High output impedance current-mode universal biquadratic filters with five inputs using multi-output CCIIs

Three current-mode universal biquadratic filters each with five input terminals and one output terminal are presented. The first proposed circuit uses three multi-output second-generation current conveyors, two grounded capacitors and three resistors. This circuit offers the following advantageous features: orthogonal controllability of resonance angular frequency and quality factor, high output impedance, the versatility to synthesize all standard filter types without component matching condition and using grounded capacitors. The second proposed circuit uses three multi-output second-generation current conveyors, two grounded capacitors and two resistors. This circuit offers the following advantageous features: using minimum passive components, high output impedance, the versatility to synthesize all standard filter types without component matching condition and using grounded capacitors. The third proposed circuit uses three multi-output second-generation current conveyors, two grounded capacitors and three grounded resistors. This circuit offers the following advantageous features: the versatility to synthesize all standard filter types, high output impedance and using only grounded passive components. Each of the proposed circuits can get five kinds of filter functions by using only one current input signal.     

High Input Impedance Voltage-Mode Universal Biquadratic Filter with Three Inputs and Six Outputs Using Three DDCCs

A new high input impedance voltage-mode universal biquadratic filter with three input terminals and six output terminals is presented. The proposed circuit uses three plus-type differential difference current conveyors (DDCCs), three resistors, and two grounded capacitors. The proposed circuit can realize all the standard filter functions, namely, lowpass, bandpass, highpass, notch, and allpass, simultaneously, without component matching conditions. The proposed circuit still offers the features of high input impedance, using only grounded capacitors, and orthogonal controllability of resonance angular frequency and quality factor.     

High Input Impedance Voltage-Mode Universal Biquadratic Filter with One Input and Five Outputs Using Current Conveyors

A new high input impedance voltage-mode universal biquadratic filter with one input terminal and five output terminals is presented. The proposed circuit uses three differential voltage current conveyors (DVCCs), four resistors, and two grounded capacitors. The proposed circuit can realize all the standard filter functions—lowpass, bandpass, highpass, notch, and allpass—simultaneously, without changing the passive elements. The proposed circuit enjoys the features of high input impedance, orthogonal control of resonance angular frequency and quality factor, use of only grounded capacitors, and low active and passive sensitivities.     

Current-Mode Universal Biquadratic Filter with Five Inputs and Two Outputs Using Two Multi-Output CCIIs

A current-mode universal biquadratic filter with five input terminals and two output terminals is presented. The proposed circuit uses two multi-output second generation current conveyors, two grounded capacitors and three resistors. The new circuit offers the following advantages: use of the minimum number of active components, orthogonal controllability of resonance angular frequency and quality factor, use of grounded capacitors and the versatility to synthesize any type of active filter transfer functions.     

New Universal Filter with One Input and Five Outputs Using Current-Feedback Amplifiers

A new universal voltage-mode second-order filter circuit is presented. The circuit uses five current-feedback operational amplifiers, two grounded capacitors three grounded resistors and three floating resistors. The circuit can realize all the standard filter functions; lowpass, highpass, bandpass, notch and allpass, without changing the passive elements. The proposed circuit enjoys independent grounded-resistance-control of the natural frequency and the bandwidth, low output impedances, high input impedance as well as low active and passive sensitivities.     

A Novel High CMRR High Input Impedance Differential Voltage-Mode KHN-Biquad Employing DO-DDCCs

In this work, a novel circuit configuration for realizing a differential voltage-mode Kerwin-Huelsman-Newcomb (KHN) biquad filter with high common-mode rejection ratio (CMRR) is presented. The proposed circuit is based on using the dual output differential difference current conveyor (DO-DDCC). The circuit uses three DO-DDCCs, two capacitors and five resistors. All the passive elements are grounded, which is important in integrated circuit implementation point of view. The differential voltage input signal is applied to high input impedance terminals, which is important in the voltage-mode operations. SPICE simulation results are included to verify the theory.     

High-Input and Low-Output Impedance Voltage-Mode Universal Biquadratic Filter Using DDCCs

A new three inputs and single output voltage-mode universal biquadratic filter with high-input and low-output impedance using three plus-type differential difference current conveyors, two grounded capacitors and two grounded resistors is presented. The proposed circuit offers the following features: realization of all the standard filter functions, that is, high-pass, bandpass, low-pass, notch, and all-pass filters, no requirements for component matching conditions, the use of only grounded capacitors and resistors, high-input and low-output impedance and low active and passive sensitivities.     

Insensitive current-mode universal filter with minimum componentsusing dual-output current conveyors

A novel universal current-mode active filter with four inputs and one output is presented, which contains only three dual-output current conveyors. Two grounded capacitors and two grounded resistors. The circuit is very advantageous from an integration point of view. The proposed active filter realises all filter responses without any matching conditions at high impedance output and has low passive and active sensitivities     

高输出阻抗多功能电流模式双二阶滤波器

提出了一种基于多输出端差动差分电流传送器的多功能电流模式滤波器电路结构。该电路用三个多输出端差动差分电流传送器，五个或四个接地电阻和两个接地电容，同时实现了反相和，或同相带通和低通或带通和高通滤波响应特性。分析并模拟了所提出的滤波器的传递特性，PSPICE仿真结果表明，所提出的电路方案正确有效。电路具有灵敏度低，输出阻抗高，滤波器固有频率ωo和品质因数Q相互独立可调，多功能的优点，适于实现全集成连续时间滤波器。     

A systematic realization of third-order quadrature oscillator with controllable amplitude

A systematic realization of third-order quadrature oscillator using a voltage-mode non-inverting lowpass filter and a voltage-mode inverting lossless feedback integrator is presented in this paper. The proposed circuit consists of two multiple-output differential voltage current conveyor transconductance amplifiers (MO-DVCCTAs), two grounded resistors and three grounded capacitors. The new circuit provides three quadrature voltage outputs, two high-impedance quadrature current outputs, and one high-impedance current output with controllable amplitude, simultaneously. When the input bias current of the first MO-DVCCTA is a modulating signal, the circuit can generate amplitude modulation or amplitude shift keying signals. The condition of oscillation and the frequency of oscillation can be controlled independently through grounded resistors. The proposed circuit only uses grounded capacitors and grounded resistors, which can be easily implemented as an integrated circuit. The experimental results and H-Spice simulation results are given to confirm the theoretical analysis.     

High input impedance voltage-mode lowpass, bandpass and highpassfilter using current-feedback amplifiers

A new configuration for realising high input impedance lowpass, bandpass and highpass filters simultaneously by using three current-feedback amplifiers, three grounded capacitors, three grounded resistors and one floating resistor is presented. The proposed circuit offers the following features: realisation of lowpass, bandpass and highpass signals from the same configuration, no requirements for component matching conditions, orthogonal control of ω₀ and Q, the use of grounded capacitors, low active and passive sensitivities and low output impedance     

Novel versatile insensitive universal current-mode biquad employing two second-generation current conveyors

A new universal current-mode biquad with two inputs and three outputs or three inputs and two outputs using only two second-generation current conveyors and four grounded/virtual-grounded passive elements is proposed. The proposed circuit has the following advantages: simultaneous realization of five generic current-mode filter signals from the same configuration; no requirements of any cancellation constraints; employment of two grounded capacitors ideal for integrated circuit implementation; employment of two grounded/virtually grounded resistors suitable for voltage control; orthogonal adjustment of ω₀/Q and ω₀ through two separate grounded/virtually-grounded resistors; high output impedance good for cascadability for the current-mode circuits; and low active and passive sensitivities.     

Voltage-mode highpass,bandpass and lowpass filters using two DDCCs

A new configuration for realizing voltage-mode highpass, bandpass and lowpass filters, simultaneously, using two differential difference current conveyors (DDCCs), two grounded capacitors and two grounded resistors is presented. The proposed circuit offers the following features: realization of highpass, bandpass and lowpass signals from the same configuration, no requirements for component matching conditions, the use of only grounded capacitors and resistors, high input impedance, low active and passive sensitivities and simpler configuration due to the use of only two DDCCs and four passive components.     

Versatile multifunction universal voltage-mode biquadratic filter

A new versatile multifunction universal biquadratic filter with four inputs and four outputs employing one differential difference current conveyor, one full differential current conveyor, two grounded capacitors and two grounded resistors is proposed. The proposed configuration can be used as either three-input single-output voltage-mode universal filter with high-input and low-output impedance or single-input four-output voltage-mode multifunction filter with high-input impedance. It still maintains the following advantages: (i) the employment of only two current conveyors, (ii) the employment of only grounded capacitors, (iii) the employment of only grounded resistors, (iv) no need to employ inverting type input signals, (v) no need to impose component choice conditions to realize specific filtering functions and (vi) low active and passive sensitivity performances.     

Universal filter using plus-type CCIIs

A universal second-order filter circuit with voltage gain using only plus-type current conveyors (CCIIs) is presented. The circuit offers several advantages, such as high input impedance, low filter sensitivities to passive elements, use of grounded capacitors and independent control of ω₀, Q and voltage gain with separate grounded resistors. The use of only one type (plus-type or minus-type) of CCII simplifies the configuration     

Single FDCCII-based mixed-mode biquad filter with eight outputs

The transconductance and the transresistance modes might act as the bridge transferring from voltage-mode to current-mode and vice versa, respectively. A novel mixed-mode (including voltage, current, transconductance, and transresistance modes) biquad filter with one input and seven outputs or two inputs and eight outputs is presented. The proposed filter structure only uses a single fully differential current conveyor (FDCCII), three resistors and two grounded capacitors, which are the least components necessary for realizing voltage, current, transresistance modes all five standard filter functions and transconductance-mode band-pass, high-pass filter functions from eight output terminals. Moreover, the new mixed-mode biquad filter still enjoys (i) the employment of two grounded capacitors (attractive for absorbing shunt parasitic capacitance and ideal for IC implementation), (ii) orthogonal control of ω₀ and Q (easy for tunability), and (iii) high output impedance of three current outputs (good for cascadability). H-Spice simulation results verify the theoretical analysis.     

Universal voltage-mode filter using only plus-type DDCCs

Despite the extensive literature on current conveyor-based voltage-mode universal biquads with single input and multiple outputs, no filter circuit has been reported to simultaneously achieve all of the advantageous features: (i) employment of only two differential difference current conveyor (DDCC), (ii) employment only two grounded capacitors, (iii) employment only three resistors, (iv) simultaneously realize voltage-mode low-pass, band-pass, high-pass, notch and all-pass filter signals from the five output terminals, respectively, (v) orthogonal control of ω _o and Q, (vi) low input impedance and can be cascadable (vii) no need to employ inverting type input signals, and (viii) no need to impose component choice except realizing the all-pass filter signal.     

Voltage-mode universal filter with one input and five outputs using DDCCTAs and all-grounded passive components

This paper presents a versatile voltage-mode universal active filter with one input and five output terminals. The proposed circuit is based on using the recently reported active building block, namely differential difference current conveyor transconductance amplifier (DDCCTA). It employs two DDCCTAs as active elements together with two resistors and two capacitors as passive elements, which are all grounded. The circuit simultaneously realizes all the five standard biquadratic filter functions; i.e., lowpass (LP), bandpass (BP), highpass (HP), bandstop (BS) and allpass (AP), without changing circuit topology. The proposed circuit also has the advantage of high-input impedance terminal, and exhibits electronic tunability of its important parameters through the bias current of the DDCCTA as well as low sensitivity performance. PSPICE simulations using 0.5 μm MIETEC CMOS process are used to validate the theoretical predictions.     

一种基于MOCCII的n阶多功能滤波器

提出了一种由MOCCⅡ实现的单输入多输出n阶多功能滤波电路。该电路只需用n个MOCCⅡ、电容和电阻，适当选定输入输出端，可以实现n阶高通、低通、带通和带阻滤波功能。本文所提出的电路结构简单，所用的电容、电阻均接地，易于集成。PIPISE仿真结果进一步证明了理论分析的正确性。     

Quadrature Oscillators with Grounded Capacitors and Resistors Using FDCCIIs

Two current‐mode and/or voltage‐mode quadrature oscillator circuits each using one fully‐differential second‐generation current conveyor (FDCCII), two grounded capacitors, and two (or three) grounded resistors are presented. In the proposed circuits, the current‐mode quadrature signals have the advantage of high‐output impedance. The oscillation conditions and oscillation frequencies are orthogonally (or independently) controllable. The current‐mode and voltage‐mode quadrature signals can be simultaneously obtained from the second proposed circuit. The use of only grounded capacitors and resistors makes the proposed circuits ideal for integrated circuit implementation. Simulation results are also included.