New current-mode current-controlled universal filter with single input and three outputs

In this study, a new current-mode current-controlled universal filter with single input and three outputs is presented. The proposed circuit uses single-output current controlled conveyors (CCCIIs) and can simultaneously realize lowpass, bandpass and highpass filter functions all at high impedance outputs. Realization of notch and allpass responses does not require additional active elements. The circuit enjoys independent current-control of the parameters ω₀ and ω₀/Q without disturbing the gains of the lowpass, bandpass and highpass filters. Both its active and passive sensitivities are low.     

A new OTA-C current-mode biquad filter with single input and multiple outputs

A new current-mode biquad-filtering circuit with single input and multi-outputs based on operational transconductance amplifier (OTA) is presented using three OTAs, two grounded capacitors and one grounded resistor, it can simultaneously realize second-order lowpass, bandpass, highpass, notch and allpass filters. The characteristic parameters can be adjusted orthogonally by a bias current of OTA and all capacitors are gounded. Morever, the circuit enjoys low sensitivities.     

Universal current filter with single input and three outputs using MOCCIIs

A universal current-mode biquadratic filter with single input and three outputs using three multiple outputs second-generation current conveyors (MOCCIIs), four resistors and two grounded capacitors is presented. The filter can realize lowpass, highpass and bandpass responses, simultaneously. The notch and allpass responses can also be obtained by interconnection of relevant output currents.     

Universal active current filter with single input and three outputs using CCIIs

A universal active filter with current gain and with single input and three outputs using second-generation current conveyors (CCIIs) is presented. The proposed circuit offers the following advantageous features: independent control of omega /sub 0/, Q and current gain through separate grounded resistors, use of only two grounded capacitors making it ideal for integration, and no requirements of critical matching condition/cancellation constraints in realising the lowpass, bandpass, highpass and notch filter responses.<>     

High output impedance current-mode universal filter employing dual-output current-controlled conveyors and grounded capacitors

A novel current-controlled two-input three-output current-mode universal filter, which employs only three dual-output controlled-controlled current conveyors (DOCCCIIs) and two grounded capacitors, is presented in this paper. The proposed configuration provides inverting-type lowpass, noninverting-type lowpass, inverting-type bandpass, noninverting-type bandpass, highpass, bandstop and allpass current responses at a high impedance terminal, which enable easy cascadability. The filter also offers an independent electronic control of the natural frequency ω_o and the parameter ω_o/Q through adjusting the bias current of the DOCCCII. No critical matching condition is required for realizing all the filter responses, and all the incremental parameter sensitivities are low. The performances of the proposed circuit are simulated with PSPICE to confirm the presented theory.     

Current-tunable current-mode multifunction filter based on dual-output current-controlled conveyors

In this paper, a current-tunable current-mode multifunction filter with two inputs and two outputs employing only four dual-output current-controlled conveyors (DO-CCCIIs) and two grounded capacitors is proposed. By appropriately connecting the input and output terminals, the proposed circuit can provide lowpass, bandpass, highpass, bandstop and allpass current responses. The filter also offers an independent electronic control of the natural frequency (ω_o) and the quality factor (Q) through adjusting the bias currents of the DO-CCCIIs. No critical matching conditions are imposed for realizing all the filter responses, and all the incremental parameter sensitivities are low. The characteristics of the proposed circuit are simulated using PSPICE to confirm the theory.     

Low component current-mode universal filter

A low component current-conveyor based current-mode universal filter with one input and three outputs is presented. The filter can simultaneously realise lowpass, highpass and bandpass responses. Realisation of notch and allpass responses does not require additional active elements. The proposed circuit enjoys low active and passive sensitivities     

Universal three input and one output current-mode filter withoutexternal passive elements

A new current-mode universal filter is proposed. The filter uses only operational amplifiers and operational transconductance amplifiers (OTAs) and can realise lowpass, highpass, bandpass, notch and allpass responses without changing circuit topology. The parameters ω₀, ω₀/Q₀, and the gain can be electronically tuned by adjusting the bias currents of the OTAs. The proposed circuit has low sensitivity     

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.     

数字可编程的电流模式通用双二阶滤波器

本文提出了一种新的基于MOCCII的等电容和等电阻电流模式通用双二阶滤波器综合方法.通过对双二阶通用滤波传输函数进行分析将其分解成能用无损积分器实现的表达式,完成电路综合.该滤波电路包含4个有源器件、8个接地无源元件,通过控制数字可编程开关在输出端得到电流模式二阶低通、高通、带通、带阻和全通五种滤波功能.电路有很低无源灵敏度.文中对滤波器进行了PSPICE模拟验证.     

New voltage-model/current-mode universal biquad filter using unity-gain cells

A new universal biquad filter is presented which can realize all the five standard filter functions namely lowpass, bandpass, highpass, notch and allpass in voltage-mode (VM) as well as in current-mode (CM) employing only unity-gain cells (i.e. voltage followers and current followers) as active elements. Explicit VM/CM outputs are available from low output impedance terminals and high output impedance terminals, respectively. The workability of the proposed universal biquad, realized with CMOS unity-gain cells, is established by SPICE simulations.     

New electronically tunable current-mode universal biquad filter using translinear current conveyors

In this study, a new electronically tunable current-mode universal filter with two inputs and two outputs employing one translinear current conveyor, one translinear current conveyor with controlled current gain and two grounded capacitors is presented. The proposed circuit offers the following attractive features: realisation of low-pass, band-pass, high-pass, band-stop and all-pass current responses from the same configuration; employment of the minimum active and passive components; no requirement of component matching conditions; independent current-control of the parameters natural frequency (ω_o) and quality factor (Q); low active and passive sensitivities; and high impedance output. The characteristics of the proposed circuit are simulated using PSPICE to confirm the theory.     

Versatile current-mode universal biquadratic filter using DO-CCIIs

In this article, a new three-input and three-output versatile current-mode universal biquadratic filter is proposed. The circuit employs three dual-output current conveyors (DO-CCIIs) as active elements together with three grounded resistors and two grounded capacitors. The proposed configuration exhibits low-input impedance and high-output impedance which is important for easy cascading in the current-mode operations. It can be used as either a single-input and three-output or three-input and two-output circuit. In the operation of single-input and three-output circuit, the lowpass, bandpass and bandreject can be realised simultaneously, while the highpass filtering response can be easily obtained by connecting appropriated output current directly without using addition stages. In the operation of three-input and two-output circuit, all five generic filtering functions can be easily realised by selecting different three input current signals. The filter permits orthogonal controllability of the quality factor and resonance angular frequency, and no component matching conditions or inverting-type input current signals are imposed. All the passive and active sensitivities are low. HSPICE simulation results based on using TSMC 0.18?µm 1P6M CMOS process technology and supply voltages ±0.9?V to verify the theoretical analysis.     

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     

一种新颖的电流模式双二阶OTA-C滤波器设计

提出了一种新颖OTA-C实现的电流模式双二阶通用滤波器。该滤波器具有三个输入端和一个输出端,通过选择不同的输入信号即能实现低通、高通、带通、带阻和全通五种滤波器功能。电路结构简单、中心频率和品质因数可调,灵敏度低,均为0.5。理论分析和SPICE仿真表明所提电路方案正确可行。     

Insensitive current-mode universal filter using dual output current conveyors

A new current-mode universal filter with single input and three outputs employing only three dual output current conveyors and five grounded passive elements is presented. The proposed filter realizes three filter functions simultaneously, all at high impedance outputs. No component matching is required and all the passive and active sensitivities are low. Furthermore, the filter can also realize the notch and all-pass responses. Orthogonal control of the natural angular frequency and the quality factor is achieved.     

Tunable versatile current-mode universal filter based on plus-type DVCCs

This paper presents a new tunable versatile current-mode universal filter with four inputs and three outputs. The proposed configuration employs three plus-type differential voltage current conveyors, two grounded capacitors and three grounded resistors. Its high impedance outputs enable easy cascading in current-mode operation. The circuit can be used as either a single-input and three-output or four-input and two-output. In the operation of single-input and three-output circuit, the bandpass, highpass and bandreject filtering responses can be realized simultaneously. In the operation of four-input and two-output circuit, both inverting and non-inverting type lowpass, bandpass, highpass, bandreject and allpass filtering responses can be simultaneously realized by selecting different four input current signals. The filter permits orthogonal controllability of the quality factor and resonance angular frequency by adjusting the grounded passive components. No component matching condition is required for realizing all the filter responses, and all the passive and active sensitivities are low. HSPICE simulation results based on using TSMC 0.18 μm 1P6M CMOS process technology and supply voltages ±0.9 V to verify the theoretical analysis.     

SITO electronically tunable high output impedance current-mode universal filter

A novel current-mode (CM) single-input and three-output (SITO) universal filter using two second generation current controlled conveyors (CCCIIs), one current follower (CF) and two capacitors is presented. The circuit is fully programmable and implements all the five generic filtering functions. The lowpass (LP), bandpass (BP), and highpass (HP) functions can be realized simultaneously while Notch (BS) and allpass (AP) responses can be implemented simply by connecting the appropriate node currents without requiring additional elements. The availability of currents at high impedances, facilitate cascadibility feature. The filter performance factors ω₀ and ω₀/Q are electronically tunable through separate bias currents of the CCCIIs. SPICE simulation results are included to confirm the workability of the proposed circuit.     

Electronically tunable current-mode second-order universal filter using minimum elements

A new electronically tunable universal filter with single-input, triple-output employing only four elements (two capacitors and two negative-type second generation current controlled conveyors (CCCII)) is proposed. The proposed filter realises three basic filter functions simultaneously: lowpass, highpass and bandpass. The validity of the proposed filter is verified through PSPICE simulations.