Patent ID: 7411527

Claim:
A noise shaping quantizer comprising: a first noise shaping quantization unit that applies a first noise shaping operation on an input signal; said first noise shaping quantization unit includes: a local quantizer that quantizes the input signal and outputs an output signal; an error accumulator that accumulates at least a part of a value based on the output signal based on at least one of a value based on the input signal and a value based on the output signal, outputs the remaining part, and outputs at least a part of the accumulated value which is based on the output value based on at least one of a value based on another input signal and a value based on another output signal at a later clock; a subtractor to which the input signal and the output of said error accumulator are inputted; a delay element to which the output of said subtractor is inputted; and a first adder that adds the output of said delay element and an input from external, and outputs the sum to said local quantizer.