Fast voltage control scheme with adaptive voltage control steps and temporary reference voltage overshoots for dynamic voltage and frequency scaling

We have developed a voltage control scheme to reduce control time using a delay monitor and step-by-step supply-voltage control. With this scheme, voltage control steps are adaptively controlled, and there are temporary overshoots in the reference voltage. Experimental results with a 65-nm CMOS device indicate that the adaptive voltage control steps successfully reduce the voltage control time by about 35 % over that with fixed step. Simulation results indicate that temporary reference voltage overshoots reduce control time by more than 50%. The combination of these schemes is also effective for control time reduction.