Rank-order filtering in analog VLSI

An analog VLSI circuit that rank-order filters an array of analog inputs is presented. To prevent the rank-order filtering elements from consuming a prohibitively large amount of space on the input plane, ranks are computed only partially in parallel. This semi-parallel implementation of rank-order filtering is based on the inhibition of winner-take-all circuit elements that have been presented previously in the literature. These rank-order filtering elements are capable of ranking an unlimited number of analog inputs.