Converter

approved: A delta-sigma digital-to-analog data converter is a signal conversion system that takes a digital signal as its input and produces an analog signal as its output. A digital signal is converted to an analog signal by increasing the digital clock rate to a value which is much higher than its corresponding Nyquist rate. Then, using a delta-sigma modulator we reduce the wordlength. Finally, the signal is converted to its analog form. This kind of converter is called a delta-sigma digital-to-analog converter. It introduces significant out-of-band noise. An analog post-filter serves to remove the large out-of-band noise; that is, to smooth the sampled output of the D / A circuit. A new smoothing filter was designed especially for dual-quantization delta-sigma digital-to-analog converters. It reduces the noise slightly above the band of interest as well as the high frequency noise by using two switched-capacitor filter stages and a continuous-time filter. Redacted for Privacy The thesis is divided into four chapters. Chapter 1 is an introduction to the general concept of oversampling D/A converters and to dual-quantization delta-sigma D/A converters. Chapter 2 describes the design procedures used in the design of a post-filter for dual-quantization delta-sigma D/A converter. Chapter 3 deals with the imperfections in switched-capacitor circuit of the post-filter. Finally, chapter 4 summarizes the properties of the post-filter and proposes some future research work. The Design of a Postfilter for a Delta-Sigma Digital-to-Analo