JP2016218972A - USB hub device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a USB hub device that functions as a USB hub and can supply electric power for charging tablet equipment, etc., when the equipment is connected by controlling a direction of electric power supply.SOLUTION: The present invention relates to a USB hub device which comprises a plurality of USB connectors and is connected to terminals through the connectors respectively, the USB device being configured to receive an instruction for switching from a user and to mutually switch a host mode and a device mode on receiving the instruction for switching to make connections with terminals.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a USB hub device.

  In recent years, devices that place importance on portability such as tablet devices have been widely used. Such a device is operated by a battery, and the battery is charged by receiving power from the outside. Here, a USB terminal is widely used as a terminal for receiving external power supply.

  On the other hand, the number of USB terminals included in such a tablet device is limited due to its size and the like, and a USB hub is used when a keyboard and other devices are connected to the USB terminal. That is, a USB hub is connected to the USB terminal of the tablet device, and various devices are connected to the USB hub.

  However, while various devices are connected via a USB hub, the tablet device operates as a USB host, and according to the USB standard, it can supply power to others. It will not be possible to charge the battery of the tablet device in response to the power supply.

JP 2004-104998 A

  Patent Document 1 discloses that one electronic device cannot be set as a charging power supply source or a supply destination depending on the situation, and the cable is not connected by a signal at a predetermined terminal. An example that enables charging is disclosed.

  The present invention has been made in view of the above circumstances, and has a function as a USB hub, and controls the direction of power supply to charge the device when a tablet device or the like is connected. One object of the present invention is to provide a USB hub device that can supply power to the device.

  The present invention that solves the problems of the above-described conventional example is a USB hub device that includes a plurality of USB connectors and is connected to a terminal via each of the connectors, and accepting means for receiving a switching instruction from a user; The accepting means includes a switching means for switching between a host mode that operates as a USB host and a device mode that operates as a USB device in accordance with an accepted switching instruction, and performs connection with the terminal. Is.

  Here, when the switching unit enters the host mode, it starts power supply via the VBUS terminal of the USB connector, and monitors the potential of at least one of the D + terminal and the D− terminal, and determines the result of the monitoring. Accordingly, the power supplied via the VBUS terminal may be controlled.

  Further, the USB connector includes an ID terminal, and the switching means performs switching between the host mode and the device mode by setting the ID terminal to GND (ground level) or high impedance. Also good.

  Further, the USB connector is a type-C connector, and the switching means switches between the host mode and the device mode by controlling a configuration channel terminal of the USB connector. It is good.

  A function as a USB hub is provided, and the power supply direction is controlled, and when a tablet device or the like is connected, power for charging the device can be supplied to the device.

It is a block diagram showing an example of a USB hub device according to an embodiment of the present invention. It is a block diagram showing the example of a functional structure of the USB hub apparatus which concerns on embodiment of this invention. It is a flowchart figure showing the operation example of the USB hub apparatus which concerns on embodiment of this invention. It is a schematic circuit diagram showing an example of a part of a circuit of a USB connector of a USB hub device according to an embodiment of the present invention.

  Embodiments of the present invention will be described with reference to the drawings. As shown in FIG. 1, the USB hub device 10 according to the embodiment of the present invention includes a control unit 11, a storage unit 12, a plurality of USB controller modules 13, a power supply unit 14, and an operation unit 15. ing. The USB controller module 13 includes a USB connector 131 and a USB controller unit 132.

  Hereinafter, an outline of the operation of each unit will be described. The control unit 11 is a program control device such as a CPU, and operates according to a program stored in the storage unit 12. In the present embodiment, the control unit 11 performs an operation in a host mode (mode that operates as a USB host) or a device mode (mode that operates as a USB device) of a USB device. Further, the control unit 11 switches between the host mode and the device mode in accordance with a switching instruction from the user, and performs connection with a USB device (a terminal connected to the USB connector 131 or the like). The specific operation of the control unit 11 will be described in detail later.

  The storage unit 12 is a memory device or the like and holds a program executed by the control unit 11. This program may be provided by being stored in a computer-readable and non-transitory recording medium, and may be stored in the storage unit 12 or from a USB device connected as a host via the USB connector 131. It may be provided and stored in the storage unit 12. In the present embodiment, the storage unit 12 also operates as a work memory of the control unit 11.

  The USB connector 131 of the USB controller module 13 includes at least a power supply terminal VBUS, a pair of data terminals D + and D−, an identification terminal ID (referred to as an ID terminal), and a ground terminal (GND terminal) set to a reference potential. ) GND.

  The USB controller unit 132 controls the state of each terminal included in the USB connector 131 in accordance with an instruction input from the control unit 11. Specifically, the USB controller unit 132 controls the data terminals (D +, D−) included in the USB connector 131 when instructed to send data from the control unit 11, and is instructed by the control unit 11. The transmitted data is transmitted to the USB device connected to the USB connector 131. In this embodiment, the USB controller unit 132 connects the ID terminal of the USB connector 131 to the GND terminal or floats (not connected anywhere) according to an instruction input from the control unit 11. To do.

  The power supply unit 14 receives external power supply. When power supplied from a commercial power source or the like is supplied from the outside, the power supply unit 14 supplies the power to each unit. For example, the power supply to the power supply unit 14 may be performed as a DC power supply via an AC adapter. The operation unit 15 is, for example, a tact switch or the like, and outputs a signal indicating that the operation unit 15 is pressed to the control unit 11 in response to the user's pressing operation.

  Here, the operation of the control unit 11 will be described. As illustrated in FIG. 2, the control unit 11 according to the present embodiment includes a hub function unit 21, a switching instruction receiving unit 22, a mode switching operation unit 23, a device mode function unit 24, and a host mode function unit 25. It is comprised including.

  The hub function unit 21 is mounted by the control unit 11 in software or as a hub IC (Integrated Circuit) (that is, as a hardware independent module). The hub function unit 21 operates as a USB hub function while operating in the device mode. Since the operation of the hub function unit 21 is widely known, a detailed description thereof is omitted here.

  The switching instruction receiving unit 22 receives a switching instruction from the user while the control unit 11 is operating in the device mode. This switching instruction is performed by, for example, a pressing operation of the operation unit 15. In this case, when a signal indicating that the button has been pressed is input from the operation unit 15, the control unit 11 assumes that a switching instruction has been issued and outputs information indicating that to the mode switching operation unit 23. To do.

  The switching instruction receiving unit 22 receives a switching instruction from the user while the control unit 11 is operating in the host mode. This switching instruction may also be performed by a pressing operation of the operation unit 15. In the case of this example, when the control unit 11 receives a signal indicating that it has been pressed from the operation unit 15, it is assumed that there is a switching instruction, and the mode switching operation unit 23 displays information indicating that. Output to.

  The mode switching operation unit 23 is information indicating that a switching instruction is received from the switching instruction receiving unit 22 when the control unit 11 is operating in the device mode (when the device mode function unit 24 is operating). Is input, the USB controller unit 132 of each USB controller module 13 is instructed to change the state of the ID terminal of the USB connector 131. Here, the mode switching operation unit 23 instructs the USB controller unit 132 to disconnect the ID terminal from the GND terminal to be in a floating state (to be in a high impedance state). The mode switching operation unit 23 functionally stops the hub function unit 21 (when the hub function unit 21 is mounted as a hardware independent module, the power supply to the module is cut off). Alternatively, the device mode function unit 24 is instructed to stop the operation, and the host mode function unit 25 is instructed to start the operation. At this time, the mode switching operation unit 23 may execute a host exchange procedure (HNP).

  Further, the mode switching operation unit 23 indicates that a switching instruction has been received from the switching instruction receiving unit 22 when the control unit 11 is operating in the host mode (when the host mode function unit 25 is operating). When the information to be expressed is input, the USB controller unit 132 of each USB controller module 13 is instructed to change the state of the ID terminal of the USB connector 131. Here, the mode switching operation unit 23 instructs the USB controller unit 132 to connect the ID terminal to the GND terminal. Then, the mode switching operation unit 23 executes a session request procedure (SRP), and further starts the operation of the hub function unit 21 (when the hub function unit 21 is implemented as a hardware independent module, The power supply to the module may be started). The mode switching operation unit 23 instructs the host mode function unit 25 to stop the operation, and instructs the device mode function unit 24 to start the operation.

  When the operation starts, the device mode function unit 24 recognizes a USB device connected to any USB controller module 13 as a host. In the present embodiment, the control unit 11 performs this recognition by referring to the state of the ID terminal. Specifically, if a USB device whose ID terminal is not electrically connected to another terminal (in a float state) is connected, the control unit 11 recognizes the USB device as a host. The device mode function unit 24 of each USB controller module 13 turns off the VBUS of the USB connector 131 of each USB controller module 13 (cuts off the power supply from the power supply unit 14 via the VBUS terminal). Instructs the USB controller unit 132. The USB controller unit 132 of each USB controller module 13 electrically disconnects the VBUS of the USB connector 131 from the power supply unit 14 in accordance with the instruction of the control unit 11.

  In addition, when the USB device is connected to the USB controller module 13 during operation, the device mode function unit 24 detects the connection of the USB device and connects the USB device to the hub function unit 21 ( It operates to output data input from the USB device to the hub function unit 21).

  When the host mode function unit 25 starts operating, each USB controller module supplies power supplied from the power supply unit 14 via the VBUS terminal of the USB connector 131 of each USB controller module 13 (VBUS is turned on). 13 USB controller units 132 are instructed. The USB controller unit 132 of each USB controller module 13 starts supplying power by turning on the VBUS of the USB connector 131 in accordance with the instruction from the control unit 11. In response to a request from a USB device connected to the USB controller module 13, the amount of power supplied to the USB device via the VBUS terminal is controlled. By the operation of the host mode function unit 25, the control unit 11 does not operate as a hub function while operating in the host mode, and the USB device connected via the USB connector 131 is connected to the charger. Behave as if they are connected.

  The USB hub device 10 of the present embodiment basically has the above configuration and operates as follows. In the following example, a case where a battery-driven terminal 20 that can operate as a USB host is connected will be described as an example. Here, it is assumed that the terminal 20 operates with a rechargeable battery. The terminal 20 can be connected via a USB terminal. When the USB terminal is connected to the USB hub device 10, the terminal 20 functions as a host, and other devices connected via the USB hub device 10, For example, an operation of acquiring data from a camera or the like is performed. Further, when the terminal 20 recognizes that the charger is connected via the USB terminal, the terminal 20 charges the battery using the power supplied via the USB terminal.

  The USB hub device 10 operates as illustrated in FIG. 3 when such a terminal 20 is connected, and recognizes the terminal 20 as a host and functions as a hub while functioning as a device mode (S1). Perform the operation. While functioning as a device mode, the USB hub device 10 repeatedly checks whether or not a switching instruction has been received from the user (S2). If there is no switching instruction (if No), the USB hub apparatus 10 performs processing S1 (device). Operation as a mode).

  If the USB hub device 10 determines in step S2 that there has been a switching instruction from the user (Yes), the USB hub 131 disconnects the ID terminal of the USB connector 131 of each USB controller module 13 from the GND terminal. (High impedance state) (S3). The USB hub device 10 stops functioning as a hub (S4), turns on the VBUS of the USB connector 131, and starts supplying power to the terminal 20 (S5).

  The terminal 20 recognizes that the charger is connected to the USB terminal when, for example, VBUS is turned on, or the host terminal is connected to the USB terminal because the ID terminal is high impedance. The battery is charged using the power supplied via the VBUS terminal of the USB terminal.

  As described above, according to the present embodiment, a function as a USB hub is provided, and the direction of power supply is controlled to charge the terminal 20 when the terminal 20 such as a tablet device is connected. Electric power can be supplied to the device. One of the characteristic features of the present embodiment is that when the USB hub device 10 of the present embodiment operates in the host mode, the terminal 20 recognizes the USB hub device 10 as a charger. It is possible to perform charging by receiving power supply from the USB hub device 10 without complying with the ACA (Accessory Charger Adapter) standard or the like.

  As a result, the USB hub device 10 operates in the host mode. Then, the USB hub device 10 repeatedly checks whether or not there has been a switching instruction from the user (S6). If there is no switching instruction (if No), the operation of the processing S6 (operation as the host mode) is performed. to continue.

  If the USB hub device 10 determines in step S6 that there is a switching instruction from the user (Yes), the USB hub device 10 connects the ID terminal of the USB connector 131 of each USB controller module 13 to the GND terminal (S7). . The USB hub device 10 starts the function as a hub (S8), turns off the VBUS of the USB connector 131, and stops the supply of power to the terminal 20 (S9). Further, the USB hub device 10 executes a session request procedure (SRP) and requests the terminal 20 to connect as a device (S10). Then, the USB hub device 10 returns to the process S1 and continues the operation as the device mode.

[Quick charge]
Further, in an example of the present embodiment, the host mode function unit 25 of the USB hub device 10 monitors the potential of at least one of the data terminals D + and D− of the USB connector 131 during operation, and according to the result of the monitoring. The power supplied via the VBUS terminal may be controlled.

  Specifically, in this example, quick charging according to the Quick Charge 2.0 protocol defined by Qualcomm is supported. That is, after turning on VBUS, the host mode function unit 25 monitors the potential of the D + terminal among the data terminals (potential difference from the potential of the GND terminal). At this time, when the potential of the D + terminal is 0.325 V for a predetermined time (for example, 1.25 seconds) or longer, the host mode function unit 25 shifts to the quick charge mode.

  In the quick charge mode, the host mode function unit 25 monitors the potential of the D− terminal among the data terminals (potential difference from the potential of the GND terminal). When the potential of the D- terminal becomes less than 0.325 V for a predetermined time (for example, 1 millisecond) or more, the potential of the data terminals D + and D- is referred to, and the potential of the D- terminal is next 0.325 V or more The power of the voltage corresponding to the potential of the D + and D− terminals at that time is supplied via the VBUS terminal. Since the voltage (required voltage) to be supplied here is determined in the quick charge protocol according to the potentials of the D + and D− terminals, detailed description thereof is omitted here.

  In another example of the present embodiment, the host mode function unit 25 may set the D + and D− terminals to the same potential (assuming they are short-circuited).

[Example of USB TypeC connector]
In one example of the present embodiment, the USB connector 131 may be a type C (Type-C) connector. The control unit 11 of the present embodiment when using a type C connector has the same configuration as illustrated in FIG. 2, but the operation of the mode switching operation unit 23 is slightly different. That is, the mode switching operation unit 23 according to this example switches between the host mode and the device mode by controlling the configuration channel terminal of the USB connector 131.

  Specifically, in this example of the present embodiment, the configuration channel terminal (CC1, CC2 terminal) portion of the USB connector 131 includes a circuit whose outline is shown in FIG. As illustrated in FIG. 4, the circuit of the CC1 and CC2 terminals of the USB connector 131 according to this example of the present embodiment includes a first switch 135, a second switch 136, and resistors Ra and Rd. Configured. Here, the first switch 135 has terminals A, B, and P, and electrically connects either the terminal A or the terminal B and the terminal P in accordance with an instruction input from the USB controller unit 132. The second switch 136 has terminals C, D, and Q, respectively, and includes two switches 136a and 136b that are linked. The second switches 136a and 136b are linked to each other and electrically connect either the terminal C or the terminal D and the terminal Q in accordance with an instruction input from the USB controller unit 132.

  Here, the terminal P of the first switch 135 is connected to the CC2 terminal, and the terminal A is connected to the terminal Q of the second switch 136. The terminal B of the first switch 135 is connected to GND (the same potential as the GND terminal) via the resistor Ra.

  The terminals C of the second switches 136a and 136b are both open (open), the terminals D are connected to each other, and both are connected to the GND via the resistor Rd.

  The mode switching operation unit 23 of the control unit 11 according to the present embodiment switches from the switching instruction receiving unit 22 when the control unit 11 is operating in the device mode (when the device mode function unit 24 is operating). If there is an input of information indicating that there is an instruction, the USB controller unit 132 of each USB controller module 13 is instructed to change the state of the configuration channel terminals (CC1, CC2 terminals) of the USB connector 131. To do. Here, the mode switching operation unit 23 instructs the USB controller unit 132 to once open both the CC1 and CC2 terminals, and then pulls down one of them with the resistance value Ra. The mode switching operation unit 23 functionally stops the hub function unit 21 (when the hub function unit 21 is mounted as a hardware independent module, the power supply to the module is cut off). Alternatively, the device mode function unit 24 is instructed to stop the operation, and the host mode function unit 25 is instructed to start the operation. At this time, the mode switching operation unit 23 may execute a host exchange procedure (HNP).

  Further, the mode switching operation unit 23 indicates that a switching instruction has been received from the switching instruction receiving unit 22 when the control unit 11 is operating in the host mode (when the host mode function unit 25 is operating). When the information to be expressed is input, the USB controller unit 132 of each USB controller module 13 is instructed to change the state of the configuration channel terminals (CC1, CC2 terminals) of the USB connector 131. Here, the mode switching operation unit 23 instructs the USB controller unit 132 to once open both the CC1 and CC2 terminals, and then pulls down one of them with the resistance value Ra and the other as the resistance. Instruct to pull down with the value Rd.

  The mode switching operation unit 23 executes a session request procedure (SRP) and further starts the operation of the hub function unit 21 (if the hub function unit 21 is mounted as a hardware independent module, the module It is also possible to start power supply to The mode switching operation unit 23 instructs the host mode function unit 25 to stop the operation, and instructs the device mode function unit 24 to start the operation.

  In this example of the present embodiment, the device mode function unit 24 recognizes the USB device serving as the host based on the state of the CC1 and CC2 terminals. This method conforms to the type C USB connector 131 standard. Since it is as defined, a detailed description thereof is omitted here.

In the present embodiment, the USB controller unit 132 operates as follows in response to an instruction input from the mode switching operation unit 23 described above. Specifically, the USB controller unit 132
(1) When there is an instruction to open both the CC1 and CC2 terminals, the terminal P of the first switch 135 connected to the CC2 terminal is controlled to be connected to the terminal A, and the CC1 terminal and the CC2 terminal are controlled. Control is performed so that the terminal Q of the second switches 136a and 136b connected to the terminal A of the terminal is connected to the terminal C. Thereby, both CC1 and CC2 terminals will be in an open state.
(2) When there is an instruction to pull down one of the CC1 and CC2 terminals with the resistance value Ra, control is performed so that the terminal P of the first switch 135 connected to the CC2 terminal is connected to the terminal B, and CC1 Control is performed so that the second switch 136a connected to the terminal and the terminal Q of the second switch 136b connected to the terminal A of the CC2 terminal are connected to the terminal C, respectively. As a result, the CC1 terminal is opened, and the CC2 terminal is pulled down with the resistance value Ra.
(3) When instructed to pull down one of the CC1 and CC2 terminals with the resistance value Ra and pull down the other with the resistance value Rd, the terminal P of the first switch 135 connected to the CC2 terminal is connected to the terminal B. And the terminals Q of the second switches 136a and 136b connected to the terminal A of the CC1 terminal and the CC2 terminal are controlled to be connected to the terminal D. As a result, the CC1 terminal is pulled down with the resistance value Rd, and the CC2 terminal is pulled down with the resistance value Ra.

  According to the type C standard, in the terminal 20 connected to the type C USB connector 131 via the USB cable, when both the CC1 and CC2 terminals are in the open state, the connection is recognized as disconnected. Will be. Further, when one of the CC1 and CC2 terminals is pulled down with the resistance value Ra and the other is in an open state, the USB hub device 10 is recognized as a charger. Furthermore, when one of the CC1 and CC2 terminals is pulled down with the resistance value Ra and the other is pulled down with the resistance value Rd, the terminal 20 recognizes the USB hub device 10 as a USB device.

[Another example of switching instructions]
In the above description of the present embodiment, the USB hub device 10 includes the operation unit 15, and whether to operate in the host mode or the device mode by operating the operation unit 15. However, the present embodiment is not limited to this.

  For example, in the USB hub device 10 of the present embodiment, while operating in the device mode, a switching instruction may be received from the terminal 20 operating as a host connected to any USB connector 131.

  Further, in another example of the present embodiment, the operation unit 15 may include a remote controller receiving unit and a remote controller, and may accept a switching instruction from the remote controller.

[Power supply to the power supply]
In the present embodiment, the power supply unit 14 does not necessarily have to be supplied with commercial power. When commercial power is not supplied to the power supply unit 14, the control unit 11 always operates in the device mode, and operates by receiving power from a USB device connected as a host. In this case, the control unit 11 checks whether or not commercial power is supplied to the power supply unit 14 when receiving a switching instruction while operating in the device mode. If not, the control unit 11 switches to the host mode. Continue in device mode without doing so. If commercial power is supplied to the power supply unit 14, a switching operation to the host mode is performed.

DESCRIPTION OF SYMBOLS 10 USB hub apparatus, 11 Control part, 12 Storage part, 13 USB controller module, 14 Power supply part, 15 Operation part, 20 Terminal, 21 Hub function part, 22 Switching instruction | indication reception part, 23 Mode switching operation part, 24 Device mode function Unit, 25 host mode function unit, 131 USB connector, 132 USB controller unit, 135 first switch, 136 second switch.

Claims (4)

A USB hub device provided with a plurality of USB connectors and connected to a terminal via each of the connectors,
An acceptance means for accepting a switching instruction from the user;
A USB hub apparatus comprising: a host mode that operates as a USB host and a device mode that operates as a USB device and switches between the terminal and the terminal in accordance with a switching instruction received by the receiving unit. . The USB hub device according to claim 1,
The switching unit starts power supply via the VBUS terminal of the USB connector when the host mode is set, and monitors the potential of at least one of the D + terminal and the D− terminal, and the switching unit according to the monitoring result. A USB hub device that controls the power supplied via the VBUS terminal. The USB hub device according to claim 1 or 2,
The USB connector includes an ID terminal,
The switching means is a USB hub device that switches between a host mode and a device mode by setting the ID terminal to GND or high impedance. The USB hub device according to claim 1 or 2, wherein the USB connector is a type C connector,
The USB hub device that performs switching between the host mode and the device mode by controlling the configuration channel terminal of the USB connector.

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