Means for detecting the integrated value of current flow, a means for detecting the value of current flow and a battery pack employing those means

• US 6,285,164 B1
• Filed: 11/13/2000
• Issued: 09/04/2001
• Est. Priority Date: 03/31/1998
• Status: Expired due to Fees

• Current Assignee: Hitachi, Ltd., Hitachi Maxell Limited (Hitachi, Ltd.), Hitachi ULSI Systems Company Limited (Hitachi, Ltd.)
• Original Assignee: Hitachi, Ltd., Hitachi Maxell Limited (Hitachi, Ltd.), Hitachi ULSI Systems Company Limited (Hitachi, Ltd.)
• Inventors: Tanaka, Shinji, Yamaguchi, Takeshi, Noda, Masaru, Tsuchiya, Mitsunori, Takeuchi, Takashi
• Primary Examiner(s): Wong, Peter S.
• Assistant Examiner(s): LUK, LAWRENCE W
• Application Number:
  US09/709,431
• Time in Patent Office: 295 Days
• Field of Search: 320/132, 320/130, 320/134, 320/136, 320/152, 320/156, 324/426, 324/427, 324/428
• US Class Current: 320/132
• CPC Class Codes: G01R 31/3648 comprising digital calculation means, e.g. for performing an algorithm
• CPC Class Codes: G01R 31/3828 using current integration

Abstract

An apparatus for detecting an integrated value of current flow. The apparatus includes an integrator having an integration capacitor, to which a current sensor voltage is inputted, for outputting an output voltage corresponding to an integrated value of the current sensor voltage, and a resetting circuit for clearing integration electric charges accumulated in the integration capacitor to reset the integrator when the output voltage has reached an upper threshold value or a lower threshold value. The apparatus also includes a counter for counting the number of resets of the integrator in an upper direction or in a lower direction, and a connection-polarity inverting circuit for inverting a polarity of inputting of the current sensor voltage to the integrator, a polarity of connecting of the integration capacitor to the integrator and a counting direction of the counter, alternatively, at a regular time interval and synchronously. An integrated value of current flow is obtained on the basis of a count value of the counter.

Claims

1. An apparatus for detecting an integrated value of current flow, comprising:

an integrator including an integration capacitor, to which a current sensor voltage is inputted, for outputting an output voltage corresponding to an integrated value of said current sensor voltage;

a resetting circuit for clearing integration electric charges accumulated in said integration capacitor to reset said integrator when said output voltage has reached an upper threshold value or a lower threshold value;

a counter for counting the number of resets of said integrator in an upper direction or in a lower direction; and

a connection-polarity inverting circuit for inverting a polarity of inputting of said current sensor voltage to said integrator, a polarity of connecting of said integration capacitor to said integrator and a counting direction of said counter, alternatively, at a regular time interval and synchronously;

wherein an integrated value of current flow is obtained on the basis of a count value of said counter.

2. An apparatus for detecting an integrated value of current flow, comprising:

an integrator including an integration capacitor, to which a current sensor voltage is inputted, for outputting an output voltage corresponding to an integrated value of said current sensor voltage;

a resetting circuit for clearing integration electric charges accumulated in said integration capacitor to reset said integrator when said output voltage has reached an upper threshold value or a lower threshold value;

a counter for counting the number of resets of said integrator in an upper direction or in a lower direction; and

a connection-polarity inverting circuit for inverting a polarity of inputting of said current sensor voltage to said integrator and a polarity of connecting of said integration capacitor to said integrator, alternatively, at a regular time interval and synchronously;

wherein a counting direction of said counter is controlled on the basis of a combination of which of said upper and lower threshold values of said output voltage of said integrator has been reached and a status of the polarity of said connection-polarity inverting circuit; and

wherein an integrated value of current flow is obtained on the basis of a count value of said counter.

3. An apparatus for detecting an integrated value of current flow, comprising:

a current sensor resistor inserted in series with a current path of a battery;

an integrator including an integration capacitor, to which a current sensor voltage detected by said current sensor resistor is inputted, for outputting an output voltage corresponding to an integrated value of said current sensor voltage;

a resetting circuit for clearing integration electric charges accumulated in said integration capacitor to reset said integrator when said output voltage has reached an upper threshold value or a lower threshold value;

a counter for counting the number of resets of said integrator in an upper direction or in a lower direction;

a connection-polarity inverting circuit for inverting a polarity of inputting of said current sensor voltage to said integrator and a polarity of connecting of said integration capacitor to said integrator, alternatively, at a regular time interval and synchronously;

a micro-computer;

a portable information terminal to which an electric power of said battery is supplied through said current sensor resistor; and

communication means through which information is transmitted between said micro-computer and said portable information terminal;

wherein a counting direction of said counter is controlled on the basis of a combination of which of said upper and lower threshold values said output voltage of said integrator has been reached and a status of the polarity of said connection-polarity inverting circuit;

wherein said micro-computer reads out the count value of said counter to calculate a battery energy remainder value; and

wherein said portable information terminal receives data relating to said battery energy remainder value calculated by said micro-computer through said communication means and effects display thereof.

4. An apparatus for detecting an integrated value of current flow, comprising:

a current sensor resistor inserted in series with current path of a battery;

an integrator including an integration capacitor, to which a current sensor voltage detected by said current sensor resistor is inputted, for outputting an output voltage corresponding to an integrated value of said current sensor voltage;

a resetting circuit for clearing integration electric charges accumulated in said integration capacitor to reset said integrator when said output voltage has reached an upper threshold value or a lower threshold value;

a counter for counting the number of resets of said integrator in an upper direction or in a lower direction;

a connection-polarity inverting circuit for inverting a polarity of inputting of said current sensor voltage to said integrator and a polarity of connecting of said integration capacitor to said integrator, alternatively, at a regular time interval and synchronously; and

unit time average current value calculating means for calculating a unit time average current value on the basis of the count value of said counter;

wherein a counting direction of said counter is controlled on the basis of a combination of which of said upper and lower threshold values said output voltage of said integrator has been reached and a status of the polarity of said connection-polarity inverting circuit; and

wherein said unit time average current value calculating means reads out the count values of said counter at predetermined time intervals and divides a difference between the last read count value and the newest read count value by the predetermine time interval, thereby calculating the unit time average current value.

5. A battery pack comprising:

a battery; and

a unit for detecting a value of current flow of said battery or an integrated value of the current flow of said battery;

said unit comprising;

a current sensor resistor inserted in series with a current path of said battery;

an integrator including an integration capacitor, to which a current sensor voltage detected by said current sensor resistor is inputted, for outputting an output voltage corresponding to an integrated value of said current sensor voltage;

a resetting circuit for clearing integration electric charges accumulated in said integration capacitor to reset said integrator when said output voltage has reached an upper threshold value or a lower threshold value;

a counter for counting the number of resets of said integrator in an upper direction or in a lower direction;

a connection-polarity inverting circuit for inverting a polarity of inputting of said current sensor voltage to said integrator and a polarity of connecting of said integration capacitor to said integrator, alternatively, at a regular time interval and synchronously; and

a micro-computer;

wherein a counting direction of said counter is controlled on the basis of a combination of which of said upper and lower threshold values said output voltage of said integrator has been reached and a status of the polarity of said connection-polarity inverting circuit; and

wherein said micro-computer includes calculating means for reading out the count value of said counter to calculate a battery energy remainder value or a unit time average current value.