BATTERY DRIVING DEVICE, LOAD CONTROL METHOD, INTEGRATED CIRCUIT AND LOAD CONTROL PROGRAM

• US 20090237033A1
• Filed: 05/29/2007
• Published: 09/24/2009
• Est. Priority Date: 05/30/2006
• Status: Active Grant

• Current Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Original Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Inventors: Kanzaki, Hideyuki, Tojima, Masayoshi
• Granted Patent: US 8,502,505 B2
• Time in Patent Office: Days
• US Class Current: 320/134
• CPC Class Codes: H02J 7/007182 in response to battery voltage

Abstract

The present invention aims to provide a battery-driven device that is capable of extending an operating time of a battery (a secondary battery). A battery control unit 220 included in the battery-driven device of the present invention stores therein one or more voltage thresholds, and detects a sharp voltage drop that occurs immediately after the start of discharging of the battery fully charged, based on the current voltage of the battery and the stored voltage thresholds. On detecting the sharp voltage drop, the battery control unit controls power consumption of the battery to decrease.

Claims

1. A battery-driven device that is driven by a chargeable battery, comprising:

a storage unit operable to store therein one or more voltage thresholds in one-to-one association with one or more operations to be executed by the battery-driven device, each voltage threshold representing a voltage from which a voltage drop of the battery fully charged becomes moderate during execution of one of the operations associated therewith;

a voltage measuring unit operable to measure a voltage of the battery;

a specifying unit operable to specify one of the operations that is being executed by the battery-driven device;

an acquisition unit operable to acquire one of the voltage thresholds that corresponds to the specified operation from the storage unit;

a voltage comparison unit operable to compare the acquired voltage threshold with the measured voltage; and

a control unit operable to control power consumption of the battery to decrease if the measured voltage is equal to or more than the acquired voltage threshold.

2. The battery-driven device of claim 1, further comprising

a reception unit operable to receive the one or more voltage thresholds inputted by a user, wherein

the storage unit stores therein the one or more voltage thresholds received by the reception unit.

3. The battery-driven device of claim 1, further comprising:

a temperature threshold storage unit operable to store therein a prescribed temperature threshold;

a temperature measuring unit operable to measure a temperature of the battery; and

a temperature comparison unit operable to compare the temperature threshold with the measured temperature, wherein

the control unit further controls power consumption of the battery to decrease if a comparison result by the temperature comparison unit indicates the measured temperature is lower than the temperature threshold, regardless of a comparison result by the voltage comparison unit.

4. The battery-driven device of claim 1, wherein

the storage unit further stores therein a termination voltage threshold that represents a voltage from which a voltage drop of the battery becomes sharp when the battery has been continuously used,

the battery-driven device further comprises a termination judgment unit operable to compare the voltage measured by the voltage measuring unit with the termination voltage threshold, and

the control unit controls power consumption of the battery to decrease if the measured voltage is lower than the termination voltage threshold, regardless of a comparison result by the voltage comparison unit.

5. (canceled)

6. A load control method used in a battery-driven device that is driven by a chargeable battery,

the battery-driven device comprising

a storage unit operable to store therein one or more voltage thresholds in one-to-one association with one or more operations to be executed by the battery-driven device, each voltage threshold representing a voltage from which a voltage drop of the battery fully charged becomes moderate during execution of one of the operations associated therewith,

the load control method comprising:

a voltage measuring step of measuring a voltage of the battery;

a specifying step of specifying one of the operations that is being executed by the battery-driven device;

an acquisition step of acquiring one of the voltage thresholds that corresponds to the specified operation from the storage unit;

a voltage comparison step of comparing the acquired voltage threshold with the measured voltage; and

a control step of controlling power consumption of the battery to decrease if the measured voltage is equal to or more than the acquired voltage threshold.

7. A load control program used in a battery-driven device that is driven by a chargeable battery,

the battery-driven device comprising

a storage unit operable to store therein one or more voltage thresholds in one-to-one association with one or more operations to be executed by the battery-driven device, each voltage threshold representing a voltage from which a voltage drop of the battery fully charged becomes moderate during execution of one of the operations associated therewith,

the load control program comprising:

a voltage measuring step of measuring a voltage of the battery;

a specifying step of specifying one of the operations that is being executed by the battery-driven device;

an acquisition step of acquiring one of the voltage thresholds that corresponds to the specified operation from the storage unit;

a voltage comparison step of comparing the acquired voltage threshold with the measured voltage; and

a control step of controlling power consumption of the battery to decrease if the measured voltage is equal to or more than the acquired voltage threshold.

8. An integrated circuit used in a battery-driven device that is driven by a chargeable battery, the integrated circuit comprising:

a storage unit operable to store therein one or more voltage thresholds in one-to-one association with one or more operations to be executed by the battery-driven device, each voltage threshold representing a voltage from which a voltage drop of the battery fully charged becomes moderate during execution of one of the operations associated therewith;

a voltage measuring unit operable to measure a voltage of the battery;

a specifying unit operable to specify one of the operations that is being executed by the battery-driven device;

an acquisition unit operable to acquire one of the voltage thresholds that corresponds to the specified operation from the storage unit;

a voltage comparison unit operable to compare the acquired voltage threshold with the measured voltage; and

a control unit operable to control power consumption of the battery to decrease if the measured voltage is equal to or more than the acquired voltage threshold.