Electronic device, its control method, and program

Abstract

To reduce a startup time period of a device requiring initialization while suppressing power consumption of a battery.SOLUTION: An electronic apparatus 100 includes: a main controller 101; a sub controller 102; a main battery 120; a power reception controller 125 configured to extract electric power from radio waves; and a power supply controller 124 configured to control supply of electric power from the main battery 120 or the power reception controller 125 to the main controller 101. The sub controller 102 performs control so as to supply electric power to the power supply controller 124 from the main battery 120 in a power-on mode in which power consumption of the electronic apparatus 100 is large, and to switch the power supply source to the power reception controller 125 when transitioning to a power-off mode in which the power consumption is smaller than in the power-on mode.SELECTED DRAWING: Figure 2

Description

[Technical Field]

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

[0002] For example, in electronic devices with a photographing function, such as digital cameras and smartphones, there is a demand for shortening the startup time when the electronic device is started from a powered-off state so that users do not miss a photographing opportunity (a shutter chance).

[0003] When an electronic device is turned on, it is generally necessary to perform initial settings to operate various devices within the device, such as the power supply IC and microcomputer. This initial setting involves, for example, writing the initial settings from non-volatile memory to the device's volatile memory and expanding the control program. Volatile memory can retain information (data) while power is being supplied, so by configuring the device so that power continues to be supplied to volatile memory even when the electronic device is turned off, the startup time when the power is turned on can be shortened.

[0004] However, portable electronic devices such as digital cameras and smartphones generally use batteries as their power source. Therefore, if power is continuously supplied to devices such as volatile memory, power is consumed even when the device is turned off, shortening the battery life of the device. Therefore, it is desirable to cut off power to devices that consume large amounts of power when the device is turned off. However, cutting off power to such devices increases startup time because the device must be initialized each time the device is turned on. In other words, there is a trade-off between shortening startup time and improving power-saving performance.

[0005] To address this problem, for example, Patent Document 1 discloses a technology that shortens startup time by temporarily storing settings in non-volatile memory when the electronic device is turned off, and then expanding and starting up the settings temporarily stored in non-volatile memory when the electronic device is restarted (powered on). [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2013-215976 Summary of the Invention [Problem to be solved by the invention]

[0007] However, the technology disclosed in Patent Document 1 requires that settings temporarily stored in non-volatile memory be expanded into the volatile memory of the target device, which results in a longer startup time than if power were continuously supplied to the target device.

[0008] The present invention aims to provide an electronic device that can reduce the startup time of a device that requires initial setup while suppressing battery power consumption. [Means for solving the problem]

[0009] An electronic device according to the present invention is an electronic device comprising first control means, second control means, a battery, power receiving control means for extracting power from radio waves, and power supply control means for controlling the supply of power from the battery or the power receiving control means to the second control means, wherein the first control means switches the supply of power to the power control means from the battery in a first operation mode in which the electronic device consumes more power, and from the power receiving control means when the electronic device transitions to a second operation mode in which the power consumption is lower than that of the first operation mode. The power supply control means and the second control means each have a volatile storage area for storing settings when operating in the first operation mode, and in the second operation mode, at least the settings stored in the volatile storage area of ​​the power supply control means are maintained. It is characterized by: [Effects of the Invention]

[0010] According to the present invention, it is possible to reduce the startup time of a device that requires initial setup while suppressing battery power consumption. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a block diagram showing a configuration of an electronic device according to a first embodiment. [Figure 2] 2 is a block diagram showing the configuration of a power supply control unit and its peripherals of the electronic device; [Figure 3] 4 is a flowchart illustrating startup control of the electronic device according to the first embodiment. [Figure 4] 4 is a diagram showing a transition time from a power-off mode to a power-on mode in the startup control of FIG. 3. FIG. [Figure 5] 10 is a flowchart illustrating startup control of an electronic device according to a second embodiment. [Figure 6] 10A and 10B are diagrams illustrating power supply control modes in startup control according to the second embodiment. [Figure 7] 6 is a diagram showing a transition time from a power-off mode to a power-on mode in the startup control of FIG. 5. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0012] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Fig. 1 is a block diagram showing a schematic configuration of an electronic device 100 according to an embodiment of the present invention.

[0013] The electronic device 100 includes a main control unit 101, a sub-control unit 102, a storage unit 103, a power switch 104, a main battery 120, an auxiliary battery 121, a first battery detection unit 122, a second battery detection unit 123, a power control unit 124, and a power receiving control unit 125. The electronic device 100 includes a first wireless communication control unit 150, a second wireless communication control unit 151, a third wireless communication control unit 152, a fourth wireless communication control unit 153, a first rectifier circuit 160, a second rectifier circuit 161, and a third rectifier circuit 162. The electronic device 100 includes a first switching circuit 163, a second switching circuit 164, a third switching circuit 165, a fourth switching circuit 166, a first input filter circuit 168, a second input filter circuit 169, and a third input filter circuit 170. The electronic device 100 includes a first antenna matching circuit 171, a second antenna matching circuit 172, a third antenna matching circuit 173, a first antenna 175, a second antenna 176, and a third antenna 177.

[0014] The electronic device 100 is a device that operates using a main battery 120 as a power source under normal use conditions, and is typified by mobile devices such as digital cameras, smartphones, and tablet PCs.

[0015] The main control unit 101 is a microcomputer including, for example, a CPU, a ROM, a RAM, etc., and controls the overall operation of the electronic device 100. The sub-control unit 102 is a microcomputer including a CPU, a ROM, a RAM, etc., and is configured to operate with lower power consumption than the main control unit 101, and plays a role in assisting the main control unit 101 in controlling the operation of the electronic device 100. The memory unit 103 is configured to be able to store and hold various setting information and the like even when no power source (electricity) is supplied, and to be able to communicate with the main control unit 101.

[0016] The power switch 104 is operated by a user to turn the power of the electronic device 100 on / off. The on / off switching of the power switch 104 is detected by the sub-control unit 102. The main battery 120 is the main power source that operates the electronic device 100, and is, for example, a secondary battery such as a rechargeable lithium-ion battery. The auxiliary battery 121 is, for example, a coin battery that has a smaller battery capacity than the main battery 120 and serves to assist the operation of the electronic device 100 when there is no main power source (for example, when the main battery 120 is removed). Note that a rechargeable secondary battery is used as the auxiliary battery 121. The first battery detection unit 122 detects whether the main battery 120 is installed and the remaining battery power of the installed main battery 120. The second battery detection unit 123 detects the remaining battery power of the auxiliary battery 121.

[0017] The power supply control unit 124 receives power from the main battery 120 and the power receiving control unit 125, and controls the power supply of the electronic device 100 by supplying power to the main control unit 101, the sub-control unit 102, the storage unit 103, etc. The detailed configuration of the power supply control unit 124 will be described later. The power receiving control unit 125 controls the power generated using radio waves such as microwaves. The power receiving detection unit 126 detects the amount of power received by the power receiving control unit 125, etc.

[0018] The first wireless communication control unit 150 controls wireless communication such as wireless LAN using radio waves in the 2.4 GHz band. The second wireless communication control unit 151 controls wireless communication such as Bluetooth (registered trademark) using radio waves in the 2.4 GHz band. The second wireless communication control unit 151 consumes less power than the first wireless communication control unit 150 and can operate using power supplied from the auxiliary battery 121. The third wireless communication control unit 152 controls wireless communication such as wireless LAN using radio waves in the 5 GHz band, which is a frequency band used for communication different from that used for communication by the first wireless communication control unit 150. The fourth wireless communication control unit 153 controls wireless communication in a fifth-generation communication system using radio waves in the 28 GHz band, which is a frequency band used for communication different from that used for communication by the first wireless communication control unit 150 and the third wireless communication control unit 152.

[0019] The first rectifier circuit 160 rectifies communication radio waves in the frequency band used for communication by the first wireless communication control unit 150 and the second wireless communication control unit 151, and supplies power to the power receiving control unit 125. The second rectifier circuit 161 rectifies communication radio waves in the frequency band used for communication by the third wireless communication control unit 152, and supplies power to the power receiving control unit 125. The third rectifier circuit 162 rectifies communication radio waves in the frequency band used for communication by the fourth wireless communication control unit 153, and supplies power to the power receiving control unit 125.

[0020] The first switching circuit 163 switches between the first wireless communication control unit 150 and the second wireless communication control unit 151, which use the same frequency band. The second switching circuit 164 switches between performing wireless communication using the first wireless communication control unit 150 or the second wireless communication control unit 151, or supplying wireless communication radio waves as power to the power receiving control unit 125 via the first rectifier circuit 160. The third switching circuit 165 switches between the first antenna matching circuit 171 and the second antenna matching circuit 172. The fourth switching circuit 166 switches between performing wireless communication using the third wireless communication control unit 152, or supplying wireless communication radio waves as power to the power receiving control unit 125 via the second rectifier circuit 161. The fifth switching circuit 167 switches between performing wireless communication using the fourth wireless communication control unit 153, or supplying wireless communication radio waves as power to the power receiving control unit 125 via the third rectifier circuit 162.

[0021] The first input filter circuit 168 passes the frequency band used for communication by the first wireless communication control unit 150 or the second wireless communication control unit 151. The second input filter circuit 169 passes the frequency band used for communication by the third wireless communication control unit 152. The third input filter circuit 170 passes the frequency band used for communication by the fourth wireless communication control unit 153.

[0022] First antenna matching circuit 171 matches the impedance with first antenna 175 at the operating frequency. Second antenna matching circuit 172 matches the impedance with first antenna 175 at the operating frequency, but differs from first antenna matching circuit 171 in that it matches at a different frequency within the same communication frequency band. Third antenna matching circuit 173 matches the impedance with second antenna 176 at the operating frequency. Fourth antenna matching circuit 174 matches the impedance with third antenna 177 at the operating frequency.

[0023] The first antenna 175 receives radio waves in the frequency band used by the first wireless communication control unit 150 and the second wireless communication control unit 151. The second antenna 176 receives radio waves in the frequency band used by the third wireless communication control unit 152. The third antenna 177 receives radio waves in the frequency band used by the fourth wireless communication control unit 153.

[0024] Next, the configuration of the power supply control unit 124 and its periphery will be described in detail. Fig. 2 is a block diagram showing the configuration of the power supply control unit 124 and its periphery.

[0025] The power supply control unit 124 has a first power supply unit 201 and a second power supply unit 202. The first power supply unit 201 can receive power from both the main battery 120 and the power receiving control unit 125 and is configured, for example, by a DC-DC converter capable of supplying large amounts of power. The power generated by the first power supply unit 201 is supplied to the main control unit 101 and the storage unit 103. The path for supplying power from the main battery 120 to the first power supply unit 201 is configured to be switchable between energized and cut-off states by the sub-control unit 102 controlling the opening and closing of a switch 203. By opening the switch 203 to cut off the power supply, the power supply from the main battery 120 to the first power supply unit 201 is stopped, thereby reducing the power consumption of the main battery 120. The second power supply unit 202 can receive power from the main battery 120 and is configured, for example, by a linear regulator. The power generated by the second power supply unit 202 is supplied to the sub-control unit 102.

[0026] The main control unit 101 has a second operation control unit 204 and a first operation control unit 205. Power for the second operation control unit 204, the first operation control unit 205, and the storage unit 103 is supplied by a first power supply unit 201. The power supply to the second operation control unit 204, the first operation control unit 205, and the storage unit 103 can be cut off by the sub-control unit 102 controlling the opening and closing of switches 206, 207, and 208, respectively.

[0027] The first operation control unit 205 is, for example, a microcomputer that controls the overall operation of the electronic device 100, and has more control resources than the second operation control unit 204. The second operation control unit 204 is a microcomputer that operates with lower power consumption than the first operation control unit 205, and executes processes that the first operation control unit 205 does not execute (for example, updating the display content of a display panel (not shown) of the electronic device 100, etc.).

[0028] For simplicity of explanation, in the electronic device 100, the main control unit 101 is configured from two operation control units: a first operation control unit 205 and a second operation control unit 204. However, the main control unit 101 can be configured from one or three or more operation control units depending on the functional configuration.

[0029] Next, startup control according to the first embodiment when starting up the electronic device 100 from a power-off state will be described. Fig. 3 is a flowchart illustrating startup control according to the first embodiment of the electronic device 100. Each process (step) indicated by an S number in the flowchart of Fig. 3 is realized by the main control unit 101 and the sub-control unit 102 executing a predetermined program, respectively, to control the operation of each unit of the electronic device 100. Note that predetermined processes among the processes shown in the flowchart of Fig. 3 are executed by predetermined processing units controlled by the main control unit 101 and the sub-control unit 102.

[0030] The startup control shown in the flowchart of Fig. 3 is started, for example, when the user switches the power switch 104 from off to on. Also, at the start of the processing of the flowchart (when the power switch 104 is off), the switch 203 shown in Fig. 2 is in the off state, and the switches 206, 207, and 208 are in the on state. Note that when power is supplied to each unit (device) from the main battery 120 and the power control unit 124 and the electronic device 100 is not being operated, each unit to which power is supplied is controlled to the off state by the sub-control unit 102 in order to save power.

[0031] When the power switch 104 is switched from off to on, the sub-control unit 102 performs processing to transition itself to a power-on mode (first operation mode) in S301. In S302, the sub-control unit 102 determines whether or not power is being supplied from the power receiving control unit 125 to the first power supply unit 201. Specifically, the determination in S302 is processing to confirm whether or not the processing in S311 has been performed later. If the sub-control unit 102 determines that power is not being supplied from the power receiving control unit 125 to the first power supply unit 201 (No in S302), the processing proceeds to S303. Note that when the power switch 104 is turned on for the first time with the main battery 120 attached to the electronic device 100, power supply from the main battery 120 starts, and therefore the processing always proceeds to S303. On the other hand, if the sub-control unit 102 determines in the determination process of S302 that power is being supplied from the power receiving control unit 125 to the first power supply unit 201 (Yes in S302), the sub-control unit 102 advances the process to S306.

[0032] In S303, the sub-control unit 102 supplies power from the main battery 120 to the first power supply unit 201 and performs initial settings of the first power supply unit 201. Specifically, the sub-control unit 102 writes settings (such as voltage value and output timing) required for power output from the first power supply unit 201 to a volatile register area inside the first power supply unit 201.

[0033] In S304, the first power supply unit 201 starts supplying power to the main control unit 101 and the storage unit 103 in accordance with the settings made by the sub-control unit 102. In S305, the main control unit 101 loads the program stored in the non-volatile storage area of ​​the storage unit 103 into a volatile storage area inside the main control unit 101, thereby transitioning the entire system of the electronic device 100 to a power-on mode. When the system of the electronic device 100 is thus activated, the main control unit 101 advances the process to S308.

[0034] In S306, the sub-control unit 102 controls the switch 203 to turn on, and switches the power supply to the first power supply unit 201 from the power receiving control unit 125 to the main battery 120. This is for the following reason: In S302, it is determined that power is being supplied from the power receiving control unit 125 to the first power supply unit 201 while the power switch 104 of the electronic device 100 is in the off state. This is because it indicates that various data stored in the volatile storage areas of the first power supply unit 201, the main control unit 101, and the storage unit 103 is being maintained by the power supply from the power receiving control unit 125 while the power switch 104 is in the off state.

[0035] In S307, the main control unit 101 transitions the entire system of the electronic device 100 to a power-on mode by sequentially executing programs deployed in a volatile storage area inside the main control unit 101. When the system of the electronic device 100 is thus activated, the main control unit 101 advances the process to S308.

[0036] In S308, the main control unit 101 sequentially executes programs deployed in a volatile storage area inside the main control unit 101, thereby performing normal operation in response to user operations on the electronic device 100. In S309, the sub-control unit 102 determines whether the power switch 104 has been switched from on to off. If the sub-control unit 102 determines that the power switch 104 remains on (No in S309), it repeats the determination in S309 while continuing normal operation, and if it determines that the power switch 104 has been switched off (Yes in S309), it proceeds to S310.

[0037] In S310, the main control unit 101 and the sub-control unit 102 perform processing to transition the electronic device 100 to a power-off mode (second operation mode). Specifically, in S310, the processing to transition to a low power consumption mode is performed by reducing the speed of the internal clock and stopping the operation of predetermined circuit blocks. In S311, the sub-control unit 102 controls the power receiving control unit 125 so that power is supplied from the power receiving control unit 125 to the first power supply unit 201, and turns off the switch 203 after power is output from the power receiving control unit 125, thereby ending this processing. This is to reduce power consumption of the main battery 120 by preventing power from being supplied from the main battery 120 to the first power supply unit 201.

[0038] Next, the effects obtained by the processing according to the flowchart of Fig. 3 will be described. Fig. 4(a) is a diagram showing the startup time (transition time from power-off mode to power-on mode) required when the system of the electronic device 100 is started from a state in which power is not supplied to the first power supply unit 201 when the electronic device 100 is powered off. Fig. 4(b) is a diagram showing the startup time required when the system of the electronic device 100 is started from a state in which power is supplied from the power receiving control unit 125 to the first power supply unit 201 when the electronic device 100 is powered off. Note that the S numbers shown in Figs. 4(a) and (b) correspond to the S numbers in the flowchart of Fig. 3. For example, S301 in Figs. 4(a) and (b) indicates the time required for the processing of S301 in the flowchart of Fig. 3.

[0039] In the case of Fig. 4(a), it takes time Ta to start up the system of electronic device 100, but in the case of Fig. 4(b), the start-up is completed in time Tb, which is shorter than time Ta. In other words, by performing processing via the route of S306 and S307 in the flowchart of Fig. 3, it is possible to shorten the start-up time by 'Ta - Tb' compared to processing via the route of S303 to S305 in the flowchart.

[0040] In this embodiment, a type of energy harvesting technology is used to convert microwaves from wireless LAN, mobile phone communications, etc. into power, and power is supplied from the power receiving control unit 125 to the main control unit 101 and the storage unit 103 via the first power supply unit 201. This makes it possible to reduce the power consumption of the main battery 120, and also makes it possible to reduce the size of the main battery 120 by reducing its capacity, and further makes it possible to shorten the startup time compared to conventional startup methods for electronic devices.

[0041] In a configuration in which settings are temporarily stored in a nonvolatile memory to maintain the settings when the power is turned off, as in the technology described in Patent Document 1, the nonvolatile memory for temporary storage requires a storage capacity according to the amount of data to be stored. In this case, if the amount of data is large, the cost required for implementing the nonvolatile memory for temporary storage may increase, but in this embodiment, a nonvolatile memory for temporary storage is not required, and an increase in cost can be avoided.

[0042] Next, startup control according to the second embodiment when starting up the electronic device 100 from a power-off state will be described. In the above first embodiment, a configuration was described in which the time required to start up the system of the electronic device 100 is shortened by using the power output from the power receiving control unit 125 to drive the power supply control unit 124. Also, in the first embodiment, power is supplied to the power supply control unit 124 regardless of the power supply state from the power receiving control unit 125, thereby shortening the system startup time.

[0043] When converting radio waves into electric power, there are cases where sufficient power cannot be extracted or the extractable power varies depending on the radio wave conditions. Therefore, if an attempt is made to shorten the system startup time of the electronic device 100 as in the first embodiment when the power supply to the power supply control unit 124, the main control unit 101, and the storage unit 103 is insufficient, there is a risk that the settings written in the volatile storage areas of each device will be lost. In such cases, there is a possibility that the electronic device 100 will not be able to start up normally.

[0044] In the second embodiment, a configuration that solves these problems will be described. Note that the block configuration of the electronic device 100 is similar to that shown in Figures 1 and 2 and the explanation thereof, and therefore a description thereof will be omitted. In the second embodiment, startup control is performed according to the flowchart of Figure 5, which will be described below, instead of the startup control flowchart corresponding to Figure 3 in the first embodiment.

[0045] Fig. 5 is a flowchart illustrating startup control according to a second embodiment of the electronic device 100. The startup control shown in the flowchart of Fig. 5 is initiated, for example, when a user switches the power switch 104 from off to on. Furthermore, each process (step) indicated by an S number in the flowchart of Fig. 5 is realized by the main control unit 101 and the sub-control unit 102 executing a predetermined program to control the operation of each unit of the electronic device 100. However, predetermined processes among the processes shown in the flowchart of Fig. 5 are executed by predetermined processing units controlled by the main control unit 101 and the sub-control unit 102.

[0046] The processing of S501 is the same as the processing of S301 in the flowchart of Fig. 3, and therefore description thereof will be omitted here. In S502, the sub-control unit 102 determines whether the power control mode to be set later is mode 4, which will be described later. It is assumed that the electronic device 100 is always set to mode 4 when it is first started up after the main battery 120 is attached to the electronic device 100 in a power-off state. If the sub-control unit 102 determines that the power control mode is mode 4 (Yes in S502), the processing proceeds to S503, and if it determines that the power control mode is not mode 4 (No in S502), the processing proceeds to S506.

[0047] The processing of S503 to S505 is the same as the processing of S303 to S305 in the flowchart of Fig. 3, and therefore a description thereof will be omitted. The processing of S506 is the same as the processing of S306 in the flowchart of Fig. 3, and therefore a description thereof will be omitted. In S507, the sub-control unit 102 determines whether the power control mode is mode 1, which will be described later. If the sub-control unit 102 determines that the power control mode is mode 1 (Yes in S507), the processing proceeds to S508, and if the sub-control unit 102 determines that the power control mode is not mode 1 (No in S507), the processing proceeds to S510.

[0048] In S508, the sub-control unit 102 determines whether the power control mode is mode 2, which will be described later. If the sub-control unit 102 determines that the power control mode is mode 2 (Yes in S508), the process proceeds to S509. On the other hand, if the power control mode is not mode 2, the power control mode is set to mode 3, which will be described later, and in mode 3, power is supplied from the power receiving control unit 125 to the first power supply unit 201, so the initial setting performed in S503 is valid. Therefore, if the sub-control unit 102 determines that the power control mode is not mode 2 (No in S508), the process proceeds to S504.

[0049] When the power control mode is set to mode 2, power is supplied from the power receiving control unit 125 to the first power supply unit 201, and power is supplied from the first power supply unit 201 to the second operation control unit 204. Therefore, in S509, the main control unit 101 transitions the system of the electronic device 100 to the power-on mode. Specifically, in S509, the sub-control unit 102 performs initial setup of the main control unit 101, omitting the initial setup process of the first power supply unit 201, and the main control unit 101, after the initial setup, performs initial setup of the first operation control unit 205, omitting the initial setup of the second operation control unit 204. Then, the first operation control unit 205 loads the programs stored in the nonvolatile memory of the storage unit 103 into a volatile storage area inside the first operation control unit 205 and sequentially executes the programs. After the system of the electronic device 100 has started up in this way, the main control unit 101 advances the process to S511.

[0050] If it is determined in S507 that the power supply control mode is mode 1, a predetermined program has already been loaded into a volatile storage area inside the main control unit 101. Therefore, in S510, the main control unit 101 starts up the system of the electronic device 100 by sequentially executing the program loaded into its own volatile storage area. After the system of the electronic device 100 has started up in this way, the main control unit 101 advances the process to S511.

[0051] 3, the processing from S511 to S513 is the same as the processing from S308 to S310 in the flowchart of Fig. 3, and therefore a description thereof will be omitted. In S514, the power reception detection unit 126 detects the power that the power reception control unit 125 can supply and notifies the sub-control unit 102. In the processing from S515 onwards, the sub-control unit 102 determines the power supply control mode according to the power that the power reception control unit 125 can supply and notified by the power reception detection unit 126. Then, the sub-control unit 102 controls the on (closed) / off (open) of the first power supply unit 201 and the switches 206 to 208 according to the determined power control mode.

[0052] 6 is a diagram illustrating power control modes that can be set in the electronic device 100. The power control mode is determined based on the power supply capacity (Pw) of the power receiving control unit 125, the output state of the first power supply unit 201, and the on / off states of the switches 206 to 208. In this embodiment, the power control mode is determined so that the power supply capacity of the power receiving control unit 125 does not exceed the operating power of the connected device in power-off mode.

[0053] The processing from S515 onwards will be described with reference to Fig. 6. For ease of explanation, in the following description, 100 mW is set as the first threshold, 10 mW as the second threshold, and 1 mW as the third threshold for the available power supply Pw of the power receiving control unit 125. However, the values ​​of the first to third thresholds are not limited to these, and appropriate values ​​are determined according to the power required to hold information in the volatile storage areas of the main control unit 101, the power supply control unit 124, and the storage unit 103.

[0054] In S515, the sub-control unit 102 determines whether the suppliable power Pw of the power reception control unit 125 notified by the power reception detection unit 126 is equal to or greater than the first threshold (Pw≧100 mW). If the sub-control unit 102 determines that Pw≧100 mW (Yes in S515), the process proceeds to S516, and if it determines that Pw<100 mW (No in S515), the process proceeds to S517.

[0055] In S516, the sub-control unit 102 sets mode 1, which allows power to be supplied to all of the first power supply unit 201, second operation control unit 204, first operation control unit 205, and memory unit 103 in power-off mode, and then proceeds to S522.

[0056] In S517, the sub-control unit 102 determines whether the suppliable power Pw of the power receiving control unit 125 is equal to or greater than the second threshold and less than the first threshold (10 mW≦Pw<100 mW). If the sub-control unit 102 determines that 10 mW≦Pw<100 mW is satisfied (Yes in S517), the process proceeds to S518, and if the sub-control unit 102 determines that Pw<10 mW is satisfied (No in S517), the process proceeds to S519.

[0057] In S518, the sub-control unit 102 sets the mode to mode 2, which can supply power to two blocks: the first power supply unit 201 and the second operation control unit 204, which requires less operating power in power-off mode than the first operation control unit 205 and the memory unit 103, and then proceeds to S522. Note that power supply to the first operation control unit 205 and the memory unit 103 is stopped by turning off switches 207 and 208.

[0058] In S519, the sub-control unit 102 determines whether the suppliable power Pw of the power receiving control unit 125 is equal to or greater than the third threshold and less than the second threshold (1 mW≦Pw<10 mW). If the sub-control unit 102 determines that 1 mW≦Pw<10 mW (Yes in S519), the process proceeds to S520, and if the sub-control unit 102 determines that Pw<1 mW (No in S519), the process proceeds to S520.

[0059] In S520, the sub-control unit 102 sets the mode to mode 3, which allows power to be supplied only to the first power supply unit 201, and then proceeds to S522. Note that power supply to the first operation control unit 205, the second operation control unit 204, and the storage unit 103 is stopped by turning off the switches 206 to 208.

[0060] When the process proceeds to S521, the power supplyable power Pw of the power receiving control unit 125 notified by the power receiving detection unit 126 is less than the third threshold (Pw<1 mW), and the sub-control unit 102 determines that power cannot be supplied from the power receiving control unit 125 to the first power supply unit 201. Therefore, in S521, the sub-control unit 102 sets the mode to mode 4 in which power is not supplied from the power receiving control unit 125 in the power off mode, and then ends this process.

[0061] 3, the sub-control unit 102 determines whether the power reception detection unit 126 has detected that the power supply from the power reception control unit 125 has been cut off. Specifically, the power reception detection unit 126 monitors the output voltage of the power reception control unit 125, and when it detects that the output voltage has become equal to or lower than a predetermined voltage Vlimit (for example, 2 V), it determines that the power supply from the power reception control unit 125 has been cut off. When the sub-control unit 102 determines that the power supply from the power reception control unit 125 has been cut off (Yes in S523), it proceeds to S521, and when it determines that the power supply from the power reception control unit 125 has not been cut off (No in S523), it proceeds to S524.

[0062] In S524, the sub-control unit 102 determines whether the power switch 104 has been operated from off to on. If the sub-control unit 102 determines that the power switch 104 has been operated from off to on (Yes in S524), it ends this processing. This causes the processing to start again from S501. On the other hand, if the sub-control unit 102 determines that the power switch 104 has not been operated from off to off (No in S524), it returns the processing to S523.

[0063] Next, we will explain the effects obtained by processing according to the flowchart in Fig. 5. Figures 7(a), (b), (c), and (d) are diagrams showing the startup times required when starting up the system of electronic device 100 from a state in which mode 4, mode 1, mode 2, or mode 3 is set as the power control mode when electronic device 100 is powered off. The S numbers in Fig. 7 correspond to the S numbers in the flowchart in Fig. 5.

[0064] In the power control according to the second embodiment, when power is supplied from the power receiving control unit 125 to the first power supply unit 201, the power control mode is switched according to the supply capacity of the power receiving control unit 125. This makes it possible to reduce the power consumption of the main battery 120 and shorten the startup time required for the system startup of the electronic device 100 from the power-off mode.

[0065] The effect of shortening the startup time is greater the more devices that are supplied with power from the power receiving control unit 125 even in the power-off mode, and the following relationship holds: startup time T1 in mode 1 < startup time T2 in mode 2 < startup time T3 in mode 3 < startup time T4 in mode 4. Note that startup time T4 in mode 4 is the same as time Ta in FIG. 4(a).

[0066] Furthermore, in the power control according to the second embodiment, the power control mode is set within a range that does not exceed the power supply capacity of the power receiving control unit 125. This makes it possible to prevent the power supply from the power receiving control unit 125 from being unintentionally cut off when the power switch 104 is in the off state. As a result, it is possible to avoid the occurrence of a problem in which the electronic device 100 does not start up normally the next time the power switch 104 is turned on. Furthermore, when the power receiving detection unit 126 detects that the power supply from the power receiving control unit 125 has been cut off while the power switch 104 is in the off state, the power control mode is set to mode 4. This makes it possible to avoid the occurrence of a problem in which the electronic device 100 does not start up normally the next time the power switch 104 is turned on.

[0067] While the present invention has been described in detail above based on preferred embodiments thereof, the present invention is not limited to these specific embodiments, and various forms within the scope of the gist of the present invention are also included in the present invention. Furthermore, each of the above-described embodiments merely represents one embodiment of the present invention, and each embodiment can be combined as appropriate.

[0068] For example, there are known electronic devices that transition from a normal operation mode to a power saving mode (low power consumption mode) after a period of no operation. The power control mode setting method described in the above embodiment can be applied to the transition process from the normal operation mode to the power saving mode of such electronic devices.

[0069] Furthermore, in the above embodiment, the switch 203 is provided between the main battery 120 and the first power supply unit 201, and while power is being supplied from the power receiving control unit 125 to the first power supply unit 201, the switch 203 is turned off to reduce power consumption of the main battery 120. This configuration is not limiting, and for example, if the power consumption of the first power supply unit 201 when the output from the first power supply unit 201 is cut off is sufficiently small, a configuration without providing the switch 203 may be employed. Furthermore, if power is being supplied to the first power supply unit 201 from both the main battery 120 and the power receiving control unit 125, a configuration that enables the supply of power from the power receiving control unit 125 may be employed.

[0070] In the above embodiment, switches 206 to 208 are provided to intentionally cut off the power supply from first power supply unit 201, but this is not limiting, and a configuration to stop the power output of first power supply unit 201 may also be adopted.

[0071] The present invention can also be realized by supplying a program that realizes one or more functions of the above-described embodiments to a system or device via a network or a storage medium, and having one or more processors in the computer of the system or device read and execute the program. It can also be realized by a circuit (e.g., ASIC) that realizes one or more functions. [Explanation of symbols]

[0072] 100 Electronic equipment 101 Main control unit 102 Sub-controller 103 Storage section 120 Main battery 124 Power supply control unit 125 Power receiving control unit

Claims

1. a first control means; second control means; Batteries and power receiving control means for extracting power from radio waves; a power supply control unit that controls the supply of power from the battery or the power receiving control unit to the second control unit, the first control means switches the supply of power to the power supply control means from the battery in a first operation mode in which the electronic device consumes a large amount of power, and from the power receiving control means when the electronic device transitions to a second operation mode in which the power consumption is smaller than that of the first operation mode; the power supply control means and the second control means each have a volatile storage area for storing settings when operating in the first operating mode, In the second operation mode, at least the settings stored in the volatile storage area of ​​the power supply control means are maintained.

2. a first control means; second control means; a storage means; Batteries and power receiving control means for extracting power from radio waves; a power supply control means for controlling the supply of power from the battery or the power receiving control means to the second control means and the storage means; a detection unit that detects the power supplied from the power receiving control unit to the power supply control unit, The electronic device is characterized in that the first control means supplies power to the power supply control means from the battery in a first operating mode in which the electronic device consumes more power, and switches to supply power from the power receiving control means when transitioning to a second operating mode in which the power consumption is lower than that of the first operating mode, and when transitioning from the first operating mode to the second operating mode, determines the destination of the power supply from the power control means depending on the power detected by the detection means.

3. the power supply control means, the second control means, and the storage means each have a volatile storage area for storing settings when operating in the first operating mode; the first control means adopts a first power supply control mode in which power is supplied to the power supply control means, the second control means, and the storage means when the detection means determines that power equal to or greater than a first threshold is supplied from the power receiving control means to the power supply control means; 3. The electronic device according to claim 2, wherein in the second operating mode, settings stored in the volatile storage areas of the power supply control means, the second control means, and the storage means are maintained.

4. The electronic device according to claim 3, characterized in that the startup time when switching from the second operating mode to the first operating mode is shortened compared to the startup time from a state in which power is not supplied to the power supply control means, the second control means, and the storage means by reading out settings stored in the volatile storage areas of each of the power supply control means, the second control means, and the storage means.

5. the first control means adopts a second power supply control mode in which power is supplied to the power supply control means and the second control means when the detection means detects that power less than the first threshold and equal to or greater than a second threshold that is smaller than the first threshold is supplied from the power receiving control means to the power supply control means; 5. The electronic device according to claim 3, wherein in the second operation mode, settings stored in the volatile storage areas of the power supply control unit and the second control unit are maintained.

6. The electronic device according to claim 5, characterized in that the startup time when switching from the second operating mode to the first operating mode is shortened compared to the startup time from a state in which power is not supplied to the power supply control means, the second control means, and the storage means by reading out settings stored in the volatile storage areas of the power supply control means and the second control means.

7. the first control means adopts a third power supply control mode in which power is supplied to the power supply control means when the detection means detects that power less than the second threshold and equal to or greater than a third threshold that is smaller than the second threshold is supplied from the power receiving control means to the power supply control means; 7. The electronic device according to claim 6, wherein in the second operation mode, settings stored in a volatile storage area of ​​the power supply control means are maintained.

8. The electronic device according to claim 6 or 7, characterized in that the startup time when switching from the second operating mode to the first operating mode is shortened compared to the startup time from a state in which power is not supplied to the power control means, the second control means, and the storage means by reading out settings stored in a volatile storage area of ​​the power control means.

9. 9. The electronic device according to claim 7, wherein the first control means employs a fourth power supply control mode in which, when the detection means detects that power less than the third threshold is supplied from the power receiving control means to the power supply control means, the supply of power to the power supply control means is stopped.

10. The second operation mode is executed when the power switch of the electronic device is turned off, 10. The electronic device according to claim 1, wherein the first operation mode is executed when the power switch is on.

11. Power supply and processing means; a power supply control unit that receives power from the power supply and controls the supply of power to the processing unit, The power supply Batteries and power receiving control means for extracting power from radio waves; the power supply control means has a volatile storage area for storing settings when the electronic device operates in a first operation mode with high power consumption, When the electronic device operates in the first operation mode, power is supplied to the power supply control means from the battery, When the electronic device transitions from the first operating mode to a second operating mode that consumes less power than the first operating mode, the settings stored in the volatile memory area are retained by switching power supply from the power receiving control means to the power supply control means, and when the electronic device transitions from the second operating mode to the first operating mode again, the startup time of the power supply control means is shortened because the settings are stored in the volatile memory area.

12. A method for controlling an electronic device, comprising: supplying power from a battery attached to the electronic device to a power supply control means that controls the supply of power to a control means that performs overall control of the electronic device when the electronic device is operated in a first operation mode in which power consumption is high; a step of storing a setting for operating in the first operating mode in a volatile storage area of ​​the power supply control means; and when transitioning from the first operating mode to a second operating mode that consumes less power than the first operating mode, retaining the settings stored in the volatile memory area and switching the power supply to the power control means to be supplied from a power receiving control means that extracts power from radio waves.

13. A program that causes a computer to function as each of the means of the electronic device according to any one of claims 1 to 11.

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