Patent ID: 7235949

Claim:
A battery capacity detection apparatus for detecting the remaining capacity in a battery installed in a device capable of operating in either a high load mode or a low load mode, comprising: a microprocessor for determining if the device is in the low load mode or in the high load mode of operation; an operating mode detection circuit for detecting the analog discharge voltage of the battery; an A/D converter for converting the detected analog discharge voltage of said battery into a digital output signal; and a comparator for comparing the detected analog discharge voltage of said battery with a specific reference voltage; wherein when said microprocessor determines that the operating mode of the device is the low load mode said microprocessor calculates the battery capacity remaining in said battery directly from said digital output signal from the A/D converter and wherein when said microprocessor determines that the operating mode of the device is in the high load mode said microprocessor calculates the battery capacity remaining in said battery from an output of said comparator based upon an interrupt process of the microprocessor.