Method for automatic thermal calibration of a cooling system
This disclosure describes a method for operating a cooling device in a thermal system that is responsive to an operating parameter and dynamically changes the operating parameter to achieve a maximum operating temperature for any system regardless of the subsystem variation.
1. A method comprising:
operating a cooling device in a personal computer system responsive to a characteristic curve, the characteristic curve defining an operating parameter of the cooling device as a function of a temperature of the personal computer system; and
dynamically changing the characteristic curve in response to changes in the temperature of the personal computer system.
2. A method according to claim 1 wherein:
the characteristic curve comprises a minimum temperature and a slope;
operating the cooling device in a personal computer responsive to the characteristic curve comprises operating a fan responsive to the minimum temperature and the slope; and
dynamically changing the characteristic curve comprises shifting the characteristic curve responsive to the temperature of the personal computer system.
3. A method according to claim 2 wherein operating the fan responsive to the minimum temperature and slope comprises:
leaving the fan off when the temperature of the personal computer system is below the minimum temperature; and
turning the fan on when the temperature of the personal computer system reaches the minimum temperature.
4. A method according to claim 2 wherein shifting the characteristic curve responsive to the temperature of the personal computer system comprises:
setting the minimum temperature to a low value; and
gradually increasing the minimum temperature.
5. A method according to claim 4 wherein gradually increasing the minimum temperature comprises increasing the minimum temperature until the temperature of the personal computer system reaches a limit.
6. A method according to claim 4 wherein gradually increasing the minimum temperature comprises increasing the minimum temperature until an external event occurs.
7. A method according to claim 4 further comprising decreasing the minimum temperature if the minimum temperature becomes too high.
8. A method according to claim 1 wherein:
the characteristic curve comprises a minimum temperature and a slope;
operating the cooling device in a personal computer responsive to the characteristic curve comprises operating a fan responsive to the minimum temperature and the slope; and
dynamically changing the characteristic curve comprises changing the slope responsive to the temperature of the personal computer system.
9. A thermal management system for a personal computer system comprising:
a cooling device; and
a controller coupled to the cooling device, the controller configured to operate the cooling device responsive to a characteristic curve, the characteristic curve defining an operating parameter of the cooling device as a function of a temperature of the personal computer system, the controller further configured to dynamically change the characteristic curve in response to changes in the temperature of the personal computer system.
10. The thermal management system of claim 9 , wherein the operating parameter comprises a duty cycle of the cooling device.
11. The thermal management system of claim 9 , wherein the cooling device comprises a fan and the operating parameter comprises a speed of the fan.
12. A method comprising:
operating a cooling device in a personal computer in accordance with a control loop having a characteristic curve, the characteristic curve defining an operating parameter of the cooling device as a function of a temperature of the personal computer; and
dynamically changing the characteristic curve in response to changes in the temperature of the personal computer.
13. A method according to claim 12 wherein the characteristic curve comprises a minimum temperature and a slope.
14. A method according to claim 13 wherein the slope is the slope of a curve for the control loop.
15. An integrated circuit comprising circuitry configured to:
operate a cooling device in a personal computer responsive to a characteristic curve, the characteristic curve defining an operating parameter of the cooling device as a function of a temperature of the personal computer; and
dynamically changing the characteristic curve in response to changes in the temperature of the personal computer.