Interconnect architecture for field programmable gate array

Abstract

An FPGA architecture is provided which uses logic unit output lines of more than one length and provides extension lines to increase the reach of a logic unit output line. The architecture allows extremely fast connections between one logic unit and another. Also, all logic unit output lines drive about the same number of buffered programmable interconnection points (PIPs) so that the signal delay between one logic unit and the next can be predicted regardless of the functions and routing which have been selected by a user. The frequency of PIPs decreases as distance from the originating logic unit increases. This has the benefit of cooperating with software which tends to place interconnected logic in close proximity. The architecture is preferably implemented with a tile layout with one logic unit in each tile, and logic unit input and output lines extending through several tiles. Thus one tile boundary is like another and there is minimum hierarchy.