Electronic device, method of operating electronic device, and wireless charging system

Abstract

An electronic device, a method of operating an electronic device, and a wireless charging system are disclosed. The electronic device includes an LC circuit including a coil and a first capacitor, and configured to receive a power signal through induction of the coil, a rectifier circuit configured to generate a DC voltage and a DC current based on the power signal, a regulator circuit configured to perform a conversion operation based on the DC voltage and the DC current to generate an output voltage, an impedance control circuit disposed between the rectifier circuit and the regulator circuit, and configured to perform an operation of changing the DC current, and a coupling coefficient estimator configured to calculate an estimated coupling coefficient value between the coil and an external coil based on the DC current and a load impedance corresponding to the DC current.

Description

[0001] This application claims priority and benefits to Korean Patent Application No. 10-2025-0057534, filed on April 30, 2025, with the Korean Intellectual Property Office, the entire contents of which are incorporated herein by reference. Technical Field

[0002] This disclosure relates to an electronic device, a method of operating the electronic device, and a wireless charging system. Background Technology

[0003] With the increasing use of electronic devices in various fields, charging technologies for powering these devices are being researched in various ways, including wireless charging methods that charge electronic devices without connecting a separate charging connector. Wireless charging technology uses wireless power transmission and reception, and as an example, there exists a system in which the battery of an electronic device can be automatically charged simply by placing it on a charging pad.

[0004] Wireless charging technologies include electromagnetic induction methods, resonant methods using resonance, or radio wave radiation (RF / microwave radiation) methods that convert electrical energy into microwaves and transmit them.

[0005] Wireless charging technology based on electromagnetic induction or resonance methods is a method of transmitting power between the coil of a transmitter device and the coil of a receiver device. The transmitter device generates a magnetic field, and the receiver device generates energy by inducing current based on changes in the magnetic field or by causing the current to resonate.

[0006] However, if the coils of the transmitter and receiver are not properly aligned, the coupling coefficient between the coils becomes low, which reduces AC efficiency and causes heat generation, resulting in deterioration of charging efficiency due to heat generation and other factors. Summary of the Invention

[0007] Some embodiments provide electronic devices, methods for operating electronic devices, and wireless charging systems that cost-effectively enable optimal alignment between the coils of a power transmitter device and the coils of a power receiver device.

[0008] Some embodiments provide electronic devices for easily estimating the coupling coefficient between the coil of a power transmitter device and the coil of a power receiver device, methods for operating electronic devices, and wireless charging systems.

[0009] According to a disclosed embodiment, an electronic device includes: an LC circuit including a coil and a first capacitor, configured to receive an electrical signal through induction of the coil; a rectifier circuit configured to generate a DC voltage and a DC current based on the electrical signal; a regulator circuit configured to perform a conversion operation based on the DC voltage and DC current to generate an output voltage; an impedance control circuit disposed between the rectifier circuit and the regulator circuit, configured to perform an operation to change the DC current; and a coupling coefficient estimator configured to calculate an estimated coupling coefficient value between the coil and an external coil based on the DC current and a load impedance corresponding to the DC current.

[0010] According to a disclosed embodiment, a method of operating an electronic device includes: detecting the proximity of an external electronic device based on a ping phase; performing a rectification operation on a power signal received from the external electronic device to generate a DC current flowing to a rectifier node of the electronic device and a DC voltage applied to the rectifier node; sending a control error packet to the external electronic device to maintain the reception conditions of the power signal received by the LC circuit of the electronic device from the external electronic device; changing the DC current to measure a plurality of load impedances at the output terminals of the LC circuit; calculating an estimated coupling coefficient value between an external coil in the external electronic device and an internal coil in the LC circuit based on the plurality of load impedances; comparing the estimated coupling coefficient value with a threshold; and sending negative feedback regarding the alignment between the external coil and the internal coil to a user interface of the electronic device in response to the estimated coupling coefficient value being less than the threshold.

[0011] According to a disclosed embodiment, a wireless charging system includes: a first electronic device comprising: a power source configured to provide an input voltage; a first LC circuit including a first coil and a first capacitor and configured to transmit a first power signal corresponding to the input voltage via induction of the first coil; and a demodulation circuit configured to generate a demodulated signal including a data packet for the first power signal; and a second electronic device comprising: a second LC circuit including a second coil and a second capacitor and configured to receive a second power signal corresponding to the first power signal via mutual inductance of the first coil and the second coil; a rectifier circuit configured to generate a DC voltage and a DC current based on the second power signal; an impedance control circuit configured to perform an operation to change the DC current; a controller configured to generate a control error packet requesting to maintain the input voltage before the operation to change the DC current; and a modulation circuit configured to perform a modulation operation on the control error packet using the second power signal.

[0012] According to a disclosed embodiment, a method of operating an electronic device includes: detecting the proximity of an external electronic device based on a ping phase; receiving a control error packet from the external electronic device to maintain the transmission conditions of a power signal sent to the external electronic device via an LC circuit of the electronic device; receiving an estimated coupling coefficient value between an external coil in the external electronic device and an internal coil in the LC circuit; comparing the estimated coupling coefficient value with a threshold; and moving the internal coil in response to the estimated coupling coefficient value being less than the threshold.

[0013] According to a disclosed embodiment, an electronic device includes: a pad unit including a coil and a capacitor, and configured to transmit a power signal as an AC signal through induction of the coil; an inverter circuit configured to receive an input voltage as a DC voltage from a power source and generate the power signal based on the input voltage; a demodulation circuit configured to demodulate a voltage applied across the coil to generate a demodulated signal; and a controller configured to receive a control error packet for the input voltage and an estimated coupling coefficient value of the coil from an external device via the demodulated signal, maintain the magnitude of the input voltage based on the control error packet, and move the coil within the pad unit based on the estimated coupling coefficient value. Attached Figure Description

[0014] Figure 1 This is a block diagram illustrating a wireless charging system according to some example embodiments.

[0015] Figure 2 This is a block diagram illustrating a PMIC (Power Management Integrated Circuit) according to some example embodiments.

[0016] Figure 3 This is a diagram illustrating an example of an electronic device in a wireless charging system according to some example embodiments.

[0017] Figure 4 This is a circuit diagram illustrating a wireless charging system according to some example embodiments.

[0018] Figure 5 This is a diagram illustrating the modeling of a wireless charging system in the frequency domain based on some example embodiments.

[0019] Figure 6 and Figure 7 This is a diagram used to explain the received power signals according to some example embodiments.

[0020] Figure 8 This is a flowchart illustrating a method of operating an electronic device according to some example embodiments.

[0021] Figure 9 , Figure 10 and Figure 11This is a diagram used to explain a method of operating an electronic device according to some example embodiments.

[0022] Figure 12 This is a timing diagram used to explain a method of operating an electronic device according to some example embodiments.

[0023] Figure 13 This is a timing diagram used to explain a method of operating an electronic device according to some example embodiments.

[0024] Figure 14 This is a flowchart illustrating a method of operating an electronic device according to some example embodiments.

[0025] Figures 15 to 16 This is a diagram used to explain a method of operating an electronic device according to some example embodiments. Detailed Implementation

[0026] In the following, various embodiments of the present disclosure will be described in detail with reference to the accompanying drawings to enable those skilled in the art to readily implement the embodiments. The present disclosure may be implemented in many different forms and is not limited to the embodiments described herein.

[0027] For the sake of clarity in describing this disclosure, parts that are not relevant to the description have been omitted, and the same or similar reference numerals have been assigned to the same or similar components throughout the specification.

[0028] Furthermore, throughout the specification, when a particular section “includes” a particular component, it indicates that other components may also be included, rather than excluding other components, unless otherwise specified.

[0029] Furthermore, even if a specific number is explicitly referenced in a claim, the specific number recited in a claim should not be construed as a limitation on a specific number in a claim in which such a number is not present. For example, for ease of understanding, the phrases "at least one" and "one or more" may be included in subsequent dependent claims. However, the use of these phrases should not be construed as a limitation on the indefinite article "a" or "an" described in an example.

[0030] Furthermore, when using conventions such as "at least one of A, B, or C," those skilled in the art will readily understand that the phrase (i.e., "a system comprising at least one of A, B, or C") includes the meaning of A alone, B alone, C alone, A and B, A and C, B and C, and / or A, B, and C together, but is not limited to any one of these concepts) or, in the detailed description, claims, or drawings, words and / or phrases containing two or more separate optional terms should be considered to have the possibility of including one or both of the two terms. For example, the phrase "A or B" should be understood to include the possibility of "A," or "B," or "A and B."

[0031] It will be understood that although the terms first and / or primary, second and / or secondary, third and / or tertiary, etc., may be used herein to describe various elements, components, regions, layers, and / or portions, these elements, components, regions, layers, and / or portions should not be limited by these terms. Such terms may include, for example, but not limited to, "first," "primary first," "secondary first," "second," "primary second," "secondary second," etc. Unless the context otherwise requires, these terms are used only to distinguish one element, component, region, layer, or portion from another (e.g., as a naming convention). Furthermore, in certain cases, even if the terms first and / or primary, second and / or secondary, etc., are not used in the specification, they may still be referred to as first and / or primary, second and / or secondary in the claims in order to distinguish different claimed elements from each other.

[0032] As used in this document, terms such as “block,” “module,” “unit,” and “component” are terms used to refer to components that perform at least one function or operation, and such components may be implemented in hardware or software, or a combination of hardware and software. Those skilled in the art will understand that these blocks, modules, units, and / or components are physically implemented by electronic (or optical) circuits (such as logic circuits, discrete components, microprocessors, hardwired circuits, memory elements, wiring connections, etc.) that can be formed using semiconductor-based manufacturing techniques or other manufacturing techniques. Where blocks, modules, units, and / or components are implemented by microprocessors, etc., they may be programmed using software (e.g., microcode) to perform the various functions discussed herein, and may optionally be driven by firmware and / or software. Optionally, each block, module, unit, and / or component may be implemented by dedicated hardware, or as a combination of dedicated hardware performing some functions and processors performing other functions (e.g., one or more programmed microprocessors and associated circuitry). Furthermore, without departing from the scope of the inventive concept, each block, module, unit, and / or component of an embodiment may be physically divided into two or more interactive and discrete blocks, modules, units, and / or components. Furthermore, without departing from the scope of the inventive concept, the blocks, modules, units and / or components of the embodiments can be physically combined into more complex blocks, modules, units and / or components.

[0033] Figure 1 This is a block diagram illustrating a wireless charging system according to some example embodiments. Figure 2 This is a block diagram illustrating a PMIC according to some example embodiments. Figure 3 This is a diagram illustrating an example of an electronic device in a wireless charging system according to some example embodiments.

[0034] Reference Figure 1 and Figure 2 The wireless charging system 1 may include a first electronic device 10 and a second electronic device 20. The first electronic device 10 and the second electronic device 20 are capable of wirelessly transmitting and receiving power. According to some embodiments, the first electronic device 10 can wirelessly transmit power signals to the second electronic device 20. According to some embodiments, information related to wireless power transmission / reception operations from the second electronic device 20 can be provided to the first electronic device 10 via the transmitted and received power signals.

[0035] The first electronic device 10 may be a power transmitter device (or transmitter device) and can transmit power through the induction of a coil. The first electronic device 10 may include a coil that generates an induced magnetic field through an induction process when current flows. The process by which the first electronic device 10 generates the induced magnetic field can be interpreted as the first electronic device 10 wirelessly transmitting a power signal. Furthermore, the second electronic device 20 may be a power receiver device (or receiver device) and can receive power through the induction of a coil. The second electronic device 20 may include a coil that generates an induced electromotive force (e.g., current, voltage, and / or power) through an induced magnetic field generated nearby, according to an induction method or a resonance method. The process by which the second electronic device 20 generates an induced electromotive force through an ambient magnetic field can be interpreted as the second electronic device 20 wirelessly receiving a power signal. According to some embodiments, the first electronic device 10 and the second electronic device 20 may implement at least a portion of the methods defined in the WPC (Wireless Power Consortium) Qi standard.

[0036] According to some embodiments, the first electronic device 10 can perform communication with the second electronic device 20. For example, the first electronic device 10 can perform communication with the second electronic device 20 according to an in-band method. The first electronic device 10 can modulate data (or packets) to be transmitted to the second electronic device 20 according to, for example, an FSK (Frequency Shift Keying) modulation method, and the second electronic device 20 can provide data (or packets) to the first electronic device 10 by performing modulation according to an ASK (Amplitude Shift Keying) modulation method. The first electronic device 10 can check the data provided by the second electronic device 20 based on the amplitude of the current and / or voltage applied to the coil. According to some embodiments, the second electronic device 20 can control the closing / opening of at least one internal switch to transmit data to the first electronic device 10. For example, the second electronic device 20 can control the operation of at least one internal switch to transmit data to the first electronic device 10. Modulation operations based on ASK modulation methods and / or FSK modulation methods can be understood as data transmission operations according to in-band communication methods, and demodulation operations based on ASK demodulation methods and / or FSK demodulation methods can be understood as data reception operations according to in-band communication methods.

[0037] According to some embodiments, based on the protocol defined in the WPC Qi standard, the first electronic device 10 can send power to the second electronic device 20 through a ping phase, a configuration phase, a negotiation phase for the power transmitter and power receiver to negotiate the wireless charging power level and other necessary information for charging, and a power transmission phase.

[0038] The first electronic device 10 may include a power supply 11, an inverter circuit 13, a pad unit 14, a demodulation circuit 15, and a transmitter controller 16.

[0039] The transmitter controller 16 controls the overall operation related to wireless charging of the first electronic device 10. The transmitter controller 16 can provide a voltage control signal Vctrl to the power supply 11, a first switch enable signal SW_EN1 to the inverter circuit 13, and a position control signal Lctrl to the pad unit 14, thereby controlling the components in the first electronic device 10.

[0040] According to some embodiments, the transmitter controller 16 may be an MCU (microcontroller unit), FPGA (field programmable gate array), ASIC (application-specific integrated circuit), microprocessor, or AP (application processor), but is not limited to these examples.

[0041] Power supply 11 can provide input voltage VIN to inverter circuit 13 based on voltage control signal Vctrl from transmitter controller 16. According to some embodiments, input voltage VIN can be a DC voltage. Power supply 11 may include at least one of an interface for connection to an external TA travel adapter, a battery (not shown) of the first electronic device 10, a charger (not shown), and / or a PMIC (not shown). Power supply 11 can provide DC power to inverter circuit 13, but is not limited thereto, and according to embodiments, the input voltage VIN generated by power supply 11 can be converted by a DC / DC converter (DC-DC conversion circuit) and provided to inverter circuit 13. According to some embodiments, there is no limitation on the amount of power provided via input voltage VIN.

[0042] Inverter circuit 13 can provide a first power signal PS1 to pad unit 14 using input voltage VIN. According to some embodiments, inverter circuit 13 includes multiple switches, and the multiple switches can correspond to... Figure 4 The inverter circuit 13 can implement a full-bridge circuit by using first-stage first switches SW11 to fourth-stage first switches SW14, but the number of switches or the type of circuit is not limited. The inverter circuit 13 can receive a first switch enable signal SW_EN1 from the transmitter controller 16 and generate a first power signal PS1 by switching operations based on the first switch enable signal SW_EN1. According to an embodiment, the first power signal PS1 generated by the switching operation can be a rectangular wave signal in AC form. According to some embodiments, the presence or absence of the output of the first power signal PS1 can be controlled based on the first switch enable signal SW_EN1, or the frequency of the first power signal PS1 can be adjusted. According to an embodiment, the frequency of the first power signal PS1 can be from 100kHz to 370kHz.

[0043] The pad unit 14 may include a transmitter LC circuit LC1, which includes a coil and a capacitor. An LC circuit (also referred to as an LC resonant circuit or LC oscillating circuit) is a circuit that includes an inductor (L) and a capacitor (C). According to some embodiments, the coil and capacitor in the transmitter LC circuit LC1 may be connected in series or in parallel with each other within the pad unit 14 depending on the power transmission method. The coil in the transmitter LC circuit LC1 may correspond to... Figure 3 and Figure 4 The transmitter coil Lp, and the capacitor in the transmitter LC circuit LC1 can correspond to Figure 4 The transmitter capacitor Cp. The pad unit 14 can receive a first power signal PS1 from the inverter circuit 13, and the first power signal PS1 can be provided to the coil in the transmitter LC circuit LC1.

[0044] When the first power signal PS1, as an AC signal, is supplied to the coil of the transmitter LC circuit LC1, the receiver coil Ls of the adjacent receiver LC circuit LC2 and the coil of the transmitter LC circuit LC1 (e.g., Figure 3 The transmitter coils Lp and Ls can induce each other. During this mutual inductance, the coil of the transmitter LC circuit LC1 can generate a magnetic field based on a first electrical signal PS1, which is an AC signal. A portion of the magnetic field (or magnetic flux) generated by the coil of the transmitter LC circuit LC1 can pass through the cross-section of the receiver coil Ls. As the magnetic field passing through the cross-section of the receiver coil Ls changes over time, an induced electromotive force (e.g., current, voltage, or power) can be generated in the receiver coil Ls. Through this mutual inductance, the transmitter LC circuit LC1 can transmit the first electrical signal PS1, and the receiver LC circuit LC2 can receive a second electrical signal PS2 corresponding to the first electrical signal PS1. According to an embodiment, the second electrical signal PS2 can resemble a rectangular wave signal in AC form, and the frequency of the signal in the first electrical signal PS1 and the frequency of the signal in the second electrical signal PS2 can be the same. According to some embodiments, the resonant frequencies of the transmitter LC circuit LC1 and the receiver LC circuit LC2 can be substantially the same as the frequencies of the first electrical signal PS1 and the second electrical signal PS2.

[0045] The degree of mutual inductance is proportional to the coupling coefficient k between the two coils, and the power transmission efficiency can vary depending on the magnitude of the coupling coefficient k. The coupling coefficient k represents the ratio of magnetic flux passing through the two coils, and the coupling coefficient k can vary depending on at least one of the following: the alignment state between the coils, the distance between the coils, the presence of foreign objects between the coils, and the size of the coils. In this disclosure, the coupling coefficient k will be described under the premise that it varies according to the alignment state between the coils, which is one of the reasons for the aforementioned variation.

[0046] According to some embodiments, pad unit 14 can move the coil of transmitter LC circuit LC1 based on a position control signal Lctrl. Transmitter controller 16 can repeatedly receive an estimated coupling coefficient value k_est calculated by second electronics 20, and can provide the position control signal Lctrl to pad unit 14 based on the estimated coupling coefficient value k_est. In the direction in which the coupling coefficient k between the coil of transmitter LC circuit LC1 and receiver coil Ls increases, the coil of transmitter LC circuit LC1 can move within the housing of pad unit 14 based on the position control signal Lctrl. For example, transmitter controller 16 can determine the position where the coupling coefficient k between the coil of transmitter LC circuit LC1 and receiver coil Ls is increasing, and transmitter controller 16 can send the position control signal Lctrl to transmitter LC circuit LC1 such that the coil of transmitter LC circuit LC1 moves within the housing of pad unit 14 based on the received position control signal Lctrl.

[0047] The demodulation circuit 15 can demodulate the signal applied to the coil of the transmitter LC circuit LC1 and output a demodulated signal Vdemod. The demodulation circuit 15 can output the demodulated signal Vdemod by down-converting the signal applied to the coil (e.g., the voltage across its terminals) to the frequency of the first power signal PS1 (e.g., 100kHz to 370kHz). For example, the demodulation circuit 15 can generate a demodulated signal Vdemod that includes a data packet for the first power signal PS1. For example, the demodulation circuit 15 may include a mixer and / or multiplier circuit for removing the carrier signal component (e.g., the frequency of the first power signal PS1) used for wireless power transmission. Here, since the waveform of the modulated component of the second electronic device 20 mixed with the first power signal PS1 can be applied to the coil of the transmitter LC circuit LC1, the frequency component of the first power signal PS1 is referred to as the carrier signal component, and those skilled in the art will understand that the second electronic device 20 does not actually generate the carrier and electromagnetic wave by modulating the receiver data RD. According to some embodiments, the demodulation circuit 15 may include a low-pass filter and may filter the demodulation signal Vdemod before outputting the demodulation signal Vdemod (low-pass filtered). Optionally, the demodulation circuit 15 may filter the terminals of the coil of the transmitter LC circuit LC1 and then down-convert it to the frequency of the first power signal PS1 to generate the demodulation signal Vdemod. The voltage amplitude across the coil of the transmitter LC circuit LC1 may fluctuate according to the ASK modulation of the second electronic device 20.

[0048] According to some embodiments, the transmitter controller 16 may receive receiver data RD provided by the second electronic device 20 based on a demodulation signal Vdemod generated by the demodulation circuit 15. The transmitter controller 16 may perform an ADC (analog-to-digital conversion) operation on the demodulation signal Vdemod. The transmitter controller 16 may decode the digital value generated by the ADC operation and receive the receiver data RD provided by the second electronic device 20 based on the decoding result. The decoding method may be, for example, according to the Qi standard, but is not limited thereto. Meanwhile, in the above embodiments, it is described that the demodulation circuit 15 performs down-conversion (e.g., carrier removal and / or low-pass filtering), and the transmitter controller 16 performs ADC operation and / or decoding; however, this is merely exemplary. Those skilled in the art will understand that the demodulation circuit 15 may be implemented to further perform at least one of ADC operation and / or decoding, and the transmitter controller 16 may be implemented to further perform down-conversion (e.g., carrier removal and / or low-pass filtering).

[0049] The second electronic device 20 may include a processor 21, a memory 22, a user interface 23, a receiver LC circuit LC2, a PMIC 24, a charger 26, and a battery 27. The processor 21, memory 22, user interface 23, PMIC 24, and charger 26 may be electrically connected and / or operatively connected to each other via electronic components (such as a communication bus 28).

[0050] Processor 21 may include hardware and / or circuitry for processing data based on one or more instructions. The hardware and / or circuitry for processing data may include, for example, an ALU (Arithmetic and Logic Unit), an FPU (Floating-Point Unit), a CPU (Central Processing Unit), an FPGA, and / or an AP. The number of processors 21 may be one or more. For example, processor 21 may have a multi-core processor architecture such as dual-core, quad-core, hexa-core, or octa-core.

[0051] The processor 21 can control the overall operation of the second electronic device 20, and control the operation of components within the second electronic device 20 by providing commands to the components. (See reference...) Figure 2 As an example, processor 21 can provide command CMD to PMIC 24 to control the output voltage Vout and output current Iout output from PMIC 24. Controller 241 of PMIC 24 can, in response to receiving command CMD, provide regulator control signal DCctrl to regulator circuit 244 to control the operating current Io, output voltage Vout, and output current Iout of regulator circuit 244.

[0052] Memory 22 may include hardware configurations for storing data and / or instructions input to and / or output from processor 21. Memory 22 may include, for example, volatile memory such as RAM (Random Access Memory) and / or non-volatile memory such as ROM (Read Only Memory). Volatile memory may include at least one of, for example, DRAM (Dynamic RAM), SRAM (Static RAM), cache RAM, and PSRAM (Pseudo SRAM). Non-volatile memory may include at least one of, for example, PROM (Programmable ROM), EPROM (Erasable PROM), EEPROM (Electrically Erasable PROM), flash memory, hard disk, optical disk, SSD (Solid State Drive), and / or eMMC (Embedded Multimedia Card).

[0053] User interface 23 may include one or more displays, speakers, haptic engines, vibrators, or any other output devices. Furthermore, according to embodiments, user interface 23 may include a pen, touch input device, camera, voice input device, video input device, keyboard, mouse, or any other input device. According to some embodiments, user interface 23 may display the status of the second electronic device 20 based on the control of processor 21.

[0054] Reference Figure 2 and Figure 3 As an example, processor 21 may receive alignment feedback data (FBD) from PMIC 24. Based on the alignment feedback data FBD, processor 21 may control the display 231 of user interface 23 to display the alignment status with the coil of the first electronic device 10. The second electronic device 20 may inform the user of the alignment status between the coils through the display operation of display 231, and may prompt the user to adjust the alignment status between the first electronic device 10 and the second electronic device 20.

[0055] Reference Figure 2 and Figure 4 The receiver LC circuit LC2 can be connected to the PMIC 24 and may include a receiver coil Ls, a receiver capacitor Cs, and a receiver resistor Rs. The receiver LC circuit LC2 may have an equivalent impedance value of the receiver impedance Zs. According to some embodiments, the receiver coil Ls may correspond to... Figure 3 The receiver coil Ls. According to some embodiments, the receiving resistor Rs is the parasitic resistance of the receiver coil Ls, and the connection relationship between the receiver coil Ls and the receiver capacitor Cs in the receiver LC circuit LC2 can vary depending on the power transmission method.

[0056] The receiver LC circuit LC2 can perform narrowband filtering centered on the resonant frequency. According to some embodiments, the resonant frequency of the receiver LC circuit LC2 can be substantially the same as the frequency of the second power signal PS2.

[0057] The receiver coil Ls can receive the second electrical signal PS2 based on the mutual inductance between the coil of the transmitter LC circuit LC1 and the coupling coefficient k, and provide it to the PMIC 24. According to an embodiment, the second electrical signal PS2 can be an AC electrical signal.

[0058] PMIC 24 rectifies and frequency-converts the second power signal PS2 received from the receiver LC circuit LC2, and provides the output voltage Vout and output current Iout to charger 26. Charger 26 charges battery 27 based on the power supplied from PMIC 24. Charger 26 can control the voltage and / or current used to charge battery 27 according to the charging mode of battery 27 (e.g., constant current (CC) mode, constant voltage (CV) mode, or fast charging mode). According to some embodiments, battery 27 may include a rechargeable secondary battery or a fuel cell.

[0059] PMIC 24 can estimate the coupling coefficient k between the coil of the transmitter LC circuit LC1 and the coil of the receiver LC circuit LC2 to calculate the estimated coupling coefficient value k_est. PMIC 24 can provide alignment feedback data FBD regarding the alignment state between the coils of the transmitter LC circuit LC1 and the receiver LC circuit LC2 based on the estimated coupling coefficient value k_est, or it can perform a modulation operation based on the estimated coupling coefficient value k_est to send the estimated coupling coefficient value k_est to the first electronic device 10. During the calculation of the estimated coupling coefficient value k_est, the load impedance Zload at the output terminal of the receiver LC circuit LC2 can fluctuate. In this disclosure, the load impedance Zload can represent the equivalent impedance value of the portion of the second electronic device 20 excluding the receiver LC circuit LC2.

[0060] Furthermore, under the control of the processor 21, the PMIC 24 can provide power obtained from the battery 27 to each of the hardware components (e.g., processor 21, memory 22, user interface 23, and / or PMIC 24) within the second electronic device 20.

[0061] The PMIC 24 may include a controller 241, a rectifier circuit 242, a resistive impedance control circuit (or impedance control circuit) 243, a regulator circuit 244, a modulation circuit (or ASK modulation circuit) 245, a load impedance measurement unit 246, and a coupling coefficient estimator unit 247.

[0062] Controller 241 controls the overall operation of PMIC 24. Controller 241 receives commands (CMD) from processor 21 and controls components within PMIC 24 based on these commands. Controller 241 can provide a second switch enable signal SW_EN2 to rectifier circuit 242, a first impedance control signal Ictrl1 to resistive impedance control circuit 243, a regulator control signal DCctrl to regulator circuit 244, and a second impedance control signal Ictrl2 to modulation circuit 245 to control components within PMIC 24. Furthermore, controller 241 can provide receiver data RD to modulation circuit 245 to control modulation circuit 245 to communicate with second electronic device 20 in an in-band manner. According to some embodiments, receiver data RD may include power receiver data packets defined in the WPC Qi standard.

[0063] The controller 241 may receive an estimated coupling coefficient value k_est from the coupling coefficient estimator unit 247 and compare the estimated coupling coefficient value k_est with a predetermined threshold. Based on the comparison operation of the estimated coupling coefficient value k_est, the controller 241 may provide alignment feedback data FBD regarding the alignment state between the coil of the transmitter LC circuit LC1 and the coil of the receiver LC circuit LC2 to the processor 21. Furthermore, the controller 241 may provide receiver data RD corresponding to the estimated coupling coefficient value k_est to the modulation circuit 245, thereby performing a modulation operation for the estimated coupling coefficient value k_est.

[0064] According to some embodiments, controller 241 may be an MCU, FPGA, ASIC, microprocessor, or AP, but is not limited to these examples.

[0065] The rectifier circuit 242 can be electrically connected to the output terminal of the receiver LC circuit LC2. The rectifier circuit 242 can perform a rectification operation on the second power signal PS2 received through the receiver LC circuit LC2 to generate a rectified voltage Vrect as a DC voltage and a rectified current Irect as a DC current. According to some embodiments, the rectifier circuit 242 may include a plurality of switches, and the plurality of switches may correspond to... Figure 4 The first-stage second switch SW21 to the fourth-stage second switch SW24. The rectifier circuit 242 can receive the second switch enable signal SW_EN2 from the controller 241, and generate the rectified voltage Vrect and rectified current Irect by switching operations based on the second switch enable signal SW_EN2.

[0066] The regulator circuit 244 can generate an output voltage Vout and an output current Iout by performing a conversion operation (e.g., buck conversion, boost conversion, low-dropout regulation, etc.) and / or a regulation operation on the rectified voltage Vrect output from the rectifier circuit 242. The regulator circuit 244 can receive an operating current Io during the conversion and regulation operations, and the operating current Io can be at least a portion of the rectified current Irect. According to some embodiments, the output voltage Vout and the output current Iout can be controlled by a regulator control signal DCctrl, and the magnitude of the operating current Io can also be adjusted by the regulator control signal DCctrl. According to some embodiments, the magnitude of the rectified current Irect can also fluctuate due to fluctuations in the operating current Io.

[0067] A resistive impedance control circuit 243 may be disposed between the rectifier circuit 242 and the regulator circuit 244, and may receive a resistive impedance regulation current Ira based on a first impedance control signal Ictrl1. According to some embodiments, the resistive impedance regulation current Ira may be at least a portion of the rectified current Irect, and the magnitude of the rectified current Irect may also fluctuate according to fluctuations in the resistive impedance regulation current Ira. According to some embodiments, the resistive impedance control circuit 243 may include a variable resistor and / or a variable current source, but is not limited thereto. According to some embodiments, when the resistive impedance control circuit 243 performs an operation to change the rectified current Irect, the magnitude of the second power signal PS2 may be maintained.

[0068] According to some embodiments, as the rectified current Irect fluctuates due to fluctuations in the operating current Io and the resistive impedance regulation current Ira, the rectified voltage Vrect can fluctuate, and the load impedance Zload at the output terminal of the receiver LC circuit LC2 can also fluctuate.

[0069] Modulation circuit 245 may perform modulation operation using an ASK modulation method in response to receiver data RD. According to some embodiments, receiver data RD may include an estimated coupling coefficient value k_est, a control error packet in a power receiver data packet requesting adjustment of the input voltage VIN of the first electronic device 10, etc. For example, modulation circuit 245 may use a second power signal PS2 to perform modulation operation on the control error packet.

[0070] According to some embodiments, modulation circuit 245 may include a plurality of capacitors and a switch controlling the connection between the plurality of capacitors and the output terminal of receiver LC circuit LC2. Modulation circuit 245 may select the capacitor to be modulated from the plurality of capacitors based on receiver data RD. The modulation capacitance of modulation circuit 245 connected to the output terminal of receiver LC circuit LC2 fluctuates according to the selected capacitor, and the difference in amplitude of the voltage applied to transmitter LC circuit LC1 can be adjusted.

[0071] Although not shown in the accompanying drawings, according to an embodiment, receiver data RD may be encoded and then provided to modulation circuit 245.

[0072] The modulation circuit 245 can control the connection between the output terminal of the receiver LC circuit LC2 and the capacitor based on the second impedance control signal Ictrl2 provided from the controller 241. In response to the connection between the output terminal of the receiver LC circuit LC2 and the capacitor, the reactance component of the load impedance Zload can fluctuate.

[0073] The load impedance measurement unit 246 can measure the load impedance Zload based on the rectified voltage Vrect and rectified current Irect generated from the rectifier circuit 242. According to some embodiments, the load impedance measurement unit 246 may include a voltage measurement circuit monitoring the rectified voltage Vrect and a current measurement circuit monitoring the rectified current Irect, and can measure the load impedance Zload based on the measured rectified voltage Vrect and the measured rectified current Irect, but is not limited thereto. According to some embodiments, the load impedance measurement unit 246 can receive the values ​​of the rectified voltage Vrect and the rectified current Irect, and can measure the load impedance Zload based on information about the rectified voltage Vrect and the rectified current Irect. According to some embodiments, the load impedance measurement unit 246 can be configured as a dedicated circuit in hardware, but is not limited thereto, and when the load impedance measurement unit 246 is configured as software, it can be implemented through software execution by the controller 241.

[0074] The coupling coefficient estimator unit 247 can receive the rectified current Irect and the load impedance Zload corresponding to the rectified current Irect from the load impedance measurement unit 246. Furthermore, the coupling coefficient estimator unit 247 can receive the rectified voltage Vrect and a predetermined receiving impedance Zs. The coupling coefficient estimator unit 247 can calculate an estimated coupling coefficient value k_est based on multiple rectified currents Irect, multiple load impedances Zload, the receiving impedance Zs, and reactance information. The estimated coupling coefficient value k_est calculated by the coupling coefficient estimator unit 247 can be provided to the controller 241. The reactance information can be confirmed based on the fluctuation of the rectified voltage Vrect, and can be the polarity of the reactance component of the total input impedance viewed from the second electronic device 20.

[0075] exist Figure 2The diagram shows that the coupling coefficient estimator unit 247 receives the rectified voltage Vrect and the rectified current Irect from the load impedance measurement unit 246, but it is not limited thereto. According to the embodiment, the coupling coefficient estimator unit 247 may directly measure the rectified voltage Vrect and the rectified current Irect or receive these values ​​as data.

[0076] According to some embodiments, the coupling coefficient estimator unit 247 can calculate an estimated coupling coefficient value k_est based on three rectified currents Irect, three load impedances Zload corresponding to the three rectified currents Irect, and reactance information. According to another embodiment, the coupling coefficient estimator unit 247 can calculate an estimated coupling coefficient value k_est based on three rectified currents Irect and three load impedances Zload corresponding to the three rectified currents Irect. According to yet another embodiment, the coupling coefficient estimator unit 247 can calculate an estimated coupling coefficient value k_est based on two rectified currents Irect and two load impedances Zload corresponding to the two rectified currents Irect.

[0077] According to some embodiments, the coupling coefficient estimator unit 247 may be configured as a dedicated circuit in hardware form, but is not limited thereto, and when the coupling coefficient estimator unit 247 is configured as software form, the coupling coefficient estimator unit 247 may be implemented by software execution of the controller 241.

[0078] The second electronic device 20 can measure multiple load impedances Zload corresponding to multiple rectified currents Irect by changing the rectified current Irect through the resistive impedance control circuit 243, and can calculate the estimated coupling coefficient value k_est between the coil of the first electronic device 10 and the coil of the second electronic device 20 through the multiple rectified currents Irect and the multiple load impedances Zload.

[0079] The second electronic device 20 can perform the display operation of the user interface 23 based on the estimated coupling coefficient value k_est, so that the user is aware of the alignment status between the coils. The second electronic device 20 can prompt the user to adjust the alignment status between the first electronic device 10 and the second electronic device 20 without the need for individual components (such as magnets for coil alignment).

[0080] Furthermore, the second electronic device 20 can repeatedly send the estimated coupling coefficient value k_est to the first electronic device 10 to move the coil of the first electronic device 10 in the direction that increases the coupling coefficient k between the coil of the first electronic device 10 and the coil of the second electronic device 20. By moving the coil in the first electronic device 10, the second electronic device 20, as a power receiver device, can cost-effectively facilitate optimal alignment between the coils without the need for separate components (such as magnets for alignment).

[0081] Figure 3 This is a diagram illustrating an example of an electronic device in a wireless charging system according to some example embodiments.

[0082] Reference Figure 3 The first electronic device 10 can be a wireless charging device. The pad unit 14 is positioned adjacent to the outer surface of the first electronic device 10, and the transmitter coil Lp can be disposed within the housing of the pad unit 14. The transmitter coil Lp can correspond to... Figure 1 The transmitter coil LC1 is a coil of the LC circuit. The transmitter coil Lp may be in the form of a closed loop, and although the transmitter coil Lp is shown in the figures as comprising wire wound in a spiral and / or concentric manner, this is merely an exemplary form and is not a limitation. The transmitter coil Lp may be configured to transmit or receive electrical signals.

[0083] The second electronic device 20 may be referred to as a terminal (or user terminal). Although the second electronic device 20 is a terminal... Figure 3 The device is shown as a smartphone, but is not limited thereto. The terminal may include, for example, a smart tablet and / or a tablet PC, and may include smart accessories (such as smartwatches and / or HMD headsets). The terminal may include implantable devices (e.g., pacemakers, insulin pumps, and / or cochlear implants). Embodiments are not limited thereto, and the terminal may include, for example, a personal computer PC (such as laptops and desktop computers).

[0084] The receiver coil Ls can be configured to be adjacent to one surface (e.g., the rear surface) of the second electronic device 20, or it can be configured on another surface inside the second electronic device 20 that is parallel to or opposite to one surface (e.g., the rear surface). The receiver coil Ls can correspond to Figure 1 and Figure 2The receiver coil Ls of the receiver LC circuit LC2. The receiver coil Ls may be disposed on another surface opposite to the surface on which the display 231 is disposed (e.g., the front surface of the second electronic device 20) (i.e., disposed on the inner surface of the housing forming the appearance). According to some embodiments, the receiver coil Ls may be included in an FPCB (flexible printed circuit board) and / or PCB (printed circuit board) adjacent to the rear surface of the second electronic device 20. According to some embodiments, the receiver coil Ls may be in the form of a closed loop, and although the receiver coil Ls is shown in the drawings as comprising wires wound in a spiral and / or concentric manner, this is merely an exemplary form and not a limitation thereof. The receiver coil Ls may be configured to transmit or receive electrical signals.

[0085] The second electronic device 20 can be mounted on the outer surface of the first electronic device 10 adjacent to the pad unit 14. By arranging the pad unit 14 in the first electronic device 10, the first electronic device 10 can reduce the distance between the transmitter coil Lp and the receiver coil Ls and increase the coupling coefficient k with the receiver coil Ls. With the arrangement of the pad unit 14 as described above, the transmitter coil Lp and the receiver coil Ls can be mutually inducted based on a relatively large coupling coefficient k.

[0086] The second electronic device 20 can perform the display operation of the display 231 based on the estimated coupling coefficient value k_est, so that the user knows the alignment state between the transmitter coil Lp and the receiver coil Ls. The second electronic device 20 can prompt the user to adjust the alignment state between the first electronic device 10 and the second electronic device 20 without the need for separate components (such as magnets for coil alignment).

[0087] Furthermore, the transmitter coil Lp can move in response to an estimated coupling coefficient value k_est received from the second electronic device 20. The second electronic device 20 can repeatedly send the estimated coupling coefficient value k_est to the first electronic device 10 to move the transmitter coil Lp in the direction that increases the coupling coefficient k between the transmitter coil Lp and the receiver coil Ls. By moving the transmitter coil Lp, the second electronic device 20, as a power receiver device, can cost-effectively facilitate optimal alignment between the coils without the need for separate components (such as magnets for alignment).

[0088] Although the first electronic device 10 is shown in the drawings as a wireless charging device, it is not limited thereto, and according to the embodiments, the first electronic device 10 may be implemented in the form of a user terminal.

[0089] Figure 4 This is a circuit diagram illustrating a wireless charging system according to some example embodiments. Specifically, Figure 4An exemplary circuit of the wireless charging system 1 is shown. Figure 4 The first electronic device 10, power supply 11, inverter circuit 13, transmitter LC circuit LC1, second electronic device 20, receiver LC circuit LC2, rectifier circuit 242, resistive impedance control circuit 243, regulator circuit 244, and modulation circuit 245 can respectively correspond to Figure 1 and Figure 2 The first electronic device 10, power supply 11, inverter circuit 13, transmitter LC circuit LC1, second electronic device 20, receiver LC circuit LC2, rectifier circuit 242, resistive impedance control circuit 243, regulator circuit 244 and modulation circuit 245.

[0090] Reference Figure 4 The first electronic device 10 may include a power supply 11, an inverter circuit 13, and a transmitter LC circuit LC1, and the second electronic device 20 may include a receiver LC circuit LC2, a rectifier circuit 242, a resistive impedance control circuit 243, a regulator circuit 244, a modulation circuit 245, and a charger 26.

[0091] Inverter circuit 13 can output an AC signal using the input voltage VIN. Inverter circuit 13 may include multiple first switches SW11 to SW14. Figure 4 In this embodiment, multiple first switches SW11 to SW14 are arranged in the form of a full-bridge circuit, but are not limited thereto, and the number of switches or the type of circuit may vary depending on the embodiment.

[0092] The first-level switch SW11 can be controlled by the first-level switch enable signal SW_EN11, and may include one end connected to the power supply 11 and the other end connected to the first node n1.

[0093] The secondary first switch SW12 can be controlled by the secondary first switch enable signal SW_EN12, and may include one end connected to power supply 11 and the other end connected to the second node n2. The tertiary first switch SW13 can be controlled by the tertiary first switch enable signal SW_EN13, and may include one end connected to the first node n1 and the other end connected to ground. The quaternary first switch SW14 can be controlled by the quaternary first switch enable signal SW_EN14, and may include one end connected to the second node n2 and the other end connected to ground. The first node n1 between the primary first switch SW11 and the tertiary first switch SW13 is connected to one end of the transmitter LC circuit LC1, and the second node n2 between the secondary first switch SW12 and the quaternary first switch SW14 can be connected to the other end of the transmitter LC circuit LC1. The primary first switch enable signal SW_EN11 to the quaternary first switch enable signal SW_EN14 can correspond to Figure 1The first switch enable signal SW_EN1, and can be obtained from Figure 1 The transmitter controller 16 receives the signal. According to some embodiments, each of the plurality of first switches SW11 to SW14 includes a transistor and a diode, and the transistor and diode may be connected in parallel at both ends.

[0094] Multiple first switches SW11 to SW14 can be closed or opened based on the first-level first switch enable signal SW_EN11 to the fourth-level first switch enable signal SW_EN14, and an AC signal can be generated by controlling the closing operation of the multiple first switches SW11 to SW14. In a first time period, the first-level first switch SW11 and the fourth-level first switch SW14 can be closed, and the second-level first switch SW12 and the third-level first switch SW13 can be opened. In a second time period, the second-level first switch SW12 and the third-level first switch SW13 can be closed, and the first-level first switch SW11 and the fourth-level first switch SW14 can be opened. The switching operations in the first and second time periods can be repeated during the generation of AC power. Furthermore, by controlling the switching operations of the multiple first switches SW11 to SW14, the presence or absence of the AC signal output can be controlled, or the frequency of the AC signal can be adjusted.

[0095] The transmitter LC circuit LC1 can be connected to the inverter circuit 13 through the first node n1 and the second node n2, and can receive the AC signal generated in the inverter circuit 13 as a power signal to be transmitted.

[0096] The transmitter LC circuit LC1 may include a transmitter coil Lp, a transmitter capacitor Cp, and a transmitter resistor Rp, and may have an equivalent impedance value of a transmitting impedance Zp. According to some embodiments, the transmitter coil Lp may correspond to... Figure 1 The transmitter coil in the transmitter LC circuit LC1. According to some embodiments, the transmitter resistor Rp can be the parasitic resistance of the transmitter coil Lp, and the connection relationship between the transmitter coil Lp and the transmitter capacitor Cp in the transmitter LC circuit LC1 can vary depending on the power transmission method.

[0097] The transmitter coil Lp can be mutually inducted with the receiver coil Ls of the receiver LC circuit LC2 based on the coupling coefficient k, and the power signal is sent to the receiver LC circuit LC2 through the mutual inductance.

[0098] The receiver coil Ls can be mutually inducted with the transmitter coil Lp based on the coupling coefficient k. Through this mutual inductance, the receiver LC circuit LC2 can receive the power signal as an AC signal and provide it to the rectifier circuit 242. The receiver LC circuit LC2 can be connected to the rectifier circuit 242 through the third node n3 and the fourth node n4. One end of the receiver LC circuit LC2 can be connected to the fourth node n4, and the other end of the receiver LC circuit LC2 can be connected to the third node n3.

[0099] The rectifier circuit 242 can receive the AC signal received through the receiver LC circuit LC2 and convert the AC signal into a DC signal. Based on the AC signal, the rectifier circuit 242 can apply the rectified voltage Vrect to the rectifier node nr and provide the rectified current Irect to the rectifier node nr.

[0100] The rectifier circuit 242 may include multiple second switches SW21 to SW24 and a rectifier capacitor Cr. Figure 4 In this embodiment, multiple second switches SW21 to SW24 can be arranged in the form of a full-bridge circuit, but are not limited thereto, and the number of switches or the type of circuit can vary depending on the embodiment.

[0101] The first-stage second switch SW21 can be controlled by the first-stage second switch enable signal SW_EN21, and may include one end connected to the rectifier node nr and the other end connected to the fourth node n4. The second-stage second switch SW22 can be controlled by the second-stage second switch enable signal SW_EN22, and may include one end connected to the rectifier node nr and the other end connected to the third node n3. The third-stage second switch SW23 can be controlled by the third-stage second switch enable signal SW_EN23, and may include one end connected to the fourth node n4 and the other end connected to ground. The fourth-stage second switch SW24 can be controlled by the fourth-stage second switch enable signal SW_EN24, and may include one end connected to the third node n3 and the other end connected to ground. The fourth node n4 between the first-stage second switch SW21 and the third-stage second switch SW23 can be connected to one end of the receiver LC circuit LC2, and the third node n3 between the second-stage second switch SW22 and the fourth-stage second switch SW24 can be connected to the other end of the receiver LC circuit LC2. The first-stage second switch enable signal SW_EN21 to the fourth-stage second switch enable signal SW_EN24 may correspond to Figure 1 The second switch enable signal SW_EN2, and can be obtained from Figure 2 The controller 241 receives the data. According to some embodiments, each of the plurality of second switches SW21 to SW24 includes a transistor and a diode, and the transistor and diode may be connected in parallel at both ends.

[0102] Multiple second switches SW21 to SW24 can be closed or opened based on the first-level second switch enable signal SW_EN21 to the fourth-level second switch enable signal SW_EN24, and the rectified voltage Vrect and rectified current Irect as DC signals can be generated by controlling the closing operation of multiple second switches SW21 to SW24.

[0103] A rectifier capacitor Cr may be disposed between the rectifier node nr and the ground terminal, and maintain the rectified voltage Vrect at the rectifier node nr. According to some embodiments, the rectifier capacitor Cr may smooth the high-frequency components included in the rectified voltage Vrect, and may be referred to as a smoothing capacitor.

[0104] The resistive impedance control circuit 243 can receive a resistive impedance-regulated current Ira from the rectifier node nr. The resistive impedance control circuit 243 may include a variable current source 2431 disposed between the rectifier node nr and the ground terminal and / or a variable resistor 2432 disposed between the rectifier node nr and the ground terminal.

[0105] The resistive impedance control circuit 243 can change the resistive impedance regulation current Ira by controlling the current flowing in the variable current source 2431 or by adjusting the resistance value of the variable resistor 2432. This can be based on... Figure 2 The first impedance control signal Ictrl1 is used to adjust the current magnitude of the variable current source 2431 and the resistance magnitude of the variable resistor 2432. According to some embodiments, as the resistive impedance adjustment current Ira fluctuates, the rectified current Irect can fluctuate, and as the rectified current Irect fluctuates, the load impedance can fluctuate.

[0106] The regulator circuit 244 performs a conversion operation on the rectified voltage Vrect to generate an output voltage Vout and an output current Iout, and stably outputs the output voltage Vout and output current Iout. The generated output voltage Vout and output current Iout can be provided to the charger 26. The charger 26 can correspond to... Figure 1 Charger 26.

[0107] The regulator circuit 244 may include a DC-DC converter circuit 2442 and a feedback circuit 2441. The DC-DC converter circuit 2442 performs a conversion operation on the rectified voltage Vrect to generate an output voltage Vout and filters noise from the output voltage Vout. The feedback circuit 2441 senses the difference between the output voltage Vout and a reference voltage and amplifies the difference between the output voltage Vout and the reference voltage.

[0108] The regulator circuit 244 can receive an operating current Io from the rectifier node nr during conversion and amplification operations, and the operating current Io can be at least a portion of the rectified current Irect. The magnitudes of the output voltage Vout, the output current Iout, and the operating current Io can be adjusted by the regulator control signal DCctrl. According to some embodiments, as the operating current Io fluctuates, the rectified current Irect can fluctuate, and as the rectified current Irect fluctuates, the load impedance can fluctuate.

[0109] The modulation circuit 245 may include multiple modulation capacitors Ccma1, Ccma2, Ccmb1, Ccmb2 and multiple selection switches SW3a, SW4a, SW3b, SW4b.

[0110] The first-stage modulation capacitor Ccma1 may include one electrode connected to the third node n3 and another electrode connected to one end of the first-stage third selection switch SW3a.

[0111] The primary second modulation capacitor Ccmb1 may include one electrode connected to the third node n3 and another electrode connected to one end of the secondary third selection switch SW3b. The secondary first modulation capacitor Ccma2 may include one electrode connected to the fourth node n4 and another electrode connected to one end of the primary fourth selection switch SW4a. The secondary second modulation capacitor Ccmb2 may include one electrode connected to the fourth node n4 and another electrode connected to one end of the secondary fourth selection switch SW4b. According to some embodiments, the capacitance of the primary first modulation capacitor Ccma1 and the capacitance of the secondary first modulation capacitor Ccma2 may be the same, and the capacitance of the primary second modulation capacitor Ccmb1 and the capacitance of the secondary second modulation capacitor Ccmb2 may be the same.

[0112] The first-level third selection switch SW3a is controlled by the first-level third selection signal SW_EN3a, and may include one end connected to the other electrode of the first-level first modulation capacitor Ccma1 and the other end connected to ground. The second-level third selection switch SW3b is controlled by the second-level third selection signal SW_EN3b, and may include one end connected to the other electrode of the first-level second modulation capacitor Ccmb1 and the other end connected to ground. The first-level fourth selection switch SW4a is controlled by the first-level fourth selection signal SW_EN4a, and may include one end connected to the other electrode of the second-level first modulation capacitor Ccma2 and the other end connected to ground. The second-level fourth selection switch SW4b is controlled by the second-level fourth selection signal SW_EN4b, and may include one end connected to the other electrode of the second-level second modulation capacitor Ccmb2 and the other end connected to ground.

[0113] Multiple selection signals SW_EN3a, SW_EN4a, SW_EN3b, and SW_EN4b can correspond to receiver data RD and... Figure 2 The controller 241 generates a second impedance control signal Ictrl2. Multiple selection switches SW3a, SW4a, SW3b, and SW4b can be closed based on multiple selection signals SW_EN3a, SW_EN4a, SW_EN3b, and SW_EN4b.

[0114] By controlling the closing operations of multiple selector switches SW3a, SW4a, SW3b, and SW4b, the electrical connections between the third node n3 and the fourth node n4 and the multiple modulation capacitors Ccma1, Ccma2, Ccmb1, and Ccmb2 can be controlled. The third node n3 and the fourth node n4 can be the nodes to which the output terminals of the receiver LC circuit LC2 are connected, and the modulation level can be adjusted when the electrical connections with the multiple modulation capacitors Ccma1, Ccma2, Ccmb1, and Ccmb2 are controlled.

[0115] According to some embodiments, Figure 2 The controller 241 can control the electrical connections between the third node n3 and the fourth node n4 and the plurality of modulation capacitors Ccma1, Ccma2, Ccmb1, and Ccmb2 based on the receiver data RD. According to some embodiments, Figure 2 The controller 241 can control the electrical connection between the third node n3 and the fourth node n4 and the multiple modulation capacitors Ccma1, Ccma2, Ccmb1, and Ccmb2 based on the second impedance control signal Ictrl2.

[0116] When the third node n3 and the fourth node n4 are connected to multiple modulation capacitors Ccma1, Ccma2, Ccmb1, and Ccmb2, the reactance of the load impedance fluctuates, and the voltage amplitude across the transmitter coil Lp, the voltage amplitude across the receiver coil Ls, and the magnitude of the rectified voltage Vrect can fluctuate.

[0117] Figure 5 This is a diagram illustrating the modeling of a wireless charging system in the frequency domain based on some example embodiments. Figure 6 and Figure 7 This is a diagram used to explain the received power signals according to some example embodiments.

[0118] Specifically, Figure 5 This is seen from the third node n3 and the fourth node n4 connected to the output terminals of the receiver LC circuit LC2. Figure 1 and Figure 4 The equivalent circuits of the first electronic device 10 and the second electronic device 20. Specifically, Figure 6 and Figure 7These are graphs showing the AC voltage signal V43 in the frequency domain and time domain, respectively. The AC voltage signal V43 is the power signal received at the third node n3 and the fourth node n4.

[0119] Reference Figure 1 , Figure 4 and Figure 5 When viewed from the third node n3 and the fourth node n4, the second electronic device 20 other than the receiver LC circuit LC2 can be modeled as the load circuit LDC in the frequency domain.

[0120] The load circuit LDC may include a modulation impedance Zcm, a modulation selection switch SWcm, and a power path impedance Zpp. Between the third node n3 and the fourth node n4, the modulation impedance Zcm and the modulation selection switch SWcm may be connected in parallel with the power path impedance Zpp.

[0121] The load circuit LDC can have an equivalent impedance value of load impedance Zload. The load impedance Zload can be calculated based on the modulation impedance Zcm and the power path impedance Zpp, depending on the operation of the modulation selection switch SWcm. In response to the modulation selection switch SWcm being open, the load impedance Zload can be equal to the power path impedance Zpp. In response to the modulation selection switch SWcm being short-circuited, the load impedance Zload can be calculated in parallel with the modulation impedance Zcm and the power path impedance Zpp.

[0122] The modulation impedance Zcm and the modulation selection switch SWcm can correspond to Figure 2 and Figure 4 The modulation circuit 245, and the modulation selection switch SWcm can correspond to Figure 4 Multiple selection switches SW3a, SW4a, SW3b, and SW4b. The modulation impedance Zcm can correspond to... Figure 4 The modulation circuit 245 has multiple modulation capacitors Ccma1, Ccma2, Ccmb1, and Ccmb2, and can represent the equivalent impedance values ​​of the multiple modulation capacitors Ccma1, Ccma2, Ccmb1, and Ccmb2 selected by multiple selection switches SW3a, SW4a, SW3b, and SW4b. The modulation impedance Zcm can be determined by the modulation capacitors of the modulation circuit 245.

[0123] According to some embodiments, the reactance component of the load impedance Zload can fluctuate in response to the connection between the third node n3 and the fourth node n4 and the plurality of modulation capacitors Ccma1, Ccma2, Ccmb1, Ccmb2.

[0124] The power path impedance Zpp represents the equivalent impedance of the portion of the second electronic device 20 excluding the receiver LC circuit LC2 and the modulation circuit 245. (Refer to...) Figure 4 As an example, the power path impedance Zpp can correspond to the total equivalent impedance value of the rectifier circuit 242, the resistive impedance control circuit 243, the regulator circuit 244, the charger 26, etc.

[0125] According to some embodiments, the AC voltage signal V43 can be applied between the third node n3 and the fourth node n4.

[0126] Through the switching operation of inverter circuit 13 and the narrowband filtering operation at the resonant frequency of receiver LC circuit LC2, AC voltage signal V43 may include impulse voltage signal (e.g., spike signal) at the resonant frequency and impulse voltage signal at the harmonic frequency of the resonant frequency. For example, AC voltage signal V43 may include impulse voltage (e.g., voltage spike) at the resonant frequency and pulse at the harmonic frequency of the resonant frequency.

[0127] See also Figure 6 and Figure 7 The AC voltage signal V43 can include the impulse voltage signal at the resonant frequency fo and the impulse voltage signal at the (2n+1)th harmonic of the resonant frequency fo. n is a natural number. The magnitude of the impulse voltage signal at the resonant frequency fo can be 4 / π times the rectified voltage Vrect and is determined by the load impedance Zload. Furthermore, the magnitude of the impulse voltage signal at the (2n+1)th harmonic of the resonant frequency fo can be determined by the load impedance Zload.

[0128] Therefore, the AC voltage signal V43 can be a square wave in the time domain with a resonant period T and an amplitude of rectified voltage Vrect. The resonant period T can be the reciprocal of the resonant frequency fo. Although the AC voltage signal V43 in... Figure 7 The signal is shown as a smooth square wave in the time domain, but is not limited thereto, and the AC voltage signal V43 may rise or fall with a non-zero slope value in some intervals.

[0129] When viewed from the third node n3 and the fourth node n4, the receiver LC circuit LC2 and the first electronic device 10 can be modeled as the total input LC circuit LC2rx in the frequency domain.

[0130] The total input LC circuit LC2rx may include a reflected power supply Vp_refl, a reflected impedance Zp_refl, and a receiving impedance Zs. Between the third node n3 and the fourth node n4, the reflected power supply Vp_refl, the reflected impedance Zp_refl, and the receiving impedance Zs can be connected in series.

[0131] The total input LC circuit LC2rx can have an equivalent impedance value of the total input impedance Zrx. The total input impedance Zrx can be calculated by series synthesis of the reflected impedance Zp_refl and the receiving impedance Zs.

[0132] The reflected power source Vp_refl can be represented as the reflected voltage induced when the magnetic field generated by the AC signal flowing in the transmitter coil Lp reaches the receiver coil Ls in the form of a "voltage source", and can be expressed as Equation 1 below.

[0133] (Equation 1)

[0134] In Equation 1, Vp_refl is the reflected voltage provided by the reflected power source as seen from the power receiver device. It is the angular frequency of the AC signal generated in the power transmitter device. It is the mutual inductance between the transmitter coil and the receiver coil. It is an AC signal generated in a power transmitter device, and It is the transmitting impedance of the transmitter LC circuit in the power transmitter device.

[0135] The reflected impedance Zp_refl can be expressed as "impedance" in the form of the electrical effect of the transmitter LC circuit LC1 on the receiver LC circuit LC2 during the mutual inductance process between the transmitter LC circuit LC1 and the receiver LC circuit LC2, and is expressed as Equation 2 below.

[0136] (Equation 2)

[0137] In equation 2, This is the reflected impedance as viewed from the power receiver device. It is the angular frequency of the reflected voltage. It is the mutual inductance between the transmitter coil and the receiver coil. It is the transmitting impedance of the transmitter LC circuit in the power transmitter device. It is the coupling coefficient between the transmitter coil in the power transmitter device and the receiver coil in the power receiver device. It is the inductance of the transmitter coil in the power transmitter device, and It is the inductance of the receiver coil in the power receiver device.

[0138] Based on Equation 2, the coupling coefficient k between the transmitter coil Lp and the receiver coil Ls can be expressed as shown in Equation 3 below.

[0139] (Equation 3)

[0140] Assuming that the magnitudes of the transmitting impedance Zp and the transmitter coil Lp are similar in Equation 3, the coupling coefficient k can be approximated as shown in Equation 4 below.

[0141] (Equation 4)

[0142] The coupling coefficient k can be calculated based on Equation 4 using the reflected impedance Zp_refl as observed from the second electronic device 20, which acts as a power receiver. According to some embodiments, the coupling coefficient k can be determined by the resistance and reactance of the reflected impedance Zp_refl.

[0143] The second electronic device 20 can obtain multiple equations for the unknown reflection impedance Zp_refl and reflection power supply Vp_refl while changing the load impedance Zload, and can calculate the estimated coupling coefficient value k_est by finding the solutions to the multiple equations.

[0144] Figure 8 This is a flowchart illustrating a method of operating an electronic device according to some example embodiments. Figures 9 to 11 This is a diagram used to explain a method of operating an electronic device according to some example embodiments.

[0145] Reference Figure 1 , Figure 2 , Figure 5 , Figure 6 and Figure 8 The second electronic device 20 detects the first electronic device 10 as a power transmitter device during the ping phase (S110).

[0146] The second electronic device 20, serving as a power receiver, can be arranged adjacent to the first electronic device 10. (Refer to...) Figure 9 As an example, the second electronic device 20 may be mounted on the outer surface of the first electronic device 10, and the receiver coil Ls of the second electronic device 20 and the transmitter coil Lp of the first electronic device 10 may be misaligned with each other in the first direction D1.

[0147] The first electronic device 10 can check whether the adjacent second electronic device 20 is included within the operating space during the ping phase. For example, during the ping phase, the first electronic device 10 can determine whether the second electronic device 20, located adjacent to the first electronic device 10, is located within a defined operating area. According to some embodiments, the first electronic device 10 can use simulated ping, apply NFC tag protection, or check for the presence of FOD (Foreign Object Detection).

[0148] If the first electronic device 10 confirms that the second electronic device 20 is included in the operating space, the first electronic device 10 may provide a digital ping to request signal strength packets during the ping phase.

[0149] The second electronic device 20 can provide signal strength data packets to the first electronic device 10 in response to the digital ping of the first electronic device 10 during the ping phase, and can detect the first electronic device 10.

[0150] The ping phase in step S110 can correspond to the ping phase defined in the WPC Qi standard.

[0151] The second electronic device 20 performs a rectification operation on the second power signal PS2 to generate a rectified voltage Vrect and a rectified current Irect (S120).

[0152] Following the ping phase in step S110, through a configuration phase and a negotiation phase, the second electronic device 20 can receive a second power signal PS2 based on a first power signal PS1 generated by the first electronic device 10. The second power signal PS2 can correspond to the first power signal PS1, and the magnitude of the second power signal PS2 can be determined by the magnitude of the first power signal PS1. Therefore, the magnitude of the second power signal PS2 can be based on the input voltage VIN.

[0153] Reference Figure 4 As an example, rectifier circuit 242 can perform a rectification operation on the second power signal PS2 to generate a rectified current Irect flowing to the rectifier node nr and to generate a rectified voltage Vrect applied to the rectifier node nr.

[0154] Additional reference Figure 10 At time t0, the first electronic device 10 can generate a first power signal PS1 based on the a-th input voltage VINa, and the second electronic device 20 can receive a second power signal PS2 corresponding to the a-th input voltage VINa.

[0155] The rectifier circuit 242 can perform a rectification operation on the second power signal PS2 corresponding to the a-th input voltage VINa, and can generate a current flowing to the rectifier node (e.g., Figure 4 The first rectified current Irect1 of the rectifier node nr in the middle, and can be generated and applied to the rectifier node (e.g., Figure 4 The first rectified voltage Vrect1 of the rectifier node nr in the rectifier.

[0156] The second electronic device 20 sends a control error packet to the first electronic device 10 to maintain the reception conditions of the power signal received from the first electronic device 10 (S130).

[0157] Corresponding to the reception of the second power signal PS2, the controller 241 of the second electronic device 20 can generate a zero (e.g., initial) control error packet CEP0 requesting that the reception conditions of the second power signal PS2 be maintained. For example, the second electronic device 20 may request the first electronic device 10 to maintain the input voltage VIN at the existing voltage (the a-th input voltage VINa) via the zero control error packet CEP0 during the calculation of the estimated coupling coefficient value k_est. The zero control error packet CEP0 is one of the control error packets defined in the WPC Qi standard and may be receiver data RD generated by the controller 241.

[0158] The transmitter controller 16 in the first electronic device 10 can provide a voltage control signal Vctrl to the power supply 11 based on the zero control error packet CEP0, and can maintain the input voltage VIN at the existing voltage (the a-th input voltage VINa).

[0159] At time t1, modulation circuit 245 can perform modulation operation based on the zero control error packet CEP0, and second electronic device 20 can send the zero control error packet CEP0 to first electronic device 10 through modulation operation. During modulation operation, the rectified voltage Vrect generated from rectifier circuit 242 can fluctuate.

[0160] At time t2, after sending the zeroth control error packet CEP0, the rectifier circuit 242 can perform a rectification operation on the second power signal PS2 and generate a first rectified current Irect1 and a first rectified voltage Vrect1. Furthermore, the load impedance measurement unit 246 can measure the first load impedance Zload1 corresponding to the first rectified current Irect1 based on the first rectified current Irect1 and the first rectified voltage Vrect1.

[0161] The second electronic device 20 changes the rectified current Irect to measure multiple load impedances Zload (S140) at the output terminal of the receiver LC circuit LC2.

[0162] The rectified current Irect can fluctuate based on the fluctuations of the resistive impedance regulation current Ira and the operating current Io. According to some embodiments, the resistive impedance control circuit 243 can change the rectified current Irect by changing the resistive impedance regulation current Ira based on a first impedance control signal Ictrl1. According to some embodiments, the controller 241 can change the rectified current Irect by changing the operating current Io (e.g., controlling the magnitude of the operating current Io) based on a regulator control signal DCctrl. As the rectified current Irect fluctuates due to the resistive impedance control circuit 243 and the controller 241, the load impedance Zload at the output terminal of the receiver LC circuit LC2 can fluctuate.

[0163] The load impedance measurement unit 246 can receive multiple rectified currents Irect and multiple rectified voltages Vrect corresponding to the multiple rectified currents Irect, and measure multiple load impedances Zload corresponding to the multiple rectified currents Irect based on the multiple rectified currents Irect and the multiple rectified voltages Vrect.

[0164] At time t3, the rectified current Irect can fluctuate from the first rectified current Irect1 to the second rectified current Irect2, and the rectifier circuit 242 can perform rectification operation and generate a second rectified voltage Vrect2 corresponding to the second rectified current Irect2. Furthermore, the load impedance measurement unit 246 can measure the second load impedance Zload2 corresponding to the second rectified current Irect2 based on the second rectified current Irect2 and the second rectified voltage Vrect2.

[0165] At time t4, the rectified current Irect can fluctuate from the second rectified current Irect2 to the third rectified current Irect3, and the rectifier circuit 242 can perform rectification operation and generate a third rectified voltage Vrect3 corresponding to the third rectified current Irect3. Furthermore, the load impedance measurement unit 246 can measure the third load impedance Zload3 corresponding to the third rectified current Irect3 based on the third rectified current Irect3 and the third rectified voltage Vrect3.

[0166] The first rectified voltage Vrect1 to the third rectified voltage Vrect3 measured from time t2 to time t4, and the first load impedance Zload1 to the third load impedance Zload3 corresponding to the first rectified voltage Vrect1 to the third rectified voltage Vrect3 respectively, can be provided to the coupling coefficient estimator unit 247.

[0167] The second electronic device 20 controls the connection of the capacitor at the output terminal of the receiver LC circuit LC2 to generate reactance information (S150).

[0168] The modulation circuit 245 can control the connection between the third node n3 and the fourth node n4 and the modulation capacitor based on the second impedance control signal Ictrl2, and the magnitude of the rectified voltage Vrect can fluctuate in response to the control of the connection between the third node n3 and the fourth node n4 and the modulation capacitor.

[0169] The load impedance measurement unit 246 can confirm the polarity of the total input reactance in the total input impedance Zrx, which is reactance information, based on the rectified voltage Vrect that fluctuates in response to the connection control of the modulation capacitor.

[0170] If the polarity of the total input reactance in the total input impedance Zrx is positive, the magnitude of the rectified voltage Vrect increases as the capacitance of the modulation circuit 245 connected to the third node n3 and the fourth node n4 increases. If the polarity of the reactance of the total input impedance Zrx is negative, the magnitude of the rectified voltage Vrect decreases as the capacitance of the modulation circuit 245 connected to the third node n3 and the fourth node n4 increases. The fluctuation trend of the rectified voltage Vrect according to the reactance polarity of the total input impedance Zrx will be described in the following description of step S160.

[0171] At time t5, the rectified current Irect can fluctuate from the third rectified current Irect3 to the first rectified current Irect1, and the modulation capacitor Ccm of the modulation circuit 245 connected to the third node n3 and the fourth node n4 can fluctuate from the first modulation capacitor Ccm1 to the second modulation capacitor Ccm2. In response to the rectified current Irect being the first rectified current Irect1 and the modulation capacitor Ccm being the second modulation capacitor Ccm2, the rectifier circuit 242 can generate a first modulated rectified voltage Vrect1_cm corresponding to the first rectified current Irect1 and the second modulation capacitor Ccm2.

[0172] At time t6, the modulation capacitor Ccm of the modulation circuit 245 connected to the third node n3 and the fourth node n4 can fluctuate from the second modulation capacitor Ccm2 to the first modulation capacitor Ccm1. In response to the rectified current Irect being the first rectified current Irect1 and the modulation capacitor Ccm being the first modulation capacitor Ccm1, the rectifier circuit 242 can generate a first rectified voltage Vrect1 corresponding to the first rectified current Irect1 and the first modulation capacitor Ccm1.

[0173] The load impedance measurement unit 246 can confirm the polarity of the total input impedance in the total input impedance Zrx, which is the reactance information, by comparing the magnitudes of the first modulated rectified voltage Vrect1_cm and the first rectified voltage Vrect1.

[0174] The second electronic device 20 calculates the coupling coefficient k (S160) based on multiple load impedances Zload and reactance information corresponding to multiple rectified currents Irect.

[0175] Assuming the modulation selection switch SWcm is open, the AC voltage signal V43 applied to the load impedance Zload can be based on Figure 5 and Figure 6 As shown in Equation 5 below.

[0176] (Equation 5)

[0177] In equation 5, It is the AC voltage signal applied to the load impedance. It refers to the magnitude of the rectified voltage output from the rectifier circuit in the power receiver device. It is the resonant angular frequency of the LC circuits of the transmitter and receiver. It is the reflected voltage provided by the reflected power source, as viewed from the power receiver device. This is the load impedance of the power receiver device as viewed from the power receiver device itself. This is the reflected impedance as viewed from the power receiver device, and It is the receiving impedance of the receiver LC circuit in the power receiver device.

[0178] By substituting the corresponding first rectified voltages Vrect1 to the third rectified voltages Vrect3 and the first load impedances Zload1 to the third load impedances Zload3 into the rectified voltages and load impedances in Equation 5, they can be expressed as Equations 6 to 8 below.

[0179] (Equation 6)

[0180] (Equation 7)

[0181] (Equation 8)

[0182] By dividing Equation 6 by Equation 7, we obtain the current ratio. The relationship between the first rectified current Irect1 and the second rectified current Irect2 can be obtained from Equation 9 below.

[0183] (Equation 9)

[0184] By dividing Equation 6 by Equation 8, we obtain the current ratio. The relationship between the first rectified current Irect1 and the third rectified current Irect3 can be obtained as shown in Equation 10 below.

[0185] (Equation 10)

[0186] Since the sum of the reflection impedance Zp_refl and the receiving impedance Zs is the total input impedance Zrx, each of Equations 9 and 10 can be simplified to Equations 11 and 12 below.

[0187] (Equation 11)

[0188] (Equation 12)

[0189] The total input impedance Zrx can be expressed as the total input resistance and the total input reactance, as shown in Equation 13 below.

[0190] (Equation 13)

[0191] In equation 13, It is the total input impedance. Xrx is the total input resistance, which is the resistive component of the total input impedance, and Xrx is the total input reactance, which is the reactive component of the total input impedance.

[0192] By performing a squaring operation on each of Equations 11 to 13, and then performing a polynomial operation on the total input resistance and total input reactance, the total input resistance and total input reactance can be expressed as Equation 14 below.

[0193] (Equation 14)

[0194]

[0195] In equation 14, Zrx is the total input resistance, which is the resistive component of the total input impedance Zrx, and Xrx is the total input reactance, which is the reactive component of the total input impedance Zrx. It is the ratio of the first rectified current Irect1 to the second rectified current Irect2. It is the ratio of the first rectified current Irect1 to the third rectified current Irect3. It is the first load impedance Zload1. It is the second load impedance Zload2. It is the third load impedance Zload3.

[0196] Since the reflection impedance Zp_refl can be expressed as the difference between the total input impedance Zrx and the receiving impedance Zs, the reflection resistance, which is the resistive component of the reflection impedance Zp_refl, and the reflection reactance, which is the reactive component of the reflection impedance Zp_refl, can be expressed as Equation 15 below.

[0197] (Equation 15)

[0198]

[0199] In equation 15, It is the reflected resistance, which is the resistive component of the reflected impedance Zp_refl. It is the receiving resistor, which serves as the resistive component of the LC circuit LC2 in the receiver. It is the reflected reactance, which is the reactance component of the reflected impedance Zp_refl, and It is the receiver reactance, which is the reactance component of the receiver LC circuit LC2.

[0200] The total input resistance, which is the resistive component of the total input impedance Zrx, is always positive because it is based on the transmitter coil Lp and the receiver coil Ls. However, the total input reactance, which is the reactance of the total input impedance Zrx, can be negative in the low-frequency band. Therefore, the polarity of the total input reactance must be confirmed.

[0201] Assuming the modulation selection switch SWcm is short-circuited, the AC voltage signal V43 applied to the load impedance Zload can be based on Figure 5 and Figure 6 It is represented by the following equation 16.

[0202] (Equation 16)

[0203] In equation 16, It is the AC voltage signal applied to the load impedance. It refers to the magnitude of the rectified voltage output from the rectifier circuit in the power receiver device. It is the resonant angular frequency of the LC circuits of the transmitter and receiver. It is the reflected voltage provided by the reflected power source, as viewed from the power receiver device. This is the load impedance of the power receiver device as viewed from the power receiver device itself. This is the total input impedance as viewed from the power receiver device, and It is the modulation impedance of the modulation circuit of the power receiver device.

[0204] The modulation impedance Zcm can be geometrically expressed as follows: (This is achieved using a capacitor via modulation circuit 245) And the total input impedance Zrx is geometrically expressed as Equation 16 can be expressed as Equation 17 below.

[0205] (Equation 17) .

[0206] In equation 17, It is the phase of the total input impedance Zrx, and the polarity is the reactance information of the total input impedance Zrx.

[0207] If the above If the value is 0 or greater, the polarity of the total input reactance of the total input impedance Zrx can be positive. If the size of the modulation capacitor used in the modulation circuit 245 increases, the size of the modulation impedance Zcm decreases. Therefore, if the polarity of the total input reactance is positive and the size of the modulation capacitor increases, the denominator component on the right side of Equation 17 can decrease and the size of the rectified voltage Vrect can increase.

[0208] Conversely, if the above If the value is less than 0, the polarity of the total input reactance Zrx can be negative. If the size of the modulation capacitor used in the modulation circuit 245 increases, the size of the modulation impedance Zcm decreases. Therefore, if the polarity of the total input reactance is negative and the size of the modulation capacitor increases, the denominator component on the right side of Equation 17 can increase and the size of the rectified voltage Vrect can decrease.

[0209] Therefore, the load impedance measurement unit 246 can determine the polarity of the total input reactance in the total input impedance Zrx by comparing the magnitudes of the first modulated rectified voltage Vrect1_cm and the first rectified voltage Vrect1. In response to the first modulated rectified voltage Vrect1_cm being greater than the first rectified voltage Vrect1, the load impedance measurement unit 246 can determine that the polarity of the total input reactance in the total input impedance Zrx is positive. In response to the first modulated rectified voltage Vrect1_cm being less than the first rectified voltage Vrect1, the load impedance measurement unit 246 can determine that the polarity of the total input reactance in the total input impedance Zrx is negative.

[0210] The coupling coefficient estimator unit 247 can calculate the reflection impedance Zp_refl by applying the reactance information, which confirms the polarity of the total input reactance in the total input impedance Zrx, to Equation 15, from the first rectified current Irect1 to the third rectified current Irect3, the first load impedance Zload1 to the third load impedance Zload3 corresponding to the first rectified current Irect1 to the third rectified current Irect3 respectively, and the total input reactance.

[0211] The coupling coefficient estimator unit 247 can calculate the estimated coupling coefficient value k_est by applying the calculated reflection impedance Zp_refl to Equation 4.

[0212] Reference Figure 10As an example, the rectified voltage Vrect fluctuates along with the rectified current Irect and the modulation capacitor Ccm. However, even under the same conditions, the value of the rectified voltage Vrect can differ depending on the coupling coefficient k between the coil of the first electronic device 10 and the receiver coil Ls of the second electronic device 20. The second rectified voltage Vrect2 between time t3 and time t4 when the coupling coefficient k is 0.9 can differ from the second rectified voltage Vrect2 between time t3 and time t4 when the coupling coefficient k is 0.7. Furthermore, the third rectified voltage Vrect3 between time t4 and time t5 when the coupling coefficient k is 0.9 can differ from the third rectified voltage Vrect3 between time t4 and time t5 when the coupling coefficient k is 0.7. Additionally, the first modulated rectified voltage Vrect1_cm between time t5 and time t6 when the coupling coefficient k is 0.9 can differ from the first modulated rectified voltage Vrect1_cm between time t5 and time t6 when the coupling coefficient k is 0.7.

[0213] The coupling coefficient estimator unit 247 can calculate the estimated coupling coefficient value k_est by measuring multiple load impedances Zload1 to Zload3 and reactance information while changing the rectified current Irect and the modulation capacitor Ccm.

[0214] According to some embodiments, the second electronic device 20 can change the resistive and reactive components of the load impedance Zload through the resistive impedance control circuit 243 and the modulation circuit 245, measure the rectified voltage Vrect that fluctuates in response thereto, and calculate the estimated coupling coefficient value k_est between the coil of the first electronic device 10 and the receiver coil Ls of the second electronic device 20 based on the measured rectified voltage Vrect.

[0215] The controller 241 compares the estimated coupling coefficient value k_est with the predetermined threshold TH (S170).

[0216] The controller 241 may receive the estimated coupling coefficient value k_est calculated by the coupling coefficient estimator unit 247.

[0217] The controller 241 compares the estimated coupling coefficient value k_est with a predetermined threshold TH, and based on the comparison result, provides alignment feedback data FBD for the alignment between the transmitter coil of the first electronic device 10 and the receiver coil of the second electronic device 20 to the processor 21. The estimated coupling coefficient value k_est can be a predetermined real number less than or equal to 1. The predetermined threshold TH can be determined to be a value closer to 1. For example, the predetermined threshold TH can be 0.9. The predetermined threshold TH can be stored in memory 22.

[0218] In response to the estimated coupling coefficient value k_est being less than a predetermined threshold TH, the processor 21 sends negative feedback about alignment to the user interface 23 (S180).

[0219] In response to the estimated coupling coefficient value k_est being less than a predetermined threshold TH, the controller 241 may send negative alignment feedback data FBD to the processor 21. In response to the negative alignment feedback data FBD, the processor 21 may provide negative feedback regarding alignment to the user interface 23.

[0220] In response to receiving negative feedback about alignment from processor 21, user interface 23 may display "The receiver coil Ls and the coils of transmitter LC circuit LC1 are misaligned." For example, when user interface 23 is a display, processor 21 may use user interface 23 to display information informing the user of the misalignment between the receiver coil Ls and the coils of transmitter LC circuit LC1.

[0221] Reference Figure 11 As an example, in response to receiving negative feedback about alignment from processor 21, display 231 of user interface 23 may display "MISALIGN" indicating the meaning of "misalignment", and vibrator of user interface 23 may perform vibration operation to vibrate second electronic device 20.

[0222] Through the operation of the user interface 23 as described above, the second electronic device 20 can inform the user of the alignment status between the coils and can prompt the user to adjust the alignment status between the first electronic device 10 and the second electronic device 20.

[0223] In response to the estimated coupling coefficient value k_est being less than a predetermined threshold TH, the second electronic device 20 sends the estimated coupling coefficient value k_est to the first electronic device 10 (S190).

[0224] In response to the estimated coupling coefficient value k_est being less than a predetermined threshold TH, controller 241 can provide receiver data RD corresponding to the estimated coupling coefficient value k_est to modulation circuit 245, thereby performing a modulation operation for the estimated coupling coefficient value k_est. Modulation circuit 245 can perform the modulation operation in response to the receiver data RD corresponding to the estimated coupling coefficient value k_est. In response to the modulation operation, the modulation capacitance of modulation circuit 245 connected to the output terminal of receiver LC circuit LC2 fluctuates, and the difference in the amplitude of the voltage applied to transmitter LC circuit LC1 can be adjusted. Demodulation circuit 15 can demodulate the amplitude of the voltage applied to the coil of transmitter LC circuit LC1 to generate a demodulation signal Vdemod, and transmitter controller 16 can receive receiver data RD corresponding to the estimated coupling coefficient value k_est based on the demodulation signal Vdemod.

[0225] If the estimated coupling coefficient value k_est is less than a predetermined threshold TH, steps S180, S190, and steps S130 to S170 can be repeated.

[0226] Despite Figure 8 Step S180 is shown as preceding step S190, but is not limited thereto, and according to embodiments, step S190 may precede step S180, or steps S180 and S190 may be performed together.

[0227] In response to the estimated coupling coefficient value k_est being equal to or greater than a predetermined threshold TH, the processor 21 sends positive feedback about alignment to the user interface 23 (S200).

[0228] In response to an estimated coupling coefficient value k_est being equal to or greater than a predetermined threshold TH, controller 241 may send positive alignment feedback data FBD to processor 21. In response to the positive alignment feedback data FBD, processor 21 may send positive feedback regarding alignment to user interface 23.

[0229] In response to receiving positive feedback about alignment from processor 21, user interface 23 may display "The coils of receiver coil Ls and transmitter LC circuit LC1 are aligned with each other". For example, in response to receiving positive feedback about alignment from processor 21, display 231 of user interface 23 may display "ALIGN" indicating the meaning of "alignment".

[0230] The second electronic device 20, by executing steps S130 to S160, can measure multiple load impedances Zload corresponding to multiple rectified currents Irect by changing the rectified current Irect, and calculate an estimated coupling coefficient value k_est between the receiver coil Ls and the coil of the transmitter LC circuit LC1 using the multiple rectified currents Irect and the multiple load impedances Zload. The second electronic device 20 can then execute steps S110 to S200 to perform a display operation on the user interface 23 based on the estimated coupling coefficient value k_est, so that the user is aware of the alignment status between the coils. The second electronic device 20 can prompt the user to adjust the alignment status between the first electronic device 10 and the second electronic device 20 without the need for individual components (such as magnets for coil alignment).

[0231] Figure 12 This is a timing diagram used to explain a method of operating an electronic device according to some embodiments.

[0232] Reference Figure 1 , Figure 2 , Figure 5 and Figure 12At time t10, the first electronic device 10 can generate a first power signal PS1 based on the b-th input voltage VINb, and the second electronic device 20 can receive a second power signal PS2 corresponding to the b-th input voltage VINb. The rectifier circuit 242 can perform rectification on the second power signal PS2 corresponding to the b-th input voltage VINb, and generate a current flowing to the rectifier node (e.g., Figure 4 The first rectified current Irect1 of the rectifier node nr in the middle is generated and applied to the rectifier node (e.g., Figure 4 The first rectified voltage Vrect1 of the rectifier node nr in the rectifier.

[0233] At time t11, modulation circuit 245 can perform modulation operation based on the zero control error packet CEP0, and second electronic device 20 can send the zero control error packet CEP0 to first electronic device 10 through modulation operation. During modulation operation, the rectified voltage Vrect generated from rectifier circuit 242 can fluctuate.

[0234] The zeroth control error packet CEP0 is a control error packet requesting that the reception conditions of the second power signal PS2 be maintained. For example, the second electronic device 20 may request the first electronic device 10 to maintain the input voltage VIN at the existing voltage (b-th input voltage VINb) via the zeroth control error packet CEP0 during the calculation of the estimated coupling coefficient value k_est. The transmitter controller 16 in the first electronic device 10 may provide a voltage control signal Vctrl to the power supply 11 based on the zeroth control error packet CEP0 and maintain the input voltage VIN at the existing voltage (b-th input voltage VINb).

[0235] At time t12, after sending the zeroth control error packet CEP0, the rectifier circuit 242 can perform a rectification operation on the second power signal PS2 and generate a first rectified current Irect1 and a first rectified voltage Vrect1. Furthermore, the load impedance measurement unit 246 can measure the first load impedance Zload1 corresponding to the first rectified current Irect1 based on the first rectified current Irect1 and the first rectified voltage Vrect1.

[0236] At time t13, the rectified current Irect can fluctuate from the first rectified current Irect1 to the second rectified current Irect2, and the rectifier circuit 242 can perform rectification operation and generate a second rectified voltage Vrect2 corresponding to the second rectified current Irect2. Furthermore, the load impedance measurement unit 246 can measure the second load impedance Zload2 corresponding to the second rectified current Irect2 based on the second rectified current Irect2 and the second rectified voltage Vrect2.

[0237] At time t14, the rectified current Irect can fluctuate from the second rectified current Irect2 to the third rectified current Irect3, and the rectifier circuit 242 can perform rectification operation and generate a third rectified voltage Vrect3 corresponding to the third rectified current Irect3. Furthermore, the load impedance measurement unit 246 can measure the third load impedance Zload3 corresponding to the third rectified current Irect3 based on the third rectified current Irect3 and the third rectified voltage Vrect3.

[0238] The first rectified current Irect1 to the third rectified current Irect3 fluctuating from time t12 to time t14, the measured first rectified voltage Vrect1 to the third rectified voltage Vrect3, and the first load impedance Zload1 to the third load impedance Zload3 corresponding to the first rectified voltage Vrect1 to the third rectified voltage Vrect3 respectively can be provided to the coupling coefficient estimator unit 247.

[0239] At time t15, the rectified current Irect can fluctuate from the third rectified current Irect3 to the first rectified current Irect1. In response to the rectified current Irect being the first rectified current Irect1, the rectifier circuit 242 can generate a first rectified voltage Vrect1 corresponding to the first rectified current Irect1.

[0240] Assuming that the reactance polarity of the total input impedance Zrx is positive, taking into account the frequency of the power signal as defined in the Qi standard of WPC, the coupling coefficient estimator unit 247 can calculate the reflected resistance as the resistive component of the reflected impedance Zp_refl and the reflected reactance as the reactance component of the reflected impedance Zp_refl, as shown in Equation 18 below.

[0241] (Equation 18)

[0242]

[0243]

[0244] In equation 18, It is the total input resistance, which is the resistive component of the total input impedance Zrx. It is the reflected resistance, which is the resistive component of the reflected impedance Zp_refl. It is the reflected reactance, which is the reactance component of the reflected impedance Zp_refl. It is the ratio of the first rectified current Irect1 to the second rectified current Irect2. It is the ratio of the first rectified current Irect1 to the third rectified current Irect3. It is the first load impedance Zload1. It is the second load impedance Zload2. It is the third load impedance Zload3. It is the receiving resistor, which serves as the resistive component of the LC circuit LC2 in the receiver. It is the receiver reactance, which is the reactance component of the receiver LC circuit LC2.

[0245] The coupling coefficient estimator unit 247 can calculate the estimated coupling coefficient value k_est by applying the calculated reflection impedance Zp_refl to Equation 4.

[0246] Reference Figure 12 As an example, the rectified voltage Vrect may fluctuate along with the rectified current Irect, but even under the same conditions, this value may differ depending on the coupling coefficient k between the coil of the first electronic device 10 and the receiver coil Ls of the second electronic device 20. The second rectified voltage Vrect2 between time t13 and time t14 when the coupling coefficient k is 0.9 may differ from the second rectified voltage Vrect2 between time t13 and time t14 when the coupling coefficient k is 0.7. Furthermore, the third rectified voltage Vrect3 between time t14 and time t15 when the coupling coefficient k is 0.9 may differ from the third rectified voltage Vrect3 between time t14 and time t15 when the coupling coefficient k is 0.7.

[0247] The second electronic device 20 can easily estimate the coupling coefficient between the receiver coil Ls and the coil of the transmitter LC circuit LC1, depending on the circumstances (such as the frequency of the power signal as defined in the WPC Qi standard).

[0248] Furthermore, the second electronic device 20 can perform the display operation of the user interface 23 based on the calculated estimated coupling coefficient value k_est, so that the user is aware of the alignment status between the coils. The second electronic device 20 can prompt the user to adjust the alignment status between the first electronic device 10 and the second electronic device 20 without the need for individual components (such as magnets for coil alignment).

[0249] Figure 13 This is a timing diagram used to explain a method of operating an electronic device according to some example embodiments.

[0250] Reference Figure 1 , Figure 2 , Figure 5 and Figure 13At time t20, the first electronic device 10 can generate a first power signal PS1 based on the c-th input voltage VINc, and the second electronic device 20 can receive a second power signal PS2 corresponding to the c-th input voltage VINc. The rectifier circuit 242 can perform rectification on the second power signal PS2 corresponding to the c-th input voltage VINc and generate a current flowing to the rectifier node (e.g., ...). Figure 4 The first rectified current Irect1 of the rectifier node nr is generated and applied to the rectifier node ( Figure 4 The first rectified voltage Vrect1 of the rectifier node nr in the rectifier.

[0251] At time t21, modulation circuit 245 can perform modulation operation based on the zero control error packet CEP0, and second electronic device 20 can send the zero control error packet CEP0 to first electronic device 10 through modulation operation. During modulation operation, the rectified voltage Vrect generated from rectifier circuit 242 can fluctuate.

[0252] The zeroth control error packet CEP0 is a control error packet requesting that the reception conditions of the second power signal PS2 be maintained. For example, the second electronic device 20 may request the first electronic device 10 to maintain the input voltage VIN at the existing voltage (cth input voltage VINc) via the zeroth control error packet CEP0 during the calculation of the estimated coupling coefficient value k_est. The transmitter controller 16 in the first electronic device 10 may provide a voltage control signal Vctrl to the power supply 11 based on the zeroth control error packet CEP0, and may maintain the input voltage VIN at the existing voltage (cth input voltage VINc).

[0253] At time t22, after sending the zeroth control error packet CEP0, the rectifier circuit 242 can perform a rectification operation on the second power signal PS2 and can generate a first rectified current Irect1 and a first rectified voltage Vrect1. Furthermore, the load impedance measurement unit 246 can measure the first load impedance Zload1 corresponding to the first rectified current Irect1 based on the first rectified current Irect1 and the first rectified voltage Vrect1.

[0254] At time t23, the rectified current Irect can fluctuate from the first rectified current Irect1 to the second rectified current Irect2, and the rectifier circuit 242 can perform rectification operation and generate a second rectified voltage Vrect2 corresponding to the second rectified current Irect2. Furthermore, the load impedance measurement unit 246 can measure the second load impedance Zload2 corresponding to the second rectified current Irect2 based on the second rectified current Irect2 and the second rectified voltage Vrect2.

[0255] The first rectified current Irect1 to the second rectified current Irect2, the measured first rectified voltage Vrect1 and second rectified voltage Vrect2, and the first load impedance Zload1 and the second load impedance Zload2 corresponding to the first rectified voltage Vrect1 and the second rectified voltage Vrect2 fluctuating at time t22 and time t23, respectively, can be provided to the coupling coefficient estimator unit 247.

[0256] At time t24, the rectified current Irect can fluctuate from the second rectified current Irect2 to the first rectified current Irect1. In response to the rectified current Irect being the first rectified current Irect1, the rectifier circuit 242 can generate a first rectified voltage Vrect1 corresponding to the first rectified current Irect1.

[0257] If the frequency of the power signal is greater than a predetermined value (e.g., if the frequency of the power signal is greater than 300 kHz), the reactive component of the total input impedance Zrx is significantly greater than the resistive component of the total input impedance Zrx, therefore the resistive component of the total input impedance Zrx can be ignored in circuit analysis. The coupling coefficient estimator unit 247 can calculate the reflection impedance Zp_refl as shown in Equation 19 below.

[0258] (Equation 19)

[0259] In equation 19, It is the reflection impedance Zp_refl. It is the ratio of the first rectified current Irect1 to the second rectified current Irect2. It is the first load impedance Zload1. It is the second load impedance Zload2. It is the receiver reactance, which is the reactance component of the receiver LC circuit LC2.

[0260] The coupling coefficient estimator unit 247 can calculate the estimated coupling coefficient value k_est by applying the calculated reflection impedance Zp_refl to Equation 4.

[0261] Reference Figure 13 As an example, the rectified voltage Vrect may fluctuate along with the rectified current Irect, but even under the same conditions, the value of the rectified voltage Vrect may differ depending on the coupling coefficient k between the coil of the first electronic device 10 and the receiver coil Ls of the second electronic device 20. The second rectified voltage Vrect2 between time t23 and time t24 when the coupling coefficient k is 0.9 may differ from the second rectified voltage Vrect2 between time t23 and time t24 when the coupling coefficient k is 0.7.

[0262] The second electronic device 20 can easily estimate the coupling coefficient between the receiver coil Ls and the coil of the transmitter LC circuit LC1, depending on the circumstances (such as when the frequency of the power signal is higher than a certain frequency).

[0263] Furthermore, the second electronic device 20 can perform the display operation of the user interface 23 based on the calculated estimated coupling coefficient value k_est, so that the user is aware of the alignment status between the coils. The second electronic device 20 can prompt the user to adjust the alignment status between the first electronic device 10 and the second electronic device 20 without the need for individual components (such as magnets for coil alignment).

[0264] Figure 14 This is a flowchart illustrating a method of operating an electronic device according to some example embodiments. Figures 15 to 16 This is a diagram used to explain a method of operating an electronic device according to some example embodiments.

[0265] Reference Figure 1 , Figure 2 and Figure 14 The first electronic device 10 detects the second electronic device 20, which is a power receiver device, during the ping phase (S310).

[0266] Additional reference Figure 15 The first electronic device 10, which serves as a power transmitter, may be arranged adjacent to the second electronic device 20. The second electronic device 20 may be mounted on the outer surface of the first electronic device 10, and the receiver coil Ls of the second electronic device 20 and the coil Lp of the first electronic device 10 may be misaligned with each other in the first direction D1.

[0267] The first electronic device 10 can check during the ping phase whether the adjacent second electronic device 20 is included within the operating space. According to some embodiments, the first electronic device 10 can use simulated ping, apply NFC tag protection, or check the presence of FOD.

[0268] If the first electronic device 10 confirms that the second electronic device 20 is included in the operating space, the first electronic device 10 may provide a digital ping to request signal strength packets during the ping phase.

[0269] The second electronic device 20 may provide a signal strength data packet to the first electronic device 10 in response to the digital ping of the first electronic device 10 during the ping phase, and detect the first electronic device 10.

[0270] The ping phase in step S310 can correspond to the ping phase defined in the WPC Qi standard, and can correspond to Figure 8The ping phase in step S110.

[0271] The first electronic device 10 receives the control error packet from the second electronic device 20 and maintains the transmission condition of the power signal sent to the second electronic device 20 (S320).

[0272] Following the ping phase in step S310, through a configuration phase and a negotiation phase, the first electronic device 10 can send a first power signal PS1 to the second electronic device 20. Through the transmission of the first power signal PS1, the second electronic device 20 can receive a second power signal PS2 corresponding to the first power signal PS1.

[0273] Corresponding to the reception of the second power signal PS2, the second electronic device 20 may generate a zero control error packet (CEP0) requesting the maintenance of the reception conditions for the second power signal PS2. The zero control error packet CEP0 may be one of the control error packets defined in the WPC's Qi standard, and the transmitter controller 16 may receive the zero control error packet CEP0 via the demodulation circuit 15. For example, the second electronic device 20 may request the first electronic device 10 to maintain the input voltage VIN or the frequency of the first power signal PS1 via the zero control error packet CEP0 during the estimation of the coupling coefficient. In response to receiving the zero control error packet CEP0, the first electronic device 10 may maintain the input voltage VIN and transmit the first power signal PS1 based on the maintained input voltage VIN, and may maintain the frequency of the first power signal PS1.

[0274] The step of receiving the control error packet CEP0 in step S320 can correspond to Figure 8 The step S130 involves sending a control error packet CEP0.

[0275] The first electronic device 10 receives the estimated coupling coefficient value k_est (S330) calculated by the second electronic device 20.

[0276] The second electronic device 20 can perform a modulation operation in response to receiver data RD corresponding to the estimated coupling coefficient value k_est. In response to the modulation operation, the modulation capacitor of the modulation circuit 245 connected to the output terminal of the receiver LC circuit LC2 can fluctuate, and the difference in the amplitude of the voltage applied to the transmitter LC circuit LC1 can be adjusted.

[0277] The demodulation circuit 15 can demodulate the amplitude of the voltage applied to the coil of the transmitter LC circuit LC1 to generate a demodulation signal Vdemod, and the transmitter controller 16 can receive and hold the estimated coupling coefficient value k_est corresponding to the transmission conditions based on the demodulation signal Vdemod.

[0278] The step of receiving the estimated coupling coefficient value k_est in step S330 can correspond to Figure 8 The step S190 is the step of sending the estimated coupling coefficient value k_est.

[0279] The transmitter controller 16 compares the estimated coupling coefficient value k_est with a predetermined threshold TH (S340).

[0280] The transmitter controller 16 can compare the estimated coupling coefficient value k_est with a predetermined threshold TH, and provide the position control signal Lctrl to the pad unit 14 based on the comparison result. The estimated coupling coefficient value k_est can be a predetermined real number less than or equal to 1.

[0281] In response to the estimated coupling coefficient value k_est being less than a predetermined threshold TH, the transmitter controller 16 checks whether the received estimated coupling coefficient value k_est is the initial value (S350).

[0282] In response to the estimated coupling coefficient value k_est being an initial value, the transmitter controller 16 moves the transmitter coil Lp in a predetermined direction (S360).

[0283] In response to the estimated coupling coefficient value k_est being an initial value, the transmitter controller 16 can provide the position control signal Lctrl to the pad unit 14, and the pad unit 14 can move the coil of the transmitter LC circuit LC1 in a predetermined direction.

[0284] In response that the estimated coupling coefficient value k_est is not the initial value, the transmitter controller 16 compares the previously estimated coupling coefficient value k_est' with the estimated coupling coefficient value k_est (S370).

[0285] If the estimated coupling coefficient value k_est is not the initial value, the transmitter controller 16 may receive the previously estimated coupling coefficient value k_est' based on the demodulation signal Vdemod before receiving the estimated coupling coefficient value k_est.

[0286] In response to the estimated coupling coefficient value k_est being greater than the previously estimated coupling coefficient value k_est', the transmitter controller 16 moves the transmitter coil Lp in the previously moved direction (S380).

[0287] In response to the estimated coupling coefficient value k_est being greater than the previously estimated coupling coefficient value k_est', the transmitter controller 16 may provide the position control signal Lctrl to the pad unit 14, and the pad unit 14 may move the coil of the transmitter LC circuit LC1 in the previously moved direction.

[0288] In response to the estimated coupling coefficient value k_est being less than or equal to the previously estimated coupling coefficient value k_est', the transmitter controller 16 moves the transmitter coil Lp in a direction different from the previous moving direction (S390).

[0289] In response to an estimated coupling coefficient value k_est being less than or equal to a previously estimated coupling coefficient value k_est', the transmitter controller 16 may provide a position control signal Lctrl to the pad unit 14, and the pad unit 14 may move the coil of the transmitter LC circuit LC1 in a direction different from the previous direction of movement.

[0290] If the estimated coupling coefficient value k_est is less than a predetermined threshold TH, steps S350 to S390 and steps S320 to S340 can be repeated.

[0291] By repeatedly executing steps S350 to S390 and steps S320 to S340, the coil of the transmitter LC circuit LC1 can move within the housing of the pad unit 14 in the direction that the coupling coefficient k with the receiver coil Ls increases. (Refer to...) Figure 15 and Figure 16 As an example, when the second electronic device 20 is mounted on the first electronic device 10, the transmitter coil Lp is initially misaligned with the receiver coil Ls in the first direction D1. However, by repeatedly executing steps S350 to S390 and steps S320 to S340, the transmitter coil Lp can be moved within the housing of the pad unit 14 in the first direction D1. This movement of the transmitter coil Lp aligns the transmitter coil Lp and the receiver coil Ls with each other, and increases the coupling coefficient k between them.

[0292] The first electronic device 10, acting as a power transmitter, can repeatedly receive an estimated coupling coefficient value k_est from the second electronic device 20, and based on this, move the coil in the direction that increases the coupling coefficient k between the coil of the first electronic device 10 and the coil of the second electronic device 20. Through the movement of the coil in the first electronic device 10, the second electronic device 20, acting as a power receiver in the wireless charging system 1, can cost-effectively achieve optimal alignment between the coils without the need for separate components (such as magnets for alignment).

[0293] Although embodiments of the present disclosure have been described in detail above, the scope of the present disclosure is not limited thereto. Various modifications and improvements made by those skilled in the art using the basic concept of the present disclosure as defined in the appended claims also fall within the scope of the present disclosure.

Claims

1. An electronic device comprising: An LC circuit includes a coil and a first capacitor, and is configured to receive an electrical signal through induction of the coil; The rectifier circuit is configured to generate DC voltage and DC current based on power signals; The regulator circuit is configured to perform a conversion operation based on DC voltage and DC current to generate an output voltage; An impedance control circuit is located between the rectifier circuit and the regulator circuit and is configured to perform the operation of changing the DC current. as well as The coupling coefficient estimator is configured to calculate an estimated coupling coefficient value between the coil and the external coil based on the DC current and the load impedance corresponding to the DC current.

2. The electronic device as claimed in claim 1, in, The rectifier circuit is configured to apply a DC voltage to the rectifier node and output a DC current to the rectifier node. The regulator circuit is connected to the rectifier node and configured to receive operating current from the rectifier node. The impedance control circuit is connected to the rectifier node and is configured to receive impedance-regulated current from the rectifier node.

3. The electronic device as claimed in claim 2, in, The impedance control circuit includes a variable current source, one end of which is connected to the rectifier node and the other end of which is grounded, and the variable current source is configured to control the impedance regulation current.

4. The electronic device as claimed in claim 2, in, The impedance control circuit includes a variable resistor, one end of which is connected to the rectifier node and the other end of which is grounded, and the resistance value of the variable resistor is configured to be adjustable.

5. The electronic device of claim 2, further comprising: The controller is configured to control the magnitude of the operating current.

6. The electronic device of claim 1, further comprising: The load impedance measurement unit is configured to measure the load impedance at the output terminal of the LC circuit based on DC voltage and DC current.

7. The electronic device as claimed in claim 6, in, The direct current includes a first direct current, a second direct current, and a third direct current, each having a different magnitude. The DC voltage includes the first DC voltage, the second DC voltage, and the third DC voltage output from the rectifier circuit, which correspond to the first DC current, the second DC current, and the third DC current, respectively. The load impedance includes a first load impedance measured based on a first DC current and a first DC voltage, a second load impedance measured based on a second DC current and a second DC voltage, and a third load impedance measured based on a third DC current and a third DC voltage. The estimated coupling coefficient values ​​are calculated based on the first DC current to the third DC current and the first load impedance to the third load impedance.

8. The electronic device of claim 7, further comprising: The modulation circuit is configured to control the connection between the output terminal of the LC circuit and the second capacitor. The load impedance measurement unit is configured to determine the reactance information of the total input impedance in the LC circuit based on the magnitude of the DC voltage fluctuating according to the connection between the output terminal of the LC circuit and the second capacitor. The coupling coefficient estimator is also configured to calculate the estimated coupling coefficient value based on reactance information, the first DC current to the third DC current, and the first load impedance to the third load impedance.

9. The electronic device as claimed in claim 6, in, Direct current includes a first direct current and a second direct current, which have different magnitudes from each other. The DC voltage includes a first DC voltage and a second DC voltage output from the rectifier circuit, which correspond to the first DC current and the second DC current, respectively. The load impedance includes a first load impedance measured based on a first DC current and a first DC voltage, and a second load impedance measured based on a second DC current and a second DC voltage. The estimated coupling coefficient value is calculated based on the first DC current, the second DC current, the first load impedance, and the second load impedance.

10. The electronic device according to any one of claims 1 to 9, further comprising: The user interface is configured to display information indicating misalignment between the coil and the external coil in response to an estimated coupling coefficient value being less than a predetermined threshold.

11. The electronic device as claimed in any one of claims 1 to 9, in, When the impedance control circuit performs an operation to change the DC current, the magnitude of the power signal is maintained.

12. A method of operating an electronic device, comprising: Detection of the proximity of external electronic devices based on the ping phase; The power signal received from the external electronic device is rectified to generate a DC current flowing to the rectifier node of the electronic device and a DC voltage applied to the rectifier node. The control error packet is sent to the external electronic device to maintain the reception condition of the power signal received by the LC circuit of the electronic device from the external electronic device. The DC current is varied to measure multiple load impedances at the output terminals of the LC circuit. The estimated coupling coefficient between the external coil in the external electronic device and the internal coil in the LC circuit is calculated based on the multiple load impedances. The estimated coupling coefficient value is compared with the threshold; as well as In response to an estimated coupling coefficient value being less than the threshold, negative feedback regarding the alignment between the outer and inner coils is sent to the user interface of the electronic device.

13. The method of operating an electronic device as described in claim 12, in, The step of changing the DC current to measure the impedance of the plurality of loads includes controlling the impedance regulation current flowing out of the rectifier node.

14. The method of operating an electronic device as described in claim 13, in, The direct current includes a first direct current, a second direct current, and a third direct current generated according to the control of the impedance-regulated current. The DC voltages include a first DC voltage, a second DC voltage, and a third DC voltage applied to the rectifier node and corresponding to the first DC current, the second DC current, and the third DC current, respectively. The plurality of load impedances includes a first load impedance measured based on a first DC current and a first DC voltage, a second load impedance measured based on a second DC current and a second DC voltage, and a third load impedance measured based on a third DC current and a third DC voltage. The estimated coupling coefficient values ​​are calculated based on the first DC current to the third DC current and the first load impedance to the third load impedance.

15. The method of operating an electronic device as claimed in any one of claims 12 to 14, further comprising: The connection between the output terminal of the LC circuit and the capacitor is controlled to generate reactance information of the total input impedance of the LC circuit. The estimated coupling coefficient value is calculated based on the multiple load impedance and reactance information.

16. The method of operating an electronic device as claimed in any one of claims 12 to 14, further comprising: In response to the estimated coupling coefficient value being less than a threshold, the estimated coupling coefficient value is sent to an external electronic device.

17. A wireless charging system, comprising: A first electronic device includes: a power supply configured to provide an input voltage; a first LC circuit including a first coil and a first capacitor and configured to transmit a first electrical signal corresponding to the input voltage through induction of the first coil; and a demodulation circuit configured to generate a demodulated signal including a data packet for the first electrical signal; and The second electronic device includes: a second LC circuit comprising a second coil and a second capacitor and configured to receive a second power signal corresponding to a first power signal via the mutual inductance of the first coil and the second coil; a rectifier circuit configured to generate a DC voltage and a DC current based on the second power signal; an impedance control circuit configured to perform an operation to change the DC current; a controller configured to generate a control error packet requesting to maintain the input voltage prior to the operation to change the DC current; and a modulation circuit configured to perform a modulation operation on the control error packet using the second power signal.

18. The wireless charging system as described in claim 17, in, The second electronic device also includes a coupling coefficient estimator configured to calculate an estimated coupling coefficient value between the first coil and the second coil based on the DC current and the load impedance corresponding to the DC current.

19. The wireless charging system as described in claim 18, in, The second electronic device further includes a load impedance measuring unit configured to measure the load impedance at the output terminal of the second LC circuit based on DC voltage and DC current. The direct current includes a first direct current, a second direct current, and a third direct current, each having a different magnitude. The load impedance is measured based on the operation of changing the DC current, and includes a first load impedance, a second load impedance, and a third load impedance corresponding to a first DC current, a second DC current, and a third DC current, respectively. When the input voltage is held, the coupling coefficient estimator is configured to receive the first load impedance to the third load impedance.

20. The wireless charging system as described in any one of claims 17 to 19, in, The modulation circuit is configured to control the connection between the output terminal of the second LC circuit and the modulation capacitor during modulation operation to regulate the magnitude of the DC voltage.

Images