BATTERY MONITORING SYSTEM AND SEMICONDUCTOR DEVICE

摘要

PROBLEM TO BE SOLVED: To prevent a current from flowing to a discharge circuit from battery cells through an electro-static protection circuit in a normal operation.SOLUTION: A high-potential side of each of battery cells C and a cell-voltage measurement circuit 22 are connected via low-pass filters LPF (LPF 1 to LPFn) and cell input terminals V (V1 to Vn). The high-potential side of the battery cell Cn is connected to a terminal Vcc_vn via a low-pass filter LPFvcc_vn and is connected to a power-supply terminal Vcc via a low-pass filter LPFvc. The cell-voltage measurement circuit 22 is connected to the power-supply terminal Vcc and is not connected to the terminal Vcc_vn. An inter-power-supply ESD protection circuit 24 is connected between the terminal Vcc_vn and a power-supply terminal Vss. ESD protection diodes ESD are connected to the cell input terminals V, and discharge high-voltage noise due to electrostatic discharge and the like to the terminal Vcc_vn or the power-supply terminal Vss.