Electronic device, electronic device control method and program

Abstract

To provide an electronic apparatus, a control method for an electronic apparatus, and a program, for suppressing repetition of a display indicating that a power receiving device is being charged and a stop of the display indicating that the power receiving device is being charged.SOLUTION: An electronic apparatus 102 includes: a power transmitting device 100 for transmitting power wirelessly to a power receiving device; and a control unit 301 for performing control to effect a display indicating that the power receiving device is being charged when power transmission means is transmitting power and to stop the display indicating that the power receiving device is being charged when the power transmission means has stopped transmitting power. The power transmitting device transitions from a normal mode to a power-saving mode in which a period from when the power transmitting means stops transmitting power until the power transmitting means transmits power for object detection is longer than in the normal mode, on the basis of the information on the power receiving device.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present disclosure relates to an electronic device, a control method for an electronic device, and a program. [Background technology]

[0002] Technical development of wireless power transmission systems is widespread. Patent Document 1 discloses a power transmitting device and a power receiving device that comply with the standard (WPC standard) established by the Wireless Power Consortium (WPC), a standardization organization for wireless charging standards. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2015-56959 Summary of the Invention [Problem to be solved by the invention]

[0004] Even after charging is complete, a power transmitting device needs to detect whether a new power receiving device has been placed on the device. Therefore, after completing charging and stopping power transmission, the power transmitting device immediately transmits a signal for object detection, followed by a signal for detecting the power receiving device. When the power transmitting device transmits the latter signal, charging is completed, and the charging unit of the power receiving device that remains on the power transmitting device starts up, and power transmission from the power transmitting device to the power receiving device resumes. Accordingly, a charging message may be displayed on the device incorporating the power transmitting device. Thereafter, the power transmitting device detects full charge, stops power transmission again, and stops the charging message. Because this operation may be repeated, there is a problem in that the charging message is repeatedly displayed and hidden, which is annoying to the user.

[0005] The present disclosure aims to prevent a display indicating that a power receiving device is being charged from being repeatedly displayed and stopped. [Means for solving the problem]

[0006] The electronic device includes a power transmitting means for transmitting power wirelessly to a power receiving device, and a control means for controlling the power transmitting means to display a message indicating that the power receiving device is being charged when the power transmitting means is transmitting power, and to stop displaying a message indicating that the power receiving device is being charged when the power transmitting means has stopped transmitting power, and the power transmitting means controls the power receiving device to perform a process based on information about the power receiving device. If the remaining battery charge of the power receiving device is greater than a first threshold value, A transition from a normal mode to a power saving mode in which the period from when the power transmitting means stops transmitting power until when the power transmitting means starts transmitting power for object detection is longer than in the normal mode. In the power saving mode, when the remaining battery capacity of the power receiving device based on the information of the power receiving device becomes smaller than a second threshold, the mode is shifted to the normal mode, and the second threshold is smaller than the first threshold. . [Effects of the Invention]

[0007] According to the present disclosure, it is possible to prevent the display indicating that the power receiving device is being charged from being repeatedly switched between displaying the indication that the power receiving device is being charged and stopping the display indicating that the power receiving device is being charged. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a block diagram illustrating an example of the configuration of an electronic device. [Figure 2] FIG. 2 is a block diagram illustrating a configuration example of a power transmission device. [Figure 3] FIG. 2 is a block diagram illustrating a configuration example of a power receiving device. [Figure 4] FIG. 2 is a sequence diagram of a power transmitting device and a power receiving device. [Figure 5] FIG. 2 is a sequence diagram of an electronic device, a power transmitting device, and a power receiving device. [Figure 6] 1A and 1B are diagrams illustrating examples of displays on a display unit of an electronic device. [Figure 7] 10 is a flowchart illustrating an example of processing performed by a power transmitting device. [Figure 8] FIG. 2 is a sequence diagram of an electronic device, a power transmitting device, and a power receiving device. [Figure 9] 10 is a flowchart illustrating an example of processing performed by a power transmitting device. DETAILED DESCRIPTION OF THE INVENTION

[0009] (First embodiment) Hereinafter, the embodiments will be described in detail with reference to the drawings. Although the embodiments describe a plurality of features, not all of these features are necessarily essential, and the plurality of features may be combined arbitrarily. Furthermore, in the drawings, the same reference numerals are used to designate the same or similar components.

[0010] [Electronic device configuration] FIG. 1 is a diagram showing an example of the configuration of an electronic device 102 according to the first embodiment. The electronic device 102 is a wireless power transmission system, and in one example, includes a power receiving device 101 and a power transmitting device 100. The power transmitting device 100 transmits power wirelessly to the power receiving device 101. The power receiving device 101 receives power from the power transmitting device 100 and charges an internal battery. The electronic device 102 is an electronic device that incorporates at least the power transmitting device 100. Examples of the electronic device 102 include an automobile and a camera. The electronic device 102 may also be a smartphone, a tablet personal computer (PC), a laptop, a robot, a medical device, a printer, a headset, or other devices.

[0011] [Device configuration] FIG. 2 is a diagram showing an example of the configuration of the power receiving device 101 of FIG. 1. The power receiving device 101 complies with the WPC standard and includes a control unit 200, a power receiving coil 201, a rectifying unit 202, a voltage control unit 203, a communication unit 204, a charging unit 205, and a battery 206. The control unit 200 controls the entire power receiving device 101. An example of the control unit 200 is a CPU. The power receiving coil 201 receives power from a power transmitting coil 304 (FIG. 3) of the power transmitting device 100. The rectifying unit 202 converts the AC voltage and AC current received from the power transmitting coil 304 via the power receiving coil 201 into a DC voltage and DC current. The voltage control unit 203 converts the level of the DC voltage input from the rectifying unit 202 to a DC voltage level at which the control unit 200, the charging unit 205, and the like operate. Charging unit 205 charges battery 206 with the DC voltage converted by voltage control unit 203. Communication unit 204 performs control communication for wireless charging based on the WPC standard with communication unit 305 (FIG. 3) of power transmitting device 100. This control communication is realized by load modulation of the AC voltage and AC current received by power receiving coil 201.

[0012] Furthermore, the power receiving device 101 may be built into another device different from the electronic device 102 (a camera, a smartphone, a tablet PC, a laptop, an automobile, a robot, a medical device, or a printer).

[0013] FIG. 3 is a diagram showing an example of the configuration of the power transmitting device 100 in FIG. 1. The electronic device 102 includes the power transmitting device 100, a control unit 301, and a display unit 307. The power transmitting device 100 complies with the WPC standard and includes a control unit 300, a power supply unit 302, a power transmitting unit 303, a power transmitting coil 304, a communication unit 305, and a memory 306. The control unit 300 controls the entire power transmitting device 100. An example of the control unit 300 is a CPU. The power supply unit 302 supplies power to each functional block of the power transmitting device 100. The power supply unit 302 is, for example, a commercial power supply or a battery. The battery stores power supplied from the commercial power supply.

[0014] The power transmitting unit 303 converts the DC or AC power input from the power supply unit 302 into AC power in a frequency band used for wireless power transmission, and inputs the AC power to the power transmitting coil 304 to generate electromagnetic waves for receiving power at the power receiving device 101. For example, the power transmitting unit 303 converts the DC voltage supplied by the power supply unit 302 into an AC voltage using a switching circuit with a half-bridge or full-bridge configuration using field effect transistors (FETs). In this case, the power transmitting unit 303 includes a gate driver that controls the on / off of the FETs.

[0015] Furthermore, power transmitting unit 303 controls the intensity of the electromagnetic waves to be output by adjusting the voltage (transmission voltage), current (transmission current), or both, or frequency input to power transmitting coil 304. When power transmitting unit 303 increases the transmission voltage or transmission current, the intensity of the electromagnetic waves increases, and when power transmitting unit 303 decreases the transmission voltage or transmission current, the intensity of the electromagnetic waves decreases. Furthermore, control unit 300 controls power transmitting unit 303 so that power transmission from power transmitting coil 304 starts or stops, thereby controlling the output of AC power from power transmitting unit 303. Furthermore, power transmitting unit 303 is capable of supplying enough power to output 15 watts (W) to charging unit 205 of power receiving device 101, which complies with the WPC standard.

[0016] The communication unit 305 communicates with the power receiving device 101 via the power transmitting coil 304 for power transmission control based on the WPC standard. The communication unit 305 performs frequency shift keying (FSK) on the AC voltage and AC current output from the power transmitting unit 303 and transmits information to the power receiving device 101 to perform communication. The communication unit 305 also demodulates the AC voltage and AC current modulated by the communication unit 204 of the power receiving device 101 to acquire information transmitted by the power receiving device 101. That is, the communication unit 305 performs communication by superimposing a signal on electromagnetic waves transmitted by the power transmitting unit 303. The communication unit 305 may also communicate with the power receiving device 101 using a standard other than the WPC standard that uses a coil (or antenna) different from the power transmitting coil 304, or may communicate with the power receiving device 101 by selectively using multiple communication methods.

[0017] The memory 306 can store the control program as well as the states of the power transmitting device 100 and the power receiving device 101. For example, the state of the power transmitting device 100 is acquired by the control unit 300. The state of the power receiving device 101 is acquired by the control unit 200 of the power receiving device 101. The control unit 300 receives the state of the power receiving device 101 from the power receiving device 101 via the communication unit 305.

[0018] The display unit 307 displays and notifies the user of the state of the power transmitting device 100 itself or the state of the electronic device 102 including the power transmitting device 100 and the power receiving device 101 as shown in Fig. 1. In this embodiment, the display unit 307 will be described using a display as an example, but other configurations may be used as long as they notify the user of the above states, and may be a speaker that outputs audio, a vibration generating circuit, or an LED.

[0019] The control unit 301 is a control unit implemented in the electronic device 102 incorporating the power transmitting device 100, and controls the display unit 307. The control unit 301 also has a wired or wireless communication path between itself and the control unit 300 of the power transmitting device 100, and receives information relating to the power transmitting device 100 and the power receiving device 101.

[0020] 4 is a sequence diagram of the power transmitting device 100 and the power receiving device 101 according to this embodiment. First, the flow of a control method for the power transmitting device 100 and the power receiving device 101 that complies with the WPC standard v1.2.3 will be described using the sequence diagram in FIG.

[0021] In step F400, the power transmitting device 100 transmits an Analog Ping to detect an object present near the power transmitting coil 304. The Analog Ping is a pulsed power for detecting an object. The Analog Ping is such a small power that even if the power receiving device 101 receives the Analog Ping, it cannot activate the control unit 200 of the power receiving device 101. The power transmitting device 100 detects an object based on a shift in the resonant frequency of the voltage value inside the power transmitting coil 304 or a change in the voltage value or current value of the power transmitting coil 304, which is caused by an object present near the power transmitting coil 304.

[0022] In step F401, when the power transmitting device 100 detects an object by Analog Ping, it measures the Q-factor of the power transmitting coil 304 by Q-factor measurement. In step F402, following the Q-factor measurement, the power transmitting device 100 starts transmitting Digital Ping. Digital Ping is power for starting the control unit 200 of the power receiving device 101, and is greater than Analog Ping. Digital Ping is transmitted continuously thereafter. That is, the power transmitting device 100 continues to transmit power equal to or greater than Digital Ping from the time it starts transmitting Digital Ping (step F402) until it receives an EPT packet (step F422) from the power receiving device 101, which will be described later.

[0023] In step F403, when the power receiving apparatus 101 receives the Digital Ping and starts up, the power receiving apparatus 101 transmits to the power transmitting apparatus 100 a Signal Strength packet that stores the voltage value of the received Digital Ping.

[0024] Next, in step F404, the power receiving device 101 transmits an ID including version information of the WPC standard to which the power receiving device 101 conforms and device identification information to the power transmitting device 100. In step F405, the power receiving device 101 transmits to the power transmitting device 100 a Configuration packet that stores information including the maximum value of the power to be supplied to the load (charging unit 205).

[0025] In step F406, the power transmitting apparatus 100 determines from the ID and the Configuration packet that the power receiving apparatus 101 supports the extended protocol (including Negotiation, which will be described later) of the WPC standard v1.2 or later. Then, the power transmitting apparatus 100 responds to the power receiving apparatus 101 with an ACK for the Configuration packet.

[0026] In step F407, upon receiving the ACK, the power receiving apparatus 101 transitions to a negotiation phase in which negotiations on power to be transmitted and received are performed. First, the power receiving apparatus 101 transmits an FOD status to the power transmitting apparatus 100. In this embodiment, the FOD status is expressed as FOD(Q1).

[0027] In step F408, the power transmitting device 100 performs foreign object detection based on the Q value stored in the FOD(Q1) and the first foreign object detection method using the Q value measured in the above-mentioned Q value measurement, and transmits an ACK to the power receiving device 101 indicating that it has determined that there is a high possibility that no foreign object is present.

[0028] In step F409, upon receiving the ACK, the power receiving apparatus 101 negotiates Guaranteed Power, which is the maximum value of power that the power receiving apparatus 101 requests to receive. Guaranteed Power is the load power of the power receiving apparatus 101 (power consumed by the load) and indicates what has been agreed upon between the power transmitting apparatus 100 and the power receiving apparatus 101. Specifically, the power receiving apparatus 101 transmits to the power transmitting apparatus 100 a packet that stores the value of the Guaranteed Power requested by the power receiving apparatus 101, which is included in a Specific Request defined in the WPC standard. In this embodiment, this packet is expressed as SRQ(GP).

[0029] In step F410, the power transmitting device 100 responds to the power receiving device 101 with the SRQ(GP) packet, taking into consideration its own power transmission capability, etc. Specifically, the power transmitting device 100 determines that the Guaranteed Power is acceptable, and transmits an ACK indicating that the request has been accepted to the power receiving device 101. In this embodiment, it is assumed that the power receiving device 101 has requested 15 watts as Guaranteed Power in the SRQ(GP).

[0030] In step F411, when the negotiation of a plurality of parameters including Guaranteed Power is completed, the power receiving apparatus 101 transmits an SRQ (EN) of Specific Requests requesting the end of negotiation to the power transmitting apparatus 100. This end of negotiation is End Negotiation.

[0031] In step F412, the power transmitting apparatus 100 transmits an ACK in response to the SRQ(EN) to the power receiving apparatus 101. Then, the power transmitting apparatus 100 ends the negotiation and transitions to the power transfer phase in which the power transmitting apparatus 100 transmits and receives power determined by the guaranteed power.

[0032] Next, the power transmitting device 100 and the power receiving device 101 perform a second foreign object detection based on the power loss calculated from the transmitted power and the received power. In this embodiment, a Received Power Packet (mode 1) packet is represented as RP1, and a Received Power Packet (mode 2) packet is represented as RP2.

[0033] In step F413, the power receiving apparatus 101 transmits RP1 to the power transmitting apparatus 100. The power transmitting apparatus 100 receives RP1 from the power receiving apparatus 101.

[0034] In step F414, the power transmitting apparatus 100 transmits to the power receiving apparatus 101 an ACK indicating that the received power value stored in RP1 and the current transmitted power value of the power transmitting apparatus 100 are accepted as calibration data points.

[0035] In step F415, the power receiving device 101 transmits a Control Error (hereinafter referred to as CE) to the power transmitting device 100, requesting the power transmitting device 100 to increase or decrease the receiving voltage (receiving current or receiving power). CE stores a sign and a numerical value, where a positive sign indicates a request to increase power, a negative sign indicates a request to decrease power, and a zero numerical value indicates a request to maintain power. For example, the power receiving device 101 transmits CE(+), which indicates an increase in power, to the power transmitting device 100.

[0036] In step F416, upon receiving CE(+), the power transmitting device 100 changes the setting value of the power transmitting unit 303 that supplies the received power to the load, thereby increasing the transmission power.

[0037] In step F417, when the received power increases in response to CE(+), the power receiving apparatus 101 supplies the received power to the load and transmits RP2 to the power transmitting apparatus 100.

[0038] In step F418, the power transmitting apparatus 100 transmits an ACK in response to RP2 to the power receiving apparatus 101. The above is the description of the calibration process. From now on, the power transmitting apparatus 100 performs foreign object detection based on the second foreign object detection method.

[0039] At this point, the power transmitting apparatus 100 and the power receiving apparatus 101 have transitioned to the power transfer phase. The power transmitting apparatus 100 transmits the power that the power receiving apparatus 101 can receive, up to the maximum of 15 watts negotiated in the negotiation phase.

[0040] In step F419, the power receiving apparatus 101 transmits a CE indicating an increase or decrease in received power to the power transmitting apparatus 100. For example, the power receiving apparatus 101 transmits a CE(+) to the power transmitting apparatus 100 indicating that the power should be increased.

[0041] In step F420, the power transmitting device 100 transmits a Received Power Packet (mode 0) storing the current received power value to the power receiving device 101. In this embodiment, the Received Power Packet (mode 0) is represented as RP0. The power transmitting device 100 periodically transmits the CE in step F419 and the RP0 in step F420 to the power receiving device 101.

[0042] In step F421, upon receiving RP0 from the power receiving device, the power transmitting device 100 performs foreign object detection based on a second foreign object detection method (power loss method) based on the power loss calculated from the transmitted power and the received power. The power transmitting device 100 transmits an ACK to the power receiving device 101 indicating that it has determined that there is a high possibility that no foreign object is present as a result of the foreign object detection.

[0043] In step F422, when the charging is completed, the power receiving apparatus 101 transmits an End Power Transfer (EPT) packet to the power transmitting apparatus 100, requesting that the power transmitting apparatus 100 stop transmitting power.

[0044] When the power transmitting device 100 receives the EPT packet, it stops power transmission, returns to step F400 already described, and repeats the same operation. The above is the flow of the control method for the power transmitting device 100 and the power receiving device 101 that complies with WPC standard v1.2.3.

[0045] [Problem of this embodiment] Fig. 5 is a sequence diagram showing a control method for the electronic device 102, the power transmitting device 100, and the power receiving device 101. The problem of this embodiment will be described based on Fig. 5. Note that the same reference numerals are assigned to steps already described in Fig. 4, and the description thereof may be omitted.

[0046] In step F400, the power transmitting device 100 transmits an Analog Ping to the power receiving device 101. In step F423, the power transmitting device 100 and the power receiving device 101 perform the processes of steps F401 to F416 in Fig. 4 already described, transition to the Power Transfer phase, and start power transmission.

[0047] In step F424, the power receiving device 101 transmits a Charge Status Packet indicating the remaining battery charge of the battery 206 to the power transmitting device 100. The Charge Status Packet is expressed as a CSP in this embodiment. For example, the power receiving device 101 transmits a CPS (80%) to the power transmitting device 100. The CPS (80%) is a CSP including information that the remaining battery charge of the battery 206 is 80%.

[0048] In step F425, the power transmitting device 100 notifies the control unit 301 of the electronic device 102 that the remaining battery charge of the battery 206 is 80%. In step F428, the control unit 301 of the electronic device 102 displays the remaining battery charge of the battery 206 on the display unit 307 based on the notification in step F425.

[0049] In step F426, the power transmitting device 100 notifies the control unit 301 of the electronic device 102 that power is being transmitted to the power receiving device 101 (that is, the battery 206 is being charged). In step F431, based on the notification of step F426, the control unit 301 of the electronic device 102 causes the display unit 307 to display a message indicating that the battery 206 is being charged.

[0050] 6(a) to 6(c), examples of display on the display unit 307 will be described. The display unit 307 displays a battery icon 600 and a remaining battery capacity 601. The remaining battery capacity 601 next to the battery icon 600 indicates the remaining battery capacity of the battery 206 of the power receiving device 101. The display unit 307 can also display a charging icon 602. The charging icon 602 indicates that the battery 206 is currently charging.

[0051] 6(a), the remaining battery capacity 601 of the battery 206 is 100%, and the battery 206 is not charging. Also, according to the display in FIG. 6(b), the remaining battery capacity 601 of the battery 206 is 80%, and the battery 206 is charging.

[0052] Returning to the description of Fig. 5, in steps F424 and F427, the power receiving device 101 periodically transmits a CSP to the power transmitting device 100. Based on the received CPS, the power transmitting device 100 notifies the control unit 301 of the electronic device 102 of the remaining battery capacity of the battery 206. The electronic device 102 displays the notified remaining battery capacity on the display unit 307 as a remaining battery capacity 601.

[0053] In step F428, the control unit 301 of the electronic device 102 displays on the display unit 307, as shown in Fig. 6(b), that the remaining battery capacity 601 of the battery 206 is 80%. In step F431, the control unit 301 of the electronic device 102 displays on the display unit 307, as shown in Fig. 6(b), a charging icon 602 indicating that the battery 206 is being charged.

[0054] In step F427, the power receiving device 101 transmits a CPS (100%) to the power transmitting device 100. The power transmitting device 100 notifies the control unit 301 of the electronic device 102 that the remaining battery charge of the battery 206 is 100%. Based on the notification, the control unit 301 of the electronic device 102 displays a remaining battery charge 601 of the battery 206 and a charging icon 602 on the display unit 307, as shown in FIG. 6(c). According to the display in FIG. 6(c), the remaining battery charge 601 of the battery 206 is 100%, and the battery 206 is currently charging.

[0055] In step F422, the power receiving device 101 transmits an EPT packet to the power transmitting device 100 requesting that power transmission be stopped, because the remaining battery charge of the battery 206 is 100% and there is no longer any need to charge the battery 206. Upon receiving the EPT packet, the power transmitting device 100 stops transmitting power to the power receiving device 101. In step F429, the power transmitting device 100 notifies the control unit 301 of the electronic device 102 that power transmission has been stopped as a result of receiving the EPT packet.

[0056] 6(a), the control unit 301 of the electronic device 102 displays on the display unit 307 that the remaining battery capacity 601 of the battery 206 is 100% and that the battery 206 is not currently charging. The control unit 301 stops displaying the charging icon 602, thereby displaying that the battery 206 is not currently charging.

[0057] Immediately after step F422, in step F400, the power transmitting device 100 transmits the next Analog Ping to the power receiving device 101. In step F423, the power transmitting device 100 and the power receiving device 101 perform the processes of steps F401 to F416 in Fig. 4 already described, transition to the Power Transfer phase, and start power transmission. The remaining battery capacity of the battery 206 is 100% because very little time has passed since it reached 100% as described above.

[0058] In step F427, the power receiving device 101 transmits to the power transmitting device 100 a CSP (100%) including information that the remaining battery capacity of the battery 206 is 100%. In step F425, the power transmitting device 100 notifies the control unit 301 of the electronic device 102 that the remaining battery capacity of the battery 206 is 100%. In step F428, the control unit 301 of the electronic device 102 displays on the display unit 307, as shown in FIG. 6(c), that the remaining battery capacity 601 of the battery 206 is 100%.

[0059] In step F426, the power transmitting device 100 notifies the control unit 301 of the electronic device 102 that power is being transmitted to the power receiving device 101 (i.e., the battery 206 is being charged). In step F431, based on the notification of step F426, the control unit 301 of the electronic device 102 displays a charging icon 602 indicating that the battery 206 is being charged on the display unit 307, as shown in FIG. 6(c).

[0060] In step F422, the power receiving device 101 transmits an EPT packet to the power transmitting device 100 requesting that power transmission be stopped because the remaining battery charge of the battery 206 is 100% and charging is not necessary. Upon receiving the EPT packet, the power transmitting device 100 stops power transmission to the power receiving device 101.

[0061] In step F429, the power transmitting device 100 notifies the control unit 301 of the electronic device 102 that power transmission has been stopped due to the reception of the EPT packet. In step F430, the control unit 301 of the electronic device 102 displays on the display unit 307, as shown in Fig. 6(a), that the remaining battery capacity 601 of the battery 206 is 100% and that the battery 206 is not charging. The control unit 301 stops displaying the charging icon 602 to display that the battery 206 is not charging.

[0062] Immediately after step F422, in step F400, the power transmitting device 100 transmits the next Analog Ping to the power receiving device 101. Thereafter, the electronic device 102, the power transmitting device 100, and the power receiving device 101 repeat the above process. Then, as described above, the display unit 307 repeatedly displays the display of FIG. 6(c) indicating that charging is in progress in step F431 and the display of FIG. 6(a) indicating that charging is not in progress in step F430, at short intervals. This is bothersome for the user and poses a problem in terms of the usability of the electronic device 102.

[0063] [Processing of the electronic device 102 according to this embodiment] The processing of the electronic device 102 according to this embodiment, which solves the above-mentioned problems, will be described with reference to Fig. 7 and Fig. 8. Fig. 7 is a flowchart illustrating the power saving mode processing of the power transmitting device 100 according to this embodiment.

[0064] In step S700, the control unit 300 of the power transmitting device 100 transmits an Analog Ping and detects whether an object is placed on the power transmitting coil 304 of the power transmitting device 100. If the control unit 300 detects that an object is placed, it transmits a Digital Ping and detects whether the object is a power receiving device 101 that complies with the WPC standard. If the object is a power receiving device 101 that complies with the WPC standard, the control unit 300 proceeds to step S701. If the object is not a power receiving device 101 that complies with the WPC standard or if no object is placed, the control unit 300 ends the processing of the flowchart in FIG. 7.

[0065] In step S701, the control unit 300 of the power transmitting device 100 starts transmitting power to the power receiving device 101. In step S702, the power receiving device 101 transmits information about the remaining battery capacity of the battery 206 to the power transmitting device 100. The control unit 300 of the power transmitting device 100 receives the information about the remaining battery capacity of the battery 206 from the power receiving device 101. The information about the remaining battery capacity is transmitted from the power receiving device 101 in a Charge Status Packet (CSP). Here, the remaining battery capacity is a value expressed as a percentage of the remaining battery capacity, with the energy in a fully charged state being 100%.

[0066] The control unit 300 of the power transmitting device 100 notifies the control unit 301 of the electronic device 102 of the received information on the remaining battery capacity of the battery 206. The control unit 301 of the electronic device 102 displays a remaining battery capacity 601 on the display unit 307 based on the information on the remaining battery capacity of the battery 206.

[0067] In step S703, the control unit 300 of the power transmitting device 100 determines whether the received remaining battery charge is equal to or greater than a transition threshold. The transition threshold is a value stored in the memory 306 of the power transmitting device 100, or a value acquired by the power transmitting device 100 from the power receiving device 101 during the connection sequence after transmitting power by Digital Ping. For example, the transition threshold is 99%. If the remaining battery charge is equal to or greater than the transition threshold, the control unit 300 proceeds to step S704, and if the remaining battery charge is less than the transition threshold, the control unit 300 returns to step S702.

[0068] In step S704, the control unit 300 of the power transmitting device 100 transitions from the normal mode to the power saving mode. In the power saving mode, the power transmitting device 100 transmits Analog Pings at longer intervals than in the normal mode.

[0069] Specifically, in the power saving mode, the power transmitting device 100 extends the time from receiving an End Power Transfer (EPT) packet, which is a request to end power transmission, from the power receiving device 101 to transmitting the next Analog Ping, compared to the normal mode. As an example, in the normal mode, it takes 100 ms for the power transmitting device 100 to transmit the Analog Ping after receiving the EPT packet. In the power saving mode, it takes 10 minutes for the power transmitting device 100 to transmit the Analog Ping after receiving the EPT packet.

[0070] As another method, in the power saving mode, the power transmitting device 100 may lengthen the interval between transmissions of Analog Pings compared to the normal mode. For example, the power transmitting device 100 stops power transmission when a condition for transitioning to the power saving mode is met. Alternatively, in the power saving mode, the power transmitting device 100 may specify a period during which transmission of Digital Pings is stopped. During the period during which transmission of Digital Pings is stopped, the power transmitting device 100 does not transmit Digital Pings after transmitting Analog Pings, thereby preventing the power transmitting device 100 from entering a power transmission state.

[0071] In step S705, the control unit 300 of the power transmitting device 100 receives an EPT packet from the power receiving device 101 and then stops transmitting power to the power receiving device 101. Note that the control unit 300 may stop transmitting power when the condition for transitioning to the power saving mode is met even if an EPT packet is not received.

[0072] In step S706, the control unit 300 of the power transmitting device 100 transmits an Analog Ping after a time set in the power saving mode has elapsed, and detects whether or not an object is placed on the power transmitting coil 304 of the power transmitting device 100. If the control unit 300 detects that an object is placed, it transmits a Digital Ping and detects whether or not the object is a power receiving device 101 that complies with the WPC standard. If the object is a power receiving device 101 that complies with the WPC standard, the control unit 300 proceeds to step S707. If the object is not a power receiving device 101 that complies with the WPC standard, or if no object is placed, the control unit 300 ends the processing of the flowchart in FIG. 7.

[0073] In step S707, the control unit 300 of the power transmitting device 100 starts transmitting power to the power receiving device 101. Prior to receiving the CSP from the power receiving device 101, the control unit 300 transmits an Analog Ping and a Digital Ping, but in the power saving mode, it takes a long time before transmitting the Analog Ping. Therefore, the time from stopping power transmission in step S705 to starting power transmission in step S707 is also long.

[0074] In step S708, the control unit 300 of the power transmitting device 100 receives the CSP including information on the remaining battery capacity of the battery 206 from the power receiving device 101. The control unit 300 notifies the control unit 301 of the electronic device 102 of the received information on the remaining battery capacity of the battery 206. The control unit 301 of the electronic device 102 displays the remaining battery capacity 601 on the display unit 307 based on the information on the remaining battery capacity of the battery 206.

[0075] In step S709, the control unit 300 of the power transmitting device 100 determines whether the remaining battery charge included in the CSP is equal to or less than the termination threshold. The termination threshold is a value stored in the memory 306 of the power transmitting device 100, or a value acquired by the power transmitting device 100 from the power receiving device 101 during the connection sequence after transmitting power by Digital Ping. For example, the termination threshold is 95%. If the remaining battery charge is equal to or less than the termination threshold, the control unit 300 proceeds to step S710, and if the remaining battery charge is not equal to or less than the termination threshold, the control unit 300 returns to step S705.

[0076] In step S710, the control unit 300 of the power transmitting device 100 ends the power saving mode and transitions to the normal mode. When ending the power saving mode, the control unit 300 sets the power transmission interval of the Analog Ping to the normal mode. The power transmission interval of the Analog Ping in the normal mode is shorter than the power transmission interval of the Analog Ping in the power saving mode. Specifically, the power transmitting device 100 shortens the time from receiving an EPT packet, which is a power transmission end request, from the power receiving device 101 to transmitting the next Analog Ping. As an example, the time from receiving an EPT packet to transmitting the Analog Ping by the power transmitting device 100 is 10 minutes in the power saving mode and 100 ms in the normal mode. As an alternative method, the power transmitting device 100 may shorten the interval between the transmission of the Analog Ping and the transmission of the Analog Ping.

[0077] In step S711, the control unit 300 of the power transmitting device 100 stops power transmission to the power receiving device 101, and the process returns to step S700.

[0078] In this way, by shifting from the normal mode to the power saving mode, the power transmitting device 100 can prevent the power transmission suspension time from becoming longer and the charging display from being frequently changed.

[0079] Fig. 8 is a sequence diagram showing a control method for the electronic device 102, the power transmitting device 100, and the power receiving device 101 according to this embodiment, and is a sequence diagram when applying the processing of the flowchart in Fig. 7. In the description of Fig. 8, the steps already described in Fig. 4 and Fig. 5 are assigned the same reference numerals, and description thereof will be omitted.

[0080] In step F400, the control unit 300 of the power transmitting device 100 transmits an Analog Ping to the power receiving device 101. In step F423, the power transmitting device 100 and the power receiving device 101 perform the processes of steps F401 to F416 in Fig. 4 already described, transition to the Power Transfer phase, and start power transmission.

[0081] In step F424, the power receiving device 101 transmits to the power transmitting device 100 a CSP (80%) including information that the remaining battery capacity of the battery 206 is 80%. In step S702, the control unit 300 of the power transmitting device 100 receives the CSP (80%) from the power receiving device 101. In step S703, the control unit 300 maintains the normal mode because the remaining battery capacity (80%) is not greater than or equal to the transition threshold value (99%), and returns to step S702.

[0082] In step F425, the control unit 300 of the power transmitting device 100 notifies the control unit 301 of the electronic device 102 that the remaining battery charge of the battery 206 is 80%. In step F426, the control unit 300 of the power transmitting device 100 notifies the control unit 301 of the electronic device 102 that power is being transmitted to the power receiving device 101 (i.e., the battery 206 is being charged).

[0083] In step F428, the control unit 301 of the electronic device 102 displays on the display unit 307, as shown in Fig. 6(b), that the remaining battery capacity 601 of the battery 206 is 80%. In step S431, the control unit 301 displays on the display unit 307, as shown in Fig. 6(b), a charging icon 602 indicating that the battery 206 is being charged.

[0084] In step F432, the power receiving device 101 transmits to the power transmitting device 100 a CSP (90%) including information that the remaining battery capacity of the battery 206 is 90%. In step S702, the control unit 300 of the power transmitting device 100 receives the CSP (90%) from the power receiving device 101. In step S703, since the remaining battery capacity (90%) is not greater than or equal to the transition threshold value (99%), the control unit 300 maintains the normal mode and returns to step S702.

[0085] In step F433, the control unit 300 of the power transmitting device 100 notifies the control unit 301 of the electronic device 102 that the remaining battery charge of the battery 206 is 90% and that power transmission is in progress. In step F444, the control unit 301 of the electronic device 102 displays on the display unit 307 the fact that the remaining battery charge 601 of the battery 206 is 90% and the charging icon 602.

[0086] In step F427, the power receiving device 101 transmits to the power transmitting device 100 a CSP (100%) including information that the remaining battery capacity of the battery 206 is 100%. In step S702, the control unit 300 of the power transmitting device 100 receives the CSP (100%) from the power receiving device 101. In step S703, the control unit 300 proceeds to step S704 because the remaining battery capacity (100%) is equal to or greater than the transition threshold value (99%).

[0087] The control unit 300 notifies the control unit 301 of the electronic device 102 that the remaining battery charge of the battery 206 is 100% and that power transmission is in progress. The control unit 301 of the electronic device 102 displays on the display unit 307 a message that the remaining battery charge 601 of the battery 206 is 100% and a charging icon 602, as shown in FIG. 6(c).

[0088] In step F432, the control unit 300 performs the process of step S704. In step S704, the control unit 300 transitions from the normal mode to the power saving mode, and changes the time TE from receiving an EPT packet to transmitting power for an Analog Ping from 100 ms to 10 minutes.

[0089] In step F422, the power receiving device 101 transmits an EPT packet to the power transmitting device 100 requesting that power transmission be stopped, since the remaining battery charge of the battery 206 is 100% and there is no longer any need to charge the battery 206. In step S705, upon receiving the EPT packet, the control unit 300 stops power transmission to the power receiving device 101.

[0090] In step F429, the control unit 300 of the power transmitting device 100 notifies the control unit 301 of the electronic device 102 that power transmission has been stopped due to the reception of the EPT packet. In step F430, the control unit 301 of the electronic device 102 displays on the display unit 307 that the remaining battery capacity 601 is 100%, as shown in FIG. 6(a), and stops displaying the charging icon 602.

[0091] In step F434, the control unit 300 of the power transmitting device 100 transmits an Analog Ping after a time TE (10 minutes) has elapsed since receiving the EPT packet in step F422 (S706). In step F435, the power transmitting device 100 and the power receiving device 101 perform the processes of steps F401 to F416 in Fig. 4, transition to the Power Transfer phase, and start transmitting power (S706 and S707).

[0092] In step F436, the power receiving device 101 transmits to the power transmitting device 100 a CSP(100%) including information that the remaining battery capacity of the battery 206 is 100%. In step S708, the control unit 300 of the power transmitting device 100 receives the CSP(100%) from the power receiving device 101. In step S709, since the remaining battery capacity (100%) is not less than or equal to the termination threshold (95%), the control unit 300 maintains the power saving mode, maintains the time TE of 10 minutes, and returns to step S705.

[0093] In step F437, the control unit 300 of the power transmitting device 100 notifies the control unit 301 of the electronic device 102 that the remaining battery charge of the battery 206 is 100%. In step F438, the control unit 300 of the power transmitting device 100 notifies the control unit 301 of the electronic device 102 that power is being transmitted to the power receiving device 101 (i.e., the battery 206 is being charged).

[0094] In step F439, the control unit 301 of the electronic device 102 displays on the display unit 307, as shown in Fig. 6(c), that the remaining battery capacity 601 of the battery 206 is 100%. In step S440, the control unit 301 displays on the display unit 307, as shown in Fig. 6(c), a charging icon 602 indicating that the battery 206 is being charged.

[0095] In step F441, the power receiving device 101 transmits an EPT packet to the power transmitting device 100 requesting that power transmission be stopped, since the remaining battery charge of the battery 206 is 100% and there is no longer any need to charge the battery 206. In step S705, upon receiving the EPT packet, the control unit 300 stops power transmission to the power receiving device 101.

[0096] In step F442, the control unit 300 of the power transmitting device 100 notifies the control unit 301 of the electronic device 102 that power transmission has been stopped due to the reception of the EPT packet. In step F443, the control unit 301 of the electronic device 102 displays on the display unit 307 that the remaining battery capacity 601 is 100%, as shown in FIG. 6(a), and stops displaying the charging icon 602.

[0097] In step F434, the control unit 300 of the power transmitting device 100 transmits an Analog Ping after a time TE (10 minutes) has elapsed since receiving the EPT packet in step F441 (S706). After that, the electronic device 102, the power transmitting device 100, and the power receiving device 101 repeat the processes from step F435 onwards.

[0098] Thereafter, the remaining battery charge of battery 206 gradually decreases. In step S709, when the remaining battery charge falls below the termination threshold (95%), control unit 300 proceeds to step S710, transitions to power saving mode, and sets time TE to 100 ms. In step S711, control unit 300 stops power transmission and returns to step S700.

[0099] As described above, in this embodiment, the control unit 300 determines whether to transition to the power saving mode according to the remaining battery capacity included in the CSP. When the remaining battery capacity reaches or exceeds the transition threshold (99%), the control unit 300 transitions to the power saving mode, and by setting a long time TE (10 minutes), the frequent repetition of starting and stopping power transmission is prevented. As a result, the display unit 307 does not rapidly blink the charging icon 602, thereby reducing annoyance to the user.

[0100] In addition, by setting the termination threshold (95%) lower than the transition threshold (99%), the control unit 300 suppresses frequent switching between normal mode and power saving mode, which has the effect of preventing rapid blinking of the charging icon 602 of the power receiving device 101 whose battery 206 is quickly depleted.

[0101] Although the example in which the power receiving apparatus 101 periodically transmits the CSP to the power transmitting apparatus 100 in the power transfer phase has been described, the power receiving apparatus 101 may transmit the CSP irregularly.

[0102] Furthermore, the power transmitting device 100 may periodically or irregularly request a CSP from the power receiving device 101, and the power receiving device 101 may notify the power transmitting device 100 of a CSP corresponding to the request. One method of making a request is to transmit a request packet from the power transmitting device 100 to the power receiving device 101. This request packet is a packet indicating that the power transmitting device 100 requests the power receiving device 101 to perform an operation. Thereafter, the power transmitting device 100 transmits a packet (requested operation identification packet) including identification information for identifying the operation requested by the power transmitting device 100 to the power receiving device 101. Note that these two operations may be performed in one packet. In other words, the power transmitting device 100 may transmit to the power receiving device 101 a packet indicating that the power transmitting device 100 requests the power receiving device 101 to perform an operation and including identification information for identifying the requested operation. Upon receiving this request packet and requested operation identification packet, the power receiving device 101 transmits the CSP to the power transmitting device 100.

[0103] Furthermore, the power transmitting device 100 may request a CSP from the power receiving device 101 when a predetermined condition is satisfied, and the power receiving device 101 may notify the power transmitting device 100 of a CSP corresponding to the request. For example, the predetermined condition is when the power transmitting device 100 receives an EPT packet from the power receiving device 101 multiple times (e.g., twice) within a certain time period (e.g., 10 seconds). In this case, the power transmitting device 100 receives the EPT packet in step F422, stops power transmission, and is ready to immediately transmit the next Analog Ping, so it is considered necessary to avoid the state shown in Fig. 5. In such a case, the power transmitting device 100 may obtain the remaining battery charge using the CSP and perform the control shown in Fig. 7.

[0104] In the negotiation phase, the power receiving device 101 may notify the power transmitting device 100 of the CSP, or the power transmitting device 100 may request a CSP from the power receiving device 101, and the power receiving device 101 may notify the power transmitting device 100 of the CSP corresponding to the request.

[0105] In the present embodiment, an example has been described in which predetermined fixed values ​​are used as the transition threshold and the termination threshold, but they may also be determined through negotiation between the power transmitting device 100 and the power receiving device 101 in the negotiation phase. For example, for a power receiving device 101 with a small capacity battery 206, the remaining charge of the battery 206 is likely to increase as the battery 206 is charged, so the termination threshold is set to a low value (e.g., termination threshold = 90%, transition threshold = 97%). This makes it possible to extend the time interval during which the charging icon 602 is repeatedly displayed and hidden. For this reason, the power receiving device 101 may negotiate a low transition threshold value in the negotiation.

[0106] As described above, the power transmitting unit 303 wirelessly transmits power to the power receiving device 101. When the power transmitting unit 303 is transmitting power, the control unit 301 controls the power receiving device 101 to display a charging icon 602 indicating that the power receiving device 101 is charging. Furthermore, when the power transmitting unit 303 has stopped transmitting power, the control unit 301 controls the power receiving device 101 to stop displaying the charging icon 602 indicating that the power receiving device 101 is charging.

[0107] The power transmitting unit 303 transitions from a normal mode to a power saving mode in which the period from when the power transmitting unit 303 stops transmitting power until when it starts transmitting power for object detection is longer than in the normal mode, based on information from the power receiving device 101. The information from the power receiving device 101 is, for example, the remaining battery capacity of the power receiving device 101. The communication unit 305, as a receiving unit, receives the remaining battery capacity of the power receiving device 101 from the power receiving device 101.

[0108] The time TE (10 minutes) from when the power transmitting unit 303 stops transmitting power until when it starts transmitting power in the power saving mode is longer than the time TE (100 ms) from when the power transmitting unit 303 stops transmitting power until when it starts transmitting power in the normal mode. The power transmission suspension period in the power saving mode is longer than the power transmission suspension period in the normal mode. Note that the interval between Analog Pings transmitted by the power transmitting unit 303 in the power saving mode may be longer than the interval between Analog Pings transmitted by the power transmitting unit 303 in the normal mode.

[0109] In step S703, if the remaining battery charge of the power receiving apparatus 101 is greater than the transition threshold, the power transmitting unit 303 proceeds to step S704 and transitions to the power saving mode. In step S709, if the remaining battery charge of the power receiving apparatus 101 is less than the termination threshold, the power transmitting unit 303 proceeds to step S710 and transitions to the normal mode. The termination threshold is equal to or less than the transition threshold.

[0110] In steps S702 and S708, the communication unit 305 receives the remaining battery charge of the power receiving device 101 by a Charge Status Packet of the WPC standard. The communication unit 305 receives the remaining battery charge of the power receiving device 101 superimposed on the power of the power transmitting unit 303 from the power receiving device 101. The communication unit 305 receives the remaining battery charge of the power receiving device 101 by ASK modulation or FSK modulation.

[0111] Note that the communication unit 305 may function as a transmission unit to transmit a request for the remaining battery capacity of the power receiving device 101 to the power receiving device 101, and receive the remaining battery capacity of the power receiving device 101 corresponding to the request from the power receiving device 101. The communication unit 305 may also receive the remaining battery capacity of the power receiving device 101 according to the Bluetooth Low Energy standard.

[0112] According to this embodiment, in the power saving mode, the electronic device 102 can lengthen the time TE from when the display indicating that the power receiving device 101 is charging is stopped to when the display indicating that the power receiving device 101 is charging is started. This makes it possible for the electronic device 102 to prevent the display indicating that the power receiving device 101 is charging and the display indicating that the power receiving device 101 is charging from being repeatedly stopped at high speed.

[0113] (Second embodiment) In the first embodiment, the power transmitting device 100 transitions to a power saving mode and sets a long time TE (10 minutes) in accordance with the remaining battery capacity included in the received CSP. In the second embodiment, the power transmitting device 100 requests temperature information from the power receiving device 101, transitions to a power saving mode in accordance with the received temperature information, and sets a long time TE (10 minutes).

[0114] Fig. 9 is a flowchart illustrating power saving mode processing of the power transmitting device 100 according to the second embodiment. In Fig. 9, steps S702, S703, S708, and S709 are deleted from Fig. 7, and steps S901 to S906 are added. The same contents in Fig. 9 as those in Fig. 7 are given the same reference numerals, and the explanation will be simplified. Below, the differences between the second embodiment and the first embodiment will be explained.

[0115] In step S700, the control unit 300 of the power transmitting device 100 transmits an Analog Ping and detects whether an object is placed on the power transmitting coil 304 of the power transmitting device 100. If the control unit 300 detects that an object is placed, it transmits a Digital Ping and detects whether the object is a power receiving device 101 that complies with the WPC standard. If the object is a power receiving device 101 that complies with the WPC standard, the control unit 300 proceeds to step S701. If the object is not a power receiving device 101 that complies with the WPC standard or if no object is placed, the control unit 300 ends the processing of the flowchart in FIG. 9.

[0116] In step S701, the control unit 300 of the power transmitting apparatus 100 starts transmitting power to the power receiving apparatus 101.

[0117] In step S901, the control unit 300 of the power transmitting device 100 requests the power receiving device 101 to transmit the transition temperature and the current temperature as temperature information of the power receiving device 101. The transition temperature corresponds to the transition threshold. In response to the request, the power receiving device 101 transmits the transition temperature and the current temperature to the power transmitting device 100 as temperature information of the power receiving device 101.

[0118] In step S902, the control unit 300 of the power transmitting device 100 receives from the power receiving device 101, as temperature information of the power receiving device 101, the transition temperature (for example, 70° C.) and the current temperature (for example, 60° C.).

[0119] In step S903, the control unit 300 of the power transmitting device 100 sets the transition temperature of the power receiving device 101 as a transition threshold, and determines whether the current temperature of the power receiving device 101 is equal to or greater than the transition threshold. If the current temperature of the power receiving device 101 is not equal to or greater than the transition threshold, the control unit 300 returns to step S901, and if the current temperature of the power receiving device 101 is equal to or greater than the transition threshold, the control unit 300 proceeds to step S704.

[0120] In step S704, the control unit 300 of the power transmitting device 100 transitions from the normal mode to the power saving mode, and sets the time TE to 10 minutes.

[0121] In step S705, the control unit 300 of the power transmitting apparatus 100 receives the EPT packet from the power receiving apparatus 101 and then stops power transmission to the power receiving apparatus 101.

[0122] In step S706, the control unit 300 of the power transmitting device 100 transmits an Analog Ping after a time TE has elapsed, and detects whether an object is placed on the power transmitting coil 304 of the power transmitting device 100. If the control unit 300 detects that an object is placed, it transmits a Digital Ping and detects whether the object is a power receiving device 101 that complies with the WPC standard. If the object is a power receiving device 101 that complies with the WPC standard, the control unit 300 proceeds to step S707. If the object is not a power receiving device 101 that complies with the WPC standard, or if no object is placed, the control unit 300 ends the processing of the flowchart in FIG. 9.

[0123] In step S707, the control unit 300 of the power transmitting apparatus 100 starts transmitting power to the power receiving apparatus 101.

[0124] In step S904, the control unit 300 of the power transmitting device 100 requests the power receiving device 101 to transmit the end temperature and the current temperature as temperature information of the power receiving device 101. The end temperature corresponds to the end threshold. In response to the request, the power receiving device 101 transmits the end temperature and the current temperature to the power transmitting device 100 as temperature information of the power receiving device 101.

[0125] In step S902, the control unit 300 of the power transmitting device 100 receives the end temperature (for example, 65° C.) and the current temperature from the power receiving device 101 as temperature information of the power receiving device 101.

[0126] In step S903, the control unit 300 of the power transmitting device 100 sets the end temperature of the power receiving device 101 as the end threshold, and determines whether the current temperature of the power receiving device 101 is equal to or lower than the end threshold. If the current temperature of the power receiving device 101 is not equal to or lower than the end threshold, the control unit 300 returns to step S705, and if the current temperature of the power receiving device 101 is equal to or lower than the end threshold, the control unit 300 proceeds to step S710. Note that the transition threshold and the end threshold may be values ​​stored in the memory 306 of the power transmitting device 100, or values ​​acquired by the power transmitting device 100 from the power receiving device 101 during the connection sequence after power transmission by Digital Ping.

[0127] In step S710, the control unit 300 of the power transmitting device 100 ends the power saving mode, transitions to the normal mode, and sets the time TE to 100 ms.

[0128] In step S711, the control unit 300 of the power transmitting device 100 stops power transmission to the power receiving device 101, and the process returns to step S700.

[0129] As described above, according to this embodiment, the control unit 300 transitions to the power saving mode when the temperature of the power receiving device 101 is equal to or higher than the transition threshold, and terminates the power saving mode when the temperature of the power receiving device 101 is equal to or lower than the termination threshold. This allows the control unit 300 to prevent the power transmission suspension time from becoming longer in the power saving mode, and to prevent the display of the charging icon 602 from being frequently changed.

[0130] As described above, the power transmitting unit 303 transitions from the normal mode to the power saving mode, in which the period from when the power transmitting unit 303 stops transmitting power until when it starts transmitting power for object detection is longer than in the normal mode, based on information from the power receiving device 101. The information from the power receiving device 101 is, for example, the temperature of the power receiving device 101.

[0131] In step S903, if the temperature of the power receiving device 101 is greater than the transition threshold, the power transmitting unit 303 proceeds to step S704 and transitions to the power saving mode. In step S906, if the temperature of the power receiving device 101 is less than the termination threshold, the power transmitting unit 303 proceeds to step S710 and transitions to the normal mode. The termination threshold is equal to or less than the transition threshold.

[0132] In steps S901 and S904, the communication unit 305 transmits a request for the temperature of the power receiving device 101 to the power receiving device 101. In steps S902 and S905, the communication unit 305 receives the temperature of the power receiving device 101 corresponding to the request from the power receiving device 101. The communication unit 305 receives the temperature of the power receiving device 101 superimposed on the power of the power transmitting unit 303 from the power receiving device 101. The communication unit 305 receives the temperature of the power receiving device 101 using ASK modulation or FSK modulation. Note that the communication unit 305 may also receive the temperature of the power receiving device 101 according to the Bluetooth Low Energy standard.

[0133] According to this embodiment, in the power saving mode, the electronic device 102 can lengthen the time TE from when the display indicating that the power receiving device 101 is charging is stopped to when the display indicating that the power receiving device 101 is charging is started. This makes it possible for the electronic device 102 to prevent the display indicating that the power receiving device 101 is charging and the display indicating that the power receiving device 101 is charging from being repeatedly stopped at high speed.

[0134] (Other embodiments) In the first and second embodiments, the power transmitting device 100 receives the remaining charge of the battery 206 or the temperature of the power receiving device 101 from the power receiving device 101, but this is not limiting. The power transmitting device 100 may acquire the remaining charge of the battery 206 or the temperature of the power receiving device 101 from the power receiving device 101 through Bluetooth Low Energy (BLE) communication. In this case, the communication units 305 and 204 of the power transmitting device 100 and the power receiving device 101 are capable of BLE communication.

[0135] Furthermore, the control unit 300 may transition to the power saving mode and stop wireless power transmission when it acquires wired charging start information due to a wired charging cable being connected between the power transmitting device 100 and the power receiving device 101. Furthermore, when the wired charging cable between the power transmitting device 100 and the power receiving device 101 is disconnected, the control unit 300 ends the power saving mode and transitions to the normal mode.

[0136] Based on information from the power receiving device 101, the power transmitting unit 303 transitions from the normal mode to a power saving mode in which the period from when the power transmitting unit 303 stops power transmission until when it starts transmitting power for object detection is longer than in the normal mode. The information from the power receiving device 101 is, for example, information that the electronic device 102 or the power transmitting device 100 has started transmitting power via a wire to the power receiving device 101. Furthermore, when the electronic device 102 or the power transmitting device 100 has finished transmitting power via a wire to the power receiving device 101, the power transmitting unit 303 transitions from the power saving mode to the normal mode.

[0137] 7 to 9 can be realized, for example, by the control units 200, 300, and 301 reading and executing a pre-stored program to control each functional unit. However, this is not limiting, and at least a part of these processes may be realized by hardware. When realized by hardware, for example, a predetermined compiler is used to automatically generate a dedicated circuit on an FPGA from a program for realizing each processing step. Here, FPGA is an acronym for Field Programmable Gate Array. Also, a gate array circuit may be formed in a similar manner to an FPGA to realize hardware that executes at least a part of the above-described processes.

[0138] It should be noted that the above-described embodiments merely illustrate specific examples of implementing the present disclosure, and the technical scope of the present disclosure should not be construed as being limited by these embodiments. In other words, the present disclosure can be implemented in various forms without departing from its technical concept or main features. [Explanation of symbols]

[0139] 100 power transmitting device, 101 power receiving device, 102 electronic device, 301 control unit, 303 power transmitting unit

Claims

1. a power transmitting means for wirelessly transmitting power to a power receiving device; a control means for controlling the display of the fact that the power receiving device is being charged when the power transmitting means is transmitting power, and for controlling the display of the fact that the power receiving device is being charged to be stopped when the power transmitting means has stopped transmitting power; The power transmission means is when a remaining battery charge of the power receiving device based on the information of the power receiving device is greater than a first threshold, transitioning from a normal mode to a power saving mode in which a period from when the power transmitting means stops transmitting power to when the power transmitting means starts transmitting power for object detection is longer than in the normal mode; In the power saving mode, when a remaining battery capacity of the power receiving device based on information of the power receiving device becomes smaller than a second threshold, the power receiving device transitions to the normal mode; The second threshold is smaller than the first threshold. An electronic device characterized by:

2. the information about the power receiving device is a remaining battery charge of the power receiving device; 2. The electronic device according to claim 1, further comprising a receiving unit that receives a remaining battery charge of the power receiving device from the power receiving device.

3. the information about the power receiving device is a temperature of the power receiving device, 2. The electronic device according to claim 1, further comprising a receiving unit that receives the temperature of the power receiving device from the power receiving device.

4. The electronic device according to claim 1 , wherein the information about the power receiving device is information that the electronic device has started transmitting power to the power receiving device via a wire.

5. 5. The electronic device according to claim 1, wherein the interval at which the power transmitting unit transmits power in the power saving mode is longer than the interval at which the power transmitting unit transmits power in the normal mode.

6. 4. The electronic device according to claim 3, wherein the power transmitting means transitions to the power saving mode when the temperature of the power receiving device is higher than a first threshold value.

7. 7. The electronic device according to claim 6, wherein the power transmitting unit transitions to the normal mode when the temperature of the power receiving device is lower than a second threshold value.

8. 8. The electronic device according to claim 7, wherein the second threshold value is equal to or less than the first threshold value.

9. 5. The electronic device according to claim 4, wherein the power transmission unit transitions to the normal mode when the electronic device has finished transmitting power to the power receiving device via a wire.

10. 3. The electronic device according to claim 2, wherein the receiving means receives the remaining battery capacity of the power receiving device by a Charge Status Packet of the WPC standard.

11. a transmitting unit for transmitting a request for the remaining battery capacity or temperature of the power receiving device to the power receiving device; 4. The electronic device according to claim 2, wherein the receiving unit receives, from the power receiving device, the remaining battery capacity or the temperature of the power receiving device in response to the request.

12. 4. The electronic device according to claim 2, wherein the receiving means receives from the power receiving device the remaining battery charge or the temperature of the power receiving device superimposed on the power.

13. 13. The electronic device according to claim 12, wherein the receiving means receives the remaining battery charge or temperature of the power receiving device by ASK modulation or FSK modulation.

14. 4. The electronic device according to claim 2, wherein the receiving means receives the remaining battery charge or temperature of the power receiving device in accordance with the Bluetooth Low Energy standard.

15. a power transmitting step of wirelessly transmitting power to a power receiving device; a control step of controlling the power receiving device to display a message indicating that the power receiving device is being charged when power transmission is in progress, and to stop displaying the message indicating that the power receiving device is being charged when power transmission is stopped; when a remaining battery charge of the power receiving device based on the information of the power receiving device is greater than a first threshold, transitioning from a normal mode to a power saving mode in which a period from stopping power transmission to starting power transmission for object detection is longer than in the normal mode; a transition step of transitioning to the normal mode when a remaining battery capacity of the power receiving device based on information about the power receiving device becomes smaller than a second threshold in the power saving mode; The second threshold is smaller than the first threshold. A method for controlling an electronic device.

16. A program for causing a computer to function as the electronic device according to any one of claims 1 to 14.

Images