Patent ID: 8878555

Claim:
A capacitance measurement device for measuring the capacitance of a measured capacitor comprising: a charging control unit for charging the measured capacitor; a discharging control unit for discharging the measured capacitor; a first switch coupled between the measured capacitor and the charging control unit, for controlling a connection between the measured capacitor and the charging control unit according to a first switching signal; a second switch coupled between the measured capacitor and the discharging control unit, for controlling a connection between the measured capacitor and the discharging control unit according to a second switching signal; a first analog-to-digital (A/D) converter coupled to the measured capacitor, for converting a voltage signal on the measured capacitor into a first signal; and a duty cycle detecting circuit coupled to the measured capacitor, for converting the voltage signal on the measured capacitor into a count value that represents the capacitance of the measured capacitor and outputting the count value to a processing unit; wherein at least one of the charge control unit and the discharge control unit sets a discharge/charging capacity for discharging/charging the measured capacitor according to the first signal.