Patent ID: 6204788
Filing Date: 2001-03-20
Classification: H03M

Abstract:
A digital/analog conversion apparatus comprising:a digital filter for increasing the sampling frequency of an input digital signal by k (k: an integer) times,a noise shaper for carrying out word length limitation by using the output of said digital filter as an input and for changing the frequency characteristic of noise to a predetermined characteristic,a decoder for using the output of said noise shaper as a decoder input and for generating and outputting a row of 1-bit signals wherein ""1"" is assigned to 1-bit signals, the number of which corresponds to the value of said decoder input,a row of 1-bit digital/analog converters for converting the outputs of said decoder into analog signals, andan analog adder for integrating the outputs of said row of 1-bit digital/analog converters, whereinin said row of 1-bit signals, the 1-bit signal position to which value ""1"" is assigned is circulated, and a 1-bit signal at a predetermined position in said row of 1-bit signals is designated as an inhibit bit wherein the assignment of value ""1"" is inhibited so that harmonic distortion included in the outputs of said row of 1-bit digital/analog converters can be reduced.