Abstract: It is aimed at stably implementing a protection function of a secondary battery mainly under software control and providing a battery pack characterized by a reduced circuit installation area, parts costs, and power consumption. An AD converter outputs a voltage value between a positive electrode and a negative electrode of a secondary battery. Based on the voltage value, a microcontroller determines a state of the secondary battery out of overcharge, normal operation, and over-discharge states. According to the determined state, the microcontroller controls operations of a discharge current cutoff means and a charge current cutoff means via a FET driver. When it is determined that the secondary battery is placed in an overcurrent state based on the charge and discharge current size of the secondary battery, an overcurrent detection circuit enables the discharge current cutoff means to be a cutoff state in preference to control by the microcontroller.

Abstract: A battery pack which stably implements a protection function of a secondary battery mainly under software control and reduces a circuit installation area and parts costs. The battery pack has a discharge current cutoff means and a charge current cutoff means for selectively cutting off discharge and charge currents of the secondary battery. The battery pack has a protection process means for controlling operations of the discharge current cutoff means and the charge current cutoff means in accordance with an inter-electrode voltage between positive and negative electrodes of the secondary battery. The battery pack executes an initialization process for the protection process means at a timing when a power supply voltage supplied to the protection process means reaches lowest voltage to start the protection process means.

Abstract: It is aimed at stably implementing a protection function of a secondary battery mainly under software control and providing a battery pack characterized by a reduced circuit installation area, parts costs, and power consumption. An AD converter outputs a voltage value between a positive electrode and a negative electrode of a secondary battery. Based on the voltage value, a microcontroller determines a state of the secondary battery out of overcharge, normal operation, and over-discharge states. According to the determined state, the microcontroller controls operations of a discharge current cutoff means and a charge current cutoff means via a FET driver. When it is determined that the secondary battery is placed in an overcurrent state based on the charge and discharge current size of the secondary battery, an overcurrent detection circuit enables the discharge current cutoff means to be a cutoff state in preference to control by the microcontroller.

Abstract: It is aimed at providing a battery pack which stably implements a protection function of a secondary battery mainly under software control and reduces a circuit installation area and parts costs. The battery pack has a discharge current cutoff means and a charge current cutoff means for selectively cutting off discharge and charge currents of the secondary battery. The battery pack has a protection process means for controlling operations of the discharge current cutoff means and the charge current cutoff means in accordance with an inter-electrode voltage between positive and negative electrodes of the secondary battery. The battery pack executes an initialization process for the protection process means at a timing (T42) when a power supply voltage supplied to the protection process means reaches lowest voltage Vpor to start the protection process means.