New Electronically Tunable Third Order Filters and Dual Mode Sinusoidal Oscillator Using VDTAs and Grounded Capacitors

This study introduces a third order filter and a third order oscillator configuration. Both the circuits use two voltage difference transconductance amplifiers (VDTAs) and three grounded capacitors. By selecting the input and output terminals properly, current mode and transimpedance mode low-pass and band-pass filters can be obtained without component matching conditions. The natural frequency (ω0) can be tuned electronically. The oscillator circuit provides voltage and current outputs explicitly. The condition of oscillation (CO) and the frequency of oscillation (FO) can be adjusted orthogonally and electronically. The workability of the configurations is judged using TSMC CMOS 0.18 μm technology parameter as well as commercially available LM13700 integrated circuits (ICs). The simulation results show that: for ±0.9V power supply, the power consumption is 1.08 mW for both the configurations, while total harmonic distortions (THDs) are less than 2.06% and 2.17% for the filter and oscillator configurations, respectively

Tunable Lossy and Lossless Grounded Inductors Using Minimum Active and Passive Components

In this contribution, nine new Grounded Inductance Simulators (GISs) using a single Multiple-Output Current Controlled Current Conveyor Transconductance Amplifier (MO-CCCCTA) and one grounded capacitor are proposed. Among them, two are lossless types and seven are lossy types. The use of a single grounded capacitor makes the circuits suitable for fabrication. All the proposed circuits are electronically tunable through the bias currents of MO-CCCCTA. Furthermore, no component matching conditions are needed for realizing them. The designed circuits are verified through PSPICE simulator with ± 0.9 V power supply. The simulation results show that for all the proposed circuits: maximum operating frequencies are about 12 MHz, power dissipation is less than 0.784 mW, Total Harmonic Distortions (THDs) are under 8.09%, and maximum output voltage noise at 1 MHz frequency is 14.094 nV/√Hz. To exhibit the workability of the proposed circuits, they are used to design band-pass, low-pass filter, parallel RLC resonator, and parasitic inductance cancelator

Voltage Differencing Current Conveyor Based Voltage-Mode and Current-Mode Universal Biquad Filters with Electronic Tuning Facility

The objective of this study is to present four new universal biquad filters, two voltage-mode multi-input-single-output (MISO), and two current-mode single-input-multi-output (SIMO). The filters employ one voltage differencing current conveyor (VDCC) as an active element and two capacitors along with two resistors as passive elements. All the five filter responses, i.e., high-pass, low-pass, band-pass, band-stop, and all-pass responses, are obtained from the same circuit topology. Moreover, the pole frequency and quality factor are independently tunable. Additionally, they do not require any double/inverted input signals for response realization. Furthermore, they enjoy low active and passive sensitivities. Various regular analyses support the design ideas. The functionality of the presented filters are tested by PSPICE simulations using TSMC 0.18 µm technology parameters with ± 0.9 V supply voltage. The circuits are also justified experimentally by creating the VDCC block using commercially available OPA860 ICs. The experimental and simulation results agree well with the theoretically predicted results

[Transitional strength under plasma] Precise estimations of astrophysically relevant electromagnetic transitions of Ar7+^{7+}, Kr7+^{7+}, Xe7+^{7+}, and Rn7+^{7+} under plasma atmosphere

The growing interest in atomic structures of moderately-stripped alkali-like ions in diagnostic study and modeling of astrophysical and laboratory plasma makes an accurate many-body study of atomic properties inevitable. This work presents transition line parameters in the absence or presence of plasma atmosphere for astrophysically important candidates, Ar$^{7+}$, Kr$^{7+}$, Xe$^{7+}$, and Rn$^{7+}$. We employ relativistic coupled-cluster (RCC) theory, a well-known correlation exhaustive method. In the case of a plasma environment, we use Debye Model. Our calculations agree with experiments available in the literature for ionization potentials, transition strengths of allowed and forbidden selections, and lifetimes of several low-lying states. The unit ratios of length and velocity forms of transition matrix elements are the critical estimation of the accuracy of the transition data presented here, especially for a few presented first time in the literature. We do compare our findings with the available recent theoretical results. Our reported data can be helpful to the astronomer in estimating the density of the plasma environment around the astronomical objects or in the discovery of observational spectra corrected by that environment. The present results should be advantageous in the modeling and diagnostics laboratory plasma, whereas the calculated ionisation potential depression parameters reveal important characteristics of atomic structure

A Simple Analytical Model of a GaN MODFET to Study its DC and RF Performance

395-400This work presents a theoretical study of a GaN MODFET considering accurate velocity field relation of GaN for a wide range of electric field. The analytical expression of different DC parameters such as drain current, mutual conductance and drain conductance of the device has been derived and their variation over different field regions has been investigated. This work has also been extended to study the RF parameters like cut-off frequency and maximum operating frequency of the device. The threshold voltage of the device is also derived and studied in terms of the thickness of the doped AlGaN layer and mole fraction of AlGaN. The mathematical model presented here is calibrated with the experimentally available results reported earlier and a good agreement has been observed

Lossy & Lossless Capacitance Multipliers: A Series of Realization Using VDTAs & Single Grounded Capacitor

The article presents new realizations of capacitance multiplier circuits, employing two voltage differencing transconductance amplifiers (VDTAs) and one capacitor without any passive resistors. The equivalent capacitance value of the proposed capacitance simulators can be achieved electronically by regulating the DC bias currents of VDTAs. All the proposed realizations do not require any critical component matching conditions. The lossless floating negative capacitor multiplier (NCM) circuit is studied in detail. The capacitive cancellation scheme and a quadrature sinusoidal oscillator circuit are included to demonstrate the effectiveness of the circuit. The effect of the VDTA non-idealities and parasitic on the realized circuits is analysed. SPICE simulation results using TSMC 0.18 μm CMOS technology parameters are presented to reflect the workability of the proposed NCM

A Simple Analytical Model of a GaN MODFET to Study its DC and RF Performance

This work presents a theoretical study of a GaN MODFET considering accurate velocity field relation of GaN for a wide range of electric field. The analytical expression of different DC parameters such as drain current, mutual conductance and drain conductance of the device has been derived and their variation over different field regions has been investigated. This work has also been extended to study the RF parameters like cut-off frequency and maximum operating frequency of the device. The threshold voltage of the device is also derived and studied in terms of the thickness of the doped AlGaN layer and mole fraction of AlGaN. The mathematical model presented here is calibrated with the experimentally available results reported earlier and a good agreement has been observed

Transitional Strength under Plasma: Precise Estimations of Astrophysically Relevant Electromagnetic Transitions of Ar⁷⁺, Kr⁷⁺, Xe⁷⁺, and Rn⁷⁺ under Plasma Atmosphere

The growing interest in atomic structures of moderately stripped alkali-like ions in the diagnostic study and modeling of astrophysical and laboratory plasma makes an accurate many-body study of atomic properties inevitable. This work presents transition line parameters in the absence or presence of plasma atmosphere for astrophysically important candidates Ar7+, Kr7+, Xe7+, and Rn7+. We employ relativistic coupled-cluster (RCC) theory, a well-known correlation exhaustive method. In the case of a plasma environment, we use the Debye Model. Our calculations agree with experiments available in the literature for ionization potentials, transition strengths of allowed and forbidden selections, and lifetimes of several low-lying states. The unit ratios of length and velocity forms of transition matrix elements are the critical estimation of the accuracy of the transition data presented here, especially for a few presented for the first time in the literature. We do compare our findings with the available recent theoretical results. Our reported data can be helpful to the astronomer in estimating the density of the plasma environment around the astronomical objects or in the discovery of observational spectra corrected by that environment. The present results should be advantageous in the modeling and diagnostics laboratory plasma, whereas the calculated ionization potential depression parameters reveal important characteristics of atomic structure