Focus on What is Needed: Area and Power Efficient FPGAs Using Turn-Restricted Switch Boxes

Field-Programmable Gate Arrays (FPGAs) employ a significant amount of SRAM cells in order to provide a flexible routing architecture. While this flexibility allows for a rather easy realization of arbitrary functionality, the respectively required cells significantly increase the area and power consumption of the FPGA. At the same time, it can be observed that full routing flexibility is frequently not needed in order to efficiently realize the desired functionality. In this work, we are proposing an FPGA realization which focuses on what is needed and realizes only a subset of the possible routing options using what we call Turn-Restricted Switch-Boxes. While this may yield a slight decrease in the run-time performance of the realized functionality, it allows for substantial improvements with respect to area and power consumption. In fact, experimental evaluations confirm that area and power can be reduced by more than 40% and 60%, respectively, in the best cases. The performance overhead is negligible (up to 3%), on average.