Current-mode Universal Filter Research Articles

0.5 V, Low-Power Bulk-Driven Current Differencing Transconductance Amplifier

This paper presents a novel low-power low-voltage current differencing transconductance amplifier (CDTA). To achieve a low-voltage low-power CDTA, the BD-MOST (bulk-driven MOS transistor) technique operating in a subthreshold region is used. The proposed CDTA is designed in 0.18 µm CMOS technology, can operate with a supply voltage of 0.5 V, and consumes 1.05 μW of power. The proposed CDTA is used to realize a current-mode universal filter. The filter can realize five standard transfer functions of low-pass, band-pass, high-pass and band-stop, and all-pass from the same circuit. Neither component-matching conditions nor input signals of the inverse type are required to realize these filter functions. The current-mode filter offers low-input and high-output impedance and uses grounded capacitors. The natural frequency and quality factor of the filters can be orthogonally controlled. The proposed CDTA and its applications are simulated using SPICE to confirm the feasibility and functionality of the new circuits.

New Z copy- current differencing transconductance amplifier active filter using FinFET transistor based current Mode Universal Filter

This research paper presents the design of an active current mode device named Z-copy- Current Differencing Transconductance Amplifier (ZC-CDTA) in conjunction with FinFET (Fin Field-Effect Transistor) transistors. An input bias current can be used to adjust its parasitic resistances at its two current input ports. It is ideal for use in current-mode signal processing, which is steadily more common than voltage-style signal processing, because it operates in current mode on all terminals. The suggested component was implemented using Finfet technology, and its performances were assessed using simulations using cadence tools and linear technology SPICE. They demonstrate the new active element's usage, with a maximum bandwidth of 300MHz. The highest power consumption is 1.01 mW, and the supply voltages can be as low as ±0.1 V. The low-power consumption and wide current range tuning of the suggested Zc-CDTA are achieved.

1 V Electronically Tunable Differential Difference Current Conveyors Using Multiple-Input Operational Transconductance Amplifiers.

This paper presents electronically tunable current conveyors using low-voltage, low-power, multiple-input operational transconductance amplifiers (MI-OTAs). The MI-OTA is realized using the multiple-input bulk-driven Metal Oxide Semiconductor transistor (MIBD-MOST) technique to achieve minimum power consumption. The MI-OTA also features high linearity, a wide input range, and a simple Complementary Metal Oxide Semiconductor (CMOS). Thus, high-performance electronically tunable current conveyors are obtained. With the MI-OTA-based current conveyor, both an electronically tunable differential difference current conveyor (EDDCC) and a second-generation electronically tunable current conveyor (ECCII) are available. Unlike the conventional differential difference current conveyor (DDCC) and second-generation current conveyor (CCII), the current gains of the EDDCC and ECCII can be controlled by adjusting the transconductance ratio of the current conveyors. The proposed EDDCC has been used to realize a voltage-to-current converter and current-mode universal filter to show the advantages of the current gain of the EDDCC. The proposed current conveyors and their applications are designed and simulated in the Cadence environment using 0.18 μm TSMC (Taiwan Semiconductor Manufacturing Company) CMOS technology. The proposed circuit uses ±0.5 V of power supply and consumes 90 μW of power. The simulation results are presented and confirm the functionality of the proposed circuit and the filter application. Furthermore, the experimental measurement of the EDDCC implemented in the form of a breadboard connection using a commercially available LM13700 device is presented.

Electronically Tunable Differential Difference Current Conveyor Using Commercially Available OTAS

This paper presents a new electronically tunable differential difference current conveyor (EDDCC) using the commercially available operational transconductance amplifiers (OTAs). Unlike the conventional DDCC, the proposed EDDCC offers current gain that can be electronically controlled. The EDDCC can be used to realize a new electronically tunable fully differential difference second-generation current conveyor (EFDCCII). Therefore, the current gain of the proposed EFDCCII can be electronically controlled. To show the advantages of the proposed EDDCC and EFDCCII, the EDDCC has been used to realize a quadrature oscillator and the EFDCCII has been used to realize a current-mode universal filter. The proposed circuits have been investigated by simulation and experimental tests using the commercially available LM13700 OTAs.

CMOS Compatible First-Order Current Mode Universal Filter Structure and its Possible Tunable Variant

A novel first-order universal filter structure supporting current mode operation is proposed in this paper. The filter has a single active building block based realization and utilizes an extra-X second-generation current conveyor as an active building block. Additionally, the proposed circuit employs a grounded resistor and a grounded capacitor as passive components. The circuit has the ability to deliver the all-pass, high-pass, and low-pass functionalities simultaneously without meeting any passive components matching constraint. High output impedance and load insensitive outputs are other remarkable signal processing features offered by the proposed filter structure. Theoretical behavior of the proposed filter is described by presenting ideal, non-ideal, parasitic, and stability analyses. Additionally, the resistorless variant of the proposed filter is also shown to impart the tunability feature. Personal simulation program with integrated circuit emphasis (PSPICE) simulation results are presented to verify the theoretically described performance of the proposed universal filter. Complementary metal oxide semiconductor (CMOS) realization of extra-X second-generation current conveyor is utilized for the purpose of simulations, therefore, the filter is CMOS compatible.

A Current Mode Universal Filter and a Single Resistance Controlled Oscillator Employing only Grounded Passive Elements: Applications of VDCC

This research article explores the possible applications of voltage differencing current conveyor (VDCC), as a current mode universal filter and a sinusoidal oscillator. Without the need for an additional active/passive element, a very simple hardware modification makes it a dual-mode quadrature oscillator from the filter configuration. Both the proposed circuit requires only two VDCC and all grounded passive elements, hence a preferable choice for integration. The filter has some desirable features such as availability of all five explicit outputs, independent tunability of filter parameters. Availability of explicit quadrature current outputs, independence in start and frequency of oscillations, makes it a better oscillator design. Apart from prevalent CMOS simulation results, VDCC is also realized and experimentally tested using the off-the-shelf integrated circuit. All the pen and paper analysis such as non-ideal, sensitivity and parasitic analysis supports the design.

An Explicit Output Current-mode Quadrature Sinusoidal Oscillator and a Universal Filter Employing Only Grounded Passive Components - a Minimal Realisation

The use of voltage differencing current conveyor as an active device to design a current-mode oscillator along with a universal filter with only grounded passive elements is the main focus of this manuscript. This re-arranging circuit can work as a sinusoidal oscillator as well as a current-mode universal filter, by simple selection of passive switches. Both the circuits employ only two active devices and three grounded passive elements. The designed oscillator provides two distinctive current outputs with a quadrature-phase difference. It also maintains an independent condition of oscillation and frequency of oscillation. Moreover, the basic responses including low pass, high pass, and band pass are easily available from a current-mode universal filter. The low input impedance and high output impedance are amongst the noteworthy features of the current-mode derived filter. Non-ideal, parasitic, and sensitivity analysis of the designed circuits are also incorporated in the manuscript. Cadence PSPICE software simulation results are also included to justify the design idea. Experimental implementation of the described circuit has also been shown by employing special-purpose amplifier integrated circuit, i.e., OPA860.

A new first-order universal filter consisting of two ICCII + s and a grounded capacitor

In this paper, a new inverting second-generation current conveyor-based first-order current-mode universal filter is proposed. The main features of the proposed filter are described as follows: the use of a grounded capacitor that is attractive for integration, electronically tunable, no passive element matching condition, resistor-less, having the feature of both low input and high output impedances as well as providing all the first-order universal filter responses such as low-pass, high-pass and all-pass ones. As application examples, a sinusoidal oscillator and a four-phase oscillator are given. Many simulations through SPICE program and some experiments are achieved in order to exhibit the performance of the proposed filter.

Various applications of analog signal processing employing voltage differencing current conveyor and only grounded passive elements: a re-convertible approach

A re-convertible circuit that can either act as a current-mode universal filter or as a fully un-coupled dual-mode single-resistance-controlled quadrature oscillator or simply works as a grounded loss-less inductor, by simple selection of appropriate passive switches, is proposed here. The proposed circuit requires a maximum of two voltage differencing current conveyors as an active element in the case of filter and oscillator application, whereas only one active device suffices the purpose of active inductor implementation. In all the cases only grounded passive elements are employed. Various regular analysis for the proposed circuits have also been included here to support the theoretical idea. The workability of these circuits has been demonstrated by practicing PSPICE simulation software with TSMC CMOS 0.18 μm process parameters along with the experimental justification of the derived application using commercially available integrated circuits.

Electronically tunable DV-EXCCCII-based universal filter

ABSTRACT A new analog block, Differential Voltage Extra-X Current Controlled Conveyor (DV-EXCCCII) based current mode universal filter configuration is introduced in this paper. Only one current mode analog block DV-EXCCCII, three grounded components are used to design proposed filter configuration. This circuit provides high output impedance, which allows cascading feature to circuit without need of extra buffer circuit. This configuration realise all five (Low Pass, High Pass, All Pass, Band Pass and Band Reject) second-order filter functions with an appropriate selection of input. Bias current of DV-EXCCCII provides the electronic tuning characteristic to proposed circuit. Sensitivity due to passive components and non-idealities of the analog block is low and magnitude is below unity. The proposed filter circuit configuration is designed in CADENCE and simulated with SPECTRE using 180 nm UMC CMOS process technology.

Resistorless Realization of First‐Order Current Mode Universal Filter

AbstractThis paper proposes a first‐order current mode universal filter employing single active building block, namely differential difference dual‐X second generation current conveyor. The proposed filter is designed to provide multiple filter responses simultaneously, namely low‐pass, high‐pass, and all‐pass on applying a current signal at its input terminal. The proposed work also enjoys the presence of metal oxide semiconductor transistors working as tunable resistors. Some of the key features of the proposed filter are as follows: use of single passive element (a grounded capacitor), ease of cascadability as all the outputs are available at highimpedance ports, low active and passive sensitivities, significantly high frequency of operation (3 MHz), low total harmonic distortion of output current (1.28%), low output current noise (10 pA/√Hz), and low power dissipation (2 mW). A detailed study of device nonidealities is also presented to show the satisfactory performance of the proposed structure under all practical considerations. PSPICE simulations effectively demonstrate the good performance of the proposed filter.

Fully Integrable/Cascadable CM Universal Filter and CM Quadrature Oscillator Using VDCC and Only Grounded Passive Elements

This paper proposes a current mode universal filter circuit, employing two active elements along with four grounded passive components only. The derived circuit realizes all five filtering responses, i.e., low pass (LP), band pass (BP), high pass (HP), band reject (BR) and all pass (AP), simultaneously from high-impedance ports along with the input being fed to low-impedance port, thus making it a fully cascadable filter. In addition, the designed circuit exhibits independent tunability of its quality factor. With the idea of making the proposed filter fully integrable, a resistor-less approach of the configuration has also been discussed. By making slight modifications in the filter configuration, a current mode single-resistance-controlled quadrature oscillator circuit has also been derived. The ideal, nonideal, sensitivity and parasitic analysis have been conducted for the designed configurations. The functionality of the proposed structures is verified by PSPICE simulations using 0.18[Formula: see text][Formula: see text]m CMOS technology. The designs have also been verified using PSPICE macro-model of the commercially available IC, i.e., OPA860.

Novel current mode universal filter and dual-mode quadrature oscillator using VDCC and all grounded passive elements

ABSTRACTThe paper introduces a universal filter operating in current mode and a quadrature oscillator operating in current and voltage mode, employing Voltage Differencing Current Conveyor as active device along with all grounded passive elements. Apart from providing all five filter responses, i.e. low pass, high pass, band pass, band reject and all pass, the filter configuration also supports independent tunability of quality factor. The oscillator configuration can be easily realised with slight modifications in filter circuit, and features like low component count, use of grounded capacitors for supporting efficient integrated circuit implementation and availability of explicit current outputs are witnessed in both the devised networks. In the oscillator, network’s condition and frequency of oscillation can be independently tuned. For practical validation of the proposed network, PSPICE simulation software is used. The simulation results include two sets of outputs, one using CMOS (Complmentary Metal Oxide Semiconductor) implementation of Voltage Differencing Current Conveyor (VDCC) and another using off the shelf IC (Integrated Circuit) implementation of VDCC.

One-Input Three-Output Current-Mode Universal Filter Using Translinear Current Conveyors

This paper presents a new current-mode universal filter with one-input three-output employing three translinear current conveyors and two grounded capacitors. The proposed filter provides low-pass, band-pass, high-pass current response with high output impedance output which can be directly connected for current-mode circuit. The band-pass and all-pass filters can also be obtained. The parameters wo and Q can be controlled separately and electronically by the bias currents of current conveyors. For realizing all filtering functions, no passive and active matching conditions are required. The active and passive sensitivities are low. The characteristic of the proposed circuit can be confirmed by SPICE simulations.

Realization of Current Mode Universal Filter and a Dual-Mode Single Resistance Controlled Quadrature Oscillator Employing VDCC and Only Grounded Passive Elements

The manuscript presents a circuit that can act as a universal filter as well as a single resistence controlled oscillator by unpretentiously changing the switch positions. The circuit employs only two active devices and all grounded passive elements. The utilization of only grounded passive components makes this circuit a better choice for integrated circuit implementation. The current mode biquadratic filter offers all the five basic responses along with independent tunability of its quality factor. The dual-mode quadrature sinusoidal oscillator offers explicit current outputs along with voltage outputs. The circuit also offers a simple and uncoupled condition of oscillation and frequency of oscillation. The typical analysis such as non-ideal, sensitivity and parasitic analysis along with the regular simulation results as well as experimental results are exposed here, to strengthen the design idea.

Grounded capacitor based fully cascadable electronically tunable current-mode universal filter

A novel current-mode (CM) universal filter configuration composed of five plus-type second-generation current conveyors (CCII+s) as active components besides three resistors and three grounded capacitors as passive elements is proposed in this paper. The proposed filter can simultaneously provide high-pass, band-pass and low-pass responses. Also, it can realize all-pass and notch responses with interconnection of convenient output currents. It can be cascaded with other CM ones easily because it has low input and high output impedances. It offers orthogonal control of angular resonance frequency and quality factor. An electronically tunable universal filter can be easily obtained if plus-type current controlled current conveyors are replaced instead of each of the five CCII+s and all the three resistors are removed. Nevertheless, it needs a single passive element matching constraint for notch and all-pass filter responses. Some simulation and experimental test results are included to confirm the theory.

A New DVCC+ Based Second-Order Current-Mode Universal Filter Consisting of Only Grounded Capacitors

In this paper, a new second-order current-mode universal filter using only two plus-type differential voltage current conveyors, three resistors and two grounded capacitors is proposed. The proposed circuit with two identical inputs and three outputs can simultaneously provide second-order high output impedance low-pass, band-pass and notch filter responses. Also, it can realize high-pass and all-pass filter responses with interconnection of relevant output currents. It can be easily tuned electronically. It can be operated properly at high frequencies. A number of simulations based on SPICE program and an experimental test are achieved in order to demonstrate the performance of the proposed filter.

Fully‐balanced four‐terminal floating nullor for ultra‐low voltage analogue filter design

This study presents a new complementary metal–oxide–semiconductor (CMOS) structure for a fully balanced four-terminal floating nullor (FBFTFN) which is suitable for ultra-low-voltage and low-power applications. This structure employs a bulk-driven quasi-floating-gate (BD-QFG) metal–oxide–semiconductor transistor technique to provide the capability of ultra-low-voltage, low-power operations as well as extended input voltage range. The functionality of the proposed circuits is demonstrated through simulations using SPICE and TSMC 0.18 µm n-well CMOS technology with supply voltage of 0.5 V and dissipation power of 9.4 µW. To confirm the attractive features of the proposed circuit, the fully balanced filters such as band-pass Sallen–Key filter, voltage-mode universal biquadratic filter and current-mode sixth-order low-pass filter using proposed BD-QFG FBFTFN as active elements have been designed.

Two lossy integrator loop based current-mode electronically tunable universal filter employing only grounded capacitors

In this paper, a novel single-input and multiple-output second-order current-mode universal filter is proposed where lossy integrator blocks, scaling blocks and summing blocks are employed. The proposed filter can simultaneously generate all the five universal filter responses namely; low-pass, high-pass, band-pass, notch and all-pass responses without requiring any critical passive component matching conditions. It uses only two grounded capacitors as passive components and BJTs as active elements; thus, it can be classified as an active-C filter. Both resonance frequency and quality factor of the proposed filter can be tuned electronically. Approximately 1.5 decades adjustable input frequency range for all the universal filter responses and high quality factor for band-pass response are obtained. Obtained PSpice simulation results confirm the theoretical design. Non-ideality and Monte Carlo analyses are also given. A practical realization of the single lossy integrator is accomplished. All the presented results are discussed.

A wideband linear tunable CDTA and its application in field programmable analogue array

In this paper, a NMOS-based wideband low power and linear tunable transconductance current differencing transconductance amplifier (CDTA) is presented. Based on the NMOS CDTA, a novel simple and easily reconfigurable configurable analogue block (CAB) is designed. Moreover, using the novel CAB, a simple and versatile butterfly-shaped FPAA structure is introduced. The FPAA consists of six identical CABs, and it could realize six order current-mode low pass filter, second order current-mode universal filter, current-mode quadrature oscillator, current-mode multi-phase oscillator and current-mode multiplier for analog signal processing. The Cadence IC Design Tools 5.1.41 post-layout simulation and measurement results are included to confirm the theory.