Realization of Low-Voltage Modified CBTA and Design of Cascadable Current-Mode All-Pass Filter

In this paper, a low voltage modified current backward transconductance amplifier (MCBTA) and a novel first-order current-mode (CM) all-pass filter are presented. The MCBTA can operate with ±0.9 V supply voltage and the total power consumption of MCBTA is 1.27 mW. The presented all-pass filter employs single MCBTA, a grounded resistor and a grounded capacitor. The circuit possesses low input and high output impedances which make it ideal for current-mode systems. The presented all-pass filter circuit can be made electronically tunable due to the bias current of the MCBTA. Non-ideal study along with simulation results are given for validation purpose. Further, an nth-order cascadable all-pass filter is also presented. It uses n MCBTAs, n grounded resistors and n grounded capacitors. The performance of the proposed circuits is demonstrated by using PSPICE simulations based on the 0.18 µm TSMC level-7 CMOS technology parameters

Supplementary First-Order All-Pass Filters with Two Grounded Passive Elements Using FDCCII

In this study, two novel first-order all-pass filters are proposed using only one grounded resistor and one grounded capacitor along with a fully differential current conveyor (FDCCII). There is no element-matching restriction. The presented all-pass filter circuits can be made electronically tunable due to the electronic resistors. Furthermore, the presented circuits enjoy high-input impedance for easy cascadability. The theoretical results are verified with SPICE simulations

Low-Voltage High-Linearity Wideband Current Differencing Transconductance Amplifier and Its Application on Current-Mode Active Filter

A low-voltage high-linearity wideband current differencing transconductance amplifier (CDTA) is presented in this paper. The CDTA consists of a current differencing circuit and a cross-coupling transconductance circuit. The PSPICE simulations of the proposed CDTA show a good performance: -3dB frequency bandwith is about 900 MHz, low power consumption is 2.48 mW, input current linear range is ±100 µA and low current-input resistance is less than 20 Ω, high current-output resistance is more than 3 MΩ. PSpice simulations for a current-mode universal filter and a proposed high-order filter are also conducted, and the results verify the validity of the proposed CDTA

A Low-Voltage Electronically Tunable MOSFET-C Voltage-Mode First-Order All-Pass Filter Design

This paper presents a simple electronically tunable voltage-mode first-order all-pass filter realization with MOSFET-C technique. In comparison to the classical MOSFET-C filter circuits that employ active elements including large number of transistors the proposed circuit is only composed of a single two n-channel MOSFET-based inverting voltage buffer, three passive components, and one NMOS-based voltage-controlled resistor, which is with advantage used to electronically control the pole frequency of the filter in range 103 kHz to 18.3 MHz. The proposed filter is also very suitable for low-voltage operation, since between its supply rails it uses only two MOSFETs. In the paper the effect of load is investigated. In addition, in order to suppress the effect of non-zero output resistance of the inverting voltage buffer, two compensation techniques are also introduced. The theoretical results are verified by SPICE simulations using PTM 90 nm level-7 CMOS process BSIM3v3 parameters, where +/- 0.45 V supply voltages are used. Moreover, the behavior of the proposed filter was also experimentally measured using readily available array transistors CD4007UB by Texas Instruments

Current Conveyor All-Pass Sections: Brief Review and Novel Solution

This study relates to the review of an important analog electronic function in form of all-pass filter’s realization using assorted current conveyor types and their relative performances, which resulted in a novel solution based on a new proposed active element. The study encompasses notable proposals during last the decade or more, and provides a platform for a broader future survey on the topic for enhancing the knowledge penetration amongst the researchers in the specified field. A new active element named EXCCII (Extra-X second generation current conveyor) with buffered output is found in the study along with its use in a new first-order all-pass section, with possible realization using commercially available IC (AD-844) and results

Design and practice of simple first-order all-pass filters using commercially available IC and their applications

First-order all-pass filter circuits, both non-inverting and inverting, could be the focus of this article, which could include the design and implementation of first-order all-pass filter circuits. Using a standard integrated circuit (IC): AD830, as well as a single resistor and a single capacitor, the proposed first-order all-pass filters could well be built. The AD830 is an integrated circuit (IC) manufactured by Analog Devices Corporation that is available for purchase. The pole frequency and phase response of the proposed all-pass filters could well be directly modified by attuning the resistor in the circuit. Aside from that, the output voltage has a low impedance, making it appropriate for use in voltage-mode circuits. In addition, the proposed first-order all-pass filter is used to design the multiphase sinusoidal oscillator, which serves as an example of an application wherein the oscillation condition can be adjusted without impacting the frequency. The gain and phase responses of the proposed all-pass filters, as well as their phase response adjustment, time-domain response, and total harmonic distortion of signals, are all shown via computer simulation using the PSPICE software, as well as their experimental results. For the proposed circuits, a statistical analysis is coupled with a Monte Carlo simulation to estimate the performance of the circuits. In accordance with the results of this study, a theoretical design suitable for developing a worksheet for teaching and learning in electrical and electronic engineering laboratories has already been develope

Voltage-Mode All-Pass Filters Using Universal Voltage Conveyor and MOSFET-Based Electronic Resistors

The paper presents two novel realizations of voltage-mode first-order all-pass filters. Both circuits use single universal voltage conveyor (UVC), single capacitor, and two grounded resistors. Using the two NMOS transistors-based realizations of the electronic resistor with two symmetrical power supplies, presented all-pass filter circuits can be easily made electronically tunable. Proposed filter structures provide both inverting and non-inverting outputs at the same configuration simultaneously and they have high-input and low-output impedances that are desired for easy cascading in voltage-mode operations. The nonidealities of the proposed circuits are also analyzed and compared. The theoretical results of both circuits are verified by SPICE simulations using TSMC 0.35 μm CMOS process parameters. Based on the evaluation, the behavior of one of the circuits featuring better performance was also experimentally measured using the UVC-N1C 0520 integrated circuit

New families of voltage-mode and current-mode filter circuits.

In some previous papers, feed forward configurations of realizing second order all pass transfer functions with complex poles by adding some configurations to a first order circuit are discussed. In this dissertation, the above idea extended to realize some other basic second order complex pole filter transfer functions. A new corollary for circuit conversion is proposed and proved. This corollary is useful for converting op amp based voltage-mode circuits to their CCII based equivalent circuits, as are other existing theorems. But the new corollary is useful for converting circuits that cannot be converted by other theorems

Cascadable Current-Mode First-Order All-Pass Filter Based on Minimal Components

A novel current-mode first-order all-pass filter with low input and high output impedance feature is presented. The circuit realization employs a single dual-X-second-generation current conveyor, one grounded capacitor, and one grounded resistor, which is a minimum component realization. The theoretical results are verified using PSPICE simulation program with TSMC 0.35 μm CMOS process parameters