Patent ID: 8319476

Claim:
A battery state monitoring circuit, comprising: a first voltage monitoring terminal used for connection to a positive terminal of one battery; a second voltage monitoring terminal used for connection to a negative terminal of the battery; a first transmitting terminal; a second transmitting terminal; a first receiving terminal; a second receiving terminal; a control terminal; an overcharge detector circuit which detects whether the battery is in an overcharged state or not, based on a voltage between the first voltage monitoring terminal and the second voltage monitoring terminal to output an overcharge detection signal indicative of the detection result; an overdischarge detector circuit which detects whether the battery is in an overdischarged state or not, based on the voltage between the first voltage monitoring terminal and the second voltage monitoring terminal to output an overdischarge detection signal indicative of the detection result; a cell balance circuit which detects whether the battery needs to be subjected to cell balance control or not, based on the voltage between the first voltage monitoring terminal and the second voltage monitoring terminal to output a cell balance signal indicative of the detection result to the control terminal; an overcharge information communication circuit which transmits an overcharge signal indicative of an overcharged state to an external from the first transmitting terminal when at least one of an overcharge signal indicating whether another battery is in the overcharged state or not, which has been received through the first receiving terminal, and the overcharge detection signal, is indicative of the overcharged state; and an overdischarge information communication circuit which transmits an overdischarge signal indicative of an overdischarged state to an external from the second transmitting terminal when at least one of an overdischarge signal indicating whether another battery is in the overdischarged state or not, which has been received through the second receiving terminal, and the overdischarge detection signal, is indicative of the overdischarged state, wherein the battery state monitoring circuit is configured as one semiconductor device.