New structural concepts for low-cost high-speed A/D converters

Two new circuit techniques for A/D conversion are described. They provide high speed at moderate hardware complexity. The parallel conversion structure is combined with the cyclic structure in a manner that eliminates the need for analog-signal subtraction and/or digital to analog conversion so as to minimize speed loss due to cycling. Besides, using the same hardware for two or more cycles insures a small comparator/bit ratio, a fact which makes both techniques easy to manufacture over a single silicon die