Power Transfer Between Devices

• US 20110016333A1
• Filed: 07/15/2009
• Published: 01/20/2011
• Est. Priority Date: 07/15/2009
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Hodges, Stephen E., Scott, James W.
• Granted Patent: US 8,898,485 B2
• Time in Patent Office: Days
• US Class Current: 713/300
• CPC Class Codes: G06F 1/266 Arrangements to supply power to external peripherals either directly from the computer or under computer control, e.g. supply of power through the communication port, computer controlled power-strips
• CPC Class Codes: H02J 7/342 The other DC source being a battery actively interacting with the first one, i.e. battery to battery charging with circuits for polarity protection H02J7/0034

Abstract

Power transfer between devices such as laptop computers, mobile phones, personal digital assistants, media players and other devices is described. In an embodiment power transfer is achieved either from a power source at a device or to a power source at that device using a bidirectional power transfer connector. In some embodiments a power management module at the device uses context, models or other information to control factors such as the power transfer direction, duration and amount. In examples, user preferences are taken into account. In an example, the bidirectional power transfer connector is provided as a USB connection or a wireless power transfer connection.

Claims

1. A device comprising:

a processor;

a memory coupled to the processor;

a power source;

at least one bidirectional power transfer connector arranged to enable the device to be connected to another device having a power source;

a power bus linking the power source and the power transfer connector and arranged to enable bidirectional power transfer relative to the power source; and

a power management module connected to the power bus and arranged to control the bi-directional power transfer.

2. A device as claimed in claim 1 wherein the power management module is arranged to control at least one of the:

amount, direction, duration, and type of the power transfer.

3. A device as claimed in claim 1 which further comprises a power transfer protocol engine arranged to enable communication with other devices enabled with the same protocol.

4. A device as claimed in claim 3 wherein the power transfer protocol engine is arranged to enable negotiation with other devices about any of:

amount, direction, duration, type of power transfer between those devices.

5. A device as claimed in claim 3 wherein the power transfer protocol engine is arranged to implement security measures.

6. A device as claimed in claim 1 wherein the power management module is arranged to use at least one of:

power transfer context information;

user preferences;

thresholds;

metrics;

rules;

type of connected device;

battery state.

7. A device as claimed in claim 1 wherein the power management module is arranged to form a model of the other device and to use that model to control the bidirectional power transfer.

8. A device as claimed in claim 1 wherein the power bus and at least one power transfer connector are arranged to be operable when the device is powered down.

9. A device as claimed in claim 1 wherein the power bus, power management module and at least one power transfer connector are arranged to be operable when the device is powered down.

10. A device as claimed in claim 3 wherein the processor is arranged to automatically detect the presence of at least one other device having a power source and wherein the power transfer protocol engine is arranged to negotiate potential power transfer with that detected device.

11. A device as claimed in claim 10 wherein the processor is arranged to provide a user interface and wherein the processor is arranged to generate a request at the user interface to request that a user establish a power transfer connection with the detected device on the basis of the negotiation.

12. A device as claimed in claim 1 wherein the power source is rechargeable and wherein the power management module is arranged to allow charging of the power source up to a target which is less than 100% and to allow transfer of power from the power source up to a maximum of all the power.

13. A device as claimed in claim 1 which further comprises at least one switch arranged to enable or disable the power transfer connector.

14. A portable device comprising:

a processor;

a memory coupled to the processor;

a power source;

at least one bidirectional power transfer connector arranged to enable the device to be connected to another device having a power source;

a power bus linking the power source and the power transfer connector and arranged to enable bidirectional power transfer relative to the power source both when the device is powered on and when the device is powered down; and

a power management module connected to the power bus and arranged to control the bidirectional power transfer

15. A portable device as claimed in claim 14 wherein the processor is arranged to provide a user interface arranged to enable a user to provide user power transfer preferences and wherein the power management module is arranged to take those preferences into account.

16. A portable device as claimed in claim 14 which further comprises at least one switch arranged to enable or disable the power transfer connector.

17. A method at a device having a power source comprising:

using a processor to detect the presence of at least one other device having a power source;

using the processor to assess whether power transfer negotiation with the detected device is possible;

using a power management module to make a decision about bidirectional power transfer between the devices;

establishing a connection between the detected device and a bidirectional power transfer connector at the device;

using a power transfer bus to carry out power transfer between the devices.

18. A method as claimed in claim 17 wherein the step of establishing a connection comprises using the processor to generate a request at a user interface of the device, the request being for the user to form a physical connection between the devices.

19. A method as claimed in claim 17 which further comprises using a power transfer protocol engine to carry out power transfer negotiation with the detected device.

20. A method as claimed in claim 17 which further comprises using the power management module to make the decision on the basis of user preferences.