Dual Supply Voltages and Dual Clock Frequencies for Lower Clock Power and Suppressed Temperature-Gradient-Induced Clock Skew

Two new clocking methodologies based on supply voltage and frequency scaling are proposed in this paper for lowering the power consumption and the temperature-fluctuation-induced skew without degrading the clock frequency. The clock signal is distributed globally at a scaled supply voltage with a single clock frequency with the first clocking methodology. Alternatively, dual supply voltages and dual signal frequencies are employed with the second methodology that provides enhanced power savings. The optimum supply voltage that minimizes clock skew is 44% lower than the nominal supply voltage in a 0.18 ¿m TSMC CMOS technology. Novel multi-threshold voltage level converters and frequency multipliers are employed at the leaves of the clock trees in order to maintain the synchronous system performance. The temperature-fluctuation-induced skew and the power consumption are reduced by up to 80% and 76%, respectively, with the proposed dual supply voltage and dual frequency clock distribution networks as compared to a standard clock tree operating at the nominal supply voltage with a single clock frequency.