摘要 |
In a battery voltage monitoring device including a battery voltage monitoring IC coupled to a plurality of unit cell groups configuring an assembled battery by being serially coupled in multiple stages and measuring voltage of each of the unit cells and a system control unit controlling the whole, communication between the system control unit and the battery voltage monitoring ICs is realized in consideration of fail-safe. The system control unit and the plurality of battery voltage monitoring ICs are coupled to each other by a communication path using a daisy chain. The battery voltage monitoring IC has a placement setting pin designating, by a binary code, a unit cell group to which the IC is coupled, in the unit cell groups. When it is detected that the Hamming distance between the code indicative of coupling to a group of the highest potential or a group of the lowest potential and a state actually set in the placement setting pin is 1, occurrence of failure such as line disconnection, short-circuit, or the like in the placement setting pin is determined, and an output to a communication path is interrupted by being set to high impedance. |