A new time-stepping method for circuit simulation

Abstract

Adaptive time-stepping is crucially important for the efficiency of a circuit simulator. Existing time-stepping methods rely on information at prior time point(s) to select step sizes, which can be problematic when the circuit is undergoing a fast transition. In this work, we propose a new time-stepping method that solves the circuit equations together with the condition for local truncation error (LTE) as one nonlinear system. Circuit solution and step size are obtained simultaneously for the current time point. It allows designers to have direct control of LTE so the errors can be distributed more evenly along non-uniformed time grid. Experiments show the new method generates significantly less time points and is faster for the same accuracy settings. It is also more accurate for the simulation of non-dissipative circuits.