Adaptive Voltage Scaling in a Dynamically Reconfigurable FPGA-Based Platform

Power is an important issue limiting the applicability of Field Programmable Gate Arrays (FPGAs) since it is considered to be up to one order of magnitude higher than in ASICs. Recently, dynamic reconfiguration in FPGAs has emerged as a viable technique able to achieve power and cost reductions by time-multiplexing the required functionality at runtime. In this article, the applicability of Adaptive Voltage Scaling (AVS) to FPGAs is considered together with dynamic reconfiguration of logic and clock management resources to further improve the power profile of these devices. AVS is a popular power-saving technique in ASICs that enables a device to regulate its own voltage and frequency based on workload, fabrication, and operating conditions. The resulting processing platform exploits the available application-dependent timing margins to achieve a power reduction up to 85% operating at 0.58 volts compared with operating at a nominal voltage of 1 volt. The results also show that the energy requirements at 0.58 volts are aproximately five times lower compared with nominal voltage and this can be explained by the approximate cubic relation of static energy with voltage and the fact that the static component dominates power consumption in the considered FPGA devices.