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Circuit Simulation (circuit + simulation)
Selected AbstractsThe effect of parameter mismatches on the output waveform of an LC -VCOINTERNATIONAL JOURNAL OF CIRCUIT THEORY AND APPLICATIONS, Issue 5 2010Antonio Buonomo Abstract The effect of parameter mismatches on the output waveforms of a popular voltage-controlled oscillator is investigated, schematizing the circuit as a system of two mutually coupled oscillators, whose describing equations are derived in a perturbation form. The circuit is studied using the method of two time-scales showing the existence of synchronization phenomena leading in presence of mismatches to a locking frequency, which significantly differs from the natural frequencies of the tanks, and to an oscillation amplitude different from that of the symmetric case. We also show that in-phase and quadrature oscillations at the drain nodes can be generated with a proper parameter setting. Circuit simulations confirm the presence of a synchronized oscillation, which is consistent with the prediction of the presented analysis. Copyright © 2009 John Wiley & Sons, Ltd. [source] Improved analogue fault coverage estimation using probabilistic analysisINTERNATIONAL JOURNAL OF CIRCUIT THEORY AND APPLICATIONS, Issue 5 2010D. K. Papakostas Abstract A method for fault detection probability estimation using statistical multi-parameter circuit simulation is proposed, in order to check circuits for which double or multiple analogue measurements are utilized. Theoretical analysis for the estimation of the fault coverage is given, based on conditional probability calculations. The proposed method can be applied for both test measurement and input stimulus selection. Simulation results from the application of the method on typical analogue circuits,filter and amplifier,are given, showing a sufficient improvement over the fault coverage achieved by single measurements. Copyright © 2009 John Wiley & Sons, Ltd. [source] Implementation of the symmetric doped double-gate MOSFET model in Verilog-A for circuit simulationINTERNATIONAL JOURNAL OF NUMERICAL MODELLING: ELECTRONIC NETWORKS, DEVICES AND FIELDS, Issue 2 2010Joaquín Alvarado Abstract Recently we developed a model for symmetric double-gate MOSFETs (SDDGM) that, for the first time, considers the doping concentration in the Si film in the complete range from 1×1014 to 3×1018,cm,3. The model covers a wide range of technological parameters and includes short channel effects. It was validated for different devices using data from simulations, as well as measured in real devices. In this paper, we present the implementation in Verilog-A code of this model, which allows its introduction in commercial simulators. The Verilog-A implementation was optimized to achieve reduction in computational time, as well as good accuracy. Results are compared with data from 2D simulations, showing a very good agreement in all transistor operation regions. Copyright © 2009 John Wiley & Sons, Ltd. [source] An efficient neural network approach for nanoscale FinFET modelling and circuit simulationINTERNATIONAL JOURNAL OF NUMERICAL MODELLING: ELECTRONIC NETWORKS, DEVICES AND FIELDS, Issue 5 2009M. S. Alam Abstract The present paper demonstrates the suitability of artificial neural network (ANN) for modelling of a FinFET in nano-circuit simulation. The FinFET used in this work is designed using careful engineering of source,drain extension, which simultaneously improves maximum frequency of oscillation ,max because of lower gate to drain capacitance, and intrinsic gain AV0,=,gm/gds, due to lower output conductance gds. The framework for the ANN-based FinFET model is a common source equivalent circuit, where the dependence of intrinsic capacitances, resistances and dc drain current Id on drain,source Vds and gate,source Vgs is derived by a simple two-layered neural network architecture. All extrinsic components of the FinFET model are treated as bias independent. The model was implemented in a circuit simulator and verified by its ability to generate accurate response to excitations not used during training. The model was used to design a low-noise amplifier. At low power (Jds,10,µA/µm) improvement was observed in both third-order-intercept IIP3 (,10,dBm) and intrinsic gain AV0 (,20,dB), compared to a comparable bulk MOSFET with similar effective channel length. This is attributed to higher ratio of first-order to third-order derivative of Id with respect to gate voltage and lower gds in FinFET compared to bulk MOSFET. Copyright © 2009 John Wiley & Sons, Ltd. [source] A global time domain circuit simulation of a microwave rectennaINTERNATIONAL JOURNAL OF NUMERICAL MODELLING: ELECTRONIC NETWORKS, DEVICES AND FIELDS, Issue 1-2 2007Brahim Essakhi Abstract The paper presents a global time domain simulation of a microwave rectenna studied for wireless energy transfer. The novelty of the work is to take into account both distributed electromagnetic parts of the antenna and the rectifier circuit including lumped elements. From a 3D finite element time domain electromagnetic modelling of the structure an equivalent circuit of the antenna is deduced: the input impedance is obtained as a function of frequency over a broad band. Then a rational approximation gives a corresponding PSPICE representation. The electromotive force induced between the ports of the antenna during the microwave illumination is directly computed from the 3D transient scattering problem. The resulting equivalent circuit of the antenna is finally incorporated into the electronic simulator PSPICE, together with the lumped components of the rectenna (ideal diodes and load). Thus a global non-linear time domain analysis of the whole structure becomes available. The results obtained with the methods presented in the paper are compared with those resulting from other techniques. The approach developed in the work could efficiently improve the design stage of rectennas devoted to microwave power transfer. Copyright © 2006 John Wiley & Sons, Ltd. [source] Model order reduction of linear and nonlinear 3D thermal finite-element description of microwave devices for circuit analysisINTERNATIONAL JOURNAL OF RF AND MICROWAVE COMPUTER-AIDED ENGINEERING, Issue 5 2005Raphaël Sommet Abstract Electrothermal models of power devices are necessary for the accurate analysis of their performances. For this reason, this article deals with a methodology to obtain an electrothermal model based on a reduced model of a 3D thermal finite-element (FE) description for its thermal part and on pulsed electrical measurements for its electrical part. The reduced thermal model is based on the Ritz vector approach, which ensures a steady-state solution in every case. An equivalent SPICE subcircuit implementation for circuit simulation is proposed and discussed. An extension of the method to a nonlinear reduced model based on the Kirchoff transformation is also proposed. The complete models have been successfully implemented in circuit simulators for several HBT or PHEMT device structures. Many results concerning devices and circuits are presented, including simulation of both the static and dynamic collector-current collapse in HBTs due to the thermal phenomenon. Moreover, the results in terms of the circuit for an X-band high-power amplifier are also presented. As for the nonlinear approach, results concerning an homogeneous structure is given. © 2005 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2005. [source] Ultra-wideband bandpass filter using simplified left-handed transmission line structureMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 11 2008Wenjia Han Abstract A novel ultra-wideband bandpass filter has been proposed based on a simplified left-handed transmission line (LH-TL) structure. The main design procedure is to define and realize the LH-TL unit cell according to the desired pass band. The filter has been realized in theory, verified by both full-wave electromagnetic simulation and microwave circuit simulation, and confirmed by the measurement with a return loss higher than 12 dB, and the group delay about 0.25 ns over the central band with variation of 0.2 ns. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 2758,2762, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23789 [source] | ||||||||||||||||||||||