FAN CONTROL SYSTEM AND METHOD FOR CONTROLLING FAN SPEED

Abstract

A fan control system for processor is provided. The system has: a fan, configured to cool the processor; a power measurement module, coupled between the processor and a power supply of the processor, configured to measure the power of the processor; and a control module, coupled between the fan and the power measurement module, configured to control a speed of the fan according to the power of the processor, wherein when the power is higher than a predetermined power upper limit, the control module control the fan to increase the rotation speed.

Description

CROSS REFERENCE TO RELATED APPLICATIONS

This Non-provisional application claims priority under 35 U.S.C. §119(a) on Patent Application No(s).102,129,097, filed in Taiwan, Republic of China on Aug. 14, 2013, the entire contents of which are hereby incorporated by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a fan control system for processor and a method for controlling the fan rotation speed.

2. Description of the Related Art

Nowadays, computer system is usually configured with a central processing unit which provides higher performance, but consumes more energy and produces more heat. In the prior art, fans are often disposed with the processors to dissipate the heat for preventing the processors from being damaged by the heat.

A typical fan control system is shown in the patent document U.S. Ser. No. 13/302253. FIG. 1 is a schematic diagram of the fan control system in the patent document U.S. Ser. No. 13/302253. In this Fig., the fan control system 100 comprises a temperature sensing module 120, an embedded controller 130, and a fan 140, where the fan 140 is used to dissipate the heat from the central processing unit (CPU). The temperature sensing module 120 measures the temperature of the CPU 110 and provides the temperature data to the embedded controller 130, and then the embedded controller 130 controls the rotation speed of the fan 140 according to the temperature data, thus preventing the CPU 110 from being damaged by the heat.

Generally, the CPU improves its performance by increasing operating frequency. However, when the temperature rise of the CPU is detected, the operating frequency of the CPU may have been already increased for a while. In other words, the temperature-based method cannot control the rotation speed of the fan immediately, thus leading to the extension of the cooling time and a poor efficiency. Therefore, the present invention provides a new fan control technique for improving temperature control efficiency.

BRIEF SUMMARY OF THE INVENTION

The present invention provides a fan control system for processor. The system comprises: a fan, configured to cool the processor; a power measurement module, coupled between the processor and a power supply of the processor, configured to measure the power of the processor; and a control module, coupled between the fan and the power measurement module, configured to control a speed of the fan according to the power of the processor, wherein when the power is higher than a predetermined power upper limit, the control module control the fan to increase the rotation speed.

The present invention further provides a fan rotation speed controlling method. The method comprises: measuring the power of the processor; controlling a rotation speed of a fan according to the power of the processor. The controlling step further comprises: controlling the fan to increase the rotation speed when the power is higher than a predetermined power upper limit; and controlling the fan to decrease the rotation speed when the power is lower than a predetermined power lower limit.

A detailed description is given in the following embodiments with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention can be more fully understood by reading the subsequent detailed description and examples with references made to the accompanying drawings, wherein:

FIG. 1 is a schematic diagram of the fan control system in the prior art.

FIG. 2 is a schematic diagram of the fan control system according to an embodiment of the present invention.

FIG. 3 is a schematic diagram of the fan control system according to a preferred embodiment of the present invention.

FIG. 4 is a schematic diagram of the fan control system according to an embodiment of the present invention.

FIG. 5 is a flow chart of the method for controlling the fan control system according to an embodiment of the present invention.

FIG. 6 is a flow chart of the method for controlling the fan control system according to another embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

The following description is of the best-contemplated mode of carrying out the invention. This description is made for the purpose of illustrating the general principles of the invention and should not be taken in a limiting sense. The scope of the invention is best determined by reference to the appended claims.

Fan Control System

To improve the disadvantages of the prior art, the present invention provides a new fan control system. With the fan control system of the present invention, the temperature control efficiency can be significantly improved.

FIG. 2 is a schematic diagram of the fan control system according to an embodiment of the present invention. The fan control system 200 at least comprises a control module 232, a fan 240 and a power measurement module 260. The fan 240 of the present invention can be used to cool down a processor 210 of a computer system, and the rotation speed of the fan 240 can be controlled by the control module 232. In this embodiment, the processor 210 obtains the power from the power supply 250. The power measurement module 260 of the present invention is coupled between the processor 210 and the power supply 250 for measuring the power that the processor 210 consumes.

The control module 232 is coupled between the fan 240 and the power measurement module 260, and can control the rotation speed of the fan 240 according to the power of the processor 210 which is measured by the power measurement module 260. For example, in an embodiment, the control module 232 can set a predetermined power range, which has a power upper limit and a power lower limit. When the power measured by the power measurement module 260 is higher than the predetermined power upper limit, it means that the temperature of the processor 210 is going to rise, and the control module 232 has to control the fan 240 to increase its rotation speed. Oppositely, when the power measured by the power measurement module 260 is lower than the predetermined power lower limit, it means that there is no danger of overheating in the processor 210, and the control module 232 can control the fan 240 to decrease its rotation speed in order to save the power. Note that the processor 210 always varies its power earlier than its temperature. Therefore, by controlling the rotation speed of the fan according to the power, the temperature of the processor 210 can be adjusted faster and earlier, thus shortening the control time and improving the control efficiency.

In some other embodiments, the predetermined power range set by the control module 232 can be zero, and the predetermined power upper and the lower limits are with the same value. In some embodiments, the control module 232 can obtain the rotation speed from a lookup table (a correspondence table between rotation speed and power), through functions, and/or the combination thereof. The lookup table can be stored in various memories that can be either integrated into or separated from the control module 232. Various techniques such as linear or non-linear interpolations can be used to compute the values of the rotation speed. The present invention should not be limited to the previous embodiments, and those skilled in the art can determine the relationship between the rotation speed of the fan and the power of the processor according to the spirit of the present invention.

In an embodiment, the control module 232 of the present invention can be integrated into the embedded controller 230 of the computer system, and the embedded controller 230 may have a variety of other functions.

FIG. 3 is a schematic diagram of the fan control system according to a preferred embodiment of the present invention. Similarly to the embodiment in FIG. 2, the fan control system 300 in this embodiment at least has a control module 332, a fan 340 and a power measurement module 360. The fan 340 can be used to cool down a processor 310 of a computer system, and the rotation speed of the fan 340 can be controlled by the control module 332. In this embodiment, the processor 310 obtains the power from the power supply 350. The power measurement module 360 of the present invention is coupled between the processor 310 and the power supply 350 for measuring the power that the processor 310 consumes. The control module 332 can be disposed in an embedded controller 330. In this preferred embodiment, the power measurement module 360 comprises a current sensing unit 362. The current sensing unit 362 is used to measure the current that the power supply 350 provides to the processor 310. Therefore, in this embodiment, the control module 332 can calculate the power of the processor 310 according to the current measured by the current sensing unit 362. Those skilled in the art can understand that the power of an electronic component is the function of its current and voltage. In an embodiment, the voltage of the processor 310 can be obtained through estimation. Specifically, the voltage of the processor 310 can be read from a lookup table (a correspondence table between the voltage and current) stored in the control module 332. Note that the voltage usually has much smaller variation than the current on the processor, and in some embodiments, the voltage can be regarded as a fixed value. Therefore, with this manner, the control module 332 can efficiently calculate the power that the processor 310 consumes.

FIG. 4 is a schematic diagram of the fan control system according to an embodiment of the present invention. Similarly to the embodiment in FIG. 3, the fan control system 400 in this embodiment at least comprises a control module 432, a fan 440 and a power measurement module 460. The fan 440 can be used to cool down a processor 410 of a computer system, and the rotation speed of the fan 440 is controlled by the control module 432. In this embodiment, the processor 410 obtains power from a power supply 450. The power measurement module 460 of the present invention is coupled between the processor 410 and the power supply 450, and can measure the power that the processor 410 consumes. The control module 432 can be disposed in an embedded controller 430. In this embodiment, the power measurement module 460 comprises a current sensing unit 462 and a voltage sensing unit 464. The current sensing unit 462 is used to measure the current that the power supply 450 provides to the processor 410, and the voltage sensing unit 464 is used to measure the voltage that the power supply 450 provides to the processor 410. Therefore, in this embodiment, the control module 462 can easily calculate the power of the processor 410 according to the current sensed by the current sensing unit 462 and the voltage sensed by the current sensing unit 464. With respect to the embodiments in FIG. 3 which obtains the voltage from estimation, the method in this embodiment can obtain a more accurate voltage value and a more accurate power value. However, the circuitry in this embodiment is more complicated and expensive.

In some embodiment, the fan control system of the present invention further comprises a temperature sensing module (e.g., the temperature sensing modules 220, 320 and 420 in FIGS. 2, 3 and 4), and the control module (e.g. the control module 232, 332 and 432 in FIGS. 2, 3 and 4) can control the rotation speed of the fan according to both the temperature and the power of the processor. For example, in an embodiment, when the temperature measured by the temperature sensing module (220, 320 and 420) is higher than a predetermined temperature upper limit, the control module (e.g., 232, 332 or 432) controls the fan (e.g., 240, 340 or 440) to increase its rotation speed; and, when the temperature of the temperature sensing module (e.g., 220, 320 or 420) is lower than a predetermined temperature lower limit, the control module (e.g., 232, 332 or 432) controls the fan (e.g., 240, 340 or 440) to decrease its rotation speed. Oppositely, in another embodiment, when the temperature is higher than the predetermined temperature upper limit, the control module (e.g., 232, 332 or 432) controls the fan (e.g., 240, 340 or 440) to increase the rotation speed; and when the temperature is not higher than the predetermined temperature upper limit, the control module (e.g., 232, 332 or 432) controls the rotation speed of the fan according to the power.

Method For Controlling Rotation Speed of the Fan

The fan control system of the present invention has been fully described above. In addition to the fan control system, the present invention further provides a method for controlling the rotation speed of the fan.

FIG. 5 is a flow chart of the method for controlling the fan control system according to an embodiment of the present invention. The method 500 comprises: in step S502, measuring the power of the processor; and in step S504, controlling a rotation speed of a fan according to the power of the processor. In this embodiment, the step S504 further comprises: controlling the fan to increase the rotation speed when the power is higher than a predetermined power upper limit (sub-step S504A); and controlling the fan to decrease the rotation speed when the power is lower than a predetermined power lower limit (sub-step S504B). For example, steps S502 and S504 can be respectively performed by the power measurement module 260 and the control module 232 in FIG. 2. After step S504, the process returns to step S502.

FIG. 6 is a flow chart of the method for controlling the fan control system according to another embodiment of the present invention. The method 600 comprises: in step S602, measuring the power and the temperature of the processor and temperature (at the same or different time); in step S603, controlling the rotation speed of the fan according to the temperature of the processor; and in step S604, controlling the rotation speed of the fan according to the power of the processor. In this embodiment, the step S603 further comprises: controlling the fan to increase rotation speed when the temperature is higher than a predetermined temperature upper limit (sub-step S603A). However, if the measured temperature is not higher than the predetermined temperature upper limit, the process goes to step S604. In this embodiment, the step S604 further comprises: controlling the fan to increase the rotation speed when the power is higher than a predetermined power upper limit (sub-step S604A); and controlling the fan to decrease the rotation speed when the power is lower than a predetermined power lower limit (sub-step S604B). After step S604, the process returns to step S602. For example, the step S602 can be performed by the power measurement module 260 and temperature sensing module 220 in FIG. 2, and the step S603 and S604 can be performed by the control module 232 in FIG. 2. Those skilled in the art can understand the method of the present invention by referring to the embodiments of the fan control system of the present invention described above, and therefore the method will not be further discussed.

While the invention has been described by way of example and in terms of the preferred embodiments, it is to be understood that the invention is not limited to the disclosed embodiments. To the contrary, it is intended to cover various modifications and similar arrangements (as would be apparent to those skilled in the art). Therefore, the scope of the appended claims should be accorded the broadest interpretation so as to encompass all such modifications and similar arrangements.

Claims

1. A fan control system for processor, comprising:

a fan, configured to cool the processor;

a power measurement module, coupled between the processor and a power supply of the processor, configured to measure the power of the processor; and

a control module, coupled between the fan and the power measurement module, configured to control a speed of the fan according to the power of the processor, wherein when the power is higher than a predetermined power upper limit, the control module control the fan to increase the rotation speed.

2. The fan control system as claimed in claim 1, wherein when the power is lower than a predetermined power lower limit, the control module controls the fan to decrease the rotation speed.

3. The fan control system as claimed in claim 1, wherein the control module further comprises a current sensing unit, configured to measure a current that the power supply provides to the processor.

4. The fan control system as claimed in claim 3, wherein the control module calculates the power of the processor according to the current that sensed by the current sensing unit, and a voltage that corresponds to the current and is read from a correspondence table.

5. The fan control system as claimed in claim 3, wherein the control module further comprises a voltage sensing unit configured to measure a voltage that the power supply provides to the processor.

6. The fan control system as claimed in claim 5, wherein the control module calculates the power of the processor according to the current that sensed by the current sensing unit, and the voltage that sensed by the voltage sensing unit.

7. The fan control system as claimed in claim 1, further comprising:

a temperature sensing unit, for sensing temperature of the processor.

8. The fan control system as claimed in claim 7, wherein the control module controls the rotation speed of the fan according to the temperature of the processor, wherein the control module controls the fan to increase the rotation speed when the temperature is higher than a predetermined temperature upper limit.

9. The fan control system as claimed in claim 7, wherein the control module controls the fan to decrease the rotation speed when the temperature is lower than a predetermined temperature lower limit.

10. The fan control system as claimed in claim 7, wherein when the temperature is not higher than the predetermined temperature upper limit, the control module controls the rotation speed of the fan according to the power of the processor.

11. The fan control system as claimed in claim 1, wherein the control module is disposed in an embedded controller.

12. A fan rotation speed controlling method, comprising:

measuring the power of the processor;

controlling a rotation speed of a fan according to the power of the processor, further comprising:

controlling the fan to increase the rotation speed when the power is higher than a predetermined power upper limit; and

controlling the fan to decrease the rotation speed when the power is lower than a predetermined power lower limit.

13. The fan rotation speed controlling method as claimed in claim 12, further comprising:

measuring a current that is provided from the power supply to the processor.

14. The fan rotation speed controlling method as claimed in claim 13, further comprising:

calculating the power of the processor according to the measured current, and a voltage that corresponds to the measured current and is read from a correspondence table between the voltage and the current.

15. The fan rotation speed controlling method as claimed in claim 13, further comprising:

measuring a voltage that the power supply provides to the processor.

16. The fan rotation speed controlling method as claimed in claim 15, further comprising:

calculating the power of the processor according to the measured current and the voltage.

17. The fan rotation speed controlling method as claimed in claim 12, further comprising:

measuring the temperature of the processor.

18. The fan rotation speed controlling method as claimed in claim 17, further comprising:

controlling the rotation speed of the fan according to the temperature of the processor, further comprising:

controlling the fan to increase the rotation speed when the temperature is higher than a predetermined temperature upper limit; and

controlling the fan to decrease the rotation speed when the temperature is lower than a predetermined temperature lower limit.

19. The fan rotation speed controlling method as claimed in claim 17, further comprising:

controlling the rotation speed of the fan according to the temperature of the processor, further comprising:

controlling the fan to increase the rotation speed when the temperature is higher than a predetermined temperature upper limit; and

controlling the rotation speed of the fan according to the power of the processor when the temperature is not higher than the predetermined temperature upper limit.