Performance analysis and optimisation of NCL self-timed rings

摘要

A self-timed ring using NULL convention logic (NCL) is presented. An analytical method to evaluate the speed of NCL rings has been developed. The analytical predictions are verified by a Synopsys simulation and excellent agreement between the theoretical predictions and simulation results is obtained. Some important principles for ring optimisation are obtained. The analysis leads to the speed optimisation of a 24-bit NCL divider.