SEMICONDUCTOR DEVICE AND METHOD FOR MEASURING BATTERY VOLTAGE

摘要

PROBLEM TO BE SOLVED: To provide a semiconductor device and a method for measuring a battery voltage with which it is possible to suppress a measurement error due to parasitic capacitance that occurs in measuring a battery voltage.SOLUTION: There is inputted to a buffer amplifier BAMP1 a voltage on high-voltage side of a battery cell Vc for which a battery voltage is measured. There is inputted to a buffer amplifier BAMP2 a voltage on low-voltage side of a battery cell Vc to be measured other than a battery cell Vc1 at the bottom. When measuring the battery voltage of the battery cell Vc1, a switch SW_G switches the voltage inputted to an amplifier AMP1 from the voltage outputted from the buffer amplifier BAMP2 to a reference voltage VSS. A switch SW0_1 switches the voltage inputted to the buffer amplifier BAMP1 from the voltage on high-voltage side of the battery cell Vc for which a battery voltage is measured to the reference voltage VSS. A semiconductor device 10 is provided with a switch SW0_2 for switching the voltage inputted to the buffer amplifier BAMP2 to the reference voltage VSS.SELECTED DRAWING: Figure 1