Steady-state response of nonlinear circuits containing parasitic elements

We propose here a time-domain shooting algorithm for calculating the steady -state responses of nonlinear RF circuits containing parasitic elements tha t is based on both a modified Newton and a secant methods. Bipolar transist ors and MOSFETs in ICs have small parasitic capacitors among their terminal s. We can not neglect them because they will gives large effects to the sho oting algorithm at the high frequency. Since our purpose is to develop a us er friendly simulator, we mainly take into account the relatively large nor mal capacitors such as coupling and/or by-pass capacitors and so on, becaus e the parasitic capacitors are usually smaller and contained in the device models. We have developed a very simple simulator only using the fundamenta l tools of SPICE, which can be applied to relatively large scale ICs, effic iently.