Improved clock-gating control scheme for transparent pipeline

This paper presents a stage-level clock-gating scheme for clock power improvement. The proposed technique efficiently implements the concept of transparent pipeline which improves clocking power by dynamically making pipeline registers transparent. We developed new control scheme for transparent pipeline which can be applied to any number of pipeline stages. A low-overhead flip-flop with transparent mode is also proposed to reduce implementation overhead. The proposed clock-gating control logic is extended to pipeline collapsing which allows energy/performance trade-off through dynamic frequency scaling. Simulation results on IBM 90 nm technology show that the proposed approach has less overhead (~25%) than the previous transparent pipeline scheme and improves up to 40% of clocking power in 64-bit 7-stage pipeline over traditional stage-level clock-gating technique.