Patent ID: 8594605

Claim:
A semiconductor integrated circuit comprising: a filter circuit; a cutoff frequency calibration circuit which gives a cutoff frequency adjustment result as a signal for adjusting cutoff frequency of the filter circuit to the filter circuit; and a Q-factor calibration circuit which gives a Q-factor adjustment signal as a signal for adjusting a Q factor of the filter circuit to the filter circuit on the basis of an output of the filter circuit, wherein the cutoff frequency calibration circuit can adjust the cutoff frequency of the filter circuit to a desired value by adjusting a capacitance component of the filter circuit, and wherein, after adjustment of the cutoff frequency of the filter circuit by the cutoff frequency calibration circuit, the Q-factor calibration circuit can adjust the Q factor of the filter circuit to a desired value by adjusting, a resistance component of the filter circuit, wherein the filter circuit is a low-pass filter which outputs a signal of a result of cutting off a component of a frequency higher than a predetermined frequency from an input signal, and wherein the cutoff frequency calibration circuit detects an error of the capacitance component by time integration using at least any one of charging and discharging of the capacitance component of the low-pass filter and, on the basis of a detection result of the error, can compensate the error of the capacitance component.