Generating highly-routable sparse crossbars for PLDs

Abstract

A method for evaluating and constructing sparse crossbars which are both area efficient and highly routable is presented. The evaluation method uses a network flow algorithm to accurately compute the percentage of random test vectors that can be routed. The construction method attempts to maximize the spread of the switch locations, such that any given subset of input wires can connect to as many output wires as possible. Based on Hall's Theorem, we argue that this increases the likelihood of routing.