Analysis and Design of Delay Lines for Dynamic Voltage Scaling Applications

Dynamic voltage scaling of bundled-data asynchronous design has the promise to lead to far more energy efficient systems than traditionally clocked alternatives. However, this approach relies on the development of energy-efficient delay lines, whose delay must track that of the combinational datapath over a wide range of voltages. This paper presents a thorough analysis of the design of such delay lines and describes how sizing affects their delay across different voltages. It proposes a design methodology for minimizing energy consumption subject to delay matching constraints. It then applies this methodology to delay lines that consist of four different delay elements in two different technologies, exploring the underlying trade-offs they present.