MORAS: An energy-scalable system using adaptive voltage scaling

This paper presents an energy-scalable computing platform for flexible and smart WSN edge applications. The platform comprises a 32-bit OpenRISC processor and two 4KB instruction and data caches on a chip, which can be operated in a wide supply voltage range. Adaptive voltage scaling makes this processor search its minimal operating voltage given a performance prerequisite. Different from many embedded MCU platforms, DRAM is supported here to expend flexibility of programing and data logging. This system on a chip (SoC) was implemented using TSMC 0.18 μm CMOS process, the operating range is from 0.6V, 2.5MHz to 1.2V, 40MHz. Measurements show the SoC achieves 170μW/MHz at 0.6V, offering a cost- and energy-efficient edge design solution.