An object is to provide a stable delta-sigma modulator having good microlevel signal reproducibility and capable of outputting a 1-bit PDM signal with a low oversampling ratio of about 64 times at a high duty ratio of 90% or more. The delta-sigma modulator has a higher-order loop filter; a first 1-bit quantizer for making a decision as to the output of the higher-order loop filter; a first feedback component for feeding the first output signal back to the input stage of the higher-order loop filter; a second 1.5-bit quantizer for making a decision as to the output absolute value of an internal stage to be monitored; a second dynamic feedback component for feeding a second output signal back to the input stage of the higher-order loop filter; and an operational unit for producing a 1-bit PDM signal Y by performing operation on the first output signal and second output signal.