Delta sigma modulator, as well as receiver device and wireless communication device provided with same

A delta sigma modulator, comprising:

• a filter circuit including integrators connected in cascade and in a plurality of stages, the integrators each including an operational amplifier;
• a quantizer which quantizes an output signal from the filter circuit;
• a first digital-to-analog converter which converts a digital output signal from the quantizer into a first analog signal and feed back the first analog signal to the filter circuit;
• a first addition circuit coupled between an output of the filter circuit and an input of the quantizer, the first addition circuit receiving the output signal from the filter circuit as an input signal, the first addition circuit including at least one passive element, the at least one passive element including a first resistive element;
• and
• a second addition circuit including at least one of a first feedforward circuit connecting an input section of the filter circuit to the input of the quantizer via a second resistive element, a first feedback circuit which feeds back the digital output signal from the quantizer, as a second analog signal, to the input section of the quantizer, or a second feedforward circuit which feeds forward an output signal from at least one of the integrators via at least one passive element,
• wherein the first addition circuit includes a capacitive element serving as the phase compensator and connected in parallel to the first resistive element.

A delta sigma modulator, comprising:

• a filter circuit including at least one integrator having an operational amplifier;
• a quantizer which quantizes an output signal from the filter circuit;
• a first digital-to-analog converter which converts a digital output signal from the quantizer into an analog signal and feed back the analog signal to the filter circuit;
• a first resistive element coupled between an output of the filter circuit and an input of the quantizer;
• a first feedforward circuit connecting an input section of the filter circuit to the input of the quantizer via a second resistive element;
• and
• a capacitive element connected in parallel to the first resistive element, the first resistive element and the capacitive element receiving the output signal from the filter circuit as an input signal.