Qucs-S/QucsStudio/Octave Schematic Synthesis Tools for Device and Circuit Parameter Extraction from Measured Characteristics

A universal technique for the extraction of device parameters or circuit component values from measured performance data is presented. The proposed method can be used by any circuit simulator that implements parameter sweep features and allows user defined tabulated data with independent voltage, or current, sources. A key feature of the reported extraction process is the use of schematic capture simulation icons, with their sweep parameters tabulated as a list of data points, synthesized from CSV measured data. By overlaying simulation output data on top of measured values, then varying user selected parameter/component values and re-simulating repeatable until the two data sets converge, it becomes possible to extract parameter/component values to within a specified error limit. In this paper FOSS circuit simulators Qucs-S/QucsStudio and the numerical analysis package Octave are used to demonstrate the application of the proposed schematic capture synthesis procedure in the investigate of diode inductance at high forward d.c. bias currents and a.c. signal band width.