A SIMULATION TOOL FOR THE ANALYSIS AND VERIFICATION OF THE STEADY-STATE OF CIRCUIT DESIGNS

Analogue and microwave design requires accurate and reliable simulatio n tools and methods to meet the design specifications. System properti es are often measured in the steady state. Well-suited algorithms for calculating the steady state can be classified into shooting methods, finite difference methods and the harmonic balance (HB) technique. Har monic balance is a frequency domain method which approaches the proble m of finding the steady state by a trigonometric polynomial. Depending on the size of the circuit and the number of Fourier coefficients of the polynomial, the resulting system of non-linear equations can becom e very large. These non-linear equations are solved by using Newton's method. The sparse linear system arising from Newton's method can be s olved by direct, stationary or non-stationary iterative solvers. Itera tive methods are normally easy to parallelize or vectorize. In this pa per a tool for the simulation of the steady state of electronic circui ts is presented. The steady state is calculated using the harmonic bal ance technique. Non-linear equations are solved by Newton's method and linear equations by preconditioned non-stationary iterative solvers ( CGS, Bi-CGSTAB, BiCGSTAB(2), TFQMR). The run time is reduced dramatica lly, by up to an order of magnitude.