Novel low leakage and energy efficient dual-pullup/dual-pulldown repeater.

Transistor threshold voltage (V t) scaling causes higher power consumption by increasing the subthreshold leakage and short-circuit currents in CMOS circuits. Leakage currents are significant contributors to the overall power consumption of digital systems-on-chip as threshold voltage, channel length, and gate oxide thickness are reduced with CMOS technology scaling. A new dual-pullup/dual-pulldown (DPU/DPD) repeater is proposed in this paper for higher energy efficiency in low-voltage and low-frequency applications. The standby mode leakage power consumption is reduced by 59.11% with the proposed clock tree as compared to the conventional 3 level H-tree operating with a power supply voltage of 1.0V in a 45 nm CMOS technology. The short-circuit currents are suppressed by selectively employing high-V t transistors in the repeaters. The clock network with the proposed buffer lowers the active mode energy consumption by up to 24.91% as compared to a conventional clock tree under equal silicon area constraint. Post layout results reveal that the statistical spread of clock skew in the DPU/DPD H-tree is also 20.60% lower than the conventional H-tree network. • A novel dual-pullup/dual-pulldown (DPU/DPD) repeater is presented for low leakage and high frequency clock distribution. • The minimum operating voltage of a clock tree is determined for achieving the lowest total energy consumption while satisfying the clock frequency and signal transition time (10% of clock cycle time) requirements at the leaves. • The influences of leakage currents on the total energy consumption of the clock trees designed with three different repeaters (conventional CMOS inverter, previously published SPLIT-IO, and the new DPU/DPD) are benchmarked at various supply voltages and frequencies. • The leakage power reduction provided with the DPU/DPD buffers is evaluated. • The impact of process parameter fluctuations on the clock skew of the novel clock distribution network is also characterized in this paper. [ABSTRACT FROM AUTHOR]