Dithering Techniques for Delta-Sigma Modulator Based Digital-to-Analog Converters

University Of California-Los Angeles, Los Angeles CA

Investigators

Abstract

The objective of this research is to develop signal processing theories and techniques to combat circuit impairments such as sizing errors and nonlinear device behavior in practical, integrated, delta-sigma modulator based digital-to-analog converters (DACs). These DACs are vital components in many electronic systems including radio transceivers and audio and video equipment. The proposed approach is to use random dithering of the delta-sigma modulator input signal to condition the statistics of its quantization noise; such conditioning will reduce the DAC's sensitivity to the aforementioned circuit errors. The expected outcome of the research is high performance DACs that are easy to design and sufficiently robust to offer high fabrication yields, unlike traditional DACs that are designed using extensive simulation-based optimization strategies. The intellectual merit of the research is that it presents a fundamentally different approach to combating circuit errors in DACs: an approach that does not depend on circuit optimization but applies signal processing techniques to improve circuit performance. Furthermore, the research aims at realigning theoretical data converter research to address relevant problems faced by practical circuit designers. The broader impacts of the project are two-fold. First, it addresses the problem of building high performance digital-to-analog converters that are crucial to the growth of the electronics industry. Second, it will encourage students from underrepresented groups to take up advanced engineering careers by providing graduate students and summer interns recruited specifically from such groups to work on the proposed project under close supervision of the PI.