Method and apparatus for determining residual battery voltage

• US 5,784,295 A
• Filed: 05/09/1995
• Issued: 07/21/1998
• Est. Priority Date: 06/12/1992
• Status: Expired due to Term

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Hinohara, Makoto
• Primary Examiner(s): Cosimano, Edward R.
• Application Number:
  US08/437,524
• Time in Patent Office: 1,169 Days
• Field of Search: 340/636, 364/480, 364/481, 364/483, 364/550, 364/551.01, 324/427
• US Class Current: 702/63
• CPC Class Codes: G01R 31/3648 comprising digital calculation means, e.g. for performing an algorithm
• CPC Class Codes: G01R 31/3835 involving only voltage measurements

Abstract

A portable electronic apparatus utilizes battery characteristics to detect the operating condition of the battery supplying power to the apparatus. Battery voltage is detected in different operating states of the apparatus and the residual battery voltage is determined on the basis of the detected different state battery voltage.

Claims

1. An electronic apparatus having a unit operated by a battery, said unit comprising an information processing portion and a display portion for displaying information processed by said information processing portion and said unit having at least first and second operating states, said first operating state being one in which said battery outputs a first amount of power to operate said information processing portion and said second operating state being one in which said battery outputs a second amount of power to operate both said information processing portion and said display portion, said first and second amounts of power each varying over time as said battery ages, said apparatus comprising:

voltage detection means for detecting a voltage of said battery with said unit in said first operating state and again with said unit in said second operating state;

means for determining a residual amount of the battery voltage on the basis of the battery voltage detected by said voltage detection means; and

a CPU arranged to control, at selected times, said voltage detection means to operate during each of said operating states.

2. The electronic apparatus according to claim 1, further comprising indicating means for indicating a result of determination by said determination means.

3. The electronic apparatus according to claim 1, further comprising A/D conversion means for converting a result of detection of said voltage detection means.

4. The electronic apparatus according to claim 3, further comprising table storage means for storing a table of data to which digital data obtained by said A/D conversion means is compared.

5. An electronic apparatus having a main unit operated by a battery, said main unit including a first unit for inputting data, a second unit for displaying the input data and a third unit for printing the displayed data, and said main unit having at least first and second operating states, said first operating state being one in which said battery outputs a first amount of power to operate said main unit without at least one of said first, second and third units and said second operating state being one in which said battery outputs a second amount of power to operate said main unit together with said at least one of said first, second and third units, said first and second amounts of power each varying over time as said battery ages, said apparatus comprising:

voltage detection means for detecting a voltage of said battery with said unit in said first operating state and again with said unit in said second operating state;

means for determining a battery voltage difference on the basis of the battery voltages detected by said voltage detection means;

means for calculating the residual amount of said battery voltage based upon a determination of said determining means;

informing means for informing a user of a residual amount of said battery voltage on the basis of determination of said calculating means; and

a CPU arranged to control, at selected times, said voltage detection means to operate during each of said operating states.

6. The electronic apparatus according to claim 5, further comprising A/D conversion means for converting a result of the detection of said voltage detection means.

7. The electronic apparatus according to claim 6, further comprising table storage means for storing a table of data to which digital data obtained by said A/D conversion means is compared.

8. A method of detecting a residual amount of battery voltage in an electronic apparatus having a unit operated by said battery, said unit comprising a unit for inputting data, a unit for displaying the input data and a unit for printing the displayed data, and the unit having at least first and second operating states, the first operating state being one in which the battery outputs a first amount of power to operate said unit for inputting data and the second operating state being one in which the battery outputs a second amount of power to operate said unit for inputting data and at least one of said unit for displaying the input data and said unit for printing the displayed data, the first and second amounts of power each varying over time as the battery ages, said method comprising the steps of:

operating a CPU to detect a battery voltage with the unit in the first operating state and again with the unit in the second operating state; and

determining the residual amount of the battery voltage on the basis of the detected battery voltages.

9. A method of detecting a residual amount of battery voltage in an electronic apparatus having a unit operated by said battery, said unit including a display means for displaying information processed by said electronic apparatus and a light source arranged facing said display means, and the unit having at least first and second operating states, the first operating state being one in which the battery outputs a first amount of power to operate said unit without at least one of said display means and said light source and the second operating state being one in which the battery outputs a second amount of power to operate said unit together with at least one of said display means and said light source, the first and second amounts of power each varying over time as the battery ages, said method comprising the steps of:

operating a CPU to detect a battery voltage with the unit in the first operating state;

storing the detected first state battery voltage;

detecting the battery voltage with the unit in the second operating state;

storing the detected second battery voltage; and

determining the residual amount of the battery voltage on the basis of the stored first and second state battery voltages.

10. The method of detecting a residual amount of a battery voltage according to claim 9, further comprising the step of indicating the residual amount of the battery voltage on the basis of a result of the determination.

11. A method of detecting a residual amount of a battery voltage in an electronic apparatus having a main unit operated by said battery, said main unit including a first unit for inputting data, a second unit for displaying the input data and a third unit for printing the displayed data, said method comprising the steps of:

putting said main unit in a first state in which said battery supplies power to operate said main unit without supplying power to at least one of said first, second and third units;

detecting a battery voltage in said first state of said unit;

operating a CPU to put said main unit in a second state in which said battery supplies power to operate said main unit together with said at least one of said first, second and third units;

detecting the battery voltage in said second state of said unit; and

determining the residual amount of the battery voltages detected in said first and second states.

12. The method of detecting a residual amount of a battery voltage according to claim 11, further comprising the step of indicating the residual amount of battery voltage on the basis of the result of the determination.

13. An electronic apparatus having a unit operated by a battery, said unit including a display means for displaying information processed by said electronic apparatus and a light source arranged facing said display means, and said unit having at least first and second operating states, said first operating state being one in which said battery outputs a first amount of power to operate said unit without at least one of said means for displaying information and said light source and said second operating state being one in which said battery outputs a second amount of power to operate said unit together with said at least one of said means for displaying information and said light source, said first and second amounts of power each varying over time as said battery ages, said apparatus comprising:

manual operation means;

voltage detecting means, including a CPU, for detecting a voltage of said battery in response to an operation of said manual operation means; and

means for determining a residual amount of said battery voltage on the basis of the battery voltages detected by said voltage detection means with said unit in said first operating state and again with said unit in said second operating state.

14. The electronic apparatus according to claim 13, further comprising A/D conversion means for converting a result of detection of said voltage detection means.

15. The electronic apparatus according to claim 13, further comprising table storage means for storing a table of data to which digital data obtained from said A/D conversion means is compared.

16. An electronic apparatus having a main unit operated by a battery, said main unit including a first unit for inputting data, a second unit for displaying the input data and a third unit for printing the displayed data, said main unit having at least first and second operating states, said first operating state being one in which said battery outputs a first amount of power to operate said main unit without at least one of said first, second and third units and said second operating state being one in which said battery outputs a second amount of power to operate said main unit together with said at least one of said first, second and third units, said first and second amounts of power each varying over time as said battery ages, said apparatus comprising:

a manually operated switch;

means, including a CPU, for operating said units responsive to operation of said manually operated switch;

voltage detecting means for detecting a voltage of said battery in response to an operation of said manually operated switch; and

a circuit for determining a residual amount of the battery voltage on the basis of the battery voltages detected by said voltage detection means with said unit in said first operating state and again with said unit in said second operating state.

17. The electronic apparatus according to claim 16, further comprising A/D conversion means for converting a result of the detection of said voltage detection means.

18. The electronic apparatus according to claim 16, further comprising table storage means for storing a table of data to which detected data obtained from said A/D conversion means is compared.

19. An electronic apparatus being operated by a power supply from a power source, comprising:

input means for inputting information;

storage means for storing the information;

display means for displaying the information stored by said storing means;

illumination means for illuminating said display means;

instruction output means, arranged in said input means, for inputting an instruction to measure a residual amount of the power source;

detection means for detecting a voltage of the power source;

illumination control means for controlling said illumination means to illuminate in response to the instruction input by said instruction input means;

first detection control means for detecting the voltage of the power source during operation of said electronic apparatus when said illumination means has been controlled to illuminate by said illumination control means;

first detected voltage storage means for storing the voltage detected by said first detection control means;

second detection control means for detecting for detecting the voltage of the power source during operation of said electronic apparatus when said illumination means has gone out after illuminating;

second detected voltage storage means for storing the voltage detected by said second detection control means; and

display control means for controlling so as to display the residual amount of the power source by calculating a difference between said first detected voltage storage means and said second detected voltage storage means,

said instruction output means and said first and second detection control means being arranged to be controlled by a CPU.

20. An electronic apparatus according to claim 19, wherein said illumination means is a backlight of said display means.

21. An electronic apparatus according to claim 19, wherein said display control means comprises a standard memory having a standard voltage and compares the detected voltage with the standard voltage.

22. An electronic apparatus being operated by a power supply from a power source, comprising:

input means for inputting information;

storage means for storing the information;

display means for displaying the information stored by said storage means;

illumination means for illuminating said display means;

an instruction input device, being arranged in said input means, for inputting an instruction to measure a residual amount of the power source;

a drive control device for controlling at least one of said means to operate in response to the instruction input by said instruction input device;

a first detection control device for detecting the voltage of the power source when operation of a plurality of said means has been controlled by said drive control device;

a first detected voltage storage device for storing the voltage detected by said first detection control device;

a second detection control device for detecting the voltage of the power source when driving some of said plurality of means has been stopped;

a second detected voltage storage device for storing the voltage detected by said second detection control device,

said first and second instruction control devices being arranged to be controlled by a CPU; and

a display control device for controlling said display device to display the residual amount of the power source by calculating a difference between said first detected voltage storage means and said second detected voltage storage means.

23. An electronic apparatus according to claim 22, wherein said illumination means is a backlight.

24. An electronic apparatus being operated by a power supply from a power source, comprising:

input means for inputting information;

storage means for storing the information;

display means for displaying the information stored by said storage means;

illumination means for illuminating said display means;

a characteristic memory for storing characteristics of the power source;

an instruction input device, being arranged in said input means, for inputting an instruction to measure a residual amount of the power source;

a detection device for detecting a voltage of the power source;

a drive control device for controlling some of said means to drive in response to the instruction input by said instruction input device;

a first detection control device for detecting the voltage of the power source when driving of some of said means has been controlled by said drive control device;

a first detected voltage storage device for storing the voltage detected by said first detection control device;

a second detection control device for detecting the voltage of the power source when driving of some of said means has been stopped;

said first and second detection devices being arranged to be controlled by a CPU;

a second detected voltage storage device for storing the voltage detected by said second detection control device; and

a display control device for referring to said characteristic memory and controlling said display means to display the residual amount of the power source in accordance with the detected voltage stored by said first and second detected voltage storage device.