KR102481948B1 - Wireless power transmitter - Google Patents

Abstract

The wireless power transmitter wirelessly charging the wireless power receiver adjusts the phase of the generated differential signal through a plurality of inverters based on a signal generator for generating a differential signal and a control signal for controlling phase adjustment of the differential signal. a modulator, an amplifier that amplifies the adjusted differential signal with a preset gain, a resonance unit that transmits the amplified differential signal to the wireless power receiver, a sensing unit that senses voltage and current of the amplified differential signal, and the Based on the sensed voltage and current, the control unit may include a control unit that generates the control signal for controlling a phase difference between signals included in the amplified differential signal to be a preset phase difference and outputs the generated control signal to the modulator.

Description

Wireless power transmitter {WIRELESS POWER TRANSMITTER}

The present invention relates to a wireless power transmitter, and relates to a wireless power transmitter that wirelessly transmits power to at least one wireless power receiver.

Mobile terminals such as mobile phones or PDAs (Personal Digital Assistants) are driven by rechargeable batteries due to their characteristics. Typically, the charging device and the battery are configured with separate contact terminals, respectively, to contact each other to electrically connect the charging device and the battery.

However, since the contact terminal protrudes from the outside of the contact charging method, it is easily contaminated by foreign substances, and for this reason, battery charging may not be performed correctly. Also, if the contact terminal is exposed to moisture, charging may not be performed correctly.

In order to solve this problem, wireless charging or non-contact charging technology has recently been developed and used in many electronic devices.

This wireless charging technology uses wireless power transmission and reception, and is a system in which, for example, a battery can be automatically charged by simply placing a mobile phone on a charging pad without connecting a separate charging connector. In general, it is known to the general public as a cordless electric toothbrush or a cordless electric shaver. This wireless charging technology can increase the waterproof function by wirelessly charging electronic products, and it does not require a wired charger, so it has the advantage of increasing the portability of electronic devices. .

These wireless charging technologies include an electromagnetic induction method using a coil, a resonance method using resonance, and an RF/Micro Wave Radiation method that converts electrical energy into microwaves and transmits them.

So far, the method using electromagnetic induction has been the mainstream, but recent experiments have been successfully conducted at home and abroad to transmit power wirelessly over a distance of tens of meters using microwaves. The world seems to be open.

The power transmission method by electromagnetic induction is a method of transmitting power between a primary coil and a secondary coil. When a magnet is moved in a coil, an induced current is generated. Using this, a magnetic field is generated at the transmitting end, and a current is induced according to the change of the magnetic field at the receiving end to create energy. This phenomenon is called a magnetic induction phenomenon, and a power transmission method using this phenomenon has excellent energy transmission efficiency.

As for the resonance method, in 2005, Professor Soljacic of MIT announced a system in which electricity is transmitted wirelessly even if it is several meters (m) away from the charging device by using the resonance method power transmission principle as the Coupled Mode Theory. The MIT team's wireless charging system uses the concept of physics in which when a tuning fork is struck, the wine glass next to it also vibrates at the same frequency as resonance. Instead of resonating sound, the research team resonated electromagnetic waves containing electrical energy. The resonant electrical energy is directly transmitted only when there is a device with a resonant frequency, and the unused portion is reabsorbed into the electromagnetic field instead of spreading into the air. .

As described above, conventional wireless power transmitters and wireless power receivers can generate differential signals to input/output between devices. In the case of using a differential signal, a 180-degree phase difference between two signals constituting the differential signal must be maintained, and it is required that the balance of the signals be maintained constant. However, in a conventional wireless charging system, an adaptive switch having a large loss is used to maintain a balance of differential signals for each node. In addition, when the position of the wireless power receiver is changed, a change in resonance impedance may occur. In this case, the waveform of the differential signal may be distorted according to the change in resonance impedance, and the balance may be broken. As the balance is broken, not only EMI increases, but also charging efficiency may decrease.

According to various embodiments of the present disclosure, a wireless power transmitter, a wireless power receiver, and a modulator for adjusting a differential signal to maintain a phase difference between two signals may be provided. In addition, the present invention may provide a wireless power transmitter capable of adjusting at least one of a phase and an amplitude of a single-ended signal.

According to various embodiments of the present disclosure, a wireless power transmitter for wirelessly charging a wireless power receiver may include a signal generator for generating a differential signal and a control signal for controlling phase adjustment of the differential signal. A modulator that adjusts the phase of A through a plurality of inverters, an amplifier that amplifies the adjusted differential signal with a preset gain, a resonator that transmits the amplified differential signal to the wireless power receiver, and a voltage of the amplified differential signal. and a sensing unit configured to sense current, and based on the sensed voltage and current, generating the control signal for controlling the phase difference between the signals included in the amplified differential signal to be a preset phase difference, to the modulator. It may include a control unit for outputting.

According to various embodiments of the present disclosure, a wireless power transmitter for wirelessly charging a wireless power receiver may include a signal generator generating a single-ended signal and a control signal for controlling phase adjustment of the single-ended signal. A modulator for adjusting the phase of a single-ended signal through at least one inverter, an amplifier for amplifying the adjusted single-ended signal with a preset gain, a resonator for transmitting the amplified single-ended signal to the wireless power receiver, A sensing unit that senses the voltage and current of the amplified single-ended signal, and the control signal for controlling the phase of the amplified single-ended signal to be a preset phase based on the sensed voltage and current, thereby generating the modulation It may include a control unit that outputs to the negative.

According to various embodiments of the present invention, an IC (integrated circuit) for controlling a phase of a differential signal transmitted to a wireless power receiver for wireless charging is configured by connecting at least one first inverter in series, and a differential signal A first phase control unit and at least one second inverter for adjusting the phase of a first signal included in the differential signal supplied to the chip through the at least one first inverter based on a control signal for controlling the phase adjustment of is connected in series and may include a second phase control unit configured to adjust a phase of a second signal included in the differential signal through the at least one second inverter based on the control signal.

According to various embodiments of the present invention, symmetry of a differential signal output from a wireless power transmitter is ensured, thereby increasing wireless charging efficiency and reducing EMI.

In addition, as at least one of the phase and amplitude of the single-ended signal output from the wireless power transmitter is controlled according to various embodiments of the present invention, wireless charging efficiency may be increased.

1 is a conceptual diagram for explaining the overall operation of a wireless charging system.
2 is a block diagram of a wireless power transmitter and a wireless power receiver according to an embodiment of the present invention.
3A-3C show block diagrams of wireless power transmitters according to various embodiments of the present invention.
4 shows a block diagram of a modulator according to various embodiments of the present invention.
5 illustrates a conceptual diagram of a phase control unit according to various embodiments of the present invention.
6 illustrates a conceptual diagram of a signal generator and a phase controller according to various embodiments of the present invention.
7 illustrates a conceptual diagram of a phase controller according to various embodiments of the present invention.
8 illustrates a conceptual diagram of a phase control unit according to various embodiments of the present invention.
FIG. 9A illustrates changes in time delay, ie, phase delay, of a square wave in a wireless power transmitter including CMOS process elements according to various embodiments of the present disclosure at a resonant frequency of 6.78 MHz.
FIG. 9B shows measurement results for explaining FIG. 9A.
10A to 10G show circuit diagrams of PA drivers according to various embodiments of the present invention.
11 illustrates waveforms of signals before and after noise removal through a PA driver according to various embodiments of the present invention.
12 is a diagram for explaining a method of detecting a positional change of a wireless power receiver in a wireless power transmitter according to various embodiments of the present disclosure.
13A to 13C show signal waveforms according to comparative examples.
14A and 14B are diagrams for explaining a method of notifying that a position of a wireless power receiver in a wireless power transmitter is out of a preset position according to various embodiments of the present disclosure.
15 is a configuration diagram of a current sensing circuit of a differential structure according to various embodiments of the present disclosure.
16 is a configuration diagram of an amplifier circuit connected to the current sensing circuit according to various embodiments of the present disclosure.
17 is a configuration diagram of a rectifier circuit unit according to various embodiments of the present disclosure.

Hereinafter, various embodiments of this document will be described with reference to the accompanying drawings. However, this is not intended to limit the technology described in this document to specific embodiments, and should be understood to include various modifications, equivalents, and/or alternatives of the embodiments of this document. . In connection with the description of the drawings, like reference numerals may be used for like elements.

In this document, expressions such as "has," "may have," "includes," or "may include" indicate the existence of a corresponding feature (eg, numerical value, function, operation, or component such as a part). , which does not preclude the existence of additional features.

In this document, expressions such as “A or B,” “at least one of A and/and B,” or “one or more of A or/and B” may include all possible combinations of the items listed together. . For example, “A or B,” “at least one of A and B,” or “at least one of A or B” (1) includes at least one A, (2) includes at least one B, Or (3) may refer to all cases including at least one A and at least one B.

Expressions such as "first," "second," "first," or "second," as used in this document may modify various elements, regardless of order and/or importance, and refer to one element as It is used only to distinguish it from other components and does not limit the corresponding components. For example, a first user device and a second user device may represent different user devices regardless of order or importance. For example, without departing from the scope of rights described in this document, a first element may be called a second element, and similarly, the second element may also be renamed to the first element.

A component (e.g., a first component) is "(operatively or communicatively) coupled with/to" another component (e.g., a second component); When referred to as "connected to", it should be understood that the certain component may be directly connected to the other component or connected through another component (eg, a third component). On the other hand, when an element (eg, a first element) is referred to as being “directly connected” or “directly connected” to another element (eg, a second element), the element and the above It may be understood that other components (eg, a third component) do not exist between the other components.

As used in this document, the expression "configured to" means "suitable for," "having the capacity to," depending on the circumstances. ," "designed to," "adapted to," "made to," or "capable of." The term "configured (or set) to" may not necessarily mean only "specifically designed to" hardware. Instead, in some contexts, the phrase "device configured to" may mean that the device is "capable of" in conjunction with other devices or components. For example, the phrase "a processor configured (or configured) to perform A, B, and C" may include a dedicated processor (eg, embedded processor) to perform the operation, or by executing one or more software programs stored in a memory device. , may mean a general-purpose processor (eg, CPU or application processor) capable of performing corresponding operations.

Terms used in this document are only used to describe a specific embodiment, and may not be intended to limit the scope of other embodiments. Singular expressions may include plural expressions unless the context clearly dictates otherwise. Terms used herein, including technical or scientific terms, may have the same meaning as commonly understood by a person of ordinary skill in the technical field described in this document. Among the terms used in this document, terms defined in a general dictionary may be interpreted as having the same or similar meaning as the meaning in the context of the related art, and unless explicitly defined in this document, an ideal or excessively formal meaning. not be interpreted as In some cases, even terms defined in this document cannot be interpreted to exclude the embodiments of this document.

1 is a conceptual diagram for explaining the overall operation of a wireless charging system. As shown in FIG. 1 , the wireless charging system includes a wireless power transmitter 100 and at least one wireless power receiver 110-1, 110-2, and 110-n.

The wireless power transmitter 100 may wirelessly transmit power 1-1, 1-2, and 1-n to at least one wireless power receiver 110-1, 110-2, and 110-n, respectively.

The wireless power transmitter 100 may form an electrical connection with the wireless power receivers 110-1, 110-2, and 110-n. For example, the wireless power transmitter 100 may transmit wireless power by radiating an electromagnetic field or a magnetic field. Here, the wireless power transmitter 100 may transmit wireless power based on an induction method or a resonance method.

Meanwhile, the wireless power transmitter 100 may perform bi-directional communication with the wireless power receivers 110-1, 110-2, and 110-n. In the case of out-of-band communication, the wireless power transmitter 100 and the wireless power receivers 110-1, 110-2, and 110-n transmit packets 2-1, 2-2, and 2- n) can be processed or transmitted and received. In particular, the wireless power receiver may be implemented as a mobile communication terminal, a PDA, a PMP, a smart phone, a wearable electronic device, and the like. In the case of in-band communication, the wireless power receivers 110-1, 110-2, and 110-n may perform load modulation, and the wireless power transmitter 100 detects a load change, so the wireless power receiver Reports of (110-1, 110-2, 110-n) can be obtained.

The wireless power transmitter 100 may wirelessly provide power to a plurality of wireless power receivers 110-1, 110-2, and 110-n. For example, the wireless power transmitter 100 may transmit power to a plurality of wireless power receivers 110-1, 110-2, and 110-n through a resonance method. When the wireless power transmitter 100 adopts the resonance method, the distance between the wireless power transmitter 100 and the plurality of wireless power receivers 110-1, 110-2, and 110-n may be a distance operating in an indoor environment. . Also, when the wireless power transmitter 100 adopts the electromagnetic induction method, the distance between the wireless power transmitter 100 and the plurality of wireless power receivers 110-1, 110-2, and 110-n may be preferably 10 cm or less. .

The wireless power receivers 110-1, 110-2, and 110-n may receive wireless power from the wireless power transmitter 100 to charge batteries included therein. In addition, the wireless power receivers 110-1, 110-2, and 110-n transmit a signal requesting wireless power transmission, information necessary for wireless power reception, wireless power receiver status information, or wireless power transmitter 100 control information. It can be transmitted to the wireless power transmitter 100.

In addition, the wireless power receivers 110-1, 110-2, and 110-n may transmit messages indicating respective charging states to the wireless power transmitter 100 in an in-band or out-of-band manner.

The wireless power transmitter 100 may include a display means such as a display, and the wireless power receivers 110-1 and 110-n based on messages received from each of the wireless power receivers 110-1, 110-2, and 110-n. 110-2, 110-n) Each state can be displayed. In addition, the wireless power transmitter 100 may display an estimated time until each of the wireless power receivers 110-1, 110-2, and 110-n is completely charged.

2 is a block diagram of a wireless power transmitter and a wireless power receiver according to an embodiment of the present invention.

As shown in FIG. 2 , the wireless power transmitter 200 may include a power transmission unit 211 , a control unit 212 and a communication module 213 . In addition, the wireless power receiver 250 may include a power receiver 251, a controller 252, and a communication module 253.

The power transmitter 211 may provide power required by the wireless power receiver 200 and may provide power to the wireless power receiver 250 wirelessly. Here, the power transmission unit 211 may supply power in the form of an AC waveform, or may supply power in the form of a DC waveform while converting it into an AC waveform using an inverter and supplying the power in the form of an AC waveform.

In addition, the power transmitter 211 may provide an AC waveform to the wireless power receiver 250 . The power transmission unit 211 may further include a resonant circuit or an induction circuit, and thus may transmit or receive predetermined electromagnetic waves. When the power transmission unit 211 is implemented as a resonant circuit, the inductance L of the loop coil of the resonant circuit may be changeable. Meanwhile, those skilled in the art will easily understand that the power transmission unit 211 is not limited as long as it is a means capable of transmitting an electromagnetic field or a magnetic field.

The controller 212 may control overall operations of the wireless power transmitter 200 . The controller 212 or the controller 252 may control the overall operation of the wireless power transmitter 200 or the wireless power receiver 250 by using an algorithm, program, or application required for control read from a memory (not shown). there is.

The communication module 213 may communicate with the wireless power receiver 250 or another electronic device in a predetermined manner. The communication module 213 includes the communication module 253 of the wireless power receiver 250 and near field communication (NFC), Zigbee communication, infrared communication, visible ray communication, Bluetooth communication, BLE (bluetooth low energy) method, MST (magnetic Communication may be performed using a secure transfer method or the like. On the other hand, the above-described communication method is merely exemplary, and the scope of rights of the embodiments of the present invention is not limited to a specific communication method performed by the communication module 213.

The power receiver 251 may receive wireless power from the power transmitter 211 based on an induction method or a resonance method.

3A-3C show block diagrams of wireless power transmitters according to various embodiments of the present invention.

Referring to FIG. 3A , the wireless power transmitter 300 may include a signal conditioning unit 310, an amplifier 320, a matching unit 330, and a resonance unit 340.

The signal conditioning unit 310 includes a current sensing circuit 311, a voltage sensing circuit 312, ADCs 313 and 314, a controller 315, a modulator 316, a power amplifier (PA) driver 317, and signal generation. may include section 318 . The signal conditioning unit 310 may be implemented as an IC (integrated circuit), but the type of implementation is not limited.

In the embodiment of FIG. 3A , the signal adjuster 310 may generate a differential signal using the signal generator 318 and output the generated differential signal to the amplifier 320 . For example, the signal generator 318 may include a power providing means capable of generating a single-ended signal. The power providing unit may be implemented as a battery included in the wireless power transmitter 300 or may be implemented as a power interface that receives power from the outside. When the power providing unit is implemented as a battery, the signal generating unit 318 may further include an inverter that converts DC power output from the battery into AC. When the power providing unit is implemented as a power interface, the power providing unit may receive AC power from the outside, or may receive DC power and convert it to AC, in which case it may further include an inverter. there is.

Meanwhile, the signal generator 318 may generate a differential signal from a single-ended signal. The signal generator 318 may include, for example, a branch rail connected in parallel to a rail receiving a single-ended signal, and may include an inverted signal generator such as an inverter located on the branch rail. Accordingly, a first signal having the same phase as the single-ended signal can be output from one rail of the signal generator 318, and a phase difference of 180 degrees from the single-ended signal can be obtained from the branch rail through the inverted signal generator. A second signal may be output. Accordingly, the signal generator 318 may generate a differential signal composed of the first signal and the second signal having a phase difference of 180 degrees from each other.

The modulator 316 may adjust at least one of the differential signals. The modulator 316 may adjust at least one of an amplitude and a phase of at least one of the differential signals. In one embodiment, the modulator 316 may adjust the phase of at least one of the differential signals by delaying at least one of the differential signals. The modulator 316 may include a DC/DC converting unit or a voltage divider, and accordingly, the amplitude of at least one of the differential signals may be adjusted. Meanwhile, in another embodiment, the amplitude of at least one of the differential signals may be adjusted by adjusting the driving voltage VDD of the amplifier 320 instead of the modulator 316 . In this case, a DC/DC converting unit or a voltage divider may be disposed on a rail to which the driving voltage VDD of the amplifier 320 is applied.

The PA driver 317 can perform current pumping on the differential signal output from the modulator 316, and accordingly, the On/Off Delay time of the input signal of the amplifier 320 is shortened, and the input signal Noise of is removed, and the input signal from which the noise is removed may be amplified with a preset gain. In various embodiments of the present invention, the input signal may be a differential signal or a single-ended signal.

In various embodiments of the present invention, PA driver 317 may include at least one inductor. The inductor can prevent an abrupt change in current, and accordingly, when the input differential signal includes a peak, the PA driver 17 can exclude the peak and output the signal. . As will be described in more detail later, the relative position of the wireless power receiver to the wireless power transmitter may be changed. Since the wireless power receiver may also include an inductor, the wireless power transmitter and the wireless power receiver may be circuit-coupled, and thus impedance may be changed due to a change in relative position. Depending on the impedance change, a peak may be included in the differential signal input to the PA driver 317, and the occurrence of the peak may be prevented by an inductor included in the PA driver 317. In addition, when the wireless power transmitter operates based on the A4WP standard method, for example, a relatively high frequency of 6.78 MHz may be used as a resonant frequency. Alternatively, even when performance is changed according to the impedance of the resonator, antenna, or load, the PA driver 317 including the inductor has characteristics that are robust to changes, and more stable signal amplification may be possible. In various embodiments of the present invention, the PA driver 317 may further include a capacitor or an FET device in addition to the inductor, and various embodiments will be described in more detail with reference to FIGS. 10A to 10G .

The amplifier 320 may amplify the differential signal output from the PA driver 317 with a preset gain. The amplifier 320 may be implemented as a class-D or class-E amplifier, for example. The amplifier 320 may perform amplification using the driving voltage VDD. Meanwhile, as described above, in one embodiment, the driving voltage VDD may be changed. For example, the wireless power transmitter 300 may include a device capable of changing voltage, such as a DC/DC converter or a voltage divider disposed on a rail providing a driving voltage VDD to the amplifier 320 . When it is determined that it is necessary to adjust the amplitude of the differential signal output from the amplifier 320, the wireless power transmitter 300 operates a DC/DC converter or a voltage divider to change the gain of the amplifier 320 to output The amplitude of the differential signal can be adjusted.

The matching unit 330 may include at least one of various elements for impedance matching, for example, at least one inductor and at least one capacitor. As described above, the position of the wireless power receiver relative to the wireless power transmitter is variable, and thus, when the wireless power receiver is disposed on the wireless power transmitter, it may have various impedances. The wireless power transmitter 300 may increase wireless charging efficiency through impedance matching.

The resonator 340 may generate an electromagnetic field using a differential signal from the amplifier 320 and radiate it to the outside. When the wireless power transmitter 300 operates based on the A4WP method, the resonator 340 may be designed to have a resonant frequency of 6.78 MHz, and may generate an electromagnetic field having a resonant frequency and radiate it to the outside. . The resonance unit 340 may include at least one inductor and at least one capacitor constituting a resonance circuit.

The current sensing circuit 311 may sense electrical characteristics of the first signal at the first input terminal of the resonator 340, for example, a current value. The voltage sensing circuit 312 may sense electrical characteristics of the second signal at the second input terminal of the resonator 340, for example, a voltage value. Meanwhile, in various embodiments of the present invention, the current sensing circuit 311 may be connected to the second input terminal of the resonance unit 340, and the voltage sensing circuit 312 may be connected to the first input terminal of the resonance unit 340. . In addition, in another embodiment of the present invention, each of the two current sensing circuits may be connected to the first input terminal and the second input terminal of the resonator 340, respectively, and each of the two voltage sensing circuits of the resonator 340 It may be connected to each of the first input terminal and the second input terminal.

The ADC 313 may convert an analog value of the current value sensed by the current sensing circuit 311 into a digital value and output the converted digital value to the controller 315 . The ADC 314 may convert an analog value of the voltage value sensed by the voltage sensing circuit 312 into a digital value and output the converted digital value to the controller 315 .

The controller 315 may determine modulation information of the signal using the current value of the first signal and the voltage value of the second signal. For example, the controller 315 may determine a phase difference between the first signal and the second signal using the current value of the first signal and the voltage value of the second signal. The controller 315 may determine, for example, that the phase difference between the first signal and the second signal is 183 degrees. The controller 315 may determine modulation information of a signal for maintaining a phase difference of 180 degrees between the first signal and the second signal. For example, the controller 315 may determine modulation information for delaying the second signal by t. The controller 315 may output a control signal corresponding to the determined modulation information to the modulator 316 . The modulator 316 may delay the second signal by t based on the input control signal, and thus the phase difference between the first signal and the second signal may be maintained at a predetermined value, for example, 180 degrees. there is. In another embodiment, the control unit 315 may determine, for example, that the amplitude of the second signal is A' from a digital value from the ADC 314. The control unit 315 may determine modulation information for adjusting the amplitude of the second signal to A, and output a control signal corresponding thereto. For example, when the modulator 316 adjusts the amplitude, the control unit 315 may output a control signal for adjusting the amplitude to the modulator 316 . In another example, when the amplifier 320 adjusts the amplitude, the control unit 315 sends a control signal to a device such as a DC/DC converter or a voltage divider disposed on a rail to which the driving voltage of the amplifier 320 is applied. can output Accordingly, the wireless power transmitter can monitor and control a change in impedance, a mismatch of a differential signal, or signal distortion in real time, thereby increasing charging efficiency and reducing EMI.

As described above, the modulator 316 maintains the phase difference between the first signal and the second signal at a predetermined value or the amplitude of at least one of the first signal and the second signal to maintain a predetermined value, Differential signals can be tuned. Accordingly, the first signal and the second signal constituting the differential signal have an undistorted waveform while having a predetermined phase difference despite the impedance change, so that relatively low EMI and high charging efficiency can be created. .

When the amplifier 320 adopts a class D, E, or F switching method, the amplifier 320 may use a square wave signal capable of turning on/off a power device as an input signal. For differential signals of square waves, the two signals must maintain a monotonic, continuous phase difference. The number of bits of digital control varies according to the maximum range of the phase difference to be varied and the minimum change width of the phase difference. When the maximum range is large and the minimum change width is very small and precise, the number of phase steps increases and the number of control bits increases. Conversely, when the maximum range is small and the minimum change width is relatively large, fewer control bits are required. Control of the phase must be continuous and monotonically increasing or decreasing monotonically. It should be monotonic so that discontinuities or control instability do not occur when phase difference control is performed through code adjustment during digital control. However, for phase control, it should be designed as a low-power circuit for power efficiency of the entire transmission unit while having the ability to sufficiently drive the input stage of the amplifier 320. Therefore, for low power characteristics, a signal adjusting unit 310 may be provided that outputs a square wave whose phase control is continuous and controlled in a monotonically increasing form while controlling the phase only with digital circuits. In addition, the signal adjusting unit 310 maximizes the efficiency of the amplifier 320 by controlling the power of logic circuits such as inverters that generate PWM the amplitude of the PWM signal, which is an input signal that greatly affects the efficiency of the amplifier 320. can be provided.

In various embodiments of the present invention, the amplifier 320, the matching unit 330, and the resonance unit 340 may be disposed outside the signal conditioning unit 310. In addition, the power providing unit 318 may also be disposed outside the signal conditioning unit 310 or included in the signal conditioning unit 310 according to embodiments. More specifically, when the power supply unit 318 is implemented as a battery, the power supply unit 318 may be disposed outside the signal control unit 310 . When the power providing unit 318 is implemented as a power interface, the power providing unit 318 may be included in the signal conditioning unit 310 . Elements disposed outside the signal adjusting unit 310 may be implemented as analog elements. Meanwhile, in various embodiments of the present invention, the wireless power transmitter may sense not only the input terminal of the resonator 340, but also current values and voltage values at various locations.

3B shows a block diagram of a wireless power transmitter using a single-ended signal according to various embodiments of the present invention.

Referring to FIG. 3B , the wireless power transmitter 300 may include a signal conditioning unit 350, an amplifier 360, a matching unit 370, and a resonance unit 380.

The signal conditioning unit 350 may include a sensing circuit 351, an ADC 353, a control unit 355, a modulator 356, a power amplifier (PA) driver 357, and a signal generator 358. The signal conditioning unit 350 may be implemented as an integrated circuit (IC), but there is no limitation on the type of implementation.

In the embodiment of FIG. 3B , the signal conditioning unit 350 may generate a single-ended signal and output the generated single-ended signal to the amplifier 360 . The signal generator 358 may generate a single-ended signal. For example, the signal generator 358 may include a power providing means capable of generating a single-ended signal. The power providing unit may be implemented as a battery included in the wireless power transmitter 300 or may be implemented as a power interface that receives power from the outside. When the power providing means is implemented as a battery, the signal generating unit 358 may further include an inverter that converts DC power output from the battery into AC. When the power providing unit is implemented as a power interface, the power providing unit may receive AC power from the outside, or may receive DC power and convert it to AC, in which case it may further include an inverter. there is.

The modulator 356 may condition a single-ended signal. The modulator 356 may adjust at least one of an amplitude and a phase of the single-ended signal. In one embodiment, the modulator 356 may adjust the phase of the single-ended signal by delaying the single-ended signal. The modulator 356 may include a DC/DC converter or a voltage divider, and accordingly, the amplitude of the single-ended signal may be adjusted. Meanwhile, in another embodiment, the amplitude of the single-ended signal may be adjusted by adjusting the driving voltage VDD of the amplifier 360 instead of the modulator 356 . In this case, a DC/DC converting unit or a voltage divider may be disposed on a rail to which the driving voltage VDD of the amplifier 360 is applied.

The PA driver 357 may perform current pumping on the differential signal output from the modulator 356, and accordingly, the On/Off Delay time of the input signal of the amplifier 360 is shortened, and the input signal Noise of is removed, and the input signal from which the noise is removed may be amplified with a preset gain. In various embodiments of the present invention, the input signal may be a differential signal or a single-ended signal.

In various embodiments of the present invention, PA driver 357 may include at least one inductor. The inductor can prevent an abrupt change in current, and accordingly, when the input differential signal includes a peak, the PA driver 357 can exclude the peak and output the signal. .

The amplifier 360 may amplify the single-ended signal output from the PA driver 357 with a preset gain. Amplifier 360 may be implemented as a class-D or class-E amplifier, for example. The amplifier 360 may perform amplification using the driving voltage VDD. Meanwhile, as described above, in one embodiment, the driving voltage VDD may be changed. For example, the wireless power transmitter 300 may include a device capable of changing voltage, such as a DC/DC converter or a voltage divider disposed on a rail providing a driving voltage VDD to the amplifier 360 . When it is determined that the amplitude of the single-ended signal output from the amplifier 360 needs to be adjusted, the wireless power transmitter 300 may change the gain of the amplifier 360 by operating a DC/DC converter or voltage divider. It is possible to adjust the amplitude of the output single-ended signal.

The matching unit 370 may include at least one of various elements for impedance matching, for example, at least one inductor and at least one capacitor. As described above, the position of the wireless power receiver relative to the wireless power transmitter is variable, and thus, when the wireless power receiver is disposed on the wireless power transmitter, it may have various impedances. The wireless power transmitter 300 may increase wireless charging efficiency through impedance matching.

The resonator 380 may generate an electromagnetic field using a single-ended signal from the amplifier 360 and radiate it to the outside. When the wireless power transmitter 300 operates based on the A4WP method, the resonator 380 may be designed to have a resonant frequency of 6.78 MHz, and may generate an electromagnetic field having a resonant frequency and radiate it to the outside. . The resonance unit 380 may include at least one inductor and at least one capacitor constituting a resonance circuit.

The sensing circuit 351 may sense electrical characteristics of the single-ended signal at the input terminal of the resonator 380, for example, at least one of a current value and a voltage value.

The ADC 353 may convert at least one analog value of the current value and the voltage value sensed by the current sensing circuit 351 into a digital value and output the converted digital value to the controller 355 .

The controller 355 may determine modulation information of the signal using at least one of a current value and a voltage value of the single-ended signal. For example, the controller 355 may determine the phase of the single-ended signal using at least one of a current value and a voltage value of the single-ended signal. The control unit 355 may determine modulation information of the signal to maintain the phase of the single-ended signal at a predetermined value. For example, the controller 355 may determine modulation information for delaying the single-ended signal by t. The controller 355 may output a control signal corresponding to the determined modulation information to the modulator 356 . The modulator 356 may delay the single-ended signal by t based on the input control signal, and accordingly, the phase of the single-ended signal may be maintained at a preset value. In another embodiment, the controller 355 may determine, for example, that the amplitude of the single-ended signal is A' from the digital value from the ADC 354. The control unit 355 may determine modulation information for adjusting the amplitude of the single-ended signal to A, and output a control signal corresponding thereto. For example, when the modulator 356 adjusts the amplitude, the control unit 355 may output a control signal for adjusting the amplitude to the modulator 356 . In another example, when the amplifier 360 adjusts the amplitude, the control unit 355 sends a control signal to a device such as a DC/DC converter or a voltage divider disposed on a rail to which the driving voltage of the amplifier 360 is applied. can output

As described above, the modulator 356 may adjust the single-ended signal so that the phase of the single-ended signal maintains a preset value or the amplitude of the single-ended signal maintains a preset value.

In various embodiments of the present invention, the amplifier 360, the matching unit 370, and the resonance unit 380 may be disposed outside the signal conditioning unit 350. In addition, the signal generating unit 358 may also be disposed outside the signal adjusting unit 350 or included in the signal adjusting unit 350 according to embodiments. More specifically, when the power supply unit 358 is implemented as a battery, the power supply unit 358 may be disposed outside the signal control unit 350 . When the power providing unit 358 is implemented as a power interface, the power providing unit 358 may be included in the signal conditioning unit 350 .

Referring to FIG. 3C, the wireless power transmitter 300 includes a current sensing circuit 311, a voltage sensing circuit 312, ADCs 313 and 314, a controller 315, a modulator 316, and a power amplifier (PA). A driver 317, a signal generator 318, an amplifier 320, a matching unit 330, and a resonator 340 may be included.

As described in FIG. 3A , at least one of the components included in the wireless power transmitter 300 may be implemented through one IC, such as one signal control unit 310. Also, as shown in FIG. 3C, each may be implemented with separate hardware (eg, an analog device, an integrated circuit (IC), etc.). For example, the modulator 316 or the PA driver 317 may be configured with hardware such as a separate IC.

In addition, although not shown, each component included in the wireless power transmitter using a single-ended signal shown in FIG. 3B may also be implemented as separate hardware.

Since each component shown in FIG. 3C is the same as that described in FIG. 3A, a detailed description thereof will be omitted.

4 shows a block diagram of a modulator according to various embodiments of the present invention.

The modulator 410 may include a voltage adjuster 411 , an amplitude controller 412 and a phase controller 413 . In various embodiments of the present invention, the modulator 410 can digitally control the phase of the differential signal, so that various digital control algorithms can be applied through an MCU or FPGA, and continuity of correction and phase change can be guaranteed

The phase controller 413 may adjust the phase of at least one of the differential signals. In various embodiments of the present invention, the phase controller 413 may include a delay element capable of delaying at least one signal. The phase controller 413 may delay at least one signal for a delay time determined based on a control signal from the controller. For example, FIG. 5 shows a conceptual diagram of a phase control unit according to various embodiments of the present invention. Referring to FIG. 5 , the phase controller 500 may include a plurality of delay elements 511 to 515. Some of the delay elements 511 to 515 may be controlled to be in an on state, and a signal may be delayed by the delay time Δt. The control unit may determine the delay time Δt, determine the number of delay elements to be controlled to be turned on based on the determined delay time Δt, and output a control signal. Accordingly, the phase controller 413 may determine the first delay device corresponding to the determined number of delay devices among the plurality of delay devices 511 to 515 . The phase controller 413 may adjust the phase of the signal by delaying the signal by the determined delay time Δt by outputting an output of the first delay device.

In various embodiments of the present invention, the phase controller 413 may delay at least one of the first signal and the second signal, and the phase difference between the first signal and the second signal may be maintained at 180 degrees. .

Alternatively, when the wireless power transmitter uses a single-ended signal rather than a differential signal, the control unit may output a control signal that causes the phase of the single-ended signal to have a predetermined value. The phase control unit 413 may control at least a portion of the delay elements to be in an on state based on the control signal, delay the single-ended signal by the delay time Δt, and thereby change the phase of the single-ended signal to a predetermined value. can have it

The amplitude controller 413 may adjust the amplitude of at least one signal of the differential signal using a driving voltage input from the voltage controller 411 . For example, the amplitude controller 413 may adjust the amplitude of at least one signal of the differential signal based on the magnitude of the driving voltage input from the voltage controller 411 . For example, the control unit may determine that the amplitude of at least one signal has a difference from a preset value, and accordingly output a control signal for causing the amplitude of at least one signal to have a preset value. The voltage adjusting unit 411 may adjust the amplitude of the differential signal or the single-ended signal output from the amplitude controlling unit 412 by adjusting the driving voltage of the amplitude controlling unit 412 based on the control signal output from the controlling unit.

As described above, the modulator 410 may adjust at least one of a phase and an amplitude of a differential signal or a single-ended signal.

The amplifier 420 may be implemented as, for example, a class D or E amplifier, and may include inductors 421 and 422 and FETs 423 and 424 as shown. The first signal modulated by the modulator 410 may be input to the gate of the FET 423 , and the second signal modulated by the modulator 410 may be input to the gate of the FET 414 . Inductors 421 and 422 may be connected to an output terminal of the amplifier 420, and each of the inductors 421 and 422 may be connected to drains of the FETs 423 and 424, respectively.

In FIG. 4, after the phase of the differential signal input to the modulator 410 is adjusted through the phase control unit 413, the amplitude of the phase-adjusted differential signal is adjusted through the amplitude control unit 412, but this description It is only an example for the purpose of, but is not limited thereto. After the amplitude of the differential signal input to the modulator 410 is adjusted through the amplitude control unit 412, the phase of the differential signal whose amplitude is adjusted may be adjusted through the phase control unit 413. Each of the signals included in the differential signal of which at least one of phase and amplitude is adjusted through the modulator 410 may be output to an input terminal of the amplifier 420 .

6 illustrates a conceptual diagram of a signal generator and a phase controller according to various embodiments of the present invention.

Referring to FIG. 6 , the phase controller may include a first phase delay circuit 630 , a second phase delay circuit 631 , a first buffer 640 and a second buffer 641 . The signal generating unit outputting the differential signal to the phase controller may include a differential signal generating unit 610 , a first comparator 620 and a second comparator 621 .

The differential signal generator 610 may receive a single-ended signal and output a differential signal. For example, the differential signal generator 610 may include a single to differential (S2D) circuit, and may generate and output a differential signal using the S2D circuit. The first signal and the second signal constituting the differential signal may have a phase difference of 180 degrees.

Each of the first signal and the second signal constituting the generated differential signal may be converted into a square wave form through a first comparator 620 and a second comparator 621 . Since the input signal is a differential signal having a difference of 180 degrees, the outputs of the two comparators 620 and 621 become differential square waves having a phase difference of 180 degrees.

The phase control unit may include a first phase control unit and a second phase control unit configured to adjust phases of the first signal and the second signal respectively supplying the differential signal. The first phase controller may include a first phase delay circuit 630 and a first buffer 640, and the second phase controller may include a second phase delay circuit 631 and a second buffer 641. there is.

Each of the first phase delay circuit 630 and the second phase delay circuit 631 may include at least one delay element connected in series. For example, the first phase delay circuit 630 is configured by connecting at least one first delay element in series among a plurality of delay elements included in the phase controller, and the at least one first delay element is The phase of the first signal may be adjusted by delaying the phase of the first signal. The second phase delay circuit 631 is configured by connecting at least one second delay element in series among a plurality of delay elements included in the phase controller, and the second delay element is connected through the at least one second delay element. The phase of the second signal may be adjusted by delaying the phase of the signal.

The first phase delay circuit 630 and the second phase delay circuit 631 may delay at least one of the square wave of the first signal and the square wave of the second signal. In various embodiments of the present invention, the first phase delay circuit 630 and the second phase delay circuit 631 may be driven in a digital dimension, and the signal is continuously and monotonically increased according to an external digital control input. phase can be controlled. In the embodiment of FIG. 6 , the first phase delay circuit 630 and the second phase delay circuit 631 may be implemented as a structure including an analog switch. Depending on the position where the analog switch is connected, the number of delay elements operating in the on state in each of the first phase delay circuit 630 and the second phase delay circuit 631 may be determined, and accordingly, the delay time td is can be determined

The first buffer 640 and the second buffer 641 may output the phase-adjusted first and second signals after temporarily storing them. Each of the phase-adjusted first and second signals may be output to an input terminal of an amplifier or may be output to an amplitude control unit for adjusting an amplitude of a differential signal.

On the other hand, if the Vref voltage, which is the comparison voltage of the comparators 620 and 621, is adjusted, the reference voltage moving between the voltage of '1' and the voltage of '0' is different, so that the duty cycle of the square wave can be adjusted.

7 illustrates a conceptual diagram of a phase controller according to various embodiments of the present invention.

7 illustrates a conceptual diagram of a phase controller according to various embodiments of the present invention. As shown in FIG. 7 , the phase controller 710 may include at least one inverter 711 , 712 , 713 and a multiplexer (MUX) 720 . If the number of inverters 711, 712, and 713 is N, the number of channels of the multiplexer may be N-1. The multiplexer 720 may determine an inverter to be controlled in an on state based on an input control signal, and output the output of the determined inverter.

Hereinafter, it is assumed that the first signal is adjusted by the first phase controller and the second signal is adjusted by the second phase controller. The first phase controller may include at least one first inverter and a first multiplexer, and the second phase controller may include at least one second inverter and a second multiplexer. In addition, it is assumed that the first phase controller controls up to the m-th first inverter to be turned on based on the control signal, and the second phase controller controls up to the n-th second inverter to be turned on based on the control signal.

When the delay time of each of the first inverter and the second inverter is td, the output of the mth first inverter becomes a signal having a time delay of m × td compared to the input signal. The first signal may have a time delay of m × td by passing through m inverters. In addition, the output of the mth inverter corresponding to the first signal delayed by m × td may be output through the multiplexer.

In addition, the second signal may have a time delay of n × td by passing through n inverters. An output of the n-th inverter corresponding to the second signal delayed by n × td may be output through a multiplexer. In this case, the time difference between the output (Vout,p) of the first phase control unit, which is the output of the m-th inverter, and the output (Vout,n) of the second phase control unit, which is the output of the n-th inverter, is T/2 due to the phase difference of 180 degrees. In addition to the time difference of (n-m) × td, the time difference of T / 2 + (n-m) td can be added. A differential signal composed of the first signal and the second signal may be generated. At this time, if n and m are controlled by digital control, a differential signal of a phase difference that continuously monotonically increases and decreases may be generated. Here, the maximum range of phase control is the difference between the case where the output of the first phase controller is set to the minimum delay and the output of the second phase controller is set to the maximum delay and vice versa, so (2Ntd/T) × 360° is This is the maximum controllable phase difference control range. Here, it is assumed that N is the number of inverters included in the phase control unit, and the number of inverters included in each of the first phase control unit and the second phase control unit is equal to N. Even when the number of inverters included in each of the first phase control unit and the second phase control unit is different, a maximum controllable phase difference control range may be determined in the same manner.

In addition, the minimum controllable phase difference control precision is td/T × 360°, as the number of inverters increases, the phase control precision increases. That is, the phase control precision can be determined by adjusting the time delay of the inverter, and the maximum phase control range can be adjusted by adjusting the number of inverters. In order to control N number, you need to input k bit control signal to the multiplexer by digital control from outside. Then, the N outputs of each inverter can be selectively output through the multiplexer.

8 illustrates a conceptual diagram of a phase control unit according to various embodiments of the present invention.

As shown in FIG. 8 , the phase controller may include at least one inverter 810 or 811 . The phase controller of FIG. 8 may include a capacitor disposed between the output terminal of the inverter 810 and the input terminal of the inverter 811 and the ground terminal. For example, a capacitor 820 having one end connected between the inverter 810 and the inverter 811 and the other end connected to ground may be included. Capacitor 820 can charge and discharge, so it can additionally delay the signal. Meanwhile, in various embodiments of the present invention, the capacitor 820 may be implemented as a variable capacitor.

The capacitance of the capacitor may be adjusted based on a control signal generated by a controller. The phase control unit determines one of the at least one inverter based on the control signal, outputs an output of the determined inverter, and controls the phase of the differential signal more precisely by adjusting the capacitance of the capacitor. can

FIG. 9A illustrates changes in time delay, ie, phase delay, of a square wave in a wireless power transmitter including CMOS process elements according to various embodiments of the present disclosure at a resonant frequency of 6.78 MHz.

FIG. 9A shows a change in time delay, ie, phase delay, of a square wave in a wireless power transmitter including CMOS process elements according to various embodiments of the present invention at a resonant frequency of 6.78 MHz. It can be seen that the efficiency of the amplifier is affected not only by the amplifier's power supply VDD and phase, but also by the amplitude of the PWM signal, which is the amplifier's input signal.

9A is a graph showing a change in magnitude of each differential output voltage according to phase difference control. In FIG. 9A , a correlation between a phase difference control code and differential output voltages VTXP and VTXN (P denotes positive and N denotes negative) is shown. Here, the phase difference control code may refer to a digital code capable of controlling a phase difference between differential outputs.

Referring to FIG. 9A , it can be confirmed that as the phase difference control code increases, VTXP increases and VTXN decreases, and as the phase difference control code decreases, VTXP decreases and VTXN increases. Therefore, the symmetry of the output differential signal can be guaranteed by sensing the magnitudes of the VTXP and VTXN and controlling the phase difference according to the respective magnitudes of the control unit.

FIG. 9B shows measurement results for explaining FIG. 9A. Referring to FIG. 9B , it can be seen that the efficiency of the amplifier changes as the amplitude of the PWM is changed to 3V/3.2V/3.4V. Therefore, it is necessary to optimize the power efficiency by controlling the amplitude of the PWM signal. To implement this, in general, logic circuits such as inverters or EXORs can be used to create PWM signals of power amplifiers. can That is, the power of the logic circuit is also controlled simultaneously with the phase control to optimize the efficiency of the power amplifier.

9B is a graph showing that the efficiency of the amplifier changes according to the amplitude of the driving voltage. Referring to FIG. 9B , since an optimal amplitude for obtaining relatively high power efficiency exists, the wireless power transmitter may process a signal to have an optimal amplitude. More specifically, when the amplitude of the detected signal does not correspond to the optimal amplitude, the control unit may adjust the amplitude of the output differential signal or single-ended signal by performing amplitude control.

10A to 10G show circuit diagrams of PA drivers according to various embodiments of the present invention. In various embodiments of the present disclosure, when harmonics having a high instantaneous peak current are generated in the wireless power transmitter, EMI radiation may be reduced by attenuating the inductor. In addition, when a MOS or BJT circuit is included in a wireless power transmitter, a capacitor is disposed between the gate-drain or base-collector of the current source circuit to enable feedback, thereby mitigating the peak current of harmonics. . In addition, the wireless power transmitter may include a complementary element such as CMOS, and may be operated at low power by the complementary element of NMOS and PMOS. For example, when a signal is not input by configuring an output or driving circuit having an inverter structure, operation at low power may be possible by preventing current from flowing.

Referring to FIG. 10A , the PA driver may include a plurality of transistors 1010 , 1011 , 1020 , and 1021 and inductors 1030 and 1031 . For example, the drain terminal of the first P-MOSFET 1011 is connected to the drain terminal of the first N-MOSFET 1010, and the first N-MOSFET 1010 and the first P-MOSFET 1011 are respectively A first signal among differential signals may be received through the gate. In addition, the first N-MOSFET 1010 and the first P-MOSFET 1011 may process the first signal and output a signal having a voltage of V0+.

The drain terminal of the second P-MOSFET 1021 is connected to the drain terminal of the second N-MOSFET 1020, and the second N-MOSFET 1020 and the second P-MOSFET 1021 are connected through respective gates. Of the differential signals, a second signal may be input. The second N-MOSFET 1020 and the second P-MOSFET 1021 may process the second signal and output a signal having a voltage of V0-.

In addition, a first inductor 1031 may be connected to the source of the first P-MOSFET 1011 and the source of the second P-MOSFET 1021, and the source of the first N-MOSFET 1010 and the source of the second N-MOSFET 1021. The second inductor 1030 may be connected to the source of the MOSFET 1020 .

In general, since a wireless power transmitter transmits relatively large power, relatively large voltage swings and current swings may occur within the wireless power transmitter. Accordingly, a large AC current momentarily flows in the wireless power transmitter, which may cause a problem in that a large noise signal of high frequency is radiated or conducted. In particular, when the wireless power transmitter uses a class D or E amplifier operating by switching, since a voltage signal is converted from 0V to VDD or from VDD to 0V in a square wave, a relatively large peak current may occur. The generated peak current may flow to a ground terminal for grounding of the PA driver or a driving power input terminal, causing power supply noise, and power supply noise may be transmitted through other circuits and substrates, thereby intensifying the noise problem.

Since the source or emitter terminals of the plurality of transistors (1010, 1011, 1020, 1021) are connected to each other and become common, peak currents of opposite signs occur at the instantaneous transition of the input voltage and can be offset, resulting in peak current noise A signal may be blocked from being transferred to a ground terminal or a driving power input terminal of the PA driver. The peak current may be removed by the inductors 1030 and 1031 connected in series to the ground terminal and the driving power input terminal of the PA driver.

10b to 10d show circuit diagrams of a PA driver further comprising a transistor current source. In the embodiment of FIG. 10B , a third N-MOSFET 1040 may be disposed between the 1 N-MOSFET 1010 and the second N-MOSFET 1020 . For example, sources of the first N-MOSFET 1010 and the second N-MOSFET 1020 may be connected to the drain of the third N-MOSFET 1040 . The second inductor 1030 may be connected to the source of the third N-MOSFET 1040 . In the embodiment of FIG. 10C , a third P-MOSFET 1041 may be disposed between the first P-MOSFET 1011 and the second P-MOSFET 1021 . For example, the drain of the third P-MOSFET 1041 may be connected to the source of each of the first P-MOSFET 1011 and the second P-MOSFET 1021 . The first inductor 1031 may be connected to the source of the third P-MOSFET 1041 . In the embodiment of FIG. 10D , sources of the first N-MOSFET 1010 and the second N-MOSFET 1020 may be connected to the drain of the third N-MOSFET 1040 . The second inductor 1030 may be connected to the source of the third N-MOSFET 1040 . In addition, the drain of the third P-MOSFET 1041 may be connected to the source of each of the first P-MOSFET 1011 and the second P-MOSFET 1021 . The first inductor 1031 may be connected to the source of the third P-MOSFET 1041 .

10e to 10g show circuit diagrams of the PA driver further comprising a transistor current source and a capacitor. In the embodiment of FIG. 10E , sources of the first N-MOSFET 1010 and the second N-MOSFET 1020 may be connected to the drain of the third N-MOSFET 1040 . The second inductor 1030 may be connected to the source of the third N-MOSFET 1040 . Meanwhile, the first capacitor 1050 may be disposed between the source of each of the first N-MOSFET 1010 and the second N-MOSFET and the gate of the third N-MOSFET 1040 . For example, sources of the first N-MOSFET 1010 and the second N-MOSFET 1020 may be connected to one end of the first capacitor 1050 . The gate of the third MOSFET 1040 may be connected to the other end of the first capacitor 1050 . In the embodiment of FIG. 10F , the drain of the third P-MOSFET 1041 may be connected to the source of each of the first P-MOSFET 1011 and the second P-MOSFET 1021 . The first inductor 1031 may be connected to the source of the third P-MOSFET 1041 . Meanwhile, the second capacitor 1051 may be disposed between the source of each of the first P-MOSFET 1011 and the second P-MOSFET 1021 and the gate of the third P-MOSFET. For example, one end of the second capacitor 1051 may be connected to the respective sources of the first P-MOSFET 1011 and the second P-MOSFET 1021 . A gate of the third P-MOSFET 1041 may be connected to the other end of the capacitor 1051 . In the embodiment of FIG. 10G , sources of the first N-MOSFET 1010 and the second N-MOSFET 1020 may be connected to the drain of the third N-MOSFET 1040 . The second inductor 1030 may be connected to the source of the third N-MOSFET 1040 . Meanwhile, sources of the first N-MOSFET 1010 and the second N-MOSFET 1020 may be connected to one end of the first capacitor 1050 . A gate of the third N-MOSFET 1040 may be connected to the other end of the first capacitor 1050 . The drain of the third P-MOSFET 1041 may be connected to the source of each of the first P-MOSFET 1011 and the second P-MOSFET 1021 . The first inductor 1031 may be connected to the source of the third P-MOSFET 1041 . Meanwhile, one end of the second capacitor 1051 may be connected to sources of the first P-MOSFET 1011 and the second P-MOSFET 1021, respectively. A gate of the third P-MOSFET 1041 may be connected to the other end of the second capacitor 1051 . As the capacitor is additionally included, the peak current may be alleviated.

An instantaneous peak current can instantly increase the drain voltage of the MOSFET, but at this time, the gate voltage also increases, reducing the MOSFET's impedance. In this case, the size of the instantaneous peak current and voltage can be reduced by the transition phenomenon by the resistance or capacitor parasitic in the circuit, so that the harmonic current in the form of a spike transmitted to the ground or driving power input terminal of the PA driver, Voltage noise can be reduced.

A signal is output to an amplifier through the PA driver shown in FIGS. 10A to 10G , and the amplifier can amplify a signal from which noise has been removed through the PA driver.

10A to 10G show a PA driver for a differential signal, but are not limited thereto, and the PA driver may be implemented appropriately for a single-ended signal. For example, when single-ended signals are targeted, the second N-MOSFET 1020 and the second P-MOSFET 1021 in FIGS. 10A to 10G may be removed.

In addition, although CMOS transistors are shown in FIGS. 10A to 10G , this is only an example for the purpose of explanation, and it is possible to implement the same method through other types of transistors such as bipolar junction transistors (BJTs). is obvious to the technician of

11 illustrates waveforms of signals before and after noise removal through a PA driver according to various embodiments of the present invention.

11(a) shows a waveform of a signal before noise is removed through the PA driver. As shown in the waveform of the signal shown in (a) of FIG. 11, since the wireless power transmitter transmits relatively large power, relatively large voltage swings and current swings may occur in the wireless power transmitter. In particular, when the wireless power transmitter uses a class D or E amplifier that operates by switching, since the voltage signal transitions from 0V to VDD or from VDD to 0V in a square wave, a relatively large peak current is shown in FIG. 11 (a). It can occur like the waveform of the signal shown in.

11(b) shows a waveform of a signal before noise is removed through the PA driver. As shown in the waveform of the signal shown in (b) of FIG. 11, when harmonics with a high instantaneous peak current are generated in the wireless power transmitter, EMI radiation can be reduced by attenuating the inductor. In addition, when a MOS or BJT circuit is included in the wireless power transmitter, a capacitor is disposed between the gate-drain or base-collector of the current source circuit to enable feedback, so that the peak current of harmonics is It can be relaxed like the waveform of the signal shown in b).

12 is a diagram for explaining a method of detecting a positional change of a wireless power receiver in a wireless power transmitter according to various embodiments of the present disclosure.

According to various embodiments of the present disclosure, the wireless power transmitter 1200 may detect a positional change of the wireless power receiver. The wireless power transmitter 1200 may detect a change in resonance impedance due to a relative position change with the wireless power receiver. As such, the wireless power transmitter 1200 may detect a change in resonance impedance, and may detect a change in position of the wireless power receiver based on the detected change in resonance impedance.

For example, when the wireless power receiver is moved from the first position 1210 to the second position 1211, the wireless power transmitter 1200 detects a change in resonance impedance and based on the detected change in resonance impedance. Accordingly, it may be detected that the wireless power transmitter has moved from the first position 1210 to the second position 1211.

13A to 13C show signal waveforms according to comparative examples.

13A shows a first waveform 1312 and a second waveform 1313 for each of the first signal and the second signal constituting the differential signal amplified by the amplifier. The first waveform 1312 of the first signal may have a square wave shape, and the second waveform 1313 of the second signal may have a square wave shape. As described above, the first signal and the second signal may have a phase difference of 180 degrees, and accordingly, it can be seen that the first waveform 1312 and the second waveform 1313 are shown as having a phase difference of 180 degrees. there is.

Meanwhile, for example, when the resonance impedance of the wireless power transmitter changes due to the environment around the resonator or the environment around the antenna, such as a change in the position of the wireless power receiver, the phase difference between the first signal and the second signal is 180 degrees. may not be able to maintain As shown in FIG. 13B, it can be confirmed that the second waveform 1314 corresponding to the second signal has shifted to the right compared to FIG. 13A. Accordingly, it can be confirmed that the first waveform 1312 and the second waveform 1314 do not maintain a phase difference of 180 degrees. As the first waveform 1312 and the second waveform 1314 do not maintain a phase difference of 180 degrees, a portion of the first waveform 1312 and a portion of the second waveform 1314 overlap (1321, 1322, 1323) may occur. As portions 1321, 1322, and 1323 overlap a portion of the first waveform 1312 and a portion of the second waveform 1314, EMI may increase and overall wireless charging efficiency may decrease.

In addition, when the resonant impedance of the wireless power transmitter changes due to the environment around the resonator or the environment around the antenna, such as a position change of the wireless power receiver, the amplitudes of the first signal and the second signal may be different. As shown in FIG. 13C, it can be confirmed that the amplitude of the second waveform 1331 corresponding to the second signal is smaller than that of FIG. 13A. Accordingly, it can be confirmed that the amplitudes of the first waveform 1312 and the second waveform 1331 are different. The wireless charging efficiency of the wireless power transmitter changes according to the amplitudes of the first signal and the second signal, and as the amplitudes of the first waveform 1312 and the second waveform 1331 change, the overall wireless charging efficiency may decrease. can

14A and 14B are diagrams for explaining a method of notifying that a position of a wireless power receiver in a wireless power transmitter is out of a preset position according to various embodiments of the present disclosure.

As described with reference to FIG. 12 , the wireless power transmitter 1400 may detect a positional change of the wireless power receiver. Accordingly, the wireless power transmitter 1400 may provide a notification to the user when the location of the wireless power receiver deviates from the preset location 1411 to optimize wireless charging efficiency. For example, when the position of the wireless power receiver is moved from the preset position 1411 to the first position 1412, the resonance impedance of the wireless power transmitter 1400 changes, and accordingly, the wireless power transmitter 1400 ) of wireless charging efficiency may be reduced. Accordingly, when the location of the wireless power receiver deviate from the preset location 1411, the wireless power transmitter 1400 provides a notification to the user indicating that the location of the wireless power receiver deviated from the preset location 1411 so that the user can The location of the wireless power receiver may be induced to move to the preset location 141 .

As shown in FIG. 14A, when the position of the wireless power receiver is out of the preset position 1411, the wireless power transmitter 1400 provides wireless power to the user through the display unit 1401 included in the wireless power transmitter 1400, such as an LED lamp. A notification indicating that the location of the receiver deviated from the preset location 1411 may be provided. For example, the wireless power transmitter 1400 may provide a notification to the user by turning on the LED lamp 1401 in a specific color or turning the LED lamp 1401 off.

In addition, as shown in FIG. 14B, when the position of the wireless power receiver is out of the preset position 1411, the wireless power transmitter 1400 transmits a signal indicating that the wireless power receiver has moved out of the preset position 1411 to the wireless power receiver. can be sent to When receiving the signal, the wireless power receiver may provide a notification indicating that the location of the wireless power receiver has deviated from the preset location 1411 to the user through a display unit such as a display.

In addition, the wireless power transmitter 1400 may transmit the signal to the wireless power receiver and also provide a notification to the user through the display unit 1401 included in the wireless power transmitter 1400.

15 is a configuration diagram of a current sensing circuit of a differential structure according to various embodiments of the present disclosure.

Referring to FIG. 15 , the current sensing circuit may largely include a power amplifier 1500, a first current detection resistor 1530, a second current detection resistor 1535, and a load resistor 1505 for load detection. there is. The current sensing circuit of FIG. 15 places a current sensing resistor in series in a signal path for measuring the AC/RF current output from the power amplifier 1500 or delivered to the resonator, and the voltage across the current sensing resistor. A way to measure the difference between In particular, in a differential structure, two current detection resistors are equally arranged in positive and negative directions, and voltages at both ends of the current detection resistors, that is, in four places, are crossed and sampled. At this time, the cross method is configured so that the common mode is reduced and the effect of asymmetry is offset.

The power amplifier 1500 applies a first output voltage to one end of the load 1505 and applies a second output voltage opposite to the first output voltage to the other end of the load 1505. At this time, the second output voltage represents a polarity opposite to that of the first output voltage. The power amplifier 1500 according to various embodiments of the present disclosure may be a class D or E amplifier. Here, the load 1505 may be a load corresponding to an antenna or a resonator.

The load resistor 1505 may be denoted by 'R _L ', and may be implemented as two first resistors and a second resistor as shown in FIG. 4 to express asymmetry in terms of a differential circuit. At this time, the first resistance and the second resistance are different from each other by ΔR _L , and in this case, the first resistance is '0.5R _L + ΔR _L ', and the second resistance can be expressed as '0.5R _{L -} ΔR _L ' there is. The middle of the first resistor and the second resistor becomes the ground.

The first current detection resistor 1530 and the second current detection resistor 1535 may be respectively expressed as ' _RS '. The current sensing circuit is for obtaining the voltage 'V _RS ' across both ends of the first current sensing resistor 1530 . When such 'V _RS ' is obtained, it can be amplified in a circuit connected to the current sensing circuit and used to sense the size of the current. However, in the case of a current sensing circuit in which one current sensing resistor is disposed, a common mode problem may occur because a difference between voltages across the resistor is very large. Therefore, when the voltage swing of the signal to be sensed is very large, the current sensing circuit according to various embodiments of the present disclosure is disposed with two current sensing resistors so as not to be affected by problems caused by the common mode and asymmetry of the internal circuit.

These two current detection resistors 1530 and 1535 change as the load impedance changes when the voltage and current signals output from the power amplifier 1500 are applied to a load such as an antenna or a resonator, for example, the load 1505. The current signal (I _RF ) can be measured and used to control the operational amplifier.

First, the first current detection resistor 1530 is disposed between the first output of the power amplifier 1500 and the load 1505, and the second current detection resistor 1535 is the first output of the power amplifier 1500. It can be placed between output 2 and the load 1505.

The first voltage (V ₁ ) 1510 is the voltage applied to the front end of the first current detection resistor 1530, and the second voltage (V ₂ ) 1515 is the voltage of the first current detection resistor 1530. This is the voltage applied to the back end. The third voltage (V ₃ ) 1520 is the voltage applied to the front end of the second current detection resistor 1535, and the fourth voltage (V ₄ ) 1525 is the back end of the second current detection resistor 1535. is the voltage applied to

The current sensing circuit can obtain voltages input to the operational amplifier 1600 of FIG. 16 based on Equations 1 and 2 below.

In Equations 1 and 2, V _P and V _N are positive and negative voltages of the signal voltage across the load 1505, respectively. In various embodiments of the present invention, V _P is referred to as a first reference voltage, and V _N may be referred to as a second reference voltage. Also, in Equations 1 and 2, V _RS is a voltage applied to each of the first current detection resistor 1530 and the second current detection resistor 1535. This V _RS is the product of the current to be sensed (I _RF ) and the value of the resistance (R _S ), and is a very small voltage. That is, V _RS can be expressed as in Equation 3 below.

Meanwhile, according to Equation 1, the fifth voltage (V ₅ ) may be obtained by adding the first voltage (V ₁ ) (1510) and the fourth voltage (V ₄ ) (1525). Also, according to Equation 2, the sixth voltage (V ₆ ) may be obtained by adding the second voltage (V ₂ ) (1515) and the third voltage (V ₃ ) (1520).

If this is implemented as a circuit, it is as shown in FIG. 16 .

16 is a configuration diagram of an amplifier circuit connected to the current sensing circuit according to various embodiments of the present disclosure.

As shown in FIG. 16, the voltages (V _{1 ,} V ₂ , V ₃ , V ₄ ) across the first and second current detection resistors 1530 and 1535 of FIG. 15 respectively These may be added together in a cross form through a voltage divider and output in the form of a fifth voltage (V ₅ ) and a sixth voltage (V ₆ ). Here, the first voltage divider generates a first voltage (V ₁ ) applied to the front end of the first current detection resistor 1530 and a fourth voltage (V ₄ ) applied to the rear end of the second current detection resistor 1535. can play a role in integrating In addition, the second voltage divider generates a second voltage (V ₂ ) applied to the rear end of the first current detection resistor 1530 and a third voltage (V ₃ ) applied to the front end of the second current detection resistor 1535 can play a role in integrating The first voltage divider and the second voltage divider may be connected to a front end of the operational amplifier 1600 .

Accordingly, the fifth voltage (V ₅ ) and the sixth voltage (V ₆ ) are input to the operational amplifier 1600, and through the operational amplifier 1600, the fifth voltage (V ₅ ) and the sixth voltage (V ₆ ) difference between them can be obtained. The output voltage ( _VO ) obtained through the subtraction circuit using the operational amplifier 1600 may be expressed as in Equation 4 below. At this time, the operational amplifier 1600 serves to amplify the difference between the fifth voltage (V ₅ ) and the sixth voltage (V ₆ ) by a gain A.

In Equation 4, A represents a gain of the operational amplifier 1600 as a preset gain.

According to Equation 4, the output voltage ( _VO ) output from the operational amplifier 1600 is a voltage that is not affected by V _P and V _N , that is, is not affected by 'R _L ', which is the load 1505. can be output.

As described above, 2A * V _RS , which is an output voltage ( _VO ) that is not affected by a change in 'R _L ', which is the load 1505 according to various embodiments of the present disclosure, can be obtained.

In addition, since the above equations can be applied even when the magnitudes of V _P and V _N are different from each other compared to the asymmetry of the differential structure, sensing performance due to the asymmetry can be improved. _In addition, since the common mode problem is also expressed as V _{P - V N} when viewed from the input of the operational amplifier 1600, if the asymmetry is not severe, that is, the size difference between V _P and V _N is within a predetermined range. If it falls within the range, a magnitude significantly smaller than the absolute magnitude of V _P and V _N , which are the voltage swings of the load, is applied to the common mode, and the problem of not seeing the desired signal due to the output magnitude of the common mode signal can be solved.

On the other hand, the output voltage ( _VO ) output from the operational amplifier 1600 needs to be converted from an alternating current signal to a constant DC voltage in order to be input to the controller and communication units 312 and 313. To this end, as shown in FIG. 17 , a rectifier circuit unit 1700 for leveling DC may be implemented.

Accordingly, the control unit and the communication unit of the wireless power transmitter may generate a control signal based on the output voltage (V _O ) provided from the sensing circuit. Accordingly, the signal generating unit may generate power based on the control signal provided from the control unit.

As described above, the sensing circuit according to various embodiments of the present invention may be configured including the FIGS. 15 and 16, and the output voltage ( _VO ) of FIG. 17 may be provided to the control unit and the communication unit. A rectifier circuit unit 1700 may be further included.

If the sensing circuit is implemented to include the configuration of FIGS. 15 and 16, the sensing circuit supplies a first output voltage to one end of the load, and the second output voltage, which is opposite to the first output voltage, is A first amplifier supplied to the other end of the load, a first current detection resistor disposed between the first output of the first amplifier and the load, and disposed between the second output of the first amplifier and the load A fifth voltage obtained by summing a second current sensing resistor, a first voltage applied to a front end of the first current sensing resistor and a fourth voltage applied to a rear end of the second current sensing resistor, and a voltage applied to a rear end of the first current sensing resistor A second amplifier for outputting an output voltage proportional to a difference between the fifth voltage and the sixth voltage after obtaining a sixth voltage obtained by summing the second voltage applied and the third voltage applied to the front end of the second current detection resistor. can include

Each of the components described in this document may be composed of one or more components, and the name of the corresponding component may vary depending on the type of electronic device. In various embodiments, an electronic device may include at least one of the components described in this document, and some components may be omitted or additional components may be further included. In addition, some of the components of the electronic device according to various embodiments are combined to form a single entity, so that the functions of the corresponding components before being combined can be performed the same.

The term "module" used in this document may refer to a unit including one or a combination of two or more of, for example, hardware, software, or firmware. “Module” may be used interchangeably with terms such as, for example, unit, logic, logical block, component, or circuit. A “module” may be a minimum unit or part of an integrally formed part. A “module” may be a minimal unit or part thereof that performs one or more functions. A “module” may be implemented mechanically or electronically. For example, a "module" is any known or future developed application-specific integrated circuit (ASIC) chip, field-programmable gate arrays (FPGAs), or programmable-logic device that performs certain operations. may contain at least one.

At least some of the devices (eg, modules or functions thereof) or methods (eg, operations) according to various embodiments may be stored on computer-readable storage media in the form of, for example, program modules. It can be implemented as a command stored in . When the command is executed by a processor, the one or more processors may perform a function corresponding to the command. A computer-readable storage medium may be, for example, a memory.

Computer-readable recording media include hard disks, floppy disks, magnetic media (eg magnetic tape), optical media (eg CD-ROM (compact disc read only memory), DVD ( digital versatile disc), magneto-optical media (such as floptical disk), hardware devices (such as read only memory (ROM), random access memory (RAM), or flash memory, etc.) ), etc. In addition, the program command may include not only machine code generated by a compiler, but also high-level language code that can be executed by a computer using an interpreter, etc. The above-described hardware device may include various It may be configured to act as one or more software modules to perform the operations of an embodiment, and vice versa.

A module or program module according to various embodiments may include at least one or more of the aforementioned components, some may be omitted, or additional other components may be included. Operations performed by modules, program modules, or other components according to various embodiments may be executed in a sequential, parallel, repetitive, or heuristic manner. Also, some actions may be performed in a different order, omitted, or other actions may be added.

According to various embodiments, in a storage medium storing instructions, the instructions may be configured to cause the at least one processor to perform at least one operation when executed by at least one processor.

In addition, the embodiments disclosed in this document are presented for explanation and understanding of the disclosed technical content, and do not limit the scope of the technology described in this document. Therefore, the scope of this document should be construed as including all changes or various other embodiments based on the technical idea of this document.

Claims (20)

◈Claim 1 was abandoned when the registration fee was paid.◈ A wireless power transmitter for wirelessly charging a wireless power receiver,
a signal generating unit generating a differential signal;
a modulator configured to adjust a phase of the generated differential signal through a plurality of inverters based on a control signal for controlling phase adjustment of the differential signal;
an amplifier for amplifying the adjusted differential signal with a preset gain;
a resonance unit transmitting the amplified differential signal to the wireless power receiver;
a sensing unit sensing voltage and current of the amplified differential signal; and
A control unit generating the control signal for controlling the phase difference between the signals included in the amplified differential signal to be a preset phase difference based on the sensed voltage and current and outputting the generated control signal to the modulation unit;
The modulator is configured by connecting at least one first inverter of the plurality of inverters in series, and adjusts a phase of a first signal included in the generated differential signal through the at least one first inverter. A phase control unit and at least one second inverter among the plurality of inverters are connected in series, and the phase of the second signal included in the generated differential signal is adjusted through the at least one second inverter. A wireless power transmitter including a two-phase control unit.
delete ◈Claim 3 was abandoned when the registration fee was paid.◈ According to claim 1,
The first phase controller,
A first multiplexer outputting an output of a third inverter determined based on the control signal among the at least one first inverter.
including,
The second phase controller,
A second multiplexer outputting an output of a fourth inverter determined based on the control signal among the at least one second inverter.
A wireless power transmitter comprising a. ◈Claim 4 was abandoned when the registration fee was paid.◈ According to claim 3,
The first phase controller,
Further comprising a first capacitor disposed between an output terminal of one of the at least one first inverter and a ground terminal;
The second phase controller,
The wireless power transmitter further comprising a second capacitor disposed between an output terminal of one of the at least one second inverter and a ground terminal. ◈Claim 5 was abandoned when the registration fee was paid.◈ According to claim 4,
The first capacitor and the second capacitor are variable capacitors,
The capacitance of the first capacitor and the second capacitor is adjusted based on the control signal, wireless power transmitter. ◈Claim 6 was abandoned when the registration fee was paid.◈ According to claim 1,
The control unit,
The wireless power transmitter for generating the control signal for controlling the amplitude of each of the first signal and the second signal included in the amplified differential signal to be a preset amplitude. ◈Claim 7 was abandoned when the registration fee was paid.◈ According to claim 6,
The modulator,
an amplitude controller configured to adjust amplitudes of the first signal and the second signal included in the differential signal using the driving voltage adjusted based on the control signal; and
A voltage regulator adjusting the driving voltage supplied to the amplitude controller based on the control signal.
A wireless power transmitter further comprising a. ◈Claim 8 was abandoned when the registration fee was paid.◈ According to claim 7,
The amplitude control unit,
Adjust the amplitude of the phase-adjusted first signal output from the first phase control unit using the adjusted driving voltage, and output the phase-adjusted first signal to the first input terminal of the amplifier. do,
Adjusting the amplitude of the phase-adjusted second signal output from the second phase control unit based on the control signal, and outputting the phase and amplitude-adjusted second signal to a second input terminal of the amplifier, wireless power transmitter. ◈Claim 9 was abandoned when the registration fee was paid.◈ According to claim 7,
The amplitude control unit,
Adjusting the amplitude of the first signal based on the control signal, and outputting the first signal with the adjusted amplitude to the first phase control unit;
A wireless power transmitter for adjusting an amplitude of the second signal based on the control signal and outputting the second signal having the adjusted amplitude to the second phase control unit. A wireless power transmitter for wirelessly charging a wireless power receiver,
A signal generator for generating a single-ended signal; In a wireless power transmitter for wirelessly charging a wireless power receiver,
a signal generating unit generating a single-ended signal;
a modulator configured to adjust a phase of the generated single-ended signal through at least one inverter based on a control signal for controlling phase adjustment of the single-ended signal;
an amplifier for amplifying the adjusted single-ended signal with a preset gain;
a resonance unit transmitting the amplified single-ended signal to the wireless power receiver;
a sensing unit sensing voltage and current of the amplified single-ended signal; and
a control unit generating the control signal for controlling a phase of the amplified single-ended signal to be a predetermined phase based on the sensed voltage and current, and outputting the generated control signal to the modulation unit;
Wherein the control unit generates the control signal for controlling the amplitude of the amplified single-ended signal to be a preset amplitude. According to claim 10,
The modulator,
The at least one inverter is connected in series, and the phase controller adjusts the phase of the generated single-ended signal through the at least one inverter.
A wireless power transmitter comprising a. According to claim 11,
The phase control unit,
A multiplexer for outputting an output of a first inverter determined based on the control signal among the at least one inverter
A wireless power transmitter comprising a. According to claim 12,
The phase control unit,
The wireless power transmitter further comprising a capacitor disposed between an output terminal of one of the at least one inverter and a ground terminal. According to claim 13,
The capacitor is a variable capacitor,
The capacitance of the capacitor is adjusted based on the control signal, wireless power transmitter. delete According to claim 10,
The modulator,
an amplitude control unit adjusting an amplitude of the single-ended signal call using a driving voltage adjusted based on the control signal; and
A voltage regulator adjusting the driving voltage supplied to the amplitude controller based on the control signal.
A wireless power transmitter further comprising a. According to claim 16,
The amplitude control unit,
Adjusting the amplitude of the phase-adjusted single-ended signal output from the phase controller using the adjusted driving voltage, and outputting the phase- and amplitude-adjusted single-ended signal to a first input terminal of the amplifier. power transmitter. According to claim 17,
The amplitude control unit,
A wireless power transmitter configured to adjust an amplitude of the single-ended signal based on the control signal and output the single-ended signal having the adjusted amplitude to the phase control unit. In an integrated circuit (IC) for controlling a phase of a differential signal transmitted to a wireless power receiver for wireless charging,
At least one first inverter is configured by being connected in series, and a first signal included in a differential signal supplied to the IC through the at least one first inverter based on a control signal for controlling phase adjustment of the differential signal A first phase controller for adjusting the phase of; and
A second phase controller configured by connecting at least one second inverter in series and adjusting a phase of a second signal included in the differential signal through the at least one second inverter based on the control signal
IC containing. According to claim 19,
an amplitude controller configured to adjust amplitudes of the first signal and the second signal included in the differential signal using the driving voltage adjusted based on the control signal; and
A voltage regulator adjusting the driving voltage supplied to the amplitude controller based on the control signal.
IC further comprising.

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