System and method for powering an information handling system through a display cable
View Patent ↗A display provides power to an information handling system through a display cable. The display cable includes a power wire and an auxiliary channel. The display and information handling system communicate through the auxiliary channel to coordinate power transfer from the display to the information handling system, such as in the form of a trickle charge to a battery integrated in the information handling system.
1. An information handling system comprising:
a housing;
plural processing components disposed in the housing that cooperate to process visual information;
a battery disposed in the housing;
a display interface port operable to accept a display cable and to communicate visual information through the display cable to a display and having a bidirectional auxiliary channel to communicate management information, the display interface port further operable to provide power to the display and receive power from the display; and
a power manager running on a processing component, the power manager operable to request a battery charge from the display through the display cable auxiliary channel and to coordinate charging of the battery with power received at the display interface port through the display cable and from the display.
2. The information handling system of claim 1 wherein the power manager is further operable to receive power from the display cable at a selected of plural voltages.
3. The information handling system of claim 1 wherein the power manager is further operable to provide power to the display cable for use by the display at a selected of plural voltages.
4. The information handling system of claim 3 wherein the power manager receives power from the display cable at a first voltage and provides power to the display cable at a second voltage.
5. The information handling system of claim 4 wherein the first voltage comprises between nine and twenty Volts and the second voltage comprises approximately 3.3 Volts.
6. The information handling system of claim 1 wherein the power manager is further operable to coordinate charging of the battery with the processing components powered down.
7. The information handling system of claim 1 wherein the power manager further comprises a charge detector operable to detect a power source available at the display interface with the processing components powered down, the charge detector further operable to initiate coordinating of a battery charge with the power manager in response to detection of a power source.
8. The information handling system of claim 7 wherein the charge detector comprises a ground detector that detects a cable interface.
9. The information handling system of claim 1 further comprising:
a display cable having a power line; and
a display interfaced with the display interface port by the display cable, the display comprising a power source operable to receive a battery charge request from the power manager and to provide a charge to the display cable power line in response to the charge request.
10. A method for providing power to an information handling system from a display through a display cable, the method comprising:
providing power from the information handling system to the display through the display cable;
communicating a power request from the information handling system to the display through the display cable;
communicating a power request acknowledgment from the display to the information handling system through the display cable;
applying power at the display to a power wire of the display cable; and
receiving the power at the information handling system through the power wire.
11. The method of claim 10 wherein communicating a power request further comprises communicating the power request through a bidirectional auxiliary channel of the display cable.
12. The method of claim 10 wherein receiving the power at the information handling system further comprises applying the power to charge a battery.
13. The method of claim 10 wherein communicating a power request further comprises communicating power parameters of the information handling system to the display.
14. The method of claim 10 wherein communicating a power request acknowledgment further comprises communicating power parameters of the display to the information handling system.
15. The method of claim 14 wherein the power parameters comprise a voltage provided from the display.
16. The method of claim 10 further comprising:
powering down the information handling system;
detecting at the information handling system a power source available through the display cable; and
powering up at the information handling system components sufficient to coordinate a charge of a battery at the information handling system.
17. A system for providing power to an information handling system from a display, the system comprising:
a display cable having an integrated power line;
a graphics system integrated in the information handling system and operable to send graphics information through the display cable for presentation at the display;
a power manager running on a processor of the information handling system and operable to request power from the display with the information handling system powered down and having a battery with less than a full charge, receive confirmation of power available from the display, and in response to the confirmation to apply the power received from the display to the battery of the information handling system; and
a power source integrated in the display and operable to respond to the power manager request for power and to provide power from display to the information handling system through the display cable power line at predetermined power parameters.
18. The system of claim 17 wherein the power manager and power source communicate the power parameters through the display cable.
19. The system of claim 17 wherein the display cable comprises a bidirectional auxiliary channel, the power manager requesting power through the auxiliary channel.