SEMICONDUCTOR INTEGRATED CIRCUIT, PACEMAKER PULSE DETECTION APPARATUS, AND PACEMAKER PULSE DETECTION METHOD

An acquisition circuit obtains an electrocardiogram waveform on which a pulse signal of a pacemaker is superimposed. A detector circuit performs a filtering process on the electrocardiogram waveform at a cutoff frequency that is determined according to a control signal, and detects a pulse signal on the basis of the result of the filtering process. A control circuit detects, a plurality of times, an occurrence start time of a QRS complex from the electrocardiogram waveform obtained by the acquisition circuit, and detects a QRS duration, and then determines a predicted occurrence start time of the next QRS complex on the basis of the detected occurrence start times of the QRS complexes, and supplies, to the detector circuit, a control signal for instructing to increase the cutoff frequency from a first value to a second value during a period based on the QRS duration from the predicted occurrence start time.