MO-CCCII Based Current-Mode Fractional-Order Universal Filter

In this study, a new current-mode fractional-order universal filter is presented by using multi mode second generation current controlled current conveyors (MO-CCCII). The circuit consists of two resistors and grounded capacitors with only three MO-CCCII. This is accomplished with a fractional-order capacitor, also known as a stationary phase element, to form a fractional-order filter. The value of this capacitor depends only on the fractional-order [Formula: see text]. The proposed filter is designed as fractional [Formula: see text], 1.8 and 1.9 order. The fractional-order capacitor is obtained using the Foster-I [Formula: see text] network circuit. The filter is simulated with BJT-based MO-CCCII using PSPICE simulation program for the filter to verify the theory and to show the performance of it. The fractional-order universal filter outputs are provided the desired stop band attenuation and more precise control of attenuation slope. Through the fractional-order parameter, it is revealed that the filter designer can fully meet the requirements of the filter. It also offers design flexibility since the frequencies of interest depend not only on circuit components but also on fractional-order parameters.

A Compact Size Wideband RF-VGA Based on Second Generation Controlled Current Conveyors

This paper presents a methodology to design a wideband radio frequency variable gain amplifier (RF-VGA) in a low-cost SiGe BiCMOS 0.35 μm process. The circuit uses two Class A amplifiers based on second-generation controlled current conveyors (CCCII). The main feature of this circuit is the wideband input match along with a reduced NF (5.5–9.6 dB) and, to the authors’ knowledge, the lowest die footprint reported (62 × 44 μm2 area). The implementation of the RF-VGA based on CCCII allows a wideband input match without the need of passive elements. Due to the nature of the circuit, when the gain is increased, the power consumption is reduced. The architecture is suitable for designing wideband, low-power, and low-noise amplifiers. The proposed design achieves a tunable gain of 6.7–18 dB and a power consumption of 1.7 mA with a ±1.5 V DC supply. At maximum gain, the proposed RF-VGA covers from DC up to 1 GHz and can find application in software design radios (SDRs), the low frequency medical implant communication system (MICS) or industrial, scientific, and medical (ISM) bands.

DO-CCII/DO-DVCC Based Electronically Fine Tunable Quadrature Oscillators

In this paper, a new quadrature oscillator employing two dual output second-generation current conveyors (DO-CCIIs), two resistors and two grounded capacitors is proposed. The proposed quadrature oscillator has only resistors but no capacitors connected in series to [Formula: see text] terminals of the DO-CCIIs; thus, it can be operated at high frequencies. It can be tuned electronically by replacing dual output second-generation current controlled current conveyors instead of DO-CCIIs and removing both resistors. It can provide two output currents in opposite sign. Nevertheless, its resonance frequency can be simultaneously controlled by two resistors. Also, a dual output differential voltage current conveyor (DO-DVCC) based quadrature oscillator which employs a canonical number of only grounded passive components is proposed. A number of simulation results based on SPICE program and an experimental test result are included to exhibit performance, workability and effectiveness of the proposed quadrature oscillators.

Tuneable Current Mode RMS Detector

A new realization of RMS detector, employing two CCCIIs (controlled current conveyors), metal-oxide-semiconductor transistors and single grounded capacitor is present in this paper, without any external resistors and components matching requirements. The proposed circuit can be applied in measuring the RMS value of periodic, band-limited signals. The proposed circuit is very appropriate to further develop into integrated circuits. The errors related to the signal processing and errors bound were investigated and provided. To verify the theoretical analysis, the circuit PSpice simulations have also been included, showing good agreement with the theory.

Comparative Study of Resistorless Filters Using Differential Voltage Current Controlled Current Feedback Operational Amplifiers and Differential Voltage Current Controlled Current Conveyors

Differential Voltage Current Controlled Current Feedback Operational Amplifier is an attractive active element for realizing resistorless filters with a minimum active component count. This is verified through a design example, where a 3rd-order leapfrog filter has been realized using the AMS 0.35 μm CMOS process design kit. The performance of the Differential Voltage Current Controlled Current Feedback Operational Amplifier filter is evaluated and compared with that obtained by the corresponding filter, where Differential Voltage Current Controlled Current Conveyors have been employed.

VOLTAGE-CONTROLLED CURRENT CONVEYORS: APPLICATIONS TO RESISTANCE-CONTROL

Variable gain Current Conveyors have been proposed to allow control of the value on fixed resistors. In this paper, procedures will be described, taking into account the stability of different configurations when a practical CCII- is applied. Correction circuits will modify the control range. Frequency response and transients are shown.