Patent ID: 6476742
Filing Date: 2002-11-05
Classification: H03M

Abstract:
An evaluation system for a D-A converter comprising:a pattern generator for generating a sine wave pattern in the form of a digital signal; a timing controller for generating a clock which is used in supplying the sine wave pattern to a D-A converter under test; an A-D converter having a higher accuracy of conversion than the D-A converter and operative to convert an analog signal outputted from the D-A converter to a digital signal; a waveform memory for storing and accumulating a digital signal outputted from the A-D converter; instantaneous amplitude calculation means for taking out a digital signal stored in the waveform memory therefrom and determining an instantaneous amplitude; interleave signal producing means for receiving the instantaneous amplitude and the amplitude of the sine-wave as its inputs and forming an interleave signal in which the instantaneous amplitude and the amplitude of the sine wave are interleaved; and digital moving differentiator means for receiving the interleave signal as its input and calculating a moving difference.