Three port gyrator circuits using transconductance amplifiers or generalized conveyors

This chapter discusses prominent contributions made over the last five decades on the evolution of gyrators, synthetic inductances and other related immittances using current conveyors (CCs) and their numerous variants developed over the years. The various circuits using the most basic forms of CCs, namely the first-generation CCs (CCI) and the second-generation CCs (CCII) have been elaborated first. This is then followed by the circuits employing an electronically controllable version of CCII called controlled second-generation current conveyor. Finally, numerous recent circuits based on different variants of CCs such as dual-output CCIIs, differential voltage CCs, third-generation CCs, differential difference CCs, inverting CCII, dual-X CCII and fully differential CCII and numerous combinations thereof have been dealt with. A number of applications of the various synthetic impedances have been elaborated.

This paper presents a comparison and performance analysis of CMOS-based VDCC (Voltage Differencing Current Conveyor) circuits and differential amplifier FGMOS-based circuits. Differential amplifiers at the input stage of the VDCC circuit are designed using FGMOS instead of CMOS. Designing the differential amplifiers in the input stages of the VDCC circuit using FGMOS instead of CMOS amplifies the input signal of the circuit, providing a significant increase in linearity and voltage following properties. At the same time by using FGMOS transistors, the input stage of the circuit, which provides arithmetic calculations, is simplified. A three-input single output (TISO) type band-pass filter application is given to show the versatility of the VDCC circuit topology. The THD value of the CMOS-based VDCC filter circuit is found to be 15.99%. The THD value of the proposed differential amplifiers FGMOS-based VDCC filter circuit is found to be 1.03%. Theoretical analysis results confirm the simulation results. The presented CMOS and FGMOS-based band-pass filters are simulated using TSMC CMOS 0.18 μm technology with VDD, a power supply voltage equal to 0.9 V. The proposed circuit topology will be an essential reference in the literature for researchers to design new linearly tunable filters.

This paper presents a novel One-shot pulse Generator Circuit, which is composed of only one differential voltage current conveyor (DVCC) as the active element. The application circuits utilizing the DVCC are introduced and implemented. Only one DVCC and two resistors and one capacitor are required to construct every circuit. Each circuit is able to provide a pulse-shaped response having changeable width via a positive-edge triggered signal. The first one is a general one-shot pulse generating circuit. The second design can reduce the recovery time after applying triggered signals. Is-Spice is the simulation software to simulate every model. To fabricate the models commercially available ICs (AD844AN) and passive elements are required. Program and experimental outputs satisfy theoretical results.

The design of transconductance-mode multifunction biquad filter containing three input voltage nodes and single-output current node is proposed. Its circuit principle is emphasized on employing Voltage Differencing Current Conveyor (VDCC) to be an active building block. The proposed filter description uses three VDCCs co-working with two grounded capacitors and three grounded resistors. The synthesis of the proposed multifunction filter is based on avoidance of using multiple-output active elements to achieve commercially available integrated circuits for practical implementation. Additionally, without multiple-output active element, it can alleviate current tracking error from the current mirrors used in output ports. It also decreases the amounts of the transistors inside the active elements. The proposed multifunction filter offers all 5 filter functions, which are non-inverting Low-Pass (LP), non-inverting High-Pass (HP), non-inverting Band-Pass (BP), non-inverting Band-Reject (BR) and also non-inverting All-Pass (AP) functions from same circuit topology under different circuit condition for input signals. Furthermore, the natural frequency for all filtering responses is independently achieved from the bandwidth or the quality factor of the proposed filter. For cascade-able connectivity, the output current port indeed provides a high impedance. In addition, the magnitude of the output current for all filtering functions can be resistively adjusted. The consideration for non-ideal case of the presented multifunction filter is also analyzed. The simulation and experimental results of the presented transconductance multifunction biquad filter based on VDCC practically implemented by the commercially available ICs, LM13700 and AD844 can validate the theoretical anticipation.

In this article a new electronically controllable grounded frequency-dependent negative resistance (FDNR) simulation circuit is proposed. The presented circuit employs two voltage differencing current conveyors (VDCCs), two grounded capacitances and one grounded resistance. The proposed configuration simulates a grounded FDNR without any requirement of component matching and enjoys the electronic control through transconductances of VDCCs. The presented circuit exhibit excellent non-ideal behavior and low values of sensitivity figures. The high frequency limitation of realized configuration has been evaluated under the influence of parasitic impedances. The workability of the proposed FDNR has been confirmed by SPICE simulations using CMOS VDCC.

MOS-C realizations of the Kerwin–Huelsman–Newcomb (KHN) circuit using the commercially available Voltage Operational Amplifier (VOA) and the Current Feedback Operational Amplifier (CFOA) are reviewed in this paper. Additional MOS-C KHN realizations using the Operational Transresistance Amplifier (OTRA) and the Differential Current Voltage Conveyor (DCVC) are also included. MOS-C realizations of the KHN circuit using CMOS operational amplifier, CMOS current feedback operational amplifier and CMOS operational transresistance amplifier are also given.Spice simulation results using 0.18 CMOS technology model from MOSIS are included together with detailed comparison tables to demonstrate the differences between MOS-C KHN circuits using both of the commercially available active building blocks and CMOS integrated building blocks. A comparison with the Gm-C KHN circuit is also included.

The design procedure of general immittance inverters is described. Three types of such an inverter were derived using general current or general voltage conveyors. Realizations of grounded inductors employing DVCC (differential-voltage current conveyor) elements and their simulated frequency characteristics are shown.

Article On the Realization of Second Order Current Mode Active Filters Using Single Differential Voltage Current Conveyor (DVCC) was published on May 1, 2003 in the journal Frequenz (volume 57, issue 5-6).

Design and implementation of monostable multivibrators employing differential voltage current conveyors

Synthesis of active inductors using SFG stamps

The pathological mirror and nullor representation of the two‐output current conveyor family is given. New pathological mirror and nullor representations of the two‐output current conveyor family are given and compared with the corresponding nullator norator resistors' realizations. Simplified representations of the two‐output current conveyors based on using two single‐output current conveyors are given. Two examples are given, the first example demonstrates the importance of the pathological representation in the generation of a family of 16 oscillators from a two‐output current conveyor‐based current mode oscillator. A second example of a current mode low‐pass filter using two single‐output inverting current conveyors is considered. Its simplified modeling using a single balanced output inverting current conveyor is compared with the original current mode filter and the simulation results are given. Copyright © 2010 John Wiley & Sons, Ltd.

A new versatile voltage-mode multifunction biquadratic filter with three inputs and four outputs is proposed. The proposed configuration employs two differential voltage current conveyors (DVCCs) as active elements together with two grounded capacitors and two resistors as passive elements. The circuit can act as a multifunction voltage-mode filter with two inputs and four outputs and can perform simultaneous realization of voltage-mode bandreject, highpass, bandpass and lowpass filter signals from the four output terminals, respectively, without any component choice conditions. On the other hand, it also can act as a universal voltage-mode filter with three inputs and a single output and can realize five generic voltage-mode filter signals from the same configuration without any component matching conditions. HSPICE and MATLAB simulations results are provided to demonstrate the theoretical analysis.

To further extend the existing knowledge on voltage-mode universal biquadratic filter, in this paper, a new biquadratic filter circuit with single input and multiple outputs is proposed, employing three differential voltage current conveyors (DVCCs), three resistors, and two grounded capacitors. The proposed circuit realizes all the standard filter functions, that is, high-pass, band-pass, low-pass, notch, and all-pass filters simultaneously. The circuit enjoys the feature of high-input impedance, orthogonal control of resonance angular frequency (<svg style="vertical-align:-3.22281pt;width:16.862499px;" id="M1" height="11.0375" version="1.1" viewBox="0 0 16.862499 11.0375" width="16.862499" xmlns="http://www.w3.org/2000/svg"> <g transform="matrix(1.25,0,0,-1.25,0,11.0375)"> <g transform="translate(72,-63.17)"> <text transform="matrix(1,0,0,-1,-71.95,66.44)"> <tspan style="font-size: 12.50px; " x="0" y="0">𝜔</tspan> </text> <text transform="matrix(1,0,0,-1,-63.44,63.31)"> <tspan style="font-size: 8.75px; " x="0" y="0">o</tspan> </text> </g> </g> </svg>), and quality factor (<i >Q</i>) via grounded resistor and the use of grounded capacitors which is ideal for IC implementation.

The paper presents a new current mode biquadratic filter with one input and three outputs using differential voltage current conveyor (DVCC) and four passive components. The proposed circuit can simultaneously realize low-pass, band-pass, and high-pass filter functions without changing the circuit topology and passive elements. The circuit exhibits a good frequency performance and low-sensitivity figures. PSPICE simulation using 0.5 μm CMOS parameters are given to validate the proposed circuit. The circuit provides a simple yet novel solution to the current-mode filtering after appropriate incorporation of current sensing elements in form of current buffers.

The paper presents a new quadrature oscillator of third order which can provide four quadrature current outputs and two quadrature voltage outputs. The new circuit employs three differential voltage current conveyors and six passive components, most of which are in grounded form. Circuit operation at high frequencies is verified along with nonideality and parasitic study. The circuit enhancement for generation of four phase clock waveforms is also given. The proposed circuit is a novel addition to the oscillator family.