Power supply device, control method, and storage medium

Abstract

The present invention provides a power supply device, a control method, and a storage medium. The power supply device includes a communication unit and a control unit. The control unit controls the communication unit to perform authentication communication with a cable after the cable is connected to the power supply device, and controls the communication unit not to accept requests from an external device connected to the cable during a period until the authentication communication is completed.

Description

Technical Field

[0001] Aspects of the present invention generally relate to a power supply device and a method for controlling the power supply device. Background Art

[0002] Japanese Unexamined Patent Application Publication No. 2018-97643 describes a power supply device that restricts power to be supplied to an external device in the case of a failure in authentication communication with a USB (Universal Serial Bus) cable having a cable authentication chip.

[0003] However, in the case where the power supply device described in Japanese Unexamined Patent Application Publication No. 2018-97643 receives a request from an external device while performing authentication communication with the cable, the power supply device stops the authentication communication and sends a response to the request, and this lengthens the time required for the authentication communication. Summary of the Invention

[0004] According to various embodiments, there is provided a power supply device capable of shortening the time required for authentication communication.

[0005] According to various embodiments, there is provided a power supply device including: a communication unit; and a control unit configured to control the communication unit to perform authentication communication with the cable after the cable is connected to the power supply device, and control the communication unit not to accept a request from an external device connected to the cable during a period until the authentication communication is completed.

[0006] According to various embodiments, there is provided a control method including: a step of controlling a communication unit of a power supply device to perform authentication communication with the cable after the cable is connected to the power supply device; and a step of controlling the communication unit not to accept a request from an external device connected to the cable during a period until the authentication communication is completed.

[0007] A storage medium stores a program for causing a computer to execute a control method, the control method including: a step of controlling a communication unit of a power supply device to perform authentication communication with the cable after the cable is connected to the power supply device; and a step of controlling the communication unit not to accept a request from an external device connected to the cable during a period until the authentication communication is completed.

[0008] Other aspects of the present invention will become apparent from the following description of exemplary embodiments. Brief Description of the Drawings

[0009] Figure 1 is a diagram for showing components of a power supply system according to a first embodiment.

[0010] Figure 2It is a block diagram for showing the components of the electronic device 100.

[0011] Figure 3 It is a block diagram for showing the components of the cable 200.

[0012] Figure 4 It is a block diagram for showing the components of the power supply device 300.

[0013] Figure 5A It is a diagram for showing the device connector 110 and the source connector 301.

[0014] Figure 5B It is a diagram for showing the cable connectors 201 and 202.

[0015] Figure 6 It is a flowchart for showing an example of the process 600 performed by the power supply device 300.

[0016] Figure 7A It is a diagram for explaining an example of the power that can be supplied from the power supply device 300 to the electronic device 100.

[0017] Figure 7B It is a diagram for explaining an example of the characteristics of the cable 200.

[0018] Figure 7C It is a diagram for explaining an example of the first power supply capacity.

[0019] Figure 7D It is a diagram for explaining an example of the second power supply capacity. Detailed Description

[0020] Hereinafter, exemplary embodiments, features, and aspects of the present invention will be described with reference to the accompanying drawings. However, the aspects of the present invention are not limited to the following embodiments.

[0021] [First Embodiment]

[0022] Figure 1 It is a diagram for showing the components of the power supply system according to the first embodiment. Figure 1 The shown power supply system includes an electronic device 100, a cable 200, and a power supply device 300.

[0023] The electronic device 100 is an electronic device capable of receiving power from the power supply device 300. Figure 1In the example, the electronic device 100 is a digital camera. The electronic device 100 includes a device connector 110 for connecting the electronic device 100 to a power supply device 300. The device connector 110 is, for example, a socket conforming to the USB (Universal Serial Bus) Type-C standard. The electronic device 100 is not limited to a digital camera and may be, for example, an information processing device such as a personal computer, a smartphone, or a tablet terminal.

[0024] The cable 200 is a cable that can transmit information, power, and the like. The cable 200 has a cable connector 201 at one end of the cable 200 and a cable connector 202 at the other end of the cable 200. For example, the cable 200 is a USB cable, and the cable connector 201 and the cable connector 202 are each plugs conforming to the USB Type-C standard.

[0025] The power supply device 300 is a power supply device that can supply power to the electronic device 100 as an external device. In Figure 1 the example, the power supply device 300 is an AC adapter that uses an AC (alternating current) power source. The power supply device 300 includes a source connector 301 for connecting the power supply device 300 to the electronic device 100. The source connector 301 is, for example, a socket conforming to the USB Type-C standard. The power supply device 300 is not limited to an AC adapter. For example, the power supply device 300 may be an information processing device such as a personal computer, or may be a mobile battery or the like.

[0026] For example, the cable connector 201 is connected to the device connector 110, and the cable connector 202 is connected to the source connector 301. In this way, the power supply device 300 can supply power from the source connector 301 to the electronic device 100 via the cable 200. Alternatively, the cable connector 202 may be connected to the device connector 110, and the cable connector 201 may be connected to the source connector 301.

[0027] Figure 2 is a block diagram for showing components of the electronic device 100. Figure 5A is a diagram for showing the device connector 110.

[0028] As Figure 5A shown, the device connector 110 has terminals including a VBUS terminal, a CC1 terminal, a CC2 terminal, or a GND terminal, etc. For example, in the device connector 110, the VBUS terminal is a terminal for receiving power. The CC1 terminal and the CC2 terminal are terminals for obtaining information related to the power supply device 300. The GND terminal is a terminal for determining a reference of a signal.

[0029] A pull-down resistor 101 (Rd) compliant with the USB Type-C standard is connected between the CC1 terminal of the device connector 110 and the GND terminal of the device connector 110. A pull-down resistor 106 (Rd) compliant with the USB Type-C standard is connected between the CC2 terminal of the device connector 110 and the GND terminal of the device connector 110. The pull-down resistors 101 (Rd) and 106 (Rd) are used, for example, to determine whether the power supply device 300 is connected to the electronic device 100 and to determine the voltage supplied from the power supply device 300 to the electronic device 100.

[0030] The communication unit 102 is connected to the CC1 terminal and the CC2 terminal of the device connector 110, and communicates with the cable 200 or the power supply device 300 via the CC1 terminal and the CC2 terminal. For example, the communication unit 102 communicates with the power supply device 300 based on the USB PD (Power Delivery) standard and determines whether the power supply device 300 complies with the USB PD standard. When the power supply device 300 complies with the USB PD standard, the communication unit 102 performs negotiation communication compliant with the USB PD standard with the power supply device 300 to request the power supply device 300 to supply desired power. In addition, the communication unit 102 performs authentication communication compliant with the USB Type-C AUTH (Authentication) standard with the cable 200.

[0031] The cable authentication determination unit 103 determines whether the cable 200 complies with the USB PD standard based on the result of the authentication communication of the communication unit 102.

[0032] The power receiving unit 104 is connected to the VBUS terminal of the device connector 110, and supplies the power supplied from the power supply device 300 to the components of the electronic device 100 via the cable 200. The power receiving unit 104 controls the power supplied from the power supply device 300 based on the result of the communication performed by the communication unit 102.

[0033] The load unit 105 is composed of various modules that operate by consuming the power supplied from the power receiving unit 104. For example, when the electronic device 100 is a digital camera, the load unit 105 includes a camera lens, an imaging element, a display unit, or a user interface unit, etc. For example, the camera lens changes the zoom ratio of the subject image and adjusts the focus of the subject image. The imaging element is an image sensor composed of, for example, a CCD (Charge Coupled Device) or a CMOS (Complementary Metal Oxide Semiconductor), and converts the subject image into electrical image information. The display unit is, for example, an LCD (Liquid Crystal Display), and displays the acquired image information, etc. The user interface unit includes switches, etc., and receives instructions from the user to the electronic device 100. The power consumed by the load unit 105 varies according to the operating state of the electronic device 100.

[0034] Figure 3 It is a block diagram showing components of the cable 200. Figure 5B It is a diagram showing the cable connectors 201 and 202.

[0035] As Figure 5B shown, each of the cable connector 201 and the cable connector 202 has terminals (pins) including a VBUS terminal, a CC terminal, a VCONN terminal, and a GND terminal. For example, in each of the cable connector 201 and the cable connector 202, the VBUS terminal is a terminal for transmitting power, and the CC terminal is a terminal for transmitting various information such as information related to the power supply device 300. The VCONN terminal is a terminal for supplying power to the communication unit 203, and the GND terminal is a terminal for determining a reference of a signal.

[0036] The communication unit 203 is connected to the CC terminal of the cable connector 201, the VCONN terminal of the cable connector 201, the CC terminal of the cable connector 202, and the VCONN terminal of the cable connector 202. The communication unit 203 uses these terminals to communicate with the electronic device 100 or the power supply device 300. For example, the communication unit 203 performs negotiation communication compliant with the USB PD standard with at least one of the electronic device 100 and the power supply device 300. Through this negotiation communication, the communication unit 203 sends characteristic information indicating the characteristics of the cable 200 to at least one of the electronic device 100 and the power supply device 300. Figure 7B It is a diagram for explaining an example of the characteristics of the cable 200, and shows the upper limit of the voltage allowed for the cable 200 (e.g., 20V) and the upper limit of the current allowed for the cable 200 (e.g., 3A). The above characteristic information is, for example, information indicating Figure 7B the characteristics in. The electronic device 100 and the power supply device 300 each perform authentication communication compliant with the USB Type-C AUTH standard with the communication unit 203, and determine whether the cable 200 complies with the USB PD standard.

[0037] A pull-down resistor 204 (Ra) compliant with the USB Type-C standard is connected between the VCONN terminal and the GND terminal of the cable connector 202. A pull-down resistor 205 (Ra) compliant with the USB Type-C standard is connected between the VCONN terminal and the GND terminal of the cable connector 201. The pull-down resistors 204 (Ra) and 205 (Ra) are used, for example, to determine whether the cable 200 is connected to the power supply device 300.

[0038] The reverse current prevention diode 206 is a diode for preventing the power supplied from the VCONN terminal of the cable connector 201 from being supplied to the VCONN terminal of the cable connector 202. The reverse current prevention diode 207 is a diode for preventing the power supplied from the VCONN terminal of the cable connector 202 from being supplied to the VCONN terminal of the cable connector 201.

[0039] Figure 4 is a block diagram for showing components of the power supply device 300. Figure 5A is a diagram for showing the source connector 301.

[0040] As Figure 5A shown, the source connector 301 has terminals (pins; interfaces) including a VBUS terminal, a CC1 terminal, a CC2 terminal, or a GND terminal, etc. For example, in the source connector 301, the VBUS terminal is a terminal for receiving power. The CC1 terminal and the CC2 terminal are terminals for outputting information related to the power supply device 300. The GND terminal is a terminal for determining a reference of a signal. In the case of being connected to the VCONN terminal of the cable 200, each of the CC1 terminal and the CC2 terminal can supply power to the VCONN terminal.

[0041] The connection unit 302 is connected to an external power supply such as an AC power supply or a battery, and obtains power from the external power supply.

[0042] The power control unit 303 converts the power obtained from the connection unit 302 into power that can be supplied from the power supply device 300 to the electronic device 100. The power that can be supplied from the power supply device 300 to the electronic device 100 varies according to the external power supply to which the connection unit 302 is connected. Here, a case will be considered where the connection unit 302 is connected to an AC power supply such as a household power outlet (for example, an AC power supply of 100V and 50Hz) and the power supply device 300 supplies a current of 3A to the electronic device 100 at a DC (direct current) voltage of 9V. In this case, the power control unit 303 performs AC / DC conversion on the power obtained from the connection unit 302 so that power having a DC voltage of 9V and a current of 3A can be supplied to the electronic device 100. The power control unit 303 also generates the power supplied from the power supply device 300 to the VCONN terminal of the cable 200.

[0043] The system control unit 304 controls components of the power supply device 300. For example, based on the result of the authentication communication performed by the communication unit 306, the system control unit 304 selects a first power supply capability or a second power supply capability to notify the electronic device 100 of at least one type of power that can be supplied from the power supply device 300 to the electronic device 100. Figure 7AFIG. is a diagram for explaining an example of power that can be supplied from a power supply device 300 to an electronic device 100. The system control unit 304 controls the power supplied from the power supply device 300 to the electronic device 100 by controlling the power supply control unit 303 based on the result of communication performed by the communication unit 306.

[0044] The output control unit 305 is connected to the VBUS terminal of the power supply control unit 303 and the source connector 301. The output control unit 305 can supply the power supplied from the power supply control unit 303 to the electronic device 100 via the VBUS terminal of the source connector 301 and the cable 200. The output control unit 305 can also stop the power supply to the electronic device 100. For example, the system control unit 304 controls the timing of power supply of the output control unit 305 by controlling the output control unit 305 via the communication unit 306. The system control unit 304 controls the output control unit 305 to stop the power supply of the output control unit 305 in response to receiving a power supply stop command from the electronic device 100. The output control unit 305 is also connected to the switch 319 and the switch 320, and can supply power to at least one of the switch 319 and the switch 320 to be supplied to the VCONN terminal of the cable 200. The output control unit 305 can also stop the power supply to the switch 319 or stop the power supply to the switch 320.

[0045] The communication unit 306 is connected to the CC1 terminal and the CC2 terminal of the source connector 301, and communicates with the cable 200 or the electronic device 100 via the CC1 terminal and the CC2 terminal. For example, the communication unit 306 communicates with the electronic device 100 in accordance with the USB PD standard and determines whether the electronic device 100 conforms to the USB PD standard. The communication unit 306 communicates with the cable 200 in accordance with the USB PD standard and determines whether the cable 200 conforms to the USB PD standard.

[0046] When the electronic device 100 conforms to the USB PD standard, the communication unit 306 performs negotiation communication conforming to the USB PD standard with the electronic device 100. Through this negotiation communication, the communication unit 306 sends power supply capability information indicating a first power supply capability or a second power supply capability to the electronic device 100 to notify the electronic device 100 of at least one type of power that can be supplied from the power supply device 300 to the electronic device 100. In addition, the communication unit 306 performs authentication communication conforming to the USB Type-C AUTH standard with the electronic device 100. Based on this authentication communication, the communication unit 306 notifies the electronic device 100 that the power supply device 300 conforms to the USB PD standard.

[0047] When the cable 200 complies with the USB PD standard, the communication unit 306 performs negotiation communication compliant with the USB PD standard with the communication unit 203 of the cable 200 and obtains characteristic information related to the cable 200. In addition, the communication unit 306 performs authentication communication compliant with USB Type-C AUTH with the cable 200. Then, based on the result of the authentication communication with the cable 200, the system control unit 304 determines whether the cable 200 complies with the USB PD standard.

[0048] The pull-up resistor 307 (Rpa) is connected between the output control unit 305 and the switch 308. The pull-up resistor 307 (Rpa) is a resistor compliant with the USB Type-C standard and has, for example, a resistance value indicating that 3A of power can be supplied.

[0049] The switch 308 is connected between the pull-up resistor 307 (Rpa) and the CC2 terminal of the source connector 301. The system control unit 304 can switch the state of the switch 308 between the conducting state and the non-conducting state by using the control signal EN_Rpa 2. When the state of the switch 308 is in the conducting state, the pull-up resistor 307 (Rpa) is effective.

[0050] The pull-up resistor 309 (Rpb) is connected between the output control unit 305 and the switch 310. The pull-up resistor 309 (Rpb) is a resistor compliant with the USB Type-C standard and has, for example, a resistance value indicating that 1.5A of power can be supplied.

[0051] The switch 310 is connected between the pull-up resistor 309 (Rpb) and the CC2 terminal of the source connector 301. The system control unit 304 can switch the state of the switch 310 between the conducting state and the non-conducting state by using the control signal EN_Rpb 2. When the state of the switch 310 is in the conducting state, the pull-up resistor 309 (Rpb) is effective.

[0052] The switch 311 is connected between the CC2 terminal of the source connector 301 and the pull-down resistor 312 (Rd). The system control unit 304 can switch the state of the switch 311 between the conducting state and the non-conducting state by using the control signal EN_Rpd 2. When the state of the switch 311 is in the conducting state, the pull-down resistor 312 (Rd) is effective.

[0053] The pull-down resistor 312 (Rd) is connected between the switch 311 and the GND terminal of the source connector 301.

[0054] The pull-up resistor 313 (Rpa) is connected between the output control unit 305 and the switch 314. The pull-up resistor 313 (Rpa) is a resistor compliant with the USB Type-C standard and has, for example, a resistance value indicating that 3 A of power can be supplied.

[0055] The switch 314 is connected between the pull-up resistor 313 (Rpa) and the CC1 terminal of the source connector 301. The system control unit 304 can switch the state of the switch 314 between the conducting state and the non-conducting state by using the control signal EN_Rpa 1. When the state of the switch 314 is in the conducting state, the pull-up resistor 313 (Rpa) is effective.

[0056] The pull-up resistor 315 (Rpb) is connected between the output control unit 305 and the switch 316. The pull-up resistor 315 (Rpb) is a resistor compliant with the USB Type-C standard and has, for example, a resistance value indicating that 1.5 A of power can be supplied.

[0057] The switch 316 is connected between the pull-up resistor 315 (Rpb) and the CC1 terminal of the source connector 301. The system control unit 304 can switch the state of the switch 316 between the conducting state and the non-conducting state by using the control signal EN_Rpb 1. When the state of the switch 316 is in the conducting state, the pull-up resistor 315 (Rpb) is effective.

[0058] The switch 317 is connected between the CC1 terminal of the source connector 301 and the pull-down resistor 318 (Rd). The system control unit 304 can switch the state of the switch 317 between the conducting state and the non-conducting state by using the control signal EN_Rd 1. When the state of the switch 317 is in the conducting state, the pull-down resistor 318 (Rd) is effective.

[0059] The pull-down resistor 318 (Rd) is connected between the switch 317 and the GND terminal of the source connector 301.

[0060] The switch 319 is connected between the output control unit 305 and the CC2 terminal of the source connector 301. The system control unit 304 can switch the state of the switch 319 between the conducting state and the non-conducting state by using the control signal EN_VCONN 2. When the VCONN terminal of the cable 200 is connected to the CC2 terminal of the source connector 301, power generated by the power supply control unit 303 is supplied to the VCONN terminal of the cable 200 by bringing the switch 319 into the conducting state.

[0061] The switch 320 is connected between the output control unit 305 and the CC1 terminal of the source connector 301. The system control unit 304 can switch the state of the switch 320 between the conducting state and the non-conducting state by using the control signal EN_VCONN 1. When the VCONN terminal of the cable 200 is connected to the CC1 terminal of the source connector 301, power generated by the power supply control unit 303 is supplied to the VCONN terminal of the cable 200 by bringing the switch 320 into the conducting state.

[0062] The system control unit 304 can control the switches 308, 310, 311, 314, 316, and 317 so that the power supply device 300 operates as a DRP (dual-role port) compliant with the USB PD standard. For example, the system control unit 304 controls the switches 308, 311, 314, and 317 to activate any one of the pull-up resistor 307 (Rpa), the pull-down resistor 312 (Rd), the pull-up resistor 313 (Rpa), and the pull-down resistor 318 (Rd) at a predetermined interval. When the power supply device 300 is connected to the electronic device 100 while the pull-up resistor 307 (Rpa) or 313 (Rpa) is in the active state, the power supply device 300 operates as a source compliant with the USB PD standard. When the power supply device 300 is connected to the electronic device 100 while the pull-down resistor 312 (Rd) or 318 (Rd) is then in the active state, the power supply device 300 operates as a sink compliant with the USB PD standard. By operating the power supply device 300 as a source or a sink, the system control unit 304 can detect the connection between the electronic device 100 and the power supply device 300 even when the electronic device 100 operates as a source, a sink, or a DRP. Therefore, the system control unit 304 can communicate with the electronic device 100 by controlling the communication unit 306. The system control unit 304 can control the switches 308, 310, 311, 314, 316, 317, 319, and 320 by controlling the communication unit 306.

[0063] Figure 6 is a flowchart showing an example of the process 600 performed by the power supply device 300. In the first embodiment, it is assumed that the power supply device 300 is connected to the electronic device 100 via the cable 200.

[0064] In step S601, the system control unit 304 determines whether the power supply device 300 is connected as a source by operating as a DRP. For example, when the connection between the electronic device 100 and the power supply device 300 is detected while the switch 308 or 314 is in the on state, the system control unit 304 determines that the power supply device 300 is connected as a source. When the connection between the electronic device 100 and the power supply device 300 is detected while the switch 311 or 317 is in the on state, the system control unit 304 determines that the power supply device 300 is connected as a sink. For example, the connection between the electronic device 100 and the power supply device 300 can be detected from the voltage level of the CC1 terminal of the source connector 301 or the voltage level of the CC2 terminal of the source connector 301. When the system control unit 304 determines that the power supply device 300 is connected as a source, the system control unit 304 proceeds to step S602, and when the system control unit 304 determines that the power supply device 300 is connected as a sink, the system control unit 304 proceeds to step S607.

[0065] In step S602, the system control unit 304 controls the communication unit 306 to start PD communication with the electronic device 100. PD communication is communication compliant with the USB PD standard. In the first embodiment, the case where the electronic device 100 operates as a sink and the power supply device 300 operates as a source will be described. In addition, in the first embodiment, the case where the CC terminal of the cable 200 is connected to the CC1 terminal of the source connector 301 and the VCONN terminal of the cable 200 is connected to the CC2 terminal of the source connector 301 will be described. After PD communication has started, the system control unit 304 proceeds to step S603.

[0066] In step S603, the system control unit 304 controls the power control unit 303 and the output control unit 305 to start supplying power A to the electronic device 100. For example, power A is the default USB power (5V, 900 mA) compliant with the USB 3.1 standard or the default USB power (5V, 500 mA) compliant with the USB 2.0 standard. After power A has started to be supplied to the electronic device 100, the system control unit 304 proceeds to step S604.

[0067] In steps S604 and S605, the system control unit 304 controls the communication unit 306 not to receive a request (e.g., a request to start authentication communication) from the electronic device 100. Optionally, the processing of step S604 or step S605 can be omitted.

[0068] In step S604, the system control unit 304 controls the communication unit 306 to make the reject / wait response setting of the communication unit 306 effective. The reject / wait response setting is a setting for returning a response indicating rejection of a request or a response indicating standby as a response to a request from the electronic device 100. For example, the reject / wait response setting is a setting for returning a reject message or a wait message as a response to a VCONN_Swap message or a Try.SRC message compliant with the USB PD standard. The VCONN_Swap message and the Try.SRC message are messages for operating the power supply device 300 as a source or a sink. The reject message is a message indicating rejection, and the wait message is a message indicating standby. After the reject / wait response setting of the communication unit 306 becomes effective, the system control unit 304 proceeds to step S605.

[0069] In step S605, the system control unit 304 controls the communication unit 306 to switch the state of the switch 314 to the non-conductive state and switch the state of the switch 316 to the conductive state. This activates the pull-up resistor 315 (Rpb). Accordingly, the voltage level of the CC1 terminal of the source connector 301 changes from the voltage level corresponding to the power supply capacity of 3 A to the voltage level corresponding to the power supply capacity of 1.5 A. In the first embodiment, the voltage level of the CC1 terminal is used to control the communication between the power supply device 300 and the electronic device 100, and indicates whether the communication from the electronic device 100 to the power supply device 300 is restricted. When the voltage level of the CC1 terminal is the voltage level corresponding to the power supply capacity of 1.5 A, communication from the power supply device 300 to the electronic device 100 is permitted, and communication from the electronic device 100 to the power supply device 300 is restricted. When the voltage level of the CC1 terminal is the voltage level corresponding to the power supply capacity of 3 A, communication from the power supply device 300 to the electronic device 100 is restricted, and communication from the electronic device 100 to the power supply device 300 is permitted. In step S605, since the voltage level of the CC1 terminal is changed to the voltage level indicating restriction of communication from the electronic device 100 to the power supply device 300, communication from the electronic device 100 to the power supply device 300 is restricted. After restricting the communication from the electronic device 100 to the power supply device 300, the system control unit 304 proceeds to step S606.

[0070] In step S606, the system control unit 304 controls the communication unit 306 to switch the state of the switch 319 to the conductive state. This supplies power from the CC2 terminal of the source connector 301 to the communication unit 203 of the cable 200 via the VCONN terminal of the cable 200, thereby allowing the communication unit 203 to operate. After starting the power supply to the VCONN terminal of the cable 200, the system control unit 304 proceeds to step S613.

[0071] In step S607, the system control unit 304 controls the communication unit 306 to start PD communication with the electronic device 100. In the first embodiment, the electronic device 100 operates as a source, and the power supply device 300 operates as a sink. After PD communication has been started, the system control unit 304 proceeds to step S608.

[0072] In step S608, the system control unit 304 receives power A from the electronic device 100. After power reception from the electronic device 100 has been started, the system control unit 304 proceeds to step S609.

[0073] In step S609, the system control unit 304 controls the communication unit 306 to send a function change request to the electronic device 100. The function change request is, for example, a VCONN_Swap message compliant with the USB PD standard or a Try.SRC message compliant with the USB PD standard. After the function change request has been sent to the electronic device 100, the system control unit 304 proceeds to step S610.

[0074] In step S610, the system control unit 304 determines whether the electronic device 100 has accepted the function change request sent in step S609. For example, when the system control unit 304 receives an acceptance message compliant with the USB PD standard as a response to the function change request, the system control unit 304 determines that the electronic device 100 has accepted the function change request. When the system control unit 304 does not receive the acceptance message, the system control unit 304 determines that the electronic device 100 has not accepted the function change request. When the system control unit 304 determines that the electronic device 100 has accepted the function change request, the system control unit 304 performs predetermined processing compliant with the USB PD standard. This enables the power supply device 300 to operate as a sink or a source. Then, the system control unit 304 proceeds to step S604. When the system control unit 304 determines that the electronic device 100 has not accepted the function change request, the system control unit 304 proceeds to step S611.

[0075] In step S611, the system control unit 304 increments the value of the count n by 1. After the value of the count n has been incremented by 1, the system control unit 304 proceeds to step S612.

[0076] In step S612, the system control unit 304 determines whether the value of the count n has reached a predetermined value. The predetermined value is, for example, 3. When the system control unit 304 determines that the value of the count n has reached the predetermined value, the system control unit 304 performs timeout processing. In the timeout processing, the system control unit 304 switches the connection between the power supply device 300 and the electronic device 100 from a connection compliant with the USB PD standard to a connection compliant with the USB Type-C standard, and ends Figure 6 the processing 600 in

[0077] In step S613, the system control unit 304 controls the communication unit 306 to perform authentication communication compliant with the USB Type-C AUTH standard (USB Type-C authentication standard) with the cable 200. After starting the authentication communication with the cable 200, the system control unit 304 proceeds to step S614.

[0078] In step S614, the system control unit 304 determines whether the authentication communication in step S613 has been completed (succeeded). For example, when the system control unit 304 receives predetermined authentication information based on the communication protocol of the USB Type-C AUTH standard, the system control unit 304 determines that the authentication communication has been completed (succeeded). When the system control unit 304 does not receive the predetermined authentication information, the system control unit 304 determines that the authentication communication has not been completed (succeeded). The predetermined authentication information is, for example, device-specific information (such as XID). When the system control unit 304 determines that the authentication communication has been completed, the system control unit 304 proceeds to step S615, and when the system control unit 304 determines that the authentication communication has not been completed, the system control unit 304 proceeds to step S619.

[0079] In step S619, the system control unit 304 determines whether a predetermined time period has elapsed since the start of authentication communication in step S613. The predetermined time period is a time period that conforms to the USB PD standard, for example, 4.5 seconds. When the system control unit 304 determines that the predetermined time period has elapsed since the start of authentication communication, the system control unit 304 determines that the authentication communication has not been completed (authentication communication failure) and performs timeout processing. For example, when the connection state between the power supply device 300 and the electronic device 100 is a failure, the authentication communication fails. In the timeout processing, the system control unit 304 switches the connection between the power supply device 300 and the electronic device 100 from a connection conforming to the USB PD standard to a connection conforming to the USB Type-C standard and ends Figure 6 processing 600 in. When the system control unit 304 determines that the predetermined time period has not elapsed since the start of authentication communication, the system control unit 304 proceeds to step S614.

[0080] In step S615, the system control unit 304 controls the communication unit 306 to invalidate the reject / wait response setting of the communication unit 306. After the reject / wait response setting of the communication unit 306 is invalidated, the system control unit 304 proceeds to step S616.

[0081] In step S616, the system control unit 304 controls the communication unit 306 to switch the state of the switch 314 to the conducting state and the state of the switch 316 to the non-conducting state. This activates the pull-up resistor 313 (Rpa). Therefore, the voltage level of the CC1 terminal of the source connector 301 changes from the voltage level corresponding to the power supply capacity of 1.5 A to the voltage level corresponding to the power supply capacity of 3 A. Since the voltage level of the CC1 terminal changes to a voltage level indicating permission for communication from the electronic device 100 to the power supply device 300, communication from the electronic device 100 to the power supply device 300 becomes effective. After the restriction on communication from the electronic device 100 to the power supply device 300 is lifted, the system control unit 304 proceeds to step S617.

[0082] In step S617, based on the result of the authentication communication in step S613, the system control unit 304 determines whether the cable 200 complies with the USB PD standard. For example, the power supply device 300 has a storage unit that pre-stores a list including XIDs corresponding to the cables. Next, the system control unit 304 verifies the XID obtained by the authentication communication in step S613 against this list. When the XID obtained by the authentication communication is represented in the list, the system control unit 304 determines that the cable 200 complies with the USB PD standard. When the XID obtained by the authentication communication is not represented in the list, the system control unit 304 determines that the cable 200 does not comply with the USB PD standard. When the system control unit 304 determines that the cable 200 complies with the USB PD standard, the system control unit 304 proceeds to step S618. When the system control unit 304 determines that the cable 200 does not comply with the USB PD standard, the system control unit 304 proceeds to step S620. When the system control unit 304 determines that the cable 200 complies with the USB PD standard, the system control unit 304 controls the communication unit 306 to perform PD communication with the cable 200 and obtain characteristic information related to the cable 200 from the cable 200.

[0083] In step S618, the system control unit 304 determines the first power supply capacity to notify the electronic device 100 of at least one type of power that can be supplied from the power supply device 300 to the electronic device 100. Next, the system control unit 304 controls the communication unit 306 to send power supply capacity information indicating the first power supply capacity to the electronic device 100. For example, the system control unit 304 sends a source capability message storing the power supply capacity information. Figure 7C is a diagram for explaining an example of the first power supply capacity. For example, the first power supply capacity is determined based on the characteristic information related to the cable 200 and includes at least one type of power allowed by the cable 200. In Figure 7C the example shown, the maximum current (3A) included in the first power supply capacity is the same as the upper limit of the current allowed by the cable 200 (e.g., 3A). In addition, in Figure 7C the example shown, the maximum voltage (20V) included in the first power supply capacity is the same as the upper limit of the voltage allowed by the cable 200 (e.g., 20V). The electronic device 100 selects power B from at least one type of power included in the first power supply capacity and requests the power supply device 300 to supply the selected power B. Next, in response to the request from the electronic device 100, the power supply device 300 changes the power supplied to the electronic device 100 from power A to power B. For example, the system control unit 304 controls the power control unit 303 and the output control unit 305 to change the power supplied to the electronic device 100 from power A to power B.

[0084] In step S620, the system control unit 304 determines a second power supply capability to notify the electronic device 100 of at least one type of power that can be supplied from the power supply device 300 to the electronic device 100. Then, the system control unit 304 controls the communication unit 306 to send power supply capability information indicating the second power supply capability to the electronic device 100. For example, the system control unit 304 sends a source capability message storing the power supply capability information. Figure 7D FIG. is a diagram for explaining an example of the second power supply capability. In Figure 7D the example shown, the maximum power (9.9 W) included in the second power supply capability is lower than the maximum power (60 W) included in the first power supply capability. In Figure 7D the example shown, the maximum current (2 A) included in the second power supply capability is lower than the upper limit of the current allowed by the cable 200 (for example, 3 A). Further, in Figure 7D the example shown, the maximum voltage (9 V) included in the second power supply capability is lower than the upper limit of the voltage allowed by the cable 200 (for example, 20 V). The electronic device 100 selects power B from at least one type of power included in the second power supply capability and requests the power supply device 300 to supply the selected power B. Then, in response to the request from the electronic device 100, the power supply device 300 changes the power supplied to the electronic device 100 from power A to power B. For example, the system control unit 304 controls the power control unit 303 and the output control unit 305 to change the power supplied to the electronic device 100 from power A to power B.

[0085] As described above, according to the first embodiment, the power supply device 300 does not accept a request from the electronic device 100 until the authentication communication with the cable 200 is completed. In this way, compared with the response to the request from the electronic device 100, the power supply device 300 can perform the authentication communication with higher priority, so that the authentication communication can be performed in a short time. Therefore, the power supply device 300 can quickly start processing based on the result of the authentication communication and select the first power supply capability or the second power supply capability in a short time.

[0086] In the above example, the electronic device 100 is connected to the power supply device 300 via the cable 200, and the power supply device 300 does not accept requests from the electronic device 100 until the authentication communication with the cable 200 is completed. However, other configurations are also possible. For example, after the electronic device 100 is connected to the power supply device 300, the power supply device 300 can perform authentication communication with the electronic device 100, and the power supply device 300 can not accept requests from the electronic device 100 until the authentication communication with the electronic device 100 is completed. In this case, the electronic device 100 can be connected to the power supply device 300 by wireless communication or the like without using the cable 200.

[0087] [Second Embodiment]

[0088] A personal computer, a microcomputer, a central processing unit (CPU), or a microprocessor can also implement various functions, various processes, or various methods described in the first embodiment by executing a computer program. In the following description, in the second embodiment, the personal computer, the microcomputer, the CPU, or the microprocessor is referred to as "computer X". In the second embodiment, the computer program for controlling computer X and for implementing various functions, various processes, or various methods described in the first embodiment is referred to as "computer program Y".

[0089] Various functions, various processes, or various methods described in the first embodiment are implemented by computer X that executes computer program Y. In this case, computer program Y is supplied to computer X via a computer-readable storage medium. The computer-readable storage medium in the second embodiment includes at least one of a hard disk device, a magnetic storage device, an optical storage device, a magneto-optical storage device, a memory card, a volatile memory, and a non-volatile memory, etc. The computer-readable storage medium in the second embodiment is a non-transitory storage medium.

[0090] Although aspects of the present invention have been described with reference to exemplary embodiments, it should be understood that the aspects of the present invention are not limited to the exemplary embodiments. The scope of the following claims should be given the broadest interpretation to encompass all such modifications and equivalent structures.

Claims

1. A power supply device, comprising: A communication unit; And A control unit configured to control the communication unit to perform authentication communication with the cable after the cable is connected to the power supply device, and to control the communication unit not to accept requests from an external device connected to the cable during a period until the authentication communication is completed. Wherein, the control unit controls the communication unit to send power supply capacity information related to the power supply capacity of the power supply device to the external device via the cable after the authentication communication with the cable is completed, and Wherein, the control unit selects one power supply capacity from a plurality of power supply capacities including a first power supply capacity and a second power supply capacity lower than the first power supply capacity based on the authentication communication, and controls the communication unit to send power supply capacity information indicating the selected power supply capacity to the external device.

2. The power supply device according to claim 1, further comprising an interface for the communication unit to communicate with the external device. Among them, The control unit controls the communication unit to change the voltage level of the interface to a voltage level indicating that communication from the external device to the power supply device is restricted during a period until the authentication communication is completed.

3. The power supply device according to claim 1, wherein, The control unit controls the communication unit to return a response indicating rejection of the request as a response to the request during a period until the authentication communication is completed.

4. The power supply device according to claim 1, wherein The control unit controls the communication unit to return a response indicating standby as a response to the request during a period until the authentication communication is completed.

5. The power supply device according to claim 1, wherein The authentication communication is communication compliant with USB Type-C authentication.

6. The power supply device according to claim 1, wherein In the case where the authentication communication fails to be completed, the control unit switches the connection between the power supply device and the external device to a USB Type-C compliant connection.

7. The power supply device according to claim 1, wherein, The control unit determines whether the cable complies with USB PD, i.e., USB Power Delivery, based on the result of the authentication communication. In the case where the control unit determines that the cable complies with the USB PD, it controls the communication unit to send power supply capacity information indicating the first power supply capacity to the external device, and in the case where the control unit determines that the cable does not comply with the USB PD, it controls the communication unit to send power supply capacity information indicating the second power supply capacity to the external device.

8. A control method, comprising: A step of controlling a communication unit of a power supply device to perform authentication communication with a cable after the cable is connected to the power supply device; A step of controlling the communication unit not to accept requests from an external device connected to the cable during a period until the authentication communication is completed; A step of controlling the communication unit to send power supply capacity information related to the power supply capacity of the power supply device to the external device via the cable after the authentication communication with the cable is completed; And A step of selecting one power supply capacity from a plurality of power supply capacities including a first power supply capacity and a second power supply capacity lower than the first power supply capacity based on the authentication communication, and controlling the communication unit to send power supply capacity information indicating the selected power supply capacity to the external device.

9. A storage medium storing a program for causing a computer to execute a control method, the control method including: A step of controlling a communication unit of a power supply device to perform authentication communication with the cable after the cable is connected to the power supply device; A step of controlling the communication unit not to accept requests from an external device connected to the cable during a period until the authentication communication is completed; A step of controlling the communication unit to send power supply capacity information related to the power supply capacity of the power supply device to the external device via the cable after the authentication communication with the cable is completed; And A step of selecting one power supply capacity from a plurality of power supply capacities including a first power supply capacity and a second power supply capacity lower than the first power supply capacity based on the authentication communication, and controlling the communication unit to send power supply capacity information indicating the selected power supply capacity to the external device.

10. A computer program product including a computer program which, when executed by a processor, implements the steps of the control method according to claim 8.

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