System and method for portable information handling system integrated backlight control

1. An information handling system comprising:

a housing;

plural processing components disposed in the housing and operable to process information;

a display integrated in the housing, the display having a backlight and pixels, the backlight illuminating the pixels to present images formed with the information;

an inverter operable to power the backlight;

a controller interfaced with the inverter and operable to accept user brightness settings;

a graphics processor interfaced with the inverter and operable to generate automated brightness adjustments;

a light sensor interfaced with the inverter, the light sensor operable to detect ambient light to provide an ambient light brightness correction; and

a brightness module integrated in the inverter and interfaced with the controller, the graphics processor and the light sensor, the brightness module operable to sum the user brightness setting, the automated brightness adjustment and the ambient light brightness correction to determine a power output from the inverter to the backlight.

2. The information handling system of claim 1 further comprising brightness range settings stored at the brightness module, the brightness range settings defining maximum and minimum values for the power output from the inverter to the backlight.

3. The information handling system of claim 1 further comprising a calibration setting stored at the brightness module and operable to defined a predetermined power output from the inverter to the backlight.

4. The information handling system of claim 1 wherein the graphics processor communicates automated brightness adjustments to the inverter through a pulse width modulation bus.

5. The information handling system of claim 4 wherein the automated brightness adjustments comprise DPST adjustments.

6. The information handling system of claim 1 wherein the controller communicates user brightness settings to the inverter through a SMBus.

7. The information handling system of claim 1 wherein the controller communicates user brightness settings to the inverter through an I2C bus.

8. A method for setting inverter output to an information handling system display backlight, the method comprising:

receiving user brightness settings at the inverter;

receiving automated brightness adjustments at the inverter;

receiving ambient light measurements at the inverter; and

summing the user brightness settings, automated brightness adjustments and ambient light measurements at the inverter to determine a power output from the inverter to the backlight.

9. The method of claim 8 further comprising:

setting a brightness range for the power output from the inverter to the backlight; and

forcing the sum of the user brightness settings, automated brightness adjustments and ambient light measurements to remain within the brightness range.

10. The method of claim 8 further comprising:

setting a calibration adjustment at the inverter; and

including the calibration adjustment in the summing.

11. The method of claim 8 further comprising:

forcing user brightness settings, automated brightness adjustments and ambient light measurements to zero;

outputting power from the inverter to the backlight at a calibration adjustment;

comparing the backlight brightness with a predetermined brightness; and

setting the calibration adjustment to output the predetermined brightness.

12. The method of claim 8 wherein receiving user settings further comprises:

receiving user inputs at a controller to adjust the brightness of the backlight; and

sending the user inputs from the controller to the inverter through a SMBus.

13. The method of claim 8 wherein receiving user settings further comprises:

receiving user inputs at a controller to adjust the brightness of the backlight; and

sending the user inputs from the controller to the inverter through an I2C bus.

14. The method of claim 8 wherein receiving automated brightness adjustments further comprises:

generating the automated brightness adjustments with a graphics processor; and

sending the automated brightness adjustments from the graphics processor to the inverter through a pulse width modulation bus.

15. The method of claim 14 wherein the automated brightness adjustments comprise DPST adjustments.

16. An inverter for powering a backlight at variable brightness settings, the inverter comprising:

a user interface operable to accept user brightness settings;

a graphics processor interface operable to accept automated brightness adjustments of a graphics processor;

an ambient light sensor interface operable to accept ambient light measurements;

a brightness module operable to sum the user brightness setting, automated brightness adjustments and ambient light measurements to determine a brightness output setting; and

a power module operable to output variable power levels to a backlight to provide illumination from the backlight having the brightness output setting.

17. The inverter of claim 16 further comprising a brightness range register defining a maximum and minimum brightness output setting range, the brightness module further operable to force the brightness output setting to stay within the maximum and minimum brightness output setting range.

18. The inverter of claim 16 further comprising a calibration register defining a calibration brightness output setting, the brightness module further operable to force the brightness output setting to the calibration brightness output setting for calibration of a display.

19. The inverter of claim 16 wherein the user interface comprises a SMBus.

20. The inverter of claim 16 wherein the graphics processor interface comprises a pulse width modulation bus.