Power consumption control method and information processing device

• US 20030188210A1
• Filed: 04/02/2003
• Published: 10/02/2003
• Est. Priority Date: 04/02/2002
• Status: Active Grant

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Nakazato, Takahiro
• Granted Patent: US 7,178,043 B2
• Time in Patent Office: Days
• US Class Current: 713/320
• CPC Class Codes: G06F 1/3203 Power management, i.e. event-based initiation of a power-saving mode
• CPC Class Codes: G06F 1/324 by lowering clock frequency
• CPC Class Codes: Y02D 10/00 Energy efficient computing, e.g. low power processors, power management or thermal management

Abstract

A controller reads a current value from a current sensor at regular intervals and calculates the average power consumption (Pavg) for a specified length of time (T). When the average power consumption (Pavg) exceeds an upper value (Pu) of power consumption, the controller performs throttling control of a CPU at a throttling rate of r %. If, nevertheless, the average power consumption (Pavg) is above the upper value (Pu), the controller sequentially increases the throttling rate in steps of r %. When the average power consumption (Pavg) is reduced below a lower value (Pl) as a result of the throttling control, the controller sequentially decreases the throttling rate in steps of r % until the upper value (Pu) is reached.

Claims

1. A power consumption control method comprising:

calculating an average power consumption based on power consumption of a system including a CPU; and

reducing the power consumption of the CPU when the average power consumption exceeds a specified value.

2. The power consumption control method according to claim 1, wherein reducing the power consumption of the CPU includes increasing a throttling rate of the CPU in steps to reduce the power consumption of the CPU in steps.

3. The power consumption control method according to claim 1, wherein reducing the power consumption of the CPU includes increasing a throttling rate of the CPU in steps when the average power consumption of the system exceeds an upper value of a predetermined range, and

decreasing the throttling rate of the CPU in steps when the average power consumption of the system is reduced below a lower value of the predetermined range.

4. The power consumption control method according to claim 1, wherein reducing the power consumption of the CPU includes increasing a throttling rate of the CPU in steps until the average power consumption of the system reaches a lower value of a predetermined range when the average power consumption of the system exceeds an upper value of the predetermined range, and

decreasing the throttling rate of the CPU in steps until the average power consumption of the system reaches the upper value when the average power consumption of the system is reduced below the lower value of the predetermined range.

5. The power consumption control method according to claim 1, wherein calculating the average power consumption of the system includes supplying operating power to the system from a battery pack including a microcomputer, receiving a voltage value or a current value that is applied to the system which is read by the microcomputer in the battery pack via a data bus, and calculating the average power consumption based on the voltage value or the current value, and reducing the power consumption includes performing throttling control on the CPU.

6. The power consumption control method according to claim 1, wherein the system is operated by power from either of an AC adapter and a battery pack, and the specified value is set to a different value for each of the AC adapter and the battery pack.

7. A power consumption control method comprising:

reading a current value applied to a system including a CPU;

converting the current value into a corresponding voltage value;

comparing the voltage value with a reference voltage value in a comparator; and

switching ON and OFF throttling control of the CPU according to a result of a comparison by the comparator to reduce power consumption of the system.

8. A power consumption control method comprising:

powering a system, including a CPU, from a battery pack;

calculating an upper value of power consumption of the system based on a preset battery operating time; and

performing throttling control on the CPU so as not to exceed the upper value to reduce the power consumption of the system.

9. The power consumption control method according to claim 8, wherein the preset battery operating time is selected by a user from a plurality of predetermined battery operating time choices.

10. The power consumption control method according to claim 8, wherein the preset battery operating time is set so as not to exceed a maximum operating time obtained by checking residual power of the battery pack.

11. An information processing device comprising:

a CPU; and

a controller that calculates an average power consumption of a system and controls to reduce power consumed by the CPU when the average power consumption exceeds a predetermined value.

12. The information processing device according to claim 11, wherein the controller is a controller that increases a throttling rate of the CPU in steps to reduce power consumption in steps when the average power consumption exceeds the predetermined value.

13. The information processing device according to claim 11, wherein the controller is a controller that increases a throttling rate of the CPU in steps when the average power consumption exceeds an upper value of a predetermined range and decreases the throttling rate of the CPU in steps to control power consumption in steps when the average power consumption is reduced below a lower value of the predetermined range.

14. The information processing device according to claim 11, further including:

a power supply circuit;

an AC adapter that produces DC power from AC power and provides the DC power to the power supply circuit;

a battery pack that is removably connected to the power supply circuit to provide power to the power supply circuit; and

a power switching device that provides power to the power supply circuit from the AC adapter when the AC adapter is connected to the power switching device and connects the battery pack to the power supply circuit when the AC adapter is not connected to the power switching device,

and wherein the controller detects system current applied to the power supply circuit from either the AC adapter or the battery pack to calculate the average power consumption based on the detected system current and controls the CPU at a predetermined throttling rate when the average power consumption exceeds the predetermined value,

and a throttling rate of the CPU is set to a first value for the AC adapter and a second value for the battery pack.

15. The information processing device according to claim 11, further includes:

a battery pack that has a microcomputer built in and provides power to the system, and wherein the controller is a controller that receives a voltage value or a current value from the system read by the microcomputer in the battery pack via a data bus to calculate the average power consumption of the system and performs throttling control on the CPU to reduce power consumption when the average power consumption exceeds a specified value.

16. The information processing device according to claim 11, further including:

a control unit that outputs a clock state control signal to switch the CPU between an operating state and a stopped state under control of the controller.

17. An information processing device comprising:

a current sensor that detects a current applied to a system including a CPU;

a current-to-voltage converter that converts a current value detected by the current sensor into a corresponding voltage value; and

a comparator that compares the voltage value obtained by the current-to-voltage converter with a reference voltage value to switch ON and OFF throttling control for the CPU.

18. An information processing device comprising:

a battery pack that provides power to a system including a CPU;

a battery operating time setting unit that sets an operating time of the battery pack based on an external input; and

a controller that calculates an upper value of power consumption of the system from the battery operating time and performs throttling control on the CPU so as not to exceed the upper value to reduce power consumption of the system.

19. The information processing device according to claim 18, wherein the battery operating time setting unit sets a plurality of battery operating time choices and causes a user to make a selection from the plurality of battery operating time choices.

20. The information processing device according to claim 19, wherein the battery operating time setting unit includes a display unit that displays the plurality of battery operating time choices and an input device through which the user makes a selection from the plurality of battery operating time choices.