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It is well known that there is an increasing trend on the design of low-voltage low-power circuits due to the requirement of efficient portable electronic systems with long battery lifetime. For analog circuits, higher biasing current is needed to obtain the same performance with low supply voltages which, however, results in increasing the power consumption. On the other hand, lower biasing current restricts the dynamic range of the circuit, whereas with low supply voltages it is hard to keep all the transistors in saturation region. Thus, design techniques for low-voltage low-power operation are very important for analog circuit designers. In this Special Issue we deal with low-voltage low-power analog devices and their applications

The signal handling capability of the filters is called dynamic range. In this paper, a topological form for the synthesis of filters with high dynamic range is proposed. A biquad notch/all-pass filter is shown in conformity with the given topological form. It is shown that there is a trade-off between dynamic range and high input impedance property. The presented circuit is compared with other notch filters in the literature. It has less number of components, better high-frequency response and dynamic range compared to others. Since the circuit includes a minimum number of resistors, it can easily provide electronically tunable circuits through resistor/controlled current conveyor replacement. Simulations are performed to verify the theoretical results. Routh-Hurwitz stability analyses are also given.

Analog circuit desioners have usually focused on the design of circuits employing a minimum number of components, occupying less area and dissipating less power. However, some important issues such as signal limitations and especially stability problems of the analog circuits have not received considerable attention in the literature. Hence, the work described in this paper deals with the stability problems of two new current-mode analog filters employing multiple output current controlled conveyors (MOCCCIIs). Toward that end, a single pole model is replaced for each non-ideal current gain of the MOCCCIIs. Both of the novel universal current-mode active-C filters can simultaneously realize low-pass, band-pass and high-pass/notch filter responses. SPICE and MATLAB simulation results are given to verify the theoretical analysis. (C) 2006 Elsevier GmbH. All rights reserved.

A universal current-mode active-C filter simultaneously realizing low-pass, band-pass and high-pass responses is proposed. The filter can also realize notch and all-pass responses with interconnection of relevant output currents. The presented filter employs four second-generation current controlled conveyors (CCCIIs) as active elements and only two capacitors as passive elements. The proposed active-C filter can be tuned electronically, and has low element sensitivities.

In this paper, a voltage-mode full-wave rectifier employing plus-type second-generation current conveyors (CCII+s) and enhancement-mode n-channel metal-oxide semiconductor field-effect transistors (MOSFETs) is proposed. The presented circuit requires no passive components, and is suitable for high frequency applications. The proposed full-wave rectifier circuit is simulated using HSPICE to verify the theoretical analysis.

In this paper, new floating immittance function simulators employing second-generation current controlled conveyors are proposed. The first four of the presented circuits employ only a single grounded capacitor as passive component and can realize either a negative or a positive floating inductor or capacitor. The last two of the proposed circuits do not employ passive components and can realize either negative or positive floating resistances. All of the proposed circuits do not require passive element matching. As an application, a third-order butterworth filter is realized using the proposed positive floating inductance simulator. SPICE simulation results and large signal behavior of the filter are included.

An active circuit suitable for realizing floating inductance, capacitance, FDNR and admittance converter depending on the selection of passive elements of the circuit is presented. The proposed circuit employs only two dual output second-generation current conveyors (DO-CCIIs) and does not require passive element matching. The proposed network has a grounded capacitor for the floating inductance and capacitance simulation. Frequency performance of the circuit is tested using SPICE.

In this paper, new circuits for realizing current-mode and voltage-mode proportional plus integral plus derivative (PID) controllers, proportional plus integral (PI) and proportional plus derivative (PD) controllers employing only plus-type second-generation current conveyors (CCII+s) as active elements are presented. All of the proposed PID, PI and PD controllers have unmatched passive elements, all of which are grounded. The proposed controllers employ reduced number of active and passive components with respect to traditional op-amp based PID, PI and PD controllers. In particular, the proposed current-mode and voltage-mode PD and PI controllers employ minimum number of active and passive components. A closed-loop control system employing the proposed current-mode PID controller is designed and simulated using SPICE.

A new circuit employing second-generation current conveyors (CCIIs), and unmatched resistors for converting a grounded immittance to the corresponding floating immittance with either positive or negative adjustable multiplier, is presented. Moreover, the proposed circuit can also realize a synthetic floating inductance employing a grounded capacitor depending on the passive element selection. Simulation results using 0.35 mu m TSMC CMOS technology parameters are given.

All-pass filters are widely used to shift the phase of an analog signal without altering its magnitude. In this study, a new realization of all-pass filter using one current controlled conveyor (CCCII), one operational amplifier (OP-AMP) and two capacitors is presented. The proposed circuit does not use any resistors thus it is suitable for easy integration. Also the pole frequency of the proposed circuit can be tuned electronically. Simulation results are included to verify theory.

In this paper, a floating inductance and frequency-dependent negative resistance (FDNR) depending on the passive element selection is presented. The proposed circuit employs only plus-type second-generation current conveyors (CCII+s) as active elements, together with two resistors and two capacitors for realizing floating inductance and FDNR. Both of the capacitors in the floating inductance realization are grounded. Also, electronically tunable floating FDNR is obtained with the proposed circuit. The nonideality effects of the current conveyors on the proposed circuit are given. The proposed circuit is used in a low-pass ladder filter, and simulated with SPICE to exhibit its performance.

In this study, we present a new topology for realizing a grounded inductor employing only a single current conveyor, called a negative-type modified inverting second-generation current conveyor (MICCII-), and a minimum number of passive components, two resistors, and one capacitor. The non-ideality effects of the MICCII- on a simulated inductor are investigated. To demonstrate the performance of the presented inductance simulator, we use it to construct a third order Butterworth high-pass filter and a parallel resonant circuit. Simulation results are given to confirm the theoretical analysis.

Minaei, Shahram (Dogus Author) A second-order multifunction voltage-mode filter with three inputs and one output, is discussed. The filter uses a novel current conveyor called balanced dual input-dual output current conveyor and minimum number of passive elements. Also the filter does not require passive element matching. The parameters angular resonance frequency and quality factor can be adjusted by changing the values of the resistors orthogonally.

A new realization of floating inductance and two R-L impedance simulators are presented, respectively employing three and two first generation current conveyors (CCI)s as active elements. All of the circuits use only plus type (CCI+)s and minimum number of passive elements. The circuits do not require component matching. The performances of the circuits are tested using SPICE simulation program.

In this paper new active only current-mode integrator and differentiator with electronically tunable time constants are described. They are composed of one operational amplifier (OA) and two operational transconductance amplifiers (OTAs), and are suitable for monolithic implementation either with CMOS or bipolar technologies. No realizability conditions are imposed for the proposed circuits and all of the active sensitivities are low. The performances of the circuits are demonstrated on the PSPICE platform.

In this paper a new floating inductance simulator employing only active elements is proposed. The proposed circuit uses one internally compensated operational amplifier and one dual output current controlled conveyor (CCCII). The simulated inductance value can be controlled electronically by adjusting the bias current of the CCCII. No component matching constraints are imposed for the simulator and all active sensitivities are low. The performance of the circuit is demonstrated on a fourth-order elliptic filter using a SPICE simulation program

In this paper two new current-mode multifunction filters are presented. The proposed circuits are composed of two internally compensated operational amplifiers (OAs) and three dual-output operational transconductance amplifiers (OTAs), without using external passive elements. Each proposed multifunction filter can realize band-pass, bandstop, and lowpass or highpass responses simultaneously all at high output impedances. No matching conditions are required. The circuits are suitable for monolithic implementation either with CMOS or bipolar technologies. All of active sensitivities are low. The performances of the circuits are confirmed through a SPICE simulation program using the model parameters of 0.5 mum MIETEC CMOS technology.

Telif hakkı yayıncıya ait. In this paper a new trans-impedance mode multifunction filter using opamp compensation poles is presented. The proposed circuit is composed of two internally compensated operational amplifiers (OAs) and four single-output operational transconductance amplifiers (OTAs), without using any external passive elements. The proposed multifunction filter can realize lowpass, bandpass and highpass responses simultaneously. Lowpass and bandpass responses have low output impedances. No matching condition is required. The circuit is suitable for monolithic implementation either with CMOS or bipolar technologies. All of the active sensitivities are low. The performance of the circuit is tested by using SPICE simulation program. IEEE

In this paper a new current-mode multifunction filter using opamp compensation poles is presented. The proposed circuit is composed of two internally compensated operational amplifiers (OAs) and five single output operational transconductance amplifiers (OTAs), without using external passive elements. The proposed multifunction filter can realize lowpass, bandpass, highpass and bandstop responses simultaneously all at high output impedances. The circuit is suitable for monolithic implementation either with CMOS or bipolar technologies. All of active sensitivities are low. The performances of the circuits are tested using SPICE simulation program. IEEE CAS Soc; Univ Zagreb, Fac Elect Engn & Comp; Portland State Univ, Elect & Comp Engn Dept; IEEE Reg 8; Croatian Acad Sci & Arts; Ericsson; IBM; HP Invent; Hrvatski Telekom; Croatia Airlines

In this paper a new configuration for the realization of first-order current-mode all-pass filters with high output impedance is presented. It can realize first-order allpass filtering function using two current controlled conveyors (CCCIIs) connected to four RC one-part elements. Eight different realizations for the proposed configuration are given in tabular form, which exhibit identical transfer functions but differ in the number of passive Components, component matching constraints possibility of electronically gain adjustment and other properties. PSPICE simulation results are given to confirm the theoretical analysis. IEEE; Agcy Natl Reglementat Telecommun; Minist Enseignenment Super Rech Sci; Secretatiat Etat Aupres Minist Enseignement Super Rech Sci Charge Rech Sci; SEPTI; CNRST; Rectorat Univ Mohammed V-Agdal; Sicotel; Silvaco Data Syst; STMicroelectr; Mentor Graph; Commune Agda/Ryad; Off Natl Eau Potable; Barid El Maghreb