Sudhanshu Maheshwari

Simple first order all-pass section using a single CCII

A novel first order all-pass section using a single second generation current conveyor is given. In addition the circuit uses two resistors and only one capacitor. The circuit is also realized with a translinear conveyor. The latter circuit uses only one external resistor and a capacitor. The proposed circuits are verified using PSPICE with attractive results.

Novel first order all-pass sections using a single CCIII

Two novel first order voltage-mode all-pass sections using a single third generation current conveyor (CCIII) are given. In addition the first circuit uses three resistors and one capacitor and the second circuit which is derived from the first circuit uses two resistors and one capacitor. A current-mode first order all-pass section requiring one capacitor and one resistor is also proposed. SPICE simulation results are incorporated to verify the theory.

New voltage and current-mode APS using current controlled conveyor

A first-order all-pass section (APS) is introduced employing a single second-generation current conveyor and three passive components. The translinear conveyor version of the circuit employing only two passive components is also proposed. A fully tunable version of the circuit employing two current controlled conveyors (CCCIIs) and a single capacitor is finally derived. All the three versions of APS can be operated both in voltage as well as current mode without changing the circuit configuration. As an application, a quadrature oscillator providing two quadrature currents and two phase-shifted voltage outputs simultaneously, is realized using the proposed APS. RSPICE simulation results for the translinear-C APS, and the translinear-C quadrature oscillator are included to verify the theory.

Current-mode third-order quadrature oscillator

The author presents a current-mode current-controlled third-order quadrature oscillator circuit synthesised from a simple yet novel approach using basic bilinear blocks. The new circuit is more compact than the other third-order oscillators available in the literature and enjoys non-interactive frequency control, use of grounded capacitors and availability of both quadrature current and voltage outputs. PSPICE simulations are performed for the verification of the new circuit. Experimental evidence is further given for completeness sake. The new basic scheme is also useful for realising a quadrature oscillator using other active elements as well.

High input impedance VM-APSs with grounded passive elements

Three new circuit topologies for first-order all-pass filters, each with two variations, realising six new first-order voltage-mode all-pass sections are proposed. Each circuit employs two differential voltage current conveyors and three grounded passive components, ideal for IC implementation. All the circuits possess high input impedance, which is a desirable feature for voltage-mode circuits. As an application, a new quadrature oscillator circuit is realised using one of the proposed all-pass circuits. PSPICE simulations using 0.5 mum CMOS parameters confirm the validity and practical utility of the proposed circuits

Analogue signal processing applications using a new circuit topology

New circuit topology for realising simple voltage-mode analogue functions, using one differential voltage current conveyor with positive output and a maximum of three passive elements, is proposed. The new topology can realise nine circuits including amplifier, integrator, differentiator and first-order all-pass filters. All the circuits show wide linearity, low total harmonic distortion (THD) and a simple realisation. Non-ideal and parasitic study is also given. As application examples, the new analogue blocks are used in realising biquad filter and third order quadrature oscillator. The proposed theory is validated by PSPICE simulation results as well as experimental results using AD844s. The catalogue of simple circuits along with their applications makes the work a future prospect for adoption to IC implementation by analogue IC producers.

Simple first-order translinear-C current-mode all-pass sections

A first-order translinear-C current-mode (CM) all-pass section (APS) using two current-controlled conveyors (CCCII) and a single capacitor is given. A canonical CM-APS using only one dual-output CCCII and one capacitor is also derived from the proposed configuration. The circuits are analysed for the non-idealities of CCCII and possess attractive sensitivity performance. The proposed circuits are electronically tunable over a wide frequency range. RSPICE simulation results for ac analysis, transient analysis and harmonic distortions are incorporated to verify the theory.

Current Controlled Current Differencing Buffered Amplifier: Implementation and Applications

A new four terminal current-controlled active element is introduced, where parasitic resistances at two current input ports are controlled leading to the definition of current-controlled current differencing buffered amplifier. Bipolar implementation and as application current-mode band-pass filter circuits are proposed. Simulation results using real device parameters are included, which show device bandwidth of 35 MHz, low total harmonic distortions, and tuning over a wide current range.

High-input low-output impedance all-pass filters using one active element

This study presents four new voltage mode first-order all-pass filters using a newly developed single Dual-X current conveyor with buffered output. The proposed circuits possess high-input impedance, low-output impedance and require either two or three passive elements. An application of new circuits is also given in realising the quadrature oscillator. Non-ideal and sensitivity analysis is also performed. The circuit performances are depicted through PSPICE simulations, which show good agreement to theoretical anticipations. Possible realisation using AD-844 along with some experimental results are also given for completeness sake. The new circuits are expected to enhance the already-existing knowledge on the subject.

High output impedance current-mode all-pass sections with two grounded passive components

Two new first-order, current-mode all-pass sections, each with high output impedance and requiring only two grounded passive components along with a differential voltage current conveyor, are presented. The new circuits require no matching conditions for the realisation of current transfer functions and are simpler than most of the recently available circuits. The effect of parasitics and non-idealities is also considered. PSPICE simulations using 0.5 µ CMOS parameters confirm the validity and practical utility of the proposed circuits. A typical application in realising a new current-mode quadrature oscillator is given. A four-phase quadrature oscillator with high impedance outputs is also given.