The aim of this paper is to prove that, through a canonic approach, sinusoidal oscillators based on second-generation voltage conveyor (VCII) can be implemented. The investigation demonstrates the feasibility of the design results in a pair of new canonic oscillators based on negative type VCII (VCII−). Interestingly, the same analysis shows that no canonic oscillator configuration can be achieved using positive type VCII (VCII+), since a single VCII+ does not present the correct port conditions to implement such a device. From this analysis, it comes about that, for 5-node networks, the two presented oscillator configurations are the only possible ones and make use of two resistors, two capacitors and a single VCII−. Notably, the produced sinusoidal output signal is easily available through the low output impedance Z port of VCII, removing the need for additional voltage buffer for practical use, which is one of the main limitations of the current mode (CM) approach. The presented theory is substantiated by both LTSpice simulations and measurement results using the commercially available AD844 from Analog Devices, the latter being in a close agreement with the theory. Moreover, low values of THD are given for a wide frequency range.

A New VCII Application: Sinusoidal Oscillators

In this study, two circuit topologies for simulating tunable lossy floating inductors are proposed. In each design, the simulators make use of a single voltage differencing transconductance amplifi...

Single VDTA-Based Tunable Floating Lossy Inductance Simulation Circuits

In this paper, four floating/grounded series and parallel immittance simulator topologies are proposed, utilizing voltage differencing transconductance amplifiers (VDTAs) as useful active devices. Each of the proposed topologies requires only two grounded passive components. The floating series and parallel simulated immittance circuits proposed here require just two VDTAs, whilst the grounded ones require only one. The proposed topologies can simulate R-L, R-C, and L-C immittances in series and parallel. All of the simulated equivalent elements for the realized immittances are orthogonal adjustable. Furthermore, there are no critical element equality criteria required for the desired immittance function realization. The behavior of the proposed VDTA-based immittance simulators is exemplified in LC ladder filter and sinusoidal oscillator applications. To illustrate the simulator's performance, PSPICE simulation and experimental test results are used. 

Floating/grounded series/parallel R-L, R-C and L-C immittance simulators employing VDTAs and only two grounded passive elements

This article relates to the realization of voltage-mode and/or current-mode multifunction biquadratic filter and quadrature oscillator circuits each using one voltage differencing gain amplifier (VDGA), two resistors and two grounded capacitors.  The proposed dual-mode filter having one output and three inputs can provide the three standard biquadratic transfer functions with both voltage and current output filter responses simultaneously.  It also has the independent tuning of the angular resonance frequency and the quality factor .  With a slight modification of the proposed filter, a new dual-mode quadrature sinusoidal oscillator can be obtained.  The proposed quadrature oscillator provides orthogonal resistive/electronic control of both oscillation condition and oscillation frequency.  Non-ideal and parasitic conditions are also examined and their effects on the circuit performance are discussed.  In order to confirm the theory, several computer simulation results with PSPICE program are given .

/pdf/single-vdga-based-dual-mode-multifunction-biquadratic-filter-4k5l0o79pt.pdf

Single VDGA-Based Dual-Mode Multifunction Biquadratic Filter and Quadrature Sinusoidal Oscillator

The study presents two new realisations of bipolar two-quadrant implicit RMS-to-DC converter and four-quadrant multiplier/divider employing two VDTAs (voltage differential transconductance amplifier) and grounded passive elements. The converters provide the operating frequency of up to 10 MHz with increased precision in the processing of input currents signals, when compared to known realisations. Errors related to the signal processing and errors bound were investigated and presented in this study. The results obtained from the simulation tests in HSPICE and the experimentally realised models of the converters showed a good match with the theoretical anticipation. The maximum power consumption of the converters is 2.82 mW, at ±1.2 V supply voltages.

New current-mode RMS-to-DC converters and four-quadrant multiplier/divider based on VDTA

A new circuit for a simple resistorless quadrature oscillator is proposed in this work. The circuit consists of a single voltage dependant transconductance amplifier block and two grounded capacitors which ease IC fabrication. The workability of the circuit has been verified using 180 nm CMOS based TSMC Technology. Moreover, an experiment is performed using a prototype assembled using a commercially available operational transconductance amplifier IC LM3080.

Single VDTA based resistorless quadrature oscillator

This paper presents a current mode quadrature oscillator using current differencing transconductance amplifier (CDTA). The proposed circuit uses a single CDTA, one resistor, and two capacitors. The designed circuit enjoys the advantages of independent control of condition of oscillation (CO) and frequency of oscillation (FO). The performance of the proposed circuit is examined using PSPICE with model parameters of TSMC 0.18 µm.

Current Differencing Transconductance Amplifier (CDTA) Based Current Mode Quadrature Oscillator

The following research paper gives a different type of voltage mode multifunction filter which is of first order, which consist of only one OTRA block that is operational transresistance amplifier and few of the passive components. This structure can be used for employing different types of filter functions of 1st order. The proposed device is simulated with the parameters of 0.5µm CMOS which is defined by MOSIS (AGILENT). The results are verified using simulation software PSPICE.

Multi Input Single Output using Operational Transresistance Amplifier as First Order Filter

This research paper introduces a fully controllable negative inductor and two R-L Immittance simulator using Differential Voltage Current Conveyor (DVCC) and some passive components. One of the immittance simulators is a parallel RL and other is series R and L. All the three simulators use two resistors and one capacitor. Workability of all the simulators are tested by 0.5μm CMOS Technology.

http://ieeexplore.ieee.org/iel7/7505241/7522405/07522462.pdf

Khushi Banerjee

Papers

Single VDTA based resistorless quadrature oscillator

Current Differencing Transconductance Amplifier (CDTA) Based Current Mode Quadrature Oscillator

Multi Input Single Output using Operational Transresistance Amplifier as First Order Filter

Negative inductance and immittance simulators employing differential voltage current conveyor