الفهرس | Only 14 pages are availabe for public view |
Abstract In this work a circuit technique for a cyclic - parallel converter structure is pressented. The suggested technique has significant speed advantage over the conventional cyclic approach as well as simpler hardware, and hence lower cost, compared to the all-parallel approach. Besides, the technique has potential development in both high-speed and higher resolution directions. The development of single chip high-speed flash converters will make the cyclic-parallel type of converters, described here attactive by virtue of increased resolution with lower part count and cost. In addition, the capacitance driving problem of the all-parallel approach is partially eliminated. The idea is based on generating the output word sequentially in an ordinary parallel quantizer in several cycles. In each cycle aproper reference is applied to the resistor string of the parallel converter. The obtained digital output of the preceeding cycles is applied to a high-speed D/A converter. The resulting analog output is then subtracted from the applied analog signal and used as a new input of the next cycle. Chapter ”I” gives abackground about analog to digital converters and their applications. Chapter II describes different methods for analog-to-digital converter realizations. Chapter III presents and analyzes an analog-to-digital converter-circuit based on the new technique. Experimental results of this new technique are given and analysed in chapter Iv. |