Current feedback operational amplifier based two-port frequency equalizer

Integer-and Fractional-Order Integral and Derivative Two-Port Summations: Practical Design Considerations

“…No [5] integrator No CMOS OTAs active Medium Yes <1 kHz N/A - [6] both No CFOAs active Medium Yes <100 kHz N/A - [7] both [10] integrator No OAs passive Low Yes <10 kHz I controller - [11] both No OAs passive Low Yes <100 Hz PID No [12] both N/A FPAA (OAs) active High No <100 Hz PID No [13] both [18] both No CMOS OAs active High Yes <1 kHz PI controller No [19] integrator No CMOS OTAs active High Yes <10 MHz N/A - [20] both No CFOAs active Medium Yes <100 kHz N/A - [21] integrator No OTAs active Medium Yes <100 kHz N/A - D. Mondal et al [2] brought a solution of the lossless integrator using a fractional-order passive element (FOE), known also as constant phase element (CPE) as a part of feedback loop of operational amplifier (OA) followed by inverter. However, adjustability and other features (two different slopes in magnitude frequency responses, various starting and final phase shifts in observed bandwidth, etc.)…”

“…So-called bilinear synthesis brought significant contributions to the adjustability of the features of fractional-order devices [8,[18][19][20][21]. Electronic tuning of zero and pole frequencies allows one to form an almost arbitrary frequency response with very simple and immediate reconfiguration [8,[19][20][21].…”

“…(a) Many proposed circuitries (except FPAA, FPGA-based) have quite complex topology, with many active and/or passive elements [9,12,[16][17][18][19], especially circuits with fractional-order behavior and approximations by higher-order filters [3,5,6,13] or chain of bilinear segments [8,9,14,15,[18][19][20][21], (b) some concepts require software programming [12,16,17], (c) tested operational bandwidth is quite narrow in many cases [3][4][5]7,8,[11][12][13]18], (d) summing of fractional-order as well as integer-order two ports was not analyzed deeply in the past, (e) single-parameter electronic adjustment of the time constant of the resulting response of two-port summing was not studied in the past, except R. Sotner et al [9], but the overall circuit topology is based upon a chain of bilinear sections, and therefore, it is not one of the simplest solutions…”

“…Frequency responses influenced by the fractional-order behavior of used components are studied more frequently in recent years [1]. Many works in this field focus on novel solutions of integral and derivative two-ports (for example [2][3][4][5][6][7][8][9]), proportional integral and derivative controllers (for example [10][11][12][13][14][15][16][17][18] and so-called bilinear two ports [8,9,[19][20][21] serving for various purposes. Two ports, known as integrators and differentiators, have started to be interesting for designers of fractional-order systems, and especially for proportional, integral and derivative controllers (PIDs).…”

0.5 V bulk ‐ driven CMOS fully differential current feedback operational amplifier

“…There are many CFOA-based analogue circuits available in open literature; see, e.g. [1][2][3][4][5][6][7][8][9][10][11][12]. In [1], many analogue circuits using CFOA as active element are described, including inductor and impedance simulators, active filters, oscillators and non-linear circuits.…”