Modern FPGA architectures from Altera and Xilinx have shifted away from allowing multiple drivers to connect to each interconnect wire. This work advocates the need for this shift to single-driver wiring by investigating the necessary architectural and circuit design changes. When single-driver wiring is used, area improves by 25%, delay improves by 9%, and area-delay improves by 32% compared to bidirectional wiring. Wiring capacitance is reduced by 37% due to reduced switch loading and physical wire length shrinkage. Furthermore, it is shown that larger circuits tend to realize larger savings. No significant CAD tool changes are needed.
['Guy G. Lemieux', 'Edmund Lee 0002', 'Marvin Tom', 'Anthony J. Yu']
Directional and single-driver wires in FPGA interconnect