ABSTRACTS OF ARTICLES OF THE JOURNAL "INFORMATION TECHNOLOGIES".
No. 10. Vol. 25. 2019

DOI: 10.17587/it.25.584-590

M. M. Gourary, Senior Research Associate, gourary@ippm.ru, Institute for Design Problems in Microelectronics RAS

Effective Algorithm for Ring Oscillator Simulation Using the Harmonic Balance Method

Ring oscillators are a well-studied class of circuits due to their wide application. However, modeling their characteristics in the frequency domain encounters difficulties associated with the poor convergence of the numerical continuation process for the harmonic balance equations of such schemes. The paper presents an analysis of the features of the system of harmonic balance equations for ring oscillators, and it is shown that the existence of several solutions of this system is the source of difficulties. It is also shown that the problem persists within the framework of the approach proposed in the literature based on the simulation of an equivalent single-stage circuit representing ring oscillators with identical cascades. To solve the problem, the inclusion of a preliminary stage in the simulation that takes into account only one harmonic of the solution. The new approach to ring oscillator simulation not only essentially improves the reliability of convergence, but also reduces computational efforts of the steady-state simulation. Numerical experiments presented in the paper confirm the obtained theoretical conclusions.
Keywords: design automation, circuit simulation, ring oscillator, harmonic balance, parameter continuation, iterative methods

To the contents