Input Vector Reordering for Leakage Power Reduction in FPGAs

In this paper, a leakage power reduction technique for field-programmable gate arrays (FPGAs) is proposed based on the state dependency property of leakage power. A pin reordering algorithm is proposed, where the subthreshold and gate leakage power components are taken into consideration to find the lowest leakage state for the FPGA pass-transistor multiplexers in the logic and routing resources without incurring any physical or performance penalties. The newly developed methodology is applied to several FPGA benchmarks, and an average leakage savings of 50.3% is achieved in a 90-nm CMOS process. Moreover, a modified version of the methodology is implemented to improve the performance of the final design, and again, considerable leakage power savings are achieved. Furthermore, the methodology is extended to find the lowest leakage states for several future predictive Berkeley CMOS technologies.