Seiko Instruments Inc

Takakazu Ozawa

Atsushi Sakurai

Kiyoshi Yoshikawa

Yoshihisa Tange

Provided are a battery protection IC adaptable to any number of batteries connected in series without increasing a breakdown voltage thereof, and a battery device including the battery protection IC mounted thereon. A charge control signal input terminal and a discharge control signal input terminal of one battery protection IC are provided with a clamp circuit (), and hence an output driver () of another battery protection IC connected to those terminals is not applied with a voltage equal to or higher than a breakdown voltage. Accordingly, the breakdown voltage of the battery protection IC is not required to be high.

Battery protection IC and battery device

Provided is a battery state monitoring circuit which is capable of preventing a discharge leak current from a battery so as to eliminate a load conventionally imposed on a user, including: a battery state detector circuit that detects a state of the battery based on a voltage of the battery; a transmitting terminal that transmits battery state information indicative of the state of the battery to an outside; a receiving terminal that receives battery state information of another battery from the outside; a transistor that is used for transmitting the battery state information, and has any one of two terminals except for a control terminal connected to the transmitting terminal; and a diode that is connected in a direction opposite to a direction of a parasitic diode disposed between the two terminals of the transistor, the diode being disposed between the transmitting terminal and one terminal of the transistor.

Growing community of inventors

Chiba, Japan

Takakazu Ozawa