Abstract
Recently, the pseudo-transient analysis (PTA) methods have been researched as one of the most effective continuation methods to overcome the non-convergence problem of the Newton-Raphson method for finding the DC operating points of nonlinear circuits. However, the former PTA methods have a time-consuming problem, especially for some large-scale circuits. In this paper, we combine an effective ramping algorithm with two proposed ramping functions and the damped PTA (DPTA) algorithm together to improve the simulation efficiency. It can eliminate the oscillation and time-consuming problems at the same time. Besides, a restart method in the SPICE3 implementation is also proposed, which is effectively to improve convergence when the circuit is stuck in an infinite loop and fails to converge during the simulation. Numerical examples demonstrate the efficiency and convergence improvement of the proposed algorithms.
