Adaptation of Classical Design Flow for Energy-Driven System-to-Circuit Design

This chapter starts by sketching the classical (digital) top—down design flow and its advantages; separate layers of abstraction allow to gradually refine a design. This strategy increases the design efficiency and allows the designer to tackle the design of large systems. Unfortunately, it is exactly this strict separation between the different abstraction layers which forms a problem in present-day energy-limited designs. The design of such energy-optimized systems requires a careful balancing of the system's performance and its power consumption. This is only possible by considering high-level system aspects in parallel with lower level architectural and circuit implications. A new kind of energy-driven crosslayer design strategy is needed. The second part of this chapter will propose several adaptations of the classical design flow. Yet, the basic concept of this design flow, the different design abstraction layers, is not abandoned, since it is indispensable in the design of large complex systems.

The insertion of an early design space exploration (DSE) step in the design process and the introduction of crosslayer design techniques are two of the adaptations proposed in this chapter. Additionally, the role of flexibility in the system under design will be discussed. By introducing flexibility knobs at design time, the system can dynamically adapt to changing requirements at run time, which results in additional energy savings. The presented design strategy should, hence, optimally balance the system's power consumption, performance, and flexibility to minimize the overall energy consumption at run time.