Automated Integration of Dual-Edge Clocking for Low-Power Operation in Nanometer Nodes

Abstract

Clocking power, including both clock distribution and registers, has long been one of the primary factors in the total power consumption of many digital systems. One straightforward approach to reduce this power consumption is to apply dual-edge-triggered (DET) clocking, as sequential elements operate at half the clock frequency while maintaining the same throughput as with conventional single-edge-triggered (SET) clocking. However, the DET approach is rarely taken in modern integrated circuits, primarily due to the perceived complexity of integrating such a clocking scheme. In this article, we first identify the most promising conditions for achieving low-power operation with DET clocking and then introduce a fully automated design flow for applying DET to a conventional SET design. The proposed design flow is demonstrated on three benchmark circuits in a 40nm CMOS technology, providing as much as a 50% reduction in clock distribution and register power consumption.

References

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Index Terms

• Hardware

  • Electronic design automation

    • Physical design (EDA)

      • Clock-network synthesis

    • Timing analysis

  • Power and energy

    • Power estimation and optimization

      • Chip-level power issues

      • Circuits power issues

  • Very large scale integration design

    • Full-custom circuits

    • Standard cell libraries

    • VLSI system specification and constraints