FinFET-Based Low-Swing Clocking

Abstract

A low-swing clocking methodology is introduced to achieve low-power operation at 20nm FinFET technology. Low-swing clock trees are used in existing methodologies in order to decrease the dynamic power consumption in a trade-off for 3 issues: (1) the effect of leakage power consumption, which is becoming more dominant when the process scales sub-32nm; (2) the increase in insertion delay, resulting in a high clock skew; and (3) the difficulty in driving the existing DFF sinks with a low-swing clock signal without a timing violation. In this article, a FinFET-based low-swing clocking methodology is introduced to preserve the dynamic power savings of low-swing clocking while minimizing these three negative effects, facilitated through an efficient use of FinFET technology. At scaled performance constraints, the proposed methodology at 20nm FinFET leads to 42% total power savings (clock network+DFF) compared to a FinFET-based full-swing counterpart at the same frequency (3 GHz), thanks to the dynamic power savings of low-swing clocking and 3% power savings compared to a CMOS-based low-swing implementation running at the half frequency (1.5 GHz), thanks to the leakage power savings of FinFET technology.