FPGA power Reduction by mux based clock gating considering a logic architecture

Abstract

Guarded evaluation is a power reduction technique that involves identifying subcircuits (within a larger circuit) whose inputs can be held constant (guarded) at specific times during circuit operation, thereby reducing switching activity and lowering dynamic power. The concept is rooted in the property that under certain conditions, some signals within digital designs are not “observable” at design outputs, making the circuitry that generates such signals a candidate for guarding. Guarded evaluation has been demonstrated successfully for applicationspecific integrated circuits (ASICs); in this paper, we apply the technique to field-programmable gate arrays (FPGAs). In ASICs, guarded evaluation entails adding additional hardware to the design, increasing silicon area and cost. Here, we apply the technique in a way that imposes minimal area overhead by leveraging existing unused circuitry within the FPGA