Voltage detecting device, battery remaining voltage detecting device, voltage detecting method, battery remaining voltage detecting method, electronic timepiece and electronic device

• US 6,563,766 B1
• Filed: 11/22/2000
• Issued: 05/13/2003
• Est. Priority Date: 11/24/1999
• Status: Active Grant

• Current Assignee: Seiko Epson Corporation (Seiko Group)
• Original Assignee: Seiko Epson Corporation (Seiko Group)
• Inventors: Nakamiya, Shinji
• Primary Examiner(s): MISKA, VIT W
• Application Number:
  US09/718,750
• Time in Patent Office: 902 Days
• Field of Search: 368/64, 368/66, 368/204, 320/137, 320/161, 320/162
• US Class Current: 368/64
• CPC Class Codes: G04C 10/04 with means for indicating the condition of the power supply in general G01R31/36

Abstract

A voltage detection and a remaining battery voltage display for a secondary power source so as to notify the user of the remaining battery voltage of the secondary power source at the optimal timing and in an accurate manner. A voltage correlated to the power source capacity of the secondary power source is detected as a detection voltage. The detection voltage is directly output if a rapid charging is not being detected. If the rapid charging is being detected, the detection voltage is output after being corrected for an amount of the apparent voltage boost which occurs in the secondary power source due to the rapid charging. The detection voltage thus obtained is compared with a predetermined reference voltage so as to discriminate the remaining capacity of the secondary power source.

Claims

1. A voltage detecting device for detecting a voltage of a secondary power source including:

a rapid charging detecting unit for detecting whether rapid charging to said secondary power source is performed or not;

a voltage generating unit for outputting as a detection voltage, when said rapid charging is not detected, a detected voltage having a correlation to an amount of stored electricity of said secondary power source, and outputting as said detection voltage, when said rapid charging is detected, a corrected voltage in which a correction voltage corresponding to an apparent boosted voltage generated in said secondary power source due to said rapid charging is cancelled from said detected voltage; and

a voltage detection result output unit for outputting a voltage detection result signal, based on said detection voltage.

2. The voltage detecting device as claimed in claim 1, wherein said voltage detection result output unit compares said detection voltage with a predetermined reference voltage to obtain a comparative result and outputs said result as said voltage detection result signal.

3. The voltage detecting device as claimed in claim 1, wherein said rapid charging detecting unit includes:

a charging condition detecting unit for detecting charging to said secondary power source; and

a rapid charging condition discrimination unit for discriminating a transition to a rapid charging condition in which said rapid charging is performed, upon detecting that said charging to said secondary power source remains during a time longer than a predetermined charging reference time.

4. The voltage detecting device as claimed in claim 3, wherein said secondary power source is charged by a power generating device;

and said charging condition detecting unit includes a power generation current discriminating unit for discriminating whether a power generation current volume output from said power generating device exceeds a predetermined power generation current volume or not.

5. The voltage detecting device as claimed in claim 3, wherein said secondary power source is charged by a power generating device;

and said charging condition detecting unit includes a stored power voltage discriminating unit for calculating a stored power voltage of said secondary power source based on a power generation current output from said power generating device to discriminate whether said stored power voltage exceeds a predetermined reference stored power voltage or not.

6. The voltage detecting device as claimed in claim 3, wherein said secondary power source is charged by a power generating device;

and said charging condition detecting unit includes;

a comparing unit for comparing a voltage of an output terminal in said power generating device with a prescribed voltage corresponding to a terminal voltage in said secondary power source; and

a charging condition discriminating unit for discriminating as being in a charging condition a case in which said voltage of said output terminal exceeds said terminal voltage of said secondary power source, based on a comparative result of said comparing unit.

7. The voltage detecting device as claimed in claim 3, wherein said charging condition detecting unit discriminates whether or not charging to said secondary power source is performed by monitoring a route different from a charging route of said charging.

8. The voltage detecting device as claimed in claim 1, wherein said secondary power source is charged by a power generating device;

and said rapid charging detecting unit includes;

a power generating condition detecting unit for detecting a power generating condition in said power generating device; and

a rapid charging condition discriminating unit for discriminating as being in a rapid charging condition upon detecting that said power generating condition is remains during a time longer than a predetermined power generating reference time.

9. The voltage detecting device as claimed in claim 8, wherein said power generating condition detecting unit includes:

an output voltage comparing unit for comparing an output voltage of said power generating device with a predetermined reference power generating voltage; and

a power generating condition discriminating unit for discriminating, based on a comparative result of said output voltage comparing unit, whether a power generating condition is present or not.

10. The voltage detecting device as claimed in claim 1, wherein said secondary power source is charged by a power generating device;

said rapid charging detecting unit includes;

a charging condition detecting unit for detecting a condition of charging to said secondary power source;

a power generating condition detecting unit for detecting a power generating condition of said power generating device; and

a rapid charging condition discriminating unit for discriminating as being in a rapid charging condition a case in which detection of said charging is continuously repeated during a time longer than a predetermined charging reference time, or a case in which detection of said power generating condition is continuously repeated during a time longer than a predetermined power generating reference time; and

said power generating reference time is set longer than said charging reference time.

11. The voltage detecting device as claimed in claim 8, wherein said power generating condition detecting unit discriminates whether or not a power generation is implemented by monitoring a route different route from a charging route of said secondary power source.

12. The voltage detecting device as claimed in claim 1, wherein said voltage generating unit comprises:

a detectedd voltage output unit for outputting a detected voltage having a correlation to an amount of a stored electricity of said secondary power source; and

a voltage correction unit for canceling from said detected voltage, when said rapid charging is detected, a correction voltage corresponding to an apparent boosted voltage generated in said secondary power source due to said rapid charging.

13. The voltage detecting device as claimed in claim 12, wherein

said detected voltage output unit produces a plurality of different detected voltages;

and

said voltage correction unit produces said correction voltage in a manner to correspond to a respective one of said plurality different detected voltages.

14. The voltage detecting device as claimed in claim 1, wherein said correction voltage is a predetermined offset voltage.

15. The voltage detecting device as claimed in claim 1, further including:

a power source kind discriminating unit for discriminating a kind of said secondary power source; and

a discriminating result selecting unit for selecting any one of a plurality of voltage detecting result signal corresponding to said plurality of detected voltages, based on a discriminating result of said power source kind discriminating unit to output said selected voltage detecting result signal.

16. The voltage detected device as claimed in claim 1, wherein said voltage detection result output unit discriminates a voltage of said secondary power source into a plurality of stages having predetermined voltage ranges;

and any one of said correction voltage or said detected voltage is set in a respective one of said stages.

17. The voltage detected device as claimed in claim 15, wherein at least said correction voltage in a group of said correction voltage and said detected voltage output from said detected voltage output unit is set in a manner to correspond to a kind of said secondary power source;

and said voltage correction unit includes;

a correction voltage producing unit for producing a plurality of correction voltages corresponding to a kind of said secondary power source; and

a correction voltage selecting unit for selecting a correction voltage corresponding to a discriminating result in said power source kind discriminating unit to output said selected correction voltage.

18. The voltage detecting device as claimed in claim 15, wherein said correction voltage and said detection voltage output from said detection voltage output unit are respectively set in a manner to correspond to a kind of said secondary power source;

and said detection voltage output unit includes;

a detected voltage producing unit for producing a plurality of detected voltages corresponding to a kind of said secondary power source;

a detected voltage selecting unit for selecting a detected voltage corresponding to a discriminating result in said power source kind discriminating unit to output said selected detected voltage; and

said voltage correction unit includes;

a correction voltage producing unit for producing a plurality of correction voltages corresponding to a kind of said secondary power source; and

a correction voltage selecting unit for selecting a correction voltage corresponding to a discriminating result in said power source kind discriminating unit to output said selected correction voltage.

19. The voltage detecting device as claimed in claim 15, wherein said power source kind discriminating unit discriminates a kind of said secondary power source, based on a kind designating signal from outside.

20. The voltage detecting device as claimed in claim 19, wherein said kind designating signal is input through an external input terminal or input from a memory.

21. The voltage detecting device as claimed in claim 3, wherein said rapid charging condition discriminating unit discriminates a period of time when said rapid charging continues being detected by said rapid charging detecting unit and a period of time when a prescribed waiting time is passed after said rapid charging is not continuously detected as said rapid charging condition.

22. The voltage detecting device as claimed in claim 3, wherein said rapid charging condition discriminating unit discriminates a period of time when said rapid charging continues being detected by said rapid charging detecting unit and a period of time when a prescribed waiting time is passed after said rapid charging stops being detected, as said rapid charging condition.

23. The voltage detecting device as claimed in claim 21, wherein said waiting time is set as a period of time when an apparent voltage boost generated in a rapid charging in said secondary power source becomes almost zero and stable.

24. The voltage detecting device as claimed in claim 21, further including:

a power source kind discriminating unit for discriminating a kind of said secondary power source;

a waiting time storage unit for storing a plurality of waiting times; and

a waiting time selecting unit for selecting anyone of said waiting times stored in said waiting time storage unit, based on a discriminating result in said power source kind discriminating unit to output said selected waiting time.

25. The voltage detecting device as claimed in claim 21, wherein a measurement of said waiting time is initialized when said rapid charging is detected again before said waiting time is passed.

26. The voltage detecting device as claimed in claim 1, wherein said detected voltage is a voltage after a voltage boost and drop is implemented at a prescribed voltage boost and drop multiplying factor;

and further including;

a discriminating result selecting unit for selecting any one of a plurality of voltage detection results corresponding to a plurality of said detected voltages, based on said voltage boost and drop multiplying factor to output said selected voltage detection result.

27. The voltage detecting device as claimed in claim 16, further including:

a discriminating result selecting unit for selecting any one of a plurality of voltage detection results corresponding to a plurality of said detected voltages, based on said stage to output said selected voltage detection result.

28. A battery remaining capacity detecting device including:

a voltage detecting device as claimed in claim 1; and

a remaining capacity discriminating unit for discriminating a remaining capacity which is an amount of electricity which can be output from said secondary power source, based on a voltage detecting result output from said voltage detecting device.

29. A battery remaining capacity detecting device including:

a voltage detecting device as claimed in claim 21; and

a remaining capacity discriminating unit for discriminating a remaining capacity which is an amount of an electricity which can be output from said secondary power source, based on a voltage detecting result output from said voltage detecting device; and

said remaining capacity discriminating unit discriminates a remaining capacity of said secondary power source in such manner that when a predetermined condition is satisfied during a period of time when said waiting time is passed after said rapid charging is not continuously detected as said rapid charging condition, a transition to other conditions except said rapid charging condition is effected.

30. The battery remaining capacity detecting device as claimed in claim 29, wherein said predetermined condition is a case in which a voltage of said secondary power source is below a predetermined lower limit voltage.

31. The battery remaining capacity detecting device as claimed in claim 29, wherein said predetermined condition is a case in which a remaining capacity of said secondary power source discriminated by said remaining capacity discriminating unit becomes a predetermined remaining capacity.

32. The battery remaining capacity detecting device as claimed in claim 28, wherein said battery remaining capacity detecting device includes a remaining capacity comparing unit for comparing a remaining capacity of said secondary power source immediately before said rapid charging condition is over with a remaining capacity of said secondary power source immediately after transitioning to said non-rapid charging condition, when a transition from said rapid charging condition to said non-rapid charging condition is effected;

and

said voltage detection result output unit discriminates a voltage of said secondary power source into a plurality of stages having predetermined voltage ranges based on a comparative result in said remaining capacity comparing unit, and when a stage corresponding to a remaining capacity of said secondary power source immediately after transition to said non-rapid charging condition is lower than a stage corresponding to a remaining capacity of said secondary power source immediately before said rapid charging is over, said voltage detection result output unit discriminates said stage corresponding to said remaining capacity of said secondary power source immediately after transition to said non-rapid charging condition as a stage corresponding to a present remaining capacity.

33. The battery remaining capacity detecting device as claimed in claim 28, wherein said voltage detection result output unit discriminates a voltage of said secondary power source into a plurality of stages having predetermined voltage ranges and said battery remaining capacity detecting device further includes:

a remaining capacity comparing unit for comparing a stage of a remaining capacity of said secondary power source immediately before said rapid charging condition is over with a stage of a remaining capacity of said secondary power source immediately after transitioning to said non-rapid charging condition, when a transition from said rapid charging condition to said non-rapid charging condition is effected; and

a rank-up inhibiting control unit for inhibiting rank-up of said stage based on a comparative result in said remaining capacity comparing unit in a way that until a predetermined rank-up inhibiting cancellation condition is satisfied, a rank-up of stage is inhibited when a stage corresponding to a remaining capacity of said secondary power source immediately after transition to said non-rapid charging condition is higher than a stage corresponding to a remaining capacity of said secondary power source immediately before said rapid charging is over.

34. The battery remaining capacity detecting device as claimed in claim 33, wherein said rapid charging detecting unit includes a charging condition detecting unit for detecting a charging condition to said secondary power source;

and said rank-up inhibiting cancellation condition is a case in which a charging condition is detected by said charging detecting unit.

35. The battery remaining capacity detecting device as claimed in claim 28, wherein said battery remaining capacity detecting device includes a charging cut-off unit for forcefully cutting off a charging of said secondary power source, when detecting a voltage having a correlation to a remaining capacity of said secondary power source.

36. An electronic timepiece including:

a secondary power source supplying a power source for driving;

a time keeping unit driven by said secondary power source; and

a voltage detecting device according to claim 1.

37. An electronic timepiece including:

a secondary power source supplying a power source for driving;

a time keeping unit driven by said secondary power source; and

a battery remaining amount detecting device according to claim 28.

38. An electronic device including:

a secondary power source supplying a power source for driving;

a driven unit driven by said secondary power source; and

a voltage detecting device according to claim 1.

39. An electronic device including:

a secondary power source supplying a power source for driving;

a driven unit driven by said secondary power source; and

a battery remaining amount detecting device according to claim 28.

40. A method for detecting a voltage of a secondary power source comprising steps of:

detecting whether a rapid charging is effected in said secondary power source or not;

outputting as a detection voltage, when said rapid charging is not detected, a detected voltage having a correlation to an amount of a stored electricity of said secondary power source, and outputting as said detection voltage, when said rapid charging is detected, a corrected voltage in which a correction voltage corresponding to an apparent boosted voltage generated in said secondary power source due to said rapid charging is cancelled from said detected voltage; and

outputting a voltage detection result signal, based on said detection voltage.

41. The method as claimed in claim 40, wherein said method further comprises a step of comparing said detection object voltage obtained in said outputting a detection voltage step with a predetermined reference voltage to discriminate a remaining capacity of said secondary power source.