Speed and voltage selection for GALS systems based on voltage/frequency islands

Due to increasing clock speeds and shrinking technologies, distributing a single global clock signal throughout a chip is becoming a difficult and challenging proposition. In this paper, we address the problem of energy optimal local speed and voltage selection in frequency/voltage island based systems under given performance constraints. Our results show that static voltage and speed assignment can achieve up to 42% savings in total energy for various media and signal processing applications, while application specific dynamic approaches provide up to 44% energy savings in the case of MPEG-2 encoder application, when compared to a single clocked system architecture.