Electrical computers and digital processing systems: support – Computer power control – Power conservation
Reexamination Certificate
1999-07-08
2002-08-27
Wong, Peter (Department: 2181)
Electrical computers and digital processing systems: support
Computer power control
Power conservation
Reexamination Certificate
active
06442699
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a method of controlling the power consumption in an information processor such as a personal computer depending on the change in the operating status of a running application program in the information processor, and more specifically, to a power control method which is used for a portable personal computer which can be driven by batteries and an apparatus therefor.
2. Description of the Related Art
Conventionally in a personal computer which can be driven by batteries, a method of controlling power depending on the operating status of an application program is roughly classified into four types described below.
The first method is “Power Saving Control System” described in Japanese Patent Laying-Open No. 4-125718. In this method, when a state where an application program waits for input and a state where there is no input from an input device are continued for a predetermined time period, the supply of a clock from a CPU and the supply of power is stopped. As a result, the power consumption is reduced, to extend the operating time of the batteries or reduce the battery capacity. That is, the method is a method of saving, when there is a little or no load inputted to the CPU, power by uniformly bringing the CPU into a dormant state.
The second method is “Electronic Equipment And Its Power Control Method” described in Japanese Patent Laying-Open No. 7-302138. In this method, a history of accesses to each device is first recorded for each application program. On the basis of the recording of the history of accesses, the time when the application program accesses the device is then predicted. The transition of the device to a power saving mode is then made on the basis of the predicted time. That is, the method is a method of comparing an amount of saved power which can be expected by making the transition of the device to the power saving mode from the current time to the predicted time with an amount of power required to return the device to a normal mode at the predicted time, to control the operation mode of the device such that the power consumption is made smaller.
The third method is “Method of Autonomously Reducing Power Consumption in a computer system by compiling a history of power consumption” described in Published Japanese Translation of PCT International Publication for Patent Application No. 8-503566 (Corresponding U.S. Pat. No. 5,339,445). In this method, the power consumption of a power consumption equipment in the computer system is monitored while an application program is being operated, and is recorded on a table of the computer system for holding the characteristics of resources of the system. The method is a method of calling the characteristics of the required resource when the application program is operated again, and automatically adjusting power supplied to the equipment in the computer system, to reduce the power consumption of the computer system.
The fourth method is a power control method generally used for an information processor which can be driven by both AC power and batteries which are supplied to homes and offices. In this method, it is judged whether the information processor is driven by the AC power or the batteries. When the information processor is driven by the batteries, it is operated using a power control method which has been previously set by a user. In this method, the operating speed of a CPU and the luminance of an LCD are reduced to fixed values designated by the user when the information processor is driven by the batteries to reduce the power consumption, thereby extending the driving time by the batteries.
The above-mentioned conventional power control method cannot cope with a rapid increase in the application program making maximum use of the performances of the CPU and peripherals obtained by recent rapid improvement of the processing speed of the CPU and the performance of the peripherals such as hard disk. Typical examples of such an application program are application software for reproducing a moving image or performing processing of the moving image such as recording of the moving image and application software for realizing a modem function.
Under such circumferences, when power is controlled by a method of uniformly reducing the operation speed of the CPU and the power consumption of the peripherals to fixed values, as in the above-mentioned first and fourth power control methods, a moving image processing application program or the like making maximum use of the performances of the CPU and the peripherals cannot be operated. Alternatively, the performances thereof cannot be sufficiently exhibited.
The above-mentioned second and third power control methods are superior in that power is controlled for each device used by the application program. When there is a request to particularly make maximum use of the performances of the CPU and the peripherals, as at the time of starting the application program and at the time of reproducing the moving image, in running the application program, the speed of the CPU and the amount of power are not changed depending on the request. When the load required of the resource greatly varies for each hardware depending on the contents of the operation of the application program, power control properly corresponding to the variation in the request is impossible. Accordingly, the application program cannot, in some cases, be operated, or the performances of the CPU and the peripherals cannot, in some cases, be sufficiently exhibited, as in the first and fourth power control methods.
In any of the conventional power control methods, in order to control power while properly running the application program, a user must previously set the power control method in detail or must always set the speed of the CPU to a sufficiently large value. It is very troublesome to sequentially and manually set the power control method in detail while the application program is running. Even if such troublesome detailed setting is performed, it is very difficult to perform the detailed setting at correct timing while the application program is running. If the speed of the CPU is fixedly set to a sufficiently large value, the power consumption is unnecessarily increased, and the driving time by the batteries is decreased. Therefore, the original object of the power control cannot be attained.
In the above-mentioned conventional power control method, an object is to extend the driving time of the information equipment driven by batteries, or reduce the size of the batteries in order to provide the same driving time. Therefore, the power control is considered only from the point of view of how power supplied to each of resources of the hardware is reduced at the time of running the application program. Therefore, the application program cannot be run normally, although the power consumption can be reduced, as described above.
Currently, global warming and exhaustion of energy resources are actually great problems. The reduction in the power consumption is not merely limited to the information equipment driven by batteries, but is a technique required of the overall electrical apparatus driven by AC power.
In running the application program, therefore, the minimum power required to properly drive each of the resources of the hardware must be supplied depending on the change in a state where the application program is running. In running the application program, therefore, power is prevented from being excessively supplied to the hardware any more than necessary to run the application program, to prevent the excessive power from being uselessly consumed. As a result, in running the application program, the power can be efficiently utilized without being uselessly utilized, and the power consumption can be reduced.
The present invention has been made in order to solve the above-mentioned problem and has for its object to provide a power control method, which is used in an electrical apparatus represented by an information ap
Chung-Trans X.
Matsushita Electric - Industrial Co., Ltd.
Wenderoth , Lind & Ponack, L.L.P.
Wong Peter
LandOfFree
Power control method and apparatus therefor does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Power control method and apparatus therefor, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Power control method and apparatus therefor will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2973334