the control circuitry in device 20 detects a change in the magnetic field, it can activate the AC sensors to actively search for AC signals emitted by wireless power transmitter 30.

[0041] In another example, device 20 may have dedicated circuitry to detect alternating current (AC) signals emitted by wireless power transmitting device 30. This dedicated circuitry may include a bandpass filter, a rectifier, and a capacitor. The bandpass filter may be configured to allow only the frequency of the AC signal to pass through, which can be used to charge the capacitor via the rectifier. Control circuitry in device 20 may be configured to measure the potential across the capacitor. Once the control circuitry measures the desired charge in the capacitor, it can trigger the processes discussed above to measure the level of AC induced in each magnetic sensor, determine the distance of device 30 to each of the plurality of sensors, thereby determining the position of device 30 relative to coil 25, and display a visual indication of the position of device 30 to guide the user to attach device 30 to the correct location on electronic device 20.

[0042] An alternative implementation that helps the user attach the wireless power transmitting device 30 to the correct location on the electronic device 20 can be characterized as detection based on a direct current (DC) field. Referring to the implementation for first DC field detection... Figure 1 , Figure 2 and Figure 3The wireless power transmitting device 30 may include one or more magnets. The one or more magnets in device 30 may include permanent magnets. Furthermore, the one or more magnets may be circumferentially arranged around the wireless power transmission coil 35 in device 30. The one or more magnets in device 30 may generate a magnetic field. Alternatively, the one or more magnets in device 30 may generate a specific magnetic field pattern.

[0043] The control circuitry in device 20 may be configured to use a plurality of magnetic sensors 21, 22, 23, 24 in device 20 to detect magnetic fields generated by one or more magnets in device 30. Alternatively, the control circuitry in device 20 may be configured to use a plurality of magnetic sensors 21, 22, 23, 24 in device 20 to detect specific magnetic field patterns generated by one or more magnets in device 30. By detecting specific magnetic field patterns, the control circuitry in device 20 may be able to determine that the specific magnetic field pattern is associated with a specific wireless power transmitting device 30 (i.e., a specific type of wireless charger), which may allow the control circuitry to reject any unwanted magnetic interference from other devices. These magnetic sensors may be coils or other magnetic sensors such as tunnel magnetoresistive (TMR) sensors, giant magnetoresistive (GMR) sensors, or Hall effect sensors, or any combination thereof. In embodiments of this disclosure, the plurality of magnetic sensors may include a wireless power transmission coil 25.

[0044] Once a magnetic field or a specific magnetic field pattern has been detected, the control circuitry in device 20 can be configured to determine the position of the wireless power transmitting device 30 relative to the wireless power transmission coil 25 within device 20. In an exemplary embodiment, the control circuitry in device 20 may use multiple magnetic sensors 21, 22, 23, 24 to measure the magnetic field and determine the distance from device 30 to each of the multiple magnetic sensors based on the magnetic field measured in each magnetic sensor. The control circuitry in device 20 can then determine the position of the wireless power transmitting device 30 relative to the wireless power transmission coil 25 by triangulating the distances from device 30 to the multiple magnetic sensors 21, 22, 23, 24, as described below. Figure 4 The detailed explanation follows.

[0045] In an alternative embodiment, the control circuitry in device 20 may be configured to use a plurality of magnetic sensors 21, 22, 23, 24 to measure the magnetic field, and to compare the magnetic field measurement results from each of the plurality of magnetic sensors with values ​​in a lookup table to determine the position of device 30 relative to the wireless power transmission coil 25 of electronic device 20. For example, the lookup table may be created during a calibration phase in which the wireless power transmission device 30 is placed at multiple known locations relative to the wireless power transmission coil 25 in electronic device 20. At each of these known locations, the magnetic field generated by one or more magnets in device 30 may be measured using the plurality of magnetic sensors 21, 22, 23, 24. The magnetic field measurement results from each of the plurality of magnetic sensors may be stored in the lookup table and associated with the corresponding known position of electronic device 30 relative to electronic device 20. The lookup table may be stored in the memory of device 20.

[0046] Optionally, during the calibration phase, magnetic field measurements for the plurality of magnetic sensors can be repeatedly measured and stored in a lookup table at each of a plurality of known locations, wherein the wireless power transmitting device 30 is oriented differently relative to the wireless power transmitting coil 25. For example, the plurality of known locations may include those relative to device 20 ( Figure 1 The rear surface 27 of the device 30 is oriented in three dimensions along the X, Y, and Z axes. This can be implemented on the charging surface 32 of the device 30. Figure 3 The device 30 contacts the rear surface 27 of the device 20 (i.e., zero offset on the Z-axis) and the power line 39 of the device 30 is in the first direction (e.g., as shown in the image). Figure 1 In the case of extending in the 6 o'clock direction (as shown), measurements are performed and stored for various X and Y coordinate positions. Device 30 can rotate about the Z-axis, allowing the power line 39 of device 30 to extend in other directions, and measurements can be repeated and stored for various X and Y coordinate positions. Similarly, measurements can be performed and stored for various offsets in the Z-axis, where the rear surface 27 and charging surface 32 are in substantially parallel planes. Furthermore, measurements can be performed and stored for various offsets in the Z-axis, where the rear surface 27 and charging surface 32 are not in parallel planes. Therefore, the lookup table allows the control circuitry in device 20 to determine the position and orientation of device 30 relative to the wireless power transmission coil 25 based on the magnetic field measurements from multiple magnetic sensors 21, 22, 23, and 24.

[0047] Following the calibration phase (which may occur during the design and / or manufacturing process of devices 20 and 30), device 20 can acquire measurements from magnetic sensors 21, 22, 23, and 24 during operation and compare these acquired values ​​with entries in a lookup table. Device 20 can then determine the position and, optionally, orientation of device 30 by identifying the lookup entry that most closely matches the measured sensor values. For example, various techniques such as distance and matrix norm functions can be used to quantify the difference between a single entry in the lookup table (e.g., representing position and orientation) and a set of measured magnetic sensor output values, in addition to multiple entries in the lookup table. Various techniques such as gradient descent, simplex method, and differential evolution algorithms can be used to determine the lookup table entry that best matches the set of measured magnetic sensor output values.

[0048] Although the exemplary embodiments described above and Figure 1 The original design referenced four magnetic sensors, but DC field detection can be achieved with other numbers of sensors, with a larger number of sensors generally resulting in higher detection fidelity, and vice versa. In implementations involving additional mechanical constraints between the transmitter and receiver, a minimum number of sensors can be used. For example, a single sensor can sense whether a slingback wireless power receiver is in an acceptable wireless charging position within a cylindrical sleeve wireless power transmitter.

[0049] After the control circuitry in device 20 determines the position of device 30 relative to the wireless power transmission coil 25, the control circuitry can trigger the user interface to provide feedback, guiding the user to attach device 30 to the correct position on electronic device 20. See below for reference. Figures 5A to 5C As discussed, the user interface can use the display 29 in device 20 to present a visual indication of the position of the wireless power transmitting device 30 relative to the wireless power transmission coil 25.

[0050] Figure 4 This is an exemplary graph 100 for sensor detection and measurement used to perform triangulation of the wireless power transmitting device 30 relative to the wireless power transmission coil 25 in the electronic device 20. As shown, graph 100 includes an X-axis and a Y-axis. The origin, represented by point 125, is located at... Figure 1 The wireless power transmitting coil 25 in the electronic device 20 shown is located at the center. Graph 100 includes curves corresponding to... Figure 1The magnetic sensor in the diagram comprises four magnetic sensors: sensor 1 (121), sensor 2 (122), sensor 3 (123), and sensor 4 (124). Each sensor performs measurements in three dimensions (i.e., spheres). Furthermore, the four magnetic sensors are configured in a single sensor plane. Since each sphere representing the measurement performed by the respective sensor is symmetrical to the sensor plane, the intersecting circle between two spheres is perpendicular to the sensor plane. Therefore, the projected shape of the intersecting circle is a simple line.

[0051] Information from three sensors is required to triangulate the position of the wireless power transmitter 30. In this example, sensors 1 (121), 2 (122), and 3 (123) are used to determine the position of device 30. Dashed line 126 represents the X-coordinate of device 30 and is the intersection of sphere 121A (measured by sensor 1 (121)) and sphere 123A (measured by sensor 3 (123)). Dashed line 127 represents the Y-coordinate of device 30 and is the intersection of sphere 121A (measured by sensor 1 (121)) and sphere 122A (measured by sensor 2 (122)). Therefore, point 128 (the intersection of lines 126 and 127) represents the position of the wireless power transmitter 30 relative to the wireless power transmission coil 25 in device 20.

[0052] Figure 4 This is applied to both AC field detection and DC field detection implementation schemes. In an exemplary AC field detection implementation scheme, the control circuitry in device 20 can measure the level of an AC voltage induced in each of a plurality of sensors via an AC signal emitted by device 30. The control circuitry can be further configured to use the measured level of the AC voltage induced in at least a subset of the plurality of sensors to triangulate the position of device 30 relative to the wireless power transmission coil 25 in device 20. In an exemplary DC field detection implementation scheme, the control circuitry in device 20 can use a plurality of magnetic sensors to measure a magnetic field generated by one or more magnets in the wireless power transmitting device 30. The control circuitry can be further configured to use the magnetic field measured by at least a subset of the plurality of magnetic sensors to triangulate the position of device 30 relative to the wireless power transmission coil 25 in device 20.

[0053] The X, Y, and Z coordinates of device 30 can be calculated using the equations explained below. In an exemplary operation of the DC field detection implementation, each sensor is measuring the magnetic field generated by one or more permanent magnets in device 30. In these equations, m1 is the distance from the center of sensor 1 (121) to the magnetic field 121A it measures; m2 is the distance from the center of sensor 2 (122) to the magnetic field 122A it measures; and m3 is the distance from the center of sensor 3 (123) to the magnetic field 123A it measures.

[0054] Furthermore, "a" is the distance from the center of sensor 1 (121) to the dashed line 127; "b" is the distance from the center of sensor 2 (122) to the dashed line 127; "c" is the distance from the center of sensor 1 (121) to the dashed line 126; and "e" is the distance from the center of sensor 3 (123) to the dashed line 126. The positions of the sensors relative to each other can be determined through the design configuration. Therefore, the distance between sensor 1 (121) and sensor 2 (122) can be configured to be the same as the distance between sensor 1 (121) and sensor 3 (123). Therefore, a + b = d; and c + e = d, where "d" is the distance between sensor 1 and sensor 2, which is the same as the distance between sensor 1 and sensor 3.

[0055] The Y coordinate can be calculated using information from sensors 1 (121) and 2 (122) and the following equation:

[0056] m1 2 –a 2 =m2 2 -b 2

[0057] a+b=d

[0058]

[0059]

[0060] When calculating the Y-coordinate, if m² is greater than d, a plus sign (+) should be used. Otherwise, a minus sign (-) should be used.

[0061] The X coordinate of device 30 can be calculated using information from sensor 1 (121) and sensor 3 (123) and the following equation:

[0062] m1 2 -c 2 =m3 2 –e 2

[0063] c + e = d

[0064]

[0065]

[0066] When calculating the X-coordinate, if m3 is greater than d, a plus sign (+) should be used. Otherwise, a minus sign (-) should be used.

[0067] Once the X and Y coordinates are known, the Z coordinate can be calculated using the center position and distance from any sensor. The following equation uses information from sensor 1 to calculate the Z coordinate:

[0068]

[0069] Figure 5A , Figure 5B and Figure 5C This is a representation of an exemplary user interface visualized on the display 29 of the electronic device 20, which provides feedback to guide the user to attach the wireless power transmitter 30 to the correct location on the electronic device 20. Figures 5A to 5C The front surface 28 and display 29 of electronic device 20 are shown. After the control circuitry in device 20 determines the position of device 30 relative to the wireless power transmission coil 25 in device 20, as discussed above, the control circuitry can use display 29 to present a visual indication of the position of device 30 relative to coil 25. In the example shown, ring 52 is a visual representation of the position of wireless power transmission coil 25, and rings 53A and 53B are visual representations of the position of device 30. Figure 5A and Figure 5B As most clearly seen, when the user moves the device 30 relative to the coil 25, the control circuitry in the device 20 uses the new position of the device 30 to update the display 29. In the accompanying drawings, the user is moving the device 30 from its position in the upper left corner of the device 20 (shown as...). Figure 5A 53A) is moved diagonally downwards to a position closer to coil 25 (shown as...). Figure 5A (53A in the original text). Ring 52 has a static position because the wireless power transmission coil 25 does not move. When device 30 is positioned within a specific tolerance range of coil 25, the control circuitry in device 20 can update the display to indicate that device 30 is correctly positioned relative to device 20. For example, as... Figure 5C As shown, the control circuitry can display a single shape 55. In another example, the control circuitry can change the color of the visual indicator 55 and / or the brightness of the displayed visual indicator 55. In another example, the control circuitry can cause the device 20 to produce sound. In yet another example, the control circuitry in the device 20 can display symbols and / or text on the display 29.

[0070] As referenced above Figure 2 and Figure 3 As explained, the wireless power transmitting device 30 includes a housing 36 and a charging surface 32, which are respectively cylindrical and circular in geometry. The housing 36 and charging surface 32 of the device 30 are not limited to... Figure 2 and Figure 3 The exemplary geometry described herein can be configured to have various geometries without departing from the scope and spirit of the invention as described herein. Thus, when the control circuitry of device 20 uses a display to present a visual indication of the location of the wireless power transmitting device 30, the control circuitry may present a visual representation of the geometry of the housing 36 and / or charging surface 32. In another embodiment, the size of the visual representation of the geometry on display 29 may be the same as the size of the housing 36 and / or charging surface 32.

[0071] Figure 6 This is a rear perspective view of an alternative exemplary electronic device 200 according to aspects of this disclosure. Device 200 has a number of elements similar to those of electronic device 20. Where appropriate, similar numerals have been used for similar features of devices 200 and 20. Figure 6 As shown, the electronic device 200 includes a housing such as housing 226. Housing 226 has a surface 227 (also referred to herein as rear surface 227) that is positioned on or above the charging surface 32 of device 30 for wireless charging of device 200. For example, during wireless charging, both rear surface 227 and charging surface 32 of device 30 may be substantially parallel. Figure 6 The XY plane. The housing 226 has a front surface 228 defined substantially by a display screen (e.g., an OLED display) 229, which is opposite to the rear surface 227.

[0072] Electronic device 200 includes one or more wireless power transmission coils 225 on or within housing 226. Housing 226 may include metallic material, dielectric material, or a combination of these materials and / or other materials. When the coils 225 are mounted within housing 226, housing 226 may include a dielectric portion near the coils to allow external magnetic fields to interact with the coils 225.

[0073] like Figure 6 As shown, the electronic device 200 also includes a plurality of magnetic sensors arranged in a sensor array. In an exemplary embodiment, the plurality of magnetic sensors in the sensor array may be arranged in a row and column structure. Figure 6 The exemplary implementation shown includes an array with five rows (210, 220, 230, 240, and 250) and five columns (A, B, C, D, and E). As shown, the multiple magnetic sensors in this array can also be positioned such that the number of magnetic sensors in each row and / or column alternates. Figure 6The example includes 13 magnetic sensors positioned in alternating rows and columns, with rows 210, 230, and 250 each containing three magnetic sensors; rows 220 and 240 each containing two magnetic sensors; columns A, C, and E each containing three magnetic sensors; and columns B and D each containing two magnetic sensors. The number and location of the magnetic sensors in the sensor array of device 200 are not limited to... Figure 6 The embodiments shown in the diagram. For example, device 200 may have more or fewer magnetic sensors and may be arranged in arrays with different configurations. The magnetic sensors in the sensor array may be coils or other magnetic sensors such as tunnel magnetoresistive (TMR) sensors, giant magnetoresistive (GMR) sensors, or Hall effect sensors, or any combination thereof. In embodiments of this disclosure, the plurality of magnetic sensors includes a wireless power transmission coil 225.

[0074] Electronic device 200 can be used in alternative detection implementation schemes based on alternating current (AC) fields and / or direct current (DC) fields to help the user attach wireless power transmitting device 30 to the correct location on electronic device 200. As mentioned above, a higher number of sensors may generally result in higher detection fidelity.

[0075] In the AC field detection implementation scheme, the coil 35 in the wireless power transmitting device 30 periodically generates and transmits alternating current (AC) magnetic field signals (e.g., "ping"). The transmitted AC signal can be a low-power signal relative to the AC signal generated and transmitted during wireless power transmission operation. The wireless power transmitting device 30 can transmit the AC signal at repeated intervals. For example, the device 30 can transmit an AC signal once every 0.1 seconds. Alternatively, the device 30 can transmit AC signals at intervals greater than or less than 0.1 seconds. Furthermore, the AC signal can have a pattern (predetermined and known to the electronic device 200) such that the control circuitry in the electronic device 200 can recognize that the AC signal pattern is associated with a specific type of wireless power transmitting device 30.

[0076] The alternating current signal emitted by device 30 can induce an alternating current voltage in multiple sensors of a sensor array in electronic device 200. The control circuitry in device 200 can be configured to measure the level of the alternating current voltage induced in each magnetic sensor of the sensor array. Based on the level of the induced voltage, the control circuitry in device 200 can be configured to determine the position of device 30 relative to the wireless power transmission coil 225 in electronic device 200.

[0077] In an exemplary embodiment, the control circuitry in device 200 may be configured to calculate the distance from the wireless power transmitting device 30 to each sensor using the level of the alternating current voltage induced in each magnetic sensor of the sensor array. Knowing the distance from device 30 to each sensor in the sensor array, the control circuitry may perform triangulation on the position of device 30 relative to the wireless power transmission coil 225 in electronic device 200, as referenced above. Figure 4 The detailed explanation follows.

[0078] In another embodiment, the control circuitry in device 200 may be configured to compare the measured level of the alternating current voltage sensed in each magnetic sensor of the sensor array with values ​​in a lookup table to determine the position of device 30 relative to wireless power transfer coil 225. The sensor array-based lookup table can be created during the calibration phase in the same manner as explained above regarding the multiple sensors 21, 22, 23, 24 in reference device 20. As explained above, the lookup table may also include measurements for different orientations of device 30, enabling the control circuitry in device 200 to use measurements from multiple sensors in the sensor array to determine the position and orientation of device 30 relative to wireless power transfer coil 225. During operation, the control circuitry of device 200 may use digital optimization methods such as gradient descent, simplex method, and differential evolution to determine the position of device 30 relative to coil 225 that minimizes the difference between the measured alternating current voltage value and the values ​​in the lookup table for the positions of the multiple magnetic sensors in the sensor array.

[0079] In an alternative DC field-based detection implementation, the wireless power transmitting device 30 may include one or more magnets. The one or more magnets in device 30 may include permanent magnets. Furthermore, the one or more magnets may be circumferentially arranged around the wireless power transmission coil 35 in device 30. The one or more magnets in device 30 may generate a magnetic field. Alternatively, the one or more magnets in device 30 may generate a specific magnetic field pattern.

[0080] Functionally similar to device 20 as explained above, the control circuitry in device 200 (using multiple sensors in a sensor array) can detect magnetic fields generated by one or more magnets in the wireless power transmitter 30 and determine the position of the wireless power transmitter 30 relative to the wireless power transmission coil 225 in device 200. In another embodiment, the control circuitry in device 200 may be configured to use multiple magnetic sensors in the sensor array to detect a specific magnetic field pattern generated by one or more magnets in device 30 and determine the position of device 30 relative to coil 225. By detecting a specific magnetic field pattern, the control circuitry in device 200 may be able to determine that the specific magnetic field pattern is associated with a specific wireless power transmitter 30 (i.e., a specific type of wireless charger), which allows the control circuitry to reject any unwanted magnetic interference from other devices.

[0081] Once a magnetic field or a specific magnetic field pattern has been detected, the control circuitry in device 200 can be configured to determine the position of the wireless power transmitting device 30 relative to the wireless power transmission coil 225 in device 200. In an exemplary embodiment, the control circuitry in device 200 may use multiple sensors of a sensor array to measure the magnetic field and determine the distance from device 30 to each magnetic sensor in the sensor array based on the magnetic field measured in each magnetic sensor. The control circuitry in device 200 may then determine the position of the wireless power transmitting device 30 relative to the wireless power transmission coil 225 by triangulating the distances from device 30 to the multiple magnetic sensors in the sensor array, as referenced above. Figure 4 The detailed explanation follows.

[0082] In an alternative embodiment, the control circuitry in device 200 may be configured to measure a magnetic field using multiple magnetic sensors in a sensor array and compare the magnetic field measurements from each magnetic sensor in the sensor array with values ​​in a lookup table to determine the position of device 30 relative to wireless power transmission coil 225. The sensor array-based lookup table can be created during the calibration phase in the same manner as explained above with reference to the multiple sensors 21, 22, 23, 24 in device 20. As explained above, the lookup table may also include measurements for different orientations of device 30, enabling the control circuitry in device 200 to use measurements from multiple sensors in the sensor array to determine the position and orientation of device 30 relative to wireless power transmission coil 225. During operation, the control circuitry of device 200 may use digital optimization methods such as gradient descent, simplex method, and differential evolution to determine the position of device 30 relative to coil 225 that minimizes the difference between the magnetic field measured at each of the multiple magnetic sensor positions in the sensor array and the values ​​in the lookup table.

[0083] The foregoing description is provided for illustrative purposes and should not be construed as limiting the invention. While the invention has been described with reference to illustrative examples or methods, it should be understood that the terms used herein are descriptive and illustrative, not limiting. Furthermore, although the invention has been described herein with reference to specific structures, methods, and examples, the invention is not intended to be limited to the specific details disclosed herein, as the invention extends to all structures, methods, and uses within the scope of the appended claims. Those skilled in the art who benefit from the teachings of this specification will be able to make numerous modifications to the invention as described herein, and changes can be made without departing from the scope and spirit of the invention as defined by the appended claims.

Claims

1. An electronic device configured to receive wireless power from a wireless power transmitting device, the electronic device comprising: Wireless power transfer coil; Multiple magnetic sensors, including DC sensors and AC sensors; monitor; and Control circuit, the control circuit being configured to: The magnetic field was detected from the wireless power transmitting device using the DC sensor. Activate the AC sensor to search for AC signals emitted by the wireless power transmitter; One or more of the plurality of magnetic sensors are used to detect the alternating current signal emitted by the wireless power transmitting device; Determine the position of the wireless power transmitting device relative to the wireless power transmission coil; as well as The display is used to present a visual indication of the position of the wireless power transmitting device relative to the wireless power transmission coil.

2. The electronic device of claim 1, wherein the plurality of magnetic sensors include the wireless power transmission coil.

3. The electronic device of claim 1, wherein the control circuit is further configured to use at least one of the plurality of magnetic sensors to detect changes in the magnetic field.

4. The electronic device of claim 1, further comprising a capacitor, wherein the capacitor is capable of being charged by the alternating current signal emitted by the wireless power transmitting device, and wherein the control circuitry is further configured to measure the potential across the capacitor.

5. The electronic device of claim 1, wherein the control circuit is further configured to measure the level of the alternating current voltage induced in the plurality of magnetic sensors by means of the alternating current signal transmitted by the wireless power transmitting device.

6. The electronic device of claim 5, wherein the control circuit is further configured to determine the distance from the wireless power transmitting device to each of the plurality of magnetic sensors based on the measured level of the alternating current voltage sensed in each magnetic sensor.

7. The electronic device of claim 6, wherein the control circuit determines the position of the wireless power transmitting device relative to the wireless power transmission coil by triangulating the distances from the wireless power transmitting device to at least three of the plurality of magnetic sensors.

8. The electronic device of claim 5, wherein the control circuit determines the position of the wireless power transmitting device relative to the wireless power transmission coil by comparing the measured level of the alternating current voltage induced in each of the plurality of magnetic sensors with a value in a lookup table.

9. The electronic device of claim 1, wherein the wireless power transmitting device transmits the AC signal at repeated intervals.

10. The electronic device of claim 1, wherein the alternating current signal has a pattern, and wherein using the plurality of magnetic sensors to detect the alternating current signal emitted by the wireless power transmitting device includes detecting the pattern.

11. The electronic device of claim 1, wherein the wireless power transmitting device includes a housing surface having a geometry, and wherein using the display to present a visual indication of the position of the wireless power transmitting device relative to the wireless power transmission coil includes presenting a visual representation of the geometry.

12. The electronic device of claim 11, wherein the size of the housing surface is the same as the size of the visual representation of the geometry.

13. An electronic device configured to receive wireless power from a wireless power transmitting device, the electronic device comprising: Wireless power transfer coil; Multiple magnetic sensors; monitor; and Control circuit, the control circuit being configured to: Using the plurality of magnetic sensors to detect a magnetic field generated by one or more magnets in the wireless power transmitting device, wherein the one or more magnets in the wireless power transmitting device have a specific magnetic field pattern, and wherein using the plurality of magnetic sensors to detect the magnetic field generated by the one or more magnets in the wireless power transmitting device includes determining whether the detected magnetic field includes the specific magnetic field pattern; Determine the position of the wireless power transmitting device relative to the wireless power transmission coil; as well as The display is used to present a visual indication of the position of the wireless power transmitting device relative to the wireless power transmission coil.

14. The electronic device of claim 13, wherein the plurality of magnetic sensors include the wireless power transmission coil.

15. The electronic device of claim 13, wherein the control circuit is further configured to: The magnetic field is measured using the plurality of magnetic sensors; and The distance from the wireless power transmitter to each of the plurality of magnetic sensors is determined based on the magnetic field measured in each magnetic sensor.

16. The electronic device of claim 15, wherein the control circuit determines the position of the wireless power transmitting device relative to the wireless power transmission coil by triangulating the distances from the wireless power transmitting device to at least three of the plurality of magnetic sensors.

17. The electronic device of claim 13, wherein the control circuit determines the position of the wireless power transmitting device relative to the wireless power transmitting coil by: The magnetic field is measured using the plurality of magnetic sensors; and The magnetic field measurement results from each of the plurality of magnetic sensors are compared with the values ​​in the lookup table.

18. The electronic device of claim 13, wherein the one or more magnets in the wireless power transmitting device are permanent magnets.

19. The electronic device of claim 13, wherein the wireless power transmitting device further comprises a wireless power transmission coil, and the one or more magnets in the wireless power transmitting device are circumferentially arranged around the wireless power transmission coil.

20. The electronic device of claim 13, wherein the wireless power transmitting device includes a housing surface having a geometry, and wherein using the display to present a visual indication of the position of the wireless power transmitting device relative to the wireless power transmission coil includes presenting a visual representation of the geometry.

21. The electronic device of claim 20, wherein the size of the housing surface is the same as the size of the visual representation of the geometry.

22. The electronic device of claim 13, wherein the plurality of magnetic sensors are arranged in an array.

23. The electronic device of claim 22, wherein the plurality of magnetic sensors in the array are arranged in a row and column structure.

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