Patent Application
20110131426
This application is based upon and claims the benefit of priority from Japanese Patent Application No. 2009-272632, filed Nov. 30, 2009; the entire contents of which are incorporated herein by reference.
Embodiments described herein relate generally to a power supply technique suitable for, for example, personal computers to receive electric power supplied from an external device connected to a connector thereof, by diverting a power supply line to supply power to the external device connected to the connector.
In recent years, notebook personal computers which can be powered by batteries and are easily portable have become widespread. Computers of this type have been downsized and weights thereof have been reduced, in consideration of easy portability. So, the main body of the computers is equipped with only basic function, and provided with a connector to expand the function to various functions as desired.
For example, a Universal Serial Bus (USB) connector can conduct a power supply line between the computer and an external device connected to the USB connector, and thus can operate the external device by supplying power from the computer to the external device through the USB connector.
In addition, recently, various mechanisms have been proposed to supply power from an external device to the computer through the USB connector conversely from the above case, to charge batteries in the computer (for example, see Jpn. Pat. Appln. KOKAI Pub. No. 2009-151488).
In the meantime, recent computers are equipped with a mechanism which automatically incorporates external devices, which are connected to the computer while the computer is operated, into the system, which is referred to as “Plug and Play” (PnP), as standard mechanism. Therefore, when an external device is connected to the computer while the computer is operated, it is controlled such that power supply from the computer to the external device is automatically started.
Therefore, mechanisms to supply power from an external device through a USB connector, which have been proposed up to now, including Jpn. Pat. Appln. KOKAI Pub. No. 2009-151488 mentioned above, generally perform control to input power from the external device, when the external device including a power supply function is connected to the USB connector when the computer is in a power-off state, to avoid collision between input and output of power. Therefore, in prior art, it is impossible to connect an external device including a power supply function to a USB connector of a computer while the computer is operated, and supply power to the computer from the external device.
A general architecture that implements the various feature of the embodiments will now be described with reference to the drawings. The drawings and the associated descriptions are provided to illustrate the embodiments and not to limit the scope of the invention.
Various embodiments will be described hereinafter with reference to the accompanying drawings.
In general, according to one embodiment, an information processing apparatus includes a connector, a switching module and a controller. The connector is configured to connect an external device. The switching module is configured to switch between output of electric power to a power supply line, which is connected to the connector, and input of electric power from the power supply line. The controller is configured to make the switching module switch to output of electric power to the power supply line and determine whether the external device includes an electric power supply function when the external device is connected to the connector, and to make the switching module switch to input of electric power from the power supply line when the external device includes an electric power supply function.
The external device 2 illustrated in
As illustrated in
The CPU 11 is a processor which manages operation control of the computer 1, and executes various programs loaded into the main memory 12. The various programs include an operating system (OS) 201 which performs resource management of the computer 1, application programs 202 which operate under the control of the OS 201, and drivers 203 to perform operation control for various devices being hardware from software. The application programs 202 include a power management utility program to properly switch input and output of the power (through the USB connector 15) when the solar battery unit 2 is connected to the USB connector 15. In addition, the drivers 203 include a driver for the solar battery unit 2 to drive and control the solar battery unit 2 connected to the USB connector 15.
The chipset 13 is a bridge device which relays reception and transmission of data performed between the CPU 11, the main memory 12 and various devices. A USB data line “a1” which conducts to the external device 2 connected to the USB connector 15 continues to the chipset 13.
The EC 14 is a controller to transmit operations of the keyboard and the pointing device to the CPU 11. The EC 14 includes a function of starting/stopping the computer 1, in response to on/off operations of the power button. In addition, the EC 14 includes an interface to drive and control the input/output control circuit 16.
A USB power supply line “a2” which conducts to the external device 2 connected to the USB connector 15 continues to the input/output control circuit 16. The input/output control circuit 16 is a switching circuit to exclusively perform output of power to the USB power supply line “a2” and input of power from the USB power supply line “a2”.
The USB power supply circuit 17 is a circuit which generates power to be output to the USB power supply line “a2” by using power from the battery 18. The battery 18 is a secondary battery which can be repeatedly charged and discharged. The charge circuit 19 is a circuit which charges the battery 18 by using power input from the USB power supply line “a2”. Power from an external commercial power supply is input to the charge circuit 19 when it is connected with an AC adapter, and the charge circuit 19 can charge the battery 18 by using the power from the external commercial power supply.
On the other hand, the solar battery unit 2 which is connected to the USB connector 15 of the computer 1 including the above structure includes a solar battery panel 21, a battery 22, a USB control circuit 23, and a power feeding circuit 24.
The battery 22 is a secondary battery to store electricity generated by the solar battery panel 21. The power feeding circuit 24 outputs power from the battery 22 to the USB power supply line “a2” conducting to the computer 1, under control by the USB control circuit 23.
The USB control circuit 23 is a circuit which manages operation control of the solar battery unit 2, and includes a function of performing communication with the computer 1 through the USB data line “a1” conducting to the computer 1. By performing communication between the USB control circuit 23 and the computer 1, the solar battery unit 2 can operate as a usual USB device (as viewed from the computer 1).
In addition,
As illustrated in
The bus switch 161 is provided on a power supply line which is laid in the input/output control circuit 16 to lead power generated by the USB power supply circuit 17 to the USB power supply line “a2”, and opens or shut off the power supply line on the basis of a control signal (presence/absence of supply of an enable signal) supplied from the EC 14. The backflow prevention circuit 163 is provided on the output side of the bus switch 161.
In addition, the bus switch 162 is provided on a power supply line which is laid in the input/output control circuit 16 to lead power input from the USB power supply line “a2” to the charge circuit 19, and opens or shut off the power supply line on the basis of a control signal (which is different from the control signal input to the bus switch 161) (presence/absence of supply of an enable signal) supplied from the EC 14. The backflow prevention circuit 164 is provided on the output side of the bus switch 162.
The input/output control circuit 16 forms a path from the USB power supply line “a2” to the charge circuit 19 indicated by an arrow “b2”, while preventing bad influence on the existing path from the USB power supply circuit 17 to the USB power supply line “a2”, by establishing a part enclosed by a broken line “b1” in
The following is an explanation of an operation principle of the computer 1 when the solar battery unit 2 is connected to the USB connector 15.
When the solar battery unit 2 is connected to the USB connector 15, the USB data line “a1” becomes conductive to the solar battery unit 2, and thus the chipset 13 senses that any external device 2 is connected to the USB connector 15. The chipset 13 which has sensed that any external device 2 is connected to the USB connector 15 generates an interruption signal, and transmits it to the CPU 11. Thereby, the OS 201 recognizes that any external device 2 is connected to the USB connector 15.
The OS 201, which has recognized that any external device 2 is connected to the USB connector 15, issues an instruction to the EC 14 first to drive and control the input/output control circuit 16 to turn on the bus switch 161 and turn off the bus switch 162, to start power supply to the external device 2 connected to the USB connector 15. The EC 14 which has received the instruction supplies an enable signal only to the bus switch 161 of the input/output control circuit 16, and thereby starts power supply to the external device 2 connected to the USB connector 15.
Next, the OS 201 communicates with the external device 2 through the USB data line “a1”, recognizes the connected external device 2, and starts the application program 202 which is correlated with the external device 2 in advance. In this case, by communicating with the USB control circuit 23 of the solar battery unit 2, the OS 201 recognizes that the external device 2 connected to the USB connector 15 is the solar battery unit 2, and starts the power management utility program.
Specifically, also in the computer 1 of the present embodiment, the solar battery unit 2 connected to the USB connector 15 is once recognized as a usual USB device (which is operated by power supplied from the computer 1).
The power management utility program started by the OS 201 (as the solar battery unit 2 is connected to the USB connector 15) issues an instruction to the EC 14 first, through the OS 201, to drive and control the input/output control circuit 16 to turn off the bus switch 161 and turn on the bus switch 162, to prepare the computer 1 to receive power supply from the solar battery unit 2. The EC 14 which has received the instruction stops supplying the enable signal to the bus switch 161 of the input/output control circuit 16, and starts supplying an enable signal to the bus switch 162 of the input/output control circuit 16. Thereby, the path indicated by the arrow “b2” in
Next, through the driver for the solar battery unit 2, the power management utility program issues an instruction to the USB control circuit 23 of the solar battery unit 2 to output power to the USB power supply line “a2”. Thereby, power from the solar battery unit 2 is led to the charge circuit 19 through the USB connector 15 and the input/output control circuit 16, and the battery 18 is charged, or the computer 1 is operated by using the power.
Although this embodiment shows an example in which the solar battery unit 2 starts output of power to the USB power supply line “a2” in response to an instruction from the computer 1, the solar battery unit 2 may automatically start output of power to the USB power supply line “a2” instead, when input of power from the USB power supply line “a2” is stopped. In this case, the power management utility program may only issue an instruction to the EC 14 to drive and control the input/output control circuit 16 to turn off the bus switch 161 and turn on the bus switch 162.
When external device 2 is connected to the USB connector 15, the computer 1 recognizes the external device 2 as a usual USB device first, and establishes the power supply lines in the input/output control circuit 16, to start power supply by the USB power supply circuit 17 (Block A1).
Thereafter, when the external device 2 connected to the USB connector 15 is solar battery unit 2 (YES in Block A2), the computer 1 switches the power supply lines in the input/output control circuit 16, and starts charging of the battery 18 by the charge circuit 19, using power input from the solar battery unit 2 (Block A3).
On the other hand, when the external device 2 connected to the USB connector 15 is not solar battery unit 2 (NO in Block A2), the computer 1 maintains power supply by the USB power supply circuit 17, and executes usual processing performed when a USB device is connected (Block A4).
As described above, the computer 1 includes an original mechanism of temporarily dealing with the solar battery unit 2 connected to the USB connector 15 equally with usual USB devices, and thereby enables receiving power supply from the external device (solar battery unit) 2 connected to the USB connector 15 even when the computer 1 is operated, by using the USB power supply line “a2” to supply power to the external device 2 connected to the USB connector 15.
The various modules of the systems described herein can be implemented as software applications, hardware and/or software modules, or components on one or more computers, such as servers. While the various modules are illustrated separately, they may share some or all of the same underlying logic or code.
While certain embodiments have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the inventions. Indeed, the novel embodiments described herein may be embodied in a variety of other forms; furthermore, various omissions, substitutions and changes in the form of the embodiments described herein may be made without departing from the spirit of the inventions. The accompanying claims and their equivalents are intended to cover such forms or modifications as would fall within the scope and spirit of the inventions.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2009-272632 | Nov 2009 | JP | national |
