A unified approach to compact device modelling with the open source packages Qucs/ADMS and MAPP/Octave

Qucs-0.0.18: Structure and basic modelling features; Qucs-0.0.19: Introducing the next generation Qucs simulation and modelling tools; Qucs circuit simulation and device modelling: Simulation, subcircuits, post-simulation data processing, algebraic equation-defined components and embedded design routines. Compact device modelling: 1. Equation-Defined Device models (EDD), Radio Frequency and Equation-Defined Models (FEDD); 2. Analogue Device Model Synthesis (ADMS) of Verilog-A behavioural and lower level device and circuit models, Qucs ADMS/Verilog-A “turn-key” tools; 3. Expanded compact device modelling capabilities with the Berkeley Model and Algorithm Prototyping Platform (MAPP); 4. A unified GPL compact device modelling and simulation platform

Qucs Frequency Domain Non-Linear Compact Modelling and Simulation of IC Spiral Inductors on Silicon

SPICE AC circuit simulation is fundamentally a small signal network analysis of linear or non-linear circuits operating at specified DC bias conditions, where the circuit component values are assumed not to be functions of AC input signal frequency. In the case of RF circuit simulation this assumption can give rise to significant modelling errors. With the recent improvementsinGeneralPublicLicense(GPL)circuitsimulators thissituationischanging,particularlythroughtheintroductionof Frequency Dependent Equation-Defined Device (FEDD) models, non-linear current/voltage static and dynamic Equation-Defined Device (EDD) models and user controlled swept signal frequency simulation employing Harmonic Balance steady state analysis. The main purpose of this paper is to introduce a number of novel modelling and circuit simulation techniques that allow, and enhance, the construction of compact device models with embedded behavioural components whose non-linear properties are functions of AC input signal frequency. To demonstrate these new modelling techniques a compact model for a 10 GHz band width spiral inductor integrated on silicon is introduced, its compact model presented, and finally its simulation performance compared with published measured device data

Equation-defined template and synthesis driven compact modelling of semiconductor devices

The rapid expansion in emerging semiconductor devices has led to the need for improved compact modelling and circuit simulation tools. In order to achieve wide spread acceptance of any new modelling tool it must be simple to use, generate device models that produce accurate simulation data, simulate at practical speeds, meet international hardware description language standards and be freely available to the compact modelling community. This presentation reports on current research that links Equation-Defined Device modelling with Verilog-A modules, driven by code templates and synthesis, which in turn result in an improved interactive modelling technique that can be employed to construct compact models that have a similar performance to compiled C++ code models. Throughout the talk a series of compact device models will be introduced to demonstrate the fundamentals and application of the new approach to compact device modelling

Verilog-A compact modelling of SiC devices with Qucs-S, QucsStudio and MAPP/Octave FOSS tools

Qucs-S is a spin-off of the Qucs cross-platform circuit simulator. "S" letter indicates SPICE. The purpose of the Qucs-S subproject is to use free SPICE circuit simulation kernels with the Qucs GUI. It merges the power of SPICE and the simplicity of the Qucs GUI. Qucs intentionally uses its own SPICE incompatible simulation kernel Qucsator. It has advanced RF and AC domain simulation features, but most of the existing industrial SPICE models are incompatible with it. Qucs-S is not a simulator by itself, but it requires to use a simulation backend with it. The schematic document format of Qucs and Qucs-S are fully compatible. Qucs-S allows to use the following simulation kernels with it: Ngspice is recommended to use. Ngspice is powerful mixed-level/mixed-signal circuit simulator. The most of industrial SPICE models are compatible with Ngspice. It has an excellent performance for time-domain simulation of switching circuits and powerful postprocessor. XYCE is a new SPICE-compatible circuit simulator written by Sandia from the scratch. It supports basic SPICE simulation types and has an advanced RF simulation features such as Harmonic balance simulation. SpiceOpus is developed by the Faculty of Electrical Engineering of the Ljubljana University. It based on the SPICE-3f5 code Qucsator as backward compatible

Qucs modelling and simulation of analog/RF devices and circuits (Chapter 6)

Trends in compact device modeling and analog circuit simulation point towards a growing interest among the modeling community in the standardization of Verilog-A as an equation based modeling language for compact semiconductor device model and circuit macromodel development. . This chapter introduces the principles of compact device modeling with equation-defined devices and VerilogA models. For completeness circuit macromodel principles and construction are also included. It also describes the use of the different types of equation based models in analog and RF circuit simulation. Throughout the text the properties of a range of analog and RF circuits with different levels of complexity are introduced and their performance investigated with the “Quite universal circuit simulator” (Qucs) and its related software package QucsStudio. All the device and circuit modeling techniques introduced in this chapter form part of the standard features implemented in Qucs and QucsStudio

Frequency domain non-linear compact modelling and simulation of IC spiral inductors on silicon

SPICE AC circuit simulation is fundamentally a small signal network analysis of a linear or non-linear circuit operating at specified DC bias conditions, where the electrical network component values are assumed not to be functions of AC input signal frequency. In the case of RF circuit simulation this assumption can give rise to significant modelling errors.With the recent improvements in General Public License (GPL) circuit simulators this situation is changing, particularly through the introduction of Frequency Dependent Equation-Defined Device (FEDD) models, non-linear current/voltage static and dynamic Equation-DefinedDevice(EDD)modelsandusercontrolledswept signal frequency simulation employing Harmonic Balance steady state analysis. The main purpose of this paper is to introduce a number of novel modelling and circuit simulation techniques that allow, and enhance, the construction of compact device models with embedded behavioural components whose non-linear properties are functions of AC input signal frequency. To demonstrate these new modelling techniques a compact model for a 10 GHz band width spiral inductor integrated on silicon is introduced, its compact model presented, and finally its simulation performance compared with published measured device data

An outline of Qucs-S compact device modelling: History and capabilities: Part 2 XSPICE Code Models; basic properties to model synthesis, and beyond

Qucs-S is a spin-off of the Qucs cross-platform circuit simulator. "S" letter indicates SPICE. The purpose of the Qucs-S subproject is to use free SPICE circuit simulation kernels with the Qucs GUI. It merges the power of SPICE and the simplicity of the Qucs GUI. Qucs intentionally uses its own SPICE incompatible simulation kernel Qucsator. It has advanced RF and AC domain simulation features, but most of the existing industrial SPICE models are incompatible with it. Qucs-S is not a simulator by itself, but it requires to use a simulation backend with it. The schematic document format of Qucs and Qucs-S are fully compatible. Qucs-S allows to use the following simulation kernels with it: Ngspice is recommended to use. Ngspice is powerful mixed-level/mixed-signal circuit simulator. The most of industrial SPICE models are compatible with Ngspice. It has an excellent performance for time-domain simulation of switching circuits and powerful postprocessor. XYCE is a new SPICE-compatible circuit simulator written by Sandia from the scratch. It supports basic SPICE simulation types and has an advanced RF simulation features such as Harmonic balance simulation. SpiceOpus is developed by the Faculty of Electrical Engineering of the Ljubljana University. It based on the SPICE-3f5 code Qucsator as backward compatible

Qucs equation-defined and Verilog-A RF device models for harmonic balance circuit simulation

This paper is concerned with the development and evaluation of a number of modelling techniques which improve Qucs Harmonic Balance simulation performance of RF compact device models. Although Qucs supports conventional SPICE semiconductor device models, whose static current/voltage and dynamic charge characteristics exhibit second and higher order derivatives may not be continuous, there is no guarantee that these will function without Harmonic Balance simulation convergence problems. The same comment also applies to a number of legacy compact semiconductor device models. The modelling of semiconductor devices centred on non-linear Equation-Defined Devices and blocks of Verilog-A code, combined with linear components, is introduced. These form a class of compact macromodel that has improved Harmonic Balance simulation performance. To illustrate the presented modelling techniques RF diode and bipolar junction transistor macromodels are described and their Harmonic Balance performance simulated with Qucs and Xyce

Qucs: a GPL software package for circuit simulation, compact device modeling and circuit macromodeling from DC to RF and beyond

Qucs is an open source circuit simulator with extensive device and circuit modeling capabilities. It is one of the GPL simulators supporting VerilogA compact model standardization. Versions are available for most of the popular computer operating systems. The package is equipped with a range of device and modeling features which allow fast prototyping of experimental compact device and circuit macromodels. These include, traditional subcircuits, equation defined devices and Verilog-A compact models generated using the ADMS compiler. Recent improvements to the Qucs/ADMS interface now allow a well defined procedure for VerilogA model construction. This paper outlines the structure and simulation capabilities of the Qucs simulator. To illustrate the performance of this emerging GPL simulator a number of examples taken from DC to RF are described. The paper also presents a comparative study of photodiode model development using the different Qucs modelling techniques, and finally introduces a new compact macromodel, with equation monitoring capabilities, for the EKV 2.6 MOSFET model

Qucs Equation-Defined and Verilog-A Higher Order Behavioral Device Models for Harmonic Balance Circuit Simulation

This paper is concerned with the development and evaluation of a number of modeling techniques which improve Qucs Harmonic Balance simulation performance of RF compact device models. Although Qucs supports conventional SPICE semiconductor device models, whose static current/voltage and dynamic charge characteristics exhibit second and higher order derivatives may not be continuous, there is no guarantee that these will function without Harmonic Balance simulation convergence problems. The same comment also applies to a number of legacy compact semiconductor device models. The modeling of semiconductor devices centered on non-linear Equation-Defined Devices and blocks of Verilog-A code, combined with linear components, is introduced. These form a class of compact macromodel that has improved Harmonic Balance simulation performance. To illustrate the presented modeling techniques RF diode, BJT and MESFET macromodels are described and their Harmonic Balance performance simulated with Qucs and Xyce