R. Nandi

Inductor simulation using a current conveyor

Two schemes of simulating grounded inductors using a second generation current conveyor are reported. Both schemes provide simulated inductors that are relatively frequency independent, with suitable design, at moderately high-Q values.

Wien bridge oscillators using current conveyors

Realization of oscillators with single resistor control based on the circuit techniques of the second generation current conveyors (CC II) utilizing the separability of the Wien RC one-ports that are generalized through appropriate insertion of two more resistors is considered. The relative frequency stability is shown to improve over the conventional op-amp Wien bridge versions.

Comments on "Active-R realization of bilinear RL impedances and their application in a high-Q parallel resonator and external capacitorless oscillator"

Realization of bilinear RL impedances use only one operational amplifier (OA) and one or two resistors is proposed. These are based on the single-pole model of the OA. Applicabilities of these one-port active-R grounded inductances in a parallel capacitor tuned high-Qresonator and in a new external capacitorless sine-wave oscillator are also reported tosether with experimental verification.

A new equal-valued grounded-capacitor resonator realization using current conveyor

Using a second generation current conveyor (CC II), a new resonator network containing a resistance (R)-capacitance (C)-frequency dependent negative resistance (D) series configuration is proposed. The network is canonic and both the equal-valued capacitors are grounded. ω0and Q of the resonator have been shown to be practically insensitive to changes in active parameters.

New grounded-capacitor ideal differentiators

A general scheme is presented in which a grounded-capacitor ideal integrator (GCII) function is reciprocated to realize a grounded-capacitor ideal differentiator (GCID) function and vice versa. Some new single-amplifier grounded-capacitor ideal differentiator structures are also reported.

High-selectivity grounded capacitor bandpass/low-pass filters using the operational amplifier pole

Using the single-pole model of the operational amplifier (OA) a grounded capacitor network has been analyzed to yield either a bandpass or a low-pass function by adjustment of a single resistor. The bandpass/low-pass filters are suitable for high selectivity applications at extended frequency ranges with the advantage of independent adjustment of pole-frequency, pole-Q factor, and midband/passband transmission gain. The network has low sensitivity to all the circuit parameters. The experimental results are quite in agreement with the analysis.

Comments on "Precise noninverting operator realization with high-resistive input impedance"

In the classical shunt feedback op-amp realization of mathematical operators of integration, differentiation, etc., the input impedance can be limited and nonresistive in some cases (as in differentiators). Alternative methods are discussed for realizing the transfer Z2/Z1without sign inversion, and with high-resistive input impedance in all cases.

A high-input impedance inverting/noninverting active gain block

A two-amplifier two-resistor configuration is proposed which is suitable for applications as a general gain block of either inverting on noninverting types. The structure has high-input impedance and the gain can be adjusted by a grounded resistor.

Novel active-R ideal frequency-dependent negative-resistance simulation

A novel structure for the simulation of an ideal frequency-dependent negative-resistance (FDNR) element based on the single-pole rolloff characteristics of the operational amplifier is reported. The structure uses only operational amplifiers and a resistor.

Integrable insensitive subaudio-frequency sine-wave generator using DVCVS/DVCCS

A novel sine-wave oscillator using the differential voltage-controlled voltage/current source (DVCVS/DVCCS) with only two resistors and two grounded capacitors is proposed. The oscillator is tunable in the subaudio ranges by a grounded resistor in a practically insensitive manner.