The Special Features of Simulation of the Current–Voltage Characteristics of JFETs in the Cryogenic Temperature Range
The compact models of junction field effect transistors (JFETs) used in release-quality versions of SPICE-like programs are focused only on the standard temperatures ranging from –60 to 150°C and are unworkable for an electronic circuit design in the cryogenic temperature range (below –120°C). It this study, the Low-T SPICE model of the JFET for designing electronic circuits in the extended temperature range, including the cryogenic range (from –200 to 110°С), is proposed. The model takes into account the changes in the I–V curves caused by the effect of ultralow temperature: growth of the saturation voltage VD sat, decrease of the pinch-off current Ip and steepness BETA, negative slope LAMBDA of the output I–V curves, increase of the drain–source resistance RD as the result of the freezing effect, etc. For this purpose, the dependences of the specified parameters on temperature are introduced in the model. The procedure for extracting the SPICE parameters of the Low-T SPICE model of the JFET is developed according to the results of the measurements of the standard set of the I–V curves in the cryogenic temperature range. The error of the calculation of the I–V curves is not higher than 10–15% in the temperature range from –200 to 110°C.
The article highlights the status of TCAD and SPICE modeling of CMOS, SOI CMOS, SiGe BiCMOS VLSI components intended for operation under the influence of radiation (neutrons, electrons, protons, y- and X-ray, single particle, pulsed radiation), high (up to +300°C) and low (up to –200°C) temperatures. TCAD and SPICE models of BJTs and MOSFETs, and methods for determining their parameters have been described. Further directions of TCAD and SPICE modeling of IС components have been considered.
The article considers a choice of CAD system and SPICE-models for the circuit simulation of characteristics of the bipolar (BiJFET) analog integrated circuits (IC) at the exposure of the penetrating radiation (PR) and the low temperatures. The authors suggest a modified SPICE-model, which describes the nonmonotonic change of the peak drain current and the slope of the p-n junction FET (JFET) within the temperature range from –200ºС to 30ºС.
This paper presents Low-T SPICE models of sub-micron MOSFETs, designed to calculate electronic circuits in the cryogenic temperature range (down to 4 K). The procedure for extracting the Low-T SPICE model parameters based on the measurement results or TCAD simulation of a standard set of I-V and C-V characteristics in the cryogenic temperature range has been developed.
The temperature range of SPICE models of bipolar and field-effect transistors is extended from the standard commercial level (-60...+150 °C) to harsh conditions level (-200...+300 °C) for low/high temperature ICs design. This is done by including additional equations for temperaturedependent parameters, and by connecting additional elements to the device equivalent circuit to take into account the thermal effects. The universal automated methodology of model parameters extraction from the experimental data measured at low and high temperatures is proposed. The good agreement between simulated and measured device characteristics is achieved. The RMS error is not more than 10–20%.
The JFET compact models used in commercial versions of SPICE-like software tools are oriented only to the standard range of –60 °C…+150 °C and are not suitable for simulation the electronic circuits in the range of cryogenic temperatures (below –120 °C). In the work the JEFT Low-T model, suitable for calculation of circuits in an extended temperature range, including the cryogenic ones (–200…+110 °C) has been developed. The model takes into account the changes in the I-V-characteristics due to the effect of the ultra-low temperature: an increase in the saturation voltage VDsat, a decrease in the pinch-off current Ip and the transconductance BETA, a negative slope LAMBDA on the output I-V-characteristics, an increase in the drain-source resistance RD due to the freeze-out effect, etc. For this purpose, the dependencies of the listed parameters on temperature have been additionally introduced. A procedure has been developed for extracting the SPICE-parameters of the JFET Low-T model from the results of measurements of a standard set of I-V-characteristics in the cryogenic temperature range. The error in simulation of the I-V-characteristics does not exceed 10–15% in the –200…+110 °C temperature range.
The temperature range of SPICE models of bipolar and MOS transistors is extended from –60°C to +150°C (standard commercial level) to –200°C…+300°C for low/high temperature ICs design. This is done by including additional equations for temperature-dependent parameters, and by connecting additional elements to the device equivalent circuit to take into account the thermal effects. The good agreement between simulated and measured device characteritics is achieved. The RMS error is not more than 10–20%.
Generalized error-locating codes are discussed. An algorithm for calculation of the upper bound of the probability of erroneous decoding for known code parameters and the input error probability is given. Based on this algorithm, an algorithm for selection of the code parameters for a specified design and input and output error probabilities is constructed. The lower bound of the probability of erroneous decoding is given. Examples of the dependence of the probability of erroneous decoding on the input error probability are given and the behavior of the obtained curves is explained.
The dynamics of a two-component Davydov-Scott (DS) soliton with a small mismatch of the initial location or velocity of the high-frequency (HF) component was investigated within the framework of the Zakharov-type system of two coupled equations for the HF and low-frequency (LF) fields. In this system, the HF field is described by the linear Schrödinger equation with the potential generated by the LF component varying in time and space. The LF component in this system is described by the Korteweg-de Vries equation with a term of quadratic influence of the HF field on the LF field. The frequency of the DS soliton`s component oscillation was found analytically using the balance equation. The perturbed DS soliton was shown to be stable. The analytical results were confirmed by numerical simulations.
The conference “2021 Systems of signals generating and processing in the field of on board communications” is organized with technical sponsorship of Russian (Moscow) IEEE Circuits and Systems (CAS04) Chapter IEEE Region 8, Russian Section Chapter, MTT/ED and Institute of Radio and Information Systems Association (IRIS), Vienna, Austria. The conference featured invited researchers, educators, managers, and graduate students, whose research activity, case studies or best practices, are shedding light on the theory or practice of engineering, include modern digital transportation systems design and technical operation, radio waves propagation, transmitting, receiving and processing signals in television and radio broadcasting devices, information technologies in transport. The main areas of the conference “Systems of signals generating and processing in the field of on board communications” include modern digital transportation systems design and technical operation, radio waves propagation, transmitting, receiving and processing signals in television and radio broadcasting devices, information technologies in transport. FIELD OF INTEREST: Components, Circuits, Devices and Systems; General Topics for Engineers; Signal Processing and Analysis. Reports presented at the conference are grouped in 6 sections: 1. Antennas and Radio Waves Propagation. 2. Navigation and Mathematical Algorithms of an Object Space Orientation. 3. Radiofrequency Applications. 4. Wire and Optical Communication and Control Systems. 5. Intelligent Transport Systems (ITS): Sub-section 1: Use of digital ITS infrastructure in telematic control systems on urban passenger transport Sub-section 2: Peculiarities of data exchange in cooperative ITS Sub-section 3: Theoretical Aspects of Artificial Intelligence Systems Development for Transportation Engineering Sub-section 4: Test methods of motor vehicles integrated into an intelligent transport environment 6. Digital signal processing in on-board radio systems
Radiation conditions are described for various space regions, radiation-induced effects in spacecraft materials and equipment components are considered and information on theoretical, computational, and experimental methods for studying radiation effects are presented. The peculiarities of radiation effects on nanostructures and some problems related to modeling and radiation testing of such structures are considered.
This volume presents new results in the study and optimization of information transmission models in telecommunication networks using different approaches, mainly based on theiries of queueing systems and queueing networks .
The paper provides a number of proposed draft operational guidelines for technology measurement and includes a number of tentative technology definitions to be used for statistical purposes, principles for identification and classification of potentially growing technology areas, suggestions on the survey strategies and indicators. These are the key components of an internationally harmonized framework for collecting and interpreting technology data that would need to be further developed through a broader consultation process. A summary of definitions of technology already available in OECD manuals and the stocktaking results are provided in the Annex section.