Patent ID: 8111178

Claim:
A calibration method for a capacitor array including a plurality of capacitor components each having a first node and a second node, first nodes of the capacitor components being coupled to each other, the calibration method comprising: coupling a first node of a calibration capacitor component with a known capacitance value to the first nodes of the capacitor components; coupling a first reference voltage to a second node of a specific capacitor component under test selected from the plurality of capacitor components, comparing the voltage level at the first nodes of the capacitor components with a predetermined voltage to generate a first comparison result and tuning a first test voltage supplied to the second node of the calibration capacitor component according to the first comparison result until the first comparison result indicates that the voltage level at the first nodes of the capacitor components is substantially equal to the predetermined voltage; coupling a second reference voltage different from the first reference voltage to the second node of the specific capacitor component under test, comparing the voltage level at the first nodes of the capacitor components with the predetermined voltage to generate a second comparison result and tuning a second test voltage supplied to the second node of the calibration capacitor component according to the second comparison result until the second comparison result indicates that the voltage level at the first nodes of the capacitor components is substantially equal to the predetermined voltage; and determining a capacitance indication value corresponding to the specific capacitor component under test according to the first test voltage and the second test voltage.