Patent ID: 7936293
Filing Date: 2011-05-03
Classification: H03M

Abstract:
1. A delta-sigma modulator comprising: a higher-order loop filter having a plurality of internal stages and receiving an analog input signal; a 1-bit quantizer for making a decision as to whether output of the higher-order loop filter is positive or negative with respect to an analog reference potential, and for outputting a first output signal Y a first feedback component for carrying out D/A conversion of the first output signal Y a 1.5-bit quantizer for making a decision that an output value of a prescribed internal stage of the plurality of the internal stages, inclusive of the polarity of the output value, exceeds a predetermined reference value, and for outputting a second output signal Y a second feedback component for carrying out D/A conversion of the second output signal Y an operational unit for generating a 1-bit PDM signal Y by performing operations on the first output signal Y