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An electronic circuit and a method for accurately measuring intermittent current pulses supplied by a storage battery to energize a load. In the preferred embodiment, an analog integrator accumulates current pulses in response to a voltage drop across a sense resistor that is connected in series bet

An electronic circuit and a method for accurately measuring intermittent current pulses supplied by a storage battery to energize a load. In the preferred embodiment, an analog integrator accumulates current pulses in response to a voltage drop across a sense resistor that is connected in series between the storage battery and the load. The voltage drop is proportional to the flow of current from the battery through the load. The output of the integrator is filtered with a low pass filter to block high frequency noise, and the output of the filter is coupled to an analog to digital (A/D) converter that transforms the filtered analog signal into a corresponding digital signal. The output of the A/D converter is supplied to a port of a processor. The processor provides a signal to actuate a reset switch coupled across the integrator. When closed at the end of each integration time period, this switch zeroes the output of the analog integrator. Additionally, the processor recalibrates the circuit at predefined time intervals to determine for leakage currents for improving the accuracy with which the measurement of the flow of current from the battery is determined. In the preferred embodiment, the processor samples the output of the A/D converter every 100 milliseconds. Typically, the calibration procedure is performed every 15 minutes (while the load is energized from an AC source). This measurement circuit is part of a battery management system that preferably also includes a charge circuit for recharging the battery.

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[ The invention in which an exclusive right is claimed is defined by the following:] [1.] An electronic circuit for measuring a total electrical current that is discharged from a battery to energize a load, comprising:(a) a resistor having an end that is coupled in series with the load and the batte

[ The invention in which an exclusive right is claimed is defined by the following:] [1.] An electronic circuit for measuring a total electrical current that is discharged from a battery to energize a load, comprising:(a) a resistor having an end that is coupled in series with the load and the battery so that the electrical current supplied by the battery to energize the load flows through the resistor, a voltage developed across the resistor indicating a magnitude of the electrical current;(b) an integrator having an input that is coupled to the resistor to sense the voltage across the resistor, said integrator producing a signal at an output of the integrator that is indicative of a total electrical current supplied to energize the load over a time period and is thus indicative of a power consumed by the load over said time period, a switch being provided to reset the output of the integrator at an end of the time period, to enable the integrator to integrate the current supplied to energize the load for successive time periods;(c) an analog-to-digital converter coupled to the output of the integrator for receiving the signal, the analog-to-digital converter digitizing the signal to produce a corresponding digital value at an output of the analog-to-digital converter; and(d) a processor coupled to the output of the analog-to-digital converter, said processor producing the reset signal that is coupled to the integrator to reset it at the end of each time period and accumulating successive digital values produced by the analog-to-digital converter over successive time periods to determine the total current discharged by the battery to energize the load.