Abstract: An increase in the load of the booster circuit may be suppressed, and the voltage measurement accuracy may be improved. A battery monitoring IC of a battery monitoring system includes a first buffer amplifier and a second buffer amplifier driven by a power supply voltage or a boost voltage and having an input terminal connected to one terminal of any one of battery cells of an assembled battery. The control part selects the battery cell to be connected to the input terminals of the first and second buffer amplifiers. The control part switches a voltage for driving the first and second buffer amplifiers to the boost voltage when an upper battery cell is selected, and switches the voltage for driving the first and second buffer amplifiers to the power supply voltage when a battery cell other than the upper battery cell is selected.

Abstract: The present invention provides a clamp circuit including, a switching section including first and second switching elements connected parallel between a current supply source and a clamp capacitor; a first control section that controls the first switching element to connect the current supply source and the clamp capacitor, when the voltage of an input signal input through the clamp capacitor is lower than a first reference voltage; and a second control section that stores voltage information based on the input signal when the voltage of the input signal is lower than a second reference voltage, and that controls the second switching element to connect the current supply source and the clamp capacitor for a period predetermined based on the voltage information, when the input signal is equal to or higher than the first reference voltage.

Abstract: The present invention provides a clamp circuit including, a switching section including first and second switching elements connected parallel between a current supply source and a clamp capacitor; a first control section that controls the first switching element to connect the current supply source and the clamp capacitor, when the voltage of an input signal input through the clamp capacitor is lower than a first reference voltage; and a second control section that stores voltage information based on the input signal when the voltage of the input signal is lower than a second reference voltage, and that controls the second switching element to connect the current supply source and the clamp capacitor for a period predetermined based on the voltage information, when the input signal is equal to or higher than the first reference voltage.