Extended power management via frame modulation control

• US 20040021658A1
• Filed: 07/31/2002
• Published: 02/05/2004
• Est. Priority Date: 07/31/2002
• Status: Active Grant

• Current Assignee: ATI Technologies ULC (Advanced Micro Devices, Inc.)
• Original Assignee: ATI Technologies ULC (Advanced Micro Devices, Inc.)
• Inventors: Chen, I-Cheng
• Granted Patent: US 7,256,795 B2
• Time in Patent Office: Days
• US Class Current: 345/212
• CPC Class Codes: G06F 1/3228 Monitoring task completion, e.g. by use of idle timers, stop commands or wait commands
• CPC Class Codes: G06F 1/3265 Power saving in display device
• CPC Class Codes: G09G 2330/021 Power management, e.g. power saving
• CPC Class Codes: G09G 3/20 for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
• CPC Class Codes: G09G 3/2022 using sub-frames
• CPC Class Codes: G09G 3/3607 for displaying colours or for displaying grey scales with a specific pixel layout, e.g. using sub-pixels display of colours in flat matrix panels other than liquid crystal displays G09G3/2003; grey scales specific for television H04N3/127
• CPC Class Codes: Y02D 10/00 Energy efficient computing, e.g. low power processors, power management or thermal management

Abstract

Power consumption in a portable computer device that provides true-color simulation on a liquid crystal display can be realized by selectively operating a graphics controller that drives the LCD to selectively enable or disable true color simulation. Disabling dithering which provides true color simulation in an LCD, can significantly reduce power consumption by a portable computer device.

Claims

1. A method for providing user-specified power management in a portable computer device having a graphics controller and a liquid crystal display on which content is displayed comprised of:

enabling a user to select either a dithering mode of operation for said graphics controller or a non-dithering mode of operation for said graphics controller so as to reduce power consumption by said liquid crystal display.

2. The method of claim 1 wherein said graphics controller dithering mode is either a temporal dithering mode, a spatial dithering mode, or a combination of both temporal and spatial dithering modes.

3. The method of claim 2 wherein said graphics controller dithering modes display successive frames of differently-colored shades so as to provide a true-color simulation.

4. A method for providing user-specified power management in a portable computer device having a graphics controller and a liquid crystal display on which content is displayed comprised of:

providing a software-controlled user interface for said graphics controller;

enabling a user, via said user interface, to control said graphics controller to be operable in a graphics dithering mode providing at least a simulated true-color output on said liquid crystal device, or in a reduced-power-consumption, non-dithering mode of operation for said liquid crystal device.

5. The method of claim 4 wherein said graphics controller dithering mode is either a temporal dithering mode, a spatial dithering mode, or a combination of both temporal and spatial dithering modes.

6. The method of claim 5 wherein said graphics controller dithering modes display successive frames of differently-colored shades so as to provide a true-color simulation.

7. A method for providing user-specified power management in a portable computer device having a graphics controller and a liquid crystal display comprised of:

detecting when said portable computer device is operated from a battery;

selectively operating the graphics controller in either a true-color simulating graphics dithering mode or a non-dithering mode of operation so as to reduce power consumption by said liquid crystal display.

8. The method of claim 7 wherein said step of selectively enabling the graphics controller is further comprised of:

providing a user-interface to a user of said portable device to enable the portable device user to specify the graphics controller'"'"'s mode of operation as either a dithering mode or a non-dithering mode.

9. The method of claim 7 wherein said step of selectively enabling the graphics controller is further comprised of:

automatically operating said graphics controller in said non-dithering mode.

10. The method of claim 7 wherein said step of selectively enabling the graphics controller is further comprised of:

automatically operating said graphics controller in said non-dithering mode, if the content displayed on the liquid crystal display does not require true-color or a true-color simulation.

11. The method of claim 7 wherein said graphics controller dithering mode is either a temporal dithering mode, a spatial dithering mode, or a combination of both temporal and spatial dithering modes.

12. The method of claim 11 wherein said graphics controller dithering modes display successive frames of differently-colored shades so as to provide a true-color simulation.

13. A method for providing user-specified power management in a portable computer device having a graphics controller and a liquid crystal display comprised of:

detecting when said portable computer device is operated from a battery;

determining when said portable computer device is displaying on said liquid crystal display, content that contains color;

if said content contains color, selectively operating the graphics controller in either a graphics dithering mode to render true-color simulation, or a non-dithering mode of operation for so as to reduce power consumption by said liquid crystal display.

14. The method of claim 13 wherein said step of selectively operating the graphics controller is comprised of:

operating said graphics controller in a non-dithering mode under software control when said portable computer device operates from a battery.

15. The method of claim 13 wherein said step of selectively operating the graphics controller is comprised of:

operating said graphics controller in a non-dithering mode under software control when said portable computer device operates from a battery and when any content displayed on said liquid crystal display is not displaying true-color content.

16. A portable computer device having a liquid crystal display comprised of:

a central processor means, providing a software controlled power management user interface;

a graphics controller operably coupled to the central processor, said graphics controller being operable via said user interface in a graphics dithering mode to provide a true-color simulation by said liquid crystal display, or a non-dithering mode of operation to reduce power consumption by said liquid crystal display.

17. The portable computer device of claim 16 wherein said graphics controller dithering mode is either a temporal dithering mode, a spatial dithering mode, or a combination of both temporal and spatial dithering modes.

18. The portable computer device of claim 17 wherein said graphics controller dithering modes display successive frames of differently-colored shades so as to provide a true-color simulation.