Rajeshwari Pandey

OTRA Based Voltage Mode Third Order Quadrature Oscillator

Two topologies of operational transresistance (OTRA) based third order quadrature oscillators (QO) are proposed in this paper. The proposed oscillators are designed using a combination of lossy and lossless integrators. The proposed topologies can be made fully integrated by implementing the resistors using matched transistors operating in linear region, which also facilitates electronic tuning of oscillation frequency. The nonideality analysis of the circuit is also given and for high frequency applications self-compensation can be used. Workability of the proposed QOs is verified through PSPICE simulations using 0.5 μm AGILENT CMOS process parameters. The total harmonic distortion (THD) for both the QO designs is found to be less than 1%.

Approach for third order quadrature oscillator realisation

This paper presents a new approach for third order quadrature oscillator (QO) realisation. It uses a high pass filter and differentiator connected in a feedback loop. A differential voltage current conveyor transconductance amplifier (DVCCTA) is employed to verify the proposed approach. Two circuit topologies of QO have been proposed. Both the topologies utilise two DVCCTA and three grounded capacitors. In addition, the first topology employs a single resistor while the second makes use of two resistors. The circuits exhibit orthogonal control on frequency and condition of oscillation. The quadrature current outputs are available at high output impedance and voltage outputs are also present. The theoretical proposition has been verified through SPICE simulations using 0.25 μm Taiwan semiconductor manufacturing company (TSMC) complementary metal oxide semiconductor (CMOS) technology parameters. Experimental results are also included which corroborate the theoretical propositions and simulated results.

Current Mode Full-Wave Rectifier Based on a Single MZC-CDTA

This paper presents a current mode full-wave rectifier based on single modified Z copy current difference transconductance amplifier (MZC-CDTA) and two switches. The circuit is simple and is suitable for IC implementation. The functionality of the circuit is verified with SPICE simulation using 0.35 μm TSMC CMOS technology parameters.

Operational transresistance amplifier-based multiphase sinusoidal oscillators

Multiphase sinusoidal oscillator circuits are presented which utilize Operational Transresistance Amplifier (OTRA) as the active element. The first circuit produces n odd-phase oscillations of equal amplitudes and equally spaced in phase. The second circuit is capable of producing n odd- or even- phase oscillations equally spaced in phase. An alternative approach is discussed in the third circuit, which utilizes a single-phase tunable oscillator circuit which is used to inject signals into a phase shifter circuits. An automatic gain control (AGC) circuit has been implemented for the second and third circuit. The circuits are simple to realize and have a low component count. PSPICE simulations have been given to verify the theoretical analysis. The experimental outcome corroborates the theoretical propositions and simulated results.

MOS-C Third Order Quadrature Oscillator Using OTRA

In this paper a voltage mode third order quadrature oscillator is proposed. The proposed filter is suitable for MOS-C implementation making oscillation frequency electronically tunable. The non-ideality analysis of the circuit is also given and for high frequency applications self compensation can be used. PSPICE simulations have been included to demonstrate the workability of the proposed quadrature oscillator. Simulations are carried out using 0.5 ìm CMOS process parameters provided by MOSIS (AGILENT).

Novel grounded inductance simulator using single OTRA

In this paper, a method to realize a grounded inductor using single operational transresistance amplifier is presented. The simulated inductance value can be controlled independent of realizability condition. The non-ideality analysis of the circuit is also given. The workability of the proposed simulated inductance is demonstrated through two applications namely, a band pass filter and an oscillator. PSPICE simulation and experimental results agree well with the theoretical values. Copyright

Design of CDTA and VDTA Based Frequency Agile Filters

This paper presents frequency agile filters based on current difference transconductance amplifier (CDTA) and voltage difference transconductance amplifier (VDTA). The proposed agile filter configurations employ grounded passive components and hence are suitable for integration. Extensive SPICE simulations using 0.25 μm TSMC CMOS technology model parameters are carried out for functional verification. The proposed configurations are compared in terms of performance parameters such as power dissipation, signal to noise ratio (SNR), and maximum output noise voltage.

New topologies of lossless grounded inductor using OTRA

Two alternate topologies of lossless grounded inductor have been proposed using operational transresistance amplifier (OTRA). Three applications using the proposed inductors are also included. PSPice simulation and experimental results have been included to demonstrate the performance and verify the theoretical analysis.

Multiphase sinusoidal oscillators using Operational Trans-Resistance Amplifier

In this paper Operational Trans-Resistance Amplifier (OTRA) based multiphase sinusoidal oscillator circuits are presented. The first circuit produces n odd-phase oscillations of equal amplitudes and equally spaced in phase. The second circuit is capable of producing n odd or even phase oscillations equally spaced in phase. An alternative approach is discussed in the third circuit, which utilizes a single phase tunable oscillator circuit which is used to inject signals into a phase shifter circuit. An automatic gain control (AGC) circuit has been implemented for the second and third circuit. The circuits are simple to realize and have a low component count. PSpice simulations have been given to verify the theoretical analysis.

Realization of CDTA based frequency agile filter

This paper presents frequency agile filter based on current difference transconductance amplifier (CDTA). The agile filters used in this work provide high agilty, tunability and quality factor while they are fully integrated configurations and not discrete systems. The use of grounded capacitors and resistor makes these structures suitable for integration. The functional verification is exhibited through extensive SPICE simulations using 0.25μm TSMC CMOS technology model parameters. The performance evaluation is made in terms of power dissipation, signal to noise ratio (SNR) and output noise.