Scaling Energy Per Operation via an Asynchronous Pipeline

Statistical analysis of computations per unit energy in processors over the last 30 years is given that illustrates a sharp reduction in the rate of energy efficiency improvements over the last several years resulting in the formation of an asymptotic “wall” with our dataset; we use the measure of giga multiply accumulates per Joule. We have developed an energy model which takes into account the realities of scaling, specifically for asynchronous systems. Studies of an energy efficient asynchronous pipeline show fabricated results of 17 Giga Operations per Joule in 0.6 μm at subthreshold when fully pipelined, and simulations at a more modern 65 nm process show a further order of magnitude improvement on that.