Patent ID: 6201490
Filing Date: 2001-03-13
Classification: H03M

Abstract:
A D/A conversion apparatus, comprising:an input terminal that receives input digital data;a level converting device that converts the input digital data with different conversion factors, to generate a plurality of digital data having different levels;an output device that selects one of the plurality of digital data generated by said level converting device, depending upon a digital input level of the input digital data, to generate selected digital data, while attenuating the other digital data to be lower than a predetermined noise level, to generate attenuated digital data;a plurality of D/A converting devices that convert respective selected digital data generated by said output device, into corresponding analog signals;a re-converting device that converts a level of each of the analog signals generated by said D/A converting devices, into an original level, based on a corresponding one of the conversion factors with which the input digital data is converted by said level converting device to generate re-converted analog signals;an adding device that adds the re-converted analog signals generated by said re-converting device; andan attenuating device that attenuates, in an input stage of said adding device, medium-to-high frequency components of at least one of the analog signals generated by at least one of said D/A converting devices that receives the attenuated digital data, said at least one of the analog signals corresponding to digital data obtained by converting the input digital data with a smaller conversion factor than that of the selected digital data generated by said output device.