AUTOMATIC DEEP DISCHARGE CIRCUIT FOR RECHARGEABLE BATTERIES

摘要

An automatic discharge circuit (20) is located inside a cellular telephone to prevent memory effects from occurring in a rechargeable battery (14). When activated, the discharge circuit (20) is coupled across the rechargeable battery (14) deeply discharging the battery (14) to a sufficiently low level to prevent memory effects. A control circuit (16) located in the cellular telephone activates the discharge circuit (20) when the battery output power level is below a minimal power level necessary for conducting normal operations in the electrical device. The deep discharge takes place after the battery charge has already fallen below a minimum power level required to effectively conduct a cellular telephone call. However, the battery (14) still has sufficient charge to power logic circuitry in the telephone. Thus, the discharge circuitry can automatically discharge the battery (14) without effecting normal telephone operations.