dunc@eecg.toronto.edu (Duncan Elliott) (08/05/89)
Electrical Engineering Computer Group Cider Seminar Series Sigma-Delta Converters by Richard Schreier Electrical Engineering Electronics Group University of Toronto Time: Friday, Aug. 11, 1989, 12:05 --- Place: GB 220 In academia they are called Sigma-Delta converters. In audio land, they are known as oversampled converters. What they are is a nifty way to build both DACs and ADCs and are presently the best bet for achieving the 18-bit linearity expected by digital audio. At the heart of a sigma-delta converter is a coarse converter, operated many times faster than the Nyquist rate, and a very good low-pass filter. The structure of the converter is such that the quantization noise gets reduced in the band of interest. One of the amazing things about these converters is that this configuration yields a low sensitivity to analog component errors. Another is that the converter is inherently linear. In this talk I will analyze a simple sigma-delta modulator, show how to synthesize, in theory, a converter of any order, and then present some results from my work. Questions will be heartily welcomed. Answers even more so. -- Duncan Elliott, Dept. EE, University of Toronto, Toronto, Canada M5S 1A5 dunc@eecg.toronto.edu dunc@eecg.utoronto.ca uunet!utai!eecg!dunc LAT: 43 39' 35.9"N LON: 79 23' 41.7"W ELEVATION: 349.30 VE3PKD