<abstract xmlns="http://www.w3.org/1999/xhtml"><p>Presented research introduces active filtering circuits which allow change of the transfer type without necessity of reconnection of the input or output terminal that can be very useful for on-chip applications. Our attention is focused on simple first-order filters that allow high-pass response (HP), all-pass response (AP) and also direct transfer (DT) with constant magnitude and phase characteristics between two terminals (input and output) by adjusting of one controllable parameter (current gain <italic>B</italic> in our case). Useful modification of the well-known current follower transconductance amplifier (CFTA), the so-called Z-copy current-controlled current follower differential input transconductance amplifier (ZC-CCCFDITA) and adjustable current amplifier were utilized in these circuits. Interesting possibilities (crossing between several transfer functions) of presented circuits require different values of <italic>B</italic> to obtain desired transfer function that is very important for practice and selection of specific way of control. Requirements on value of this continuously controllable gain <italic>B</italic> differ among presented structures. Theory is supported by simulation and measurement results with behavioral models utilizing commercially available active elements and simulation results with active elements based on CMOS models.</p></abstract>

Presented research introduces active filtering circuits which allow change of the transfer type without necessity of reconnection of the input or output terminal that can be very useful for on-chip applications. Our attention is focused on simple first-order filters that allow high-pass response (HP), all-pass response (AP) and also direct transfer (DT) with constant magnitude and phase characteristics between two terminals (input and output) by adjusting of one controllable parameter (current gain B in our case). Useful modification of the well-known current follower transconductance amplifier (CFTA), the so-called Z-copy current-controlled current follower differential input transconductance amplifier (ZC-CCCFDITA) and adjustable current amplifier were utilized in these circuits. Interesting possibilities (crossing between several transfer functions) of presented circuits require different values of B to obtain desired transfer function that is very important for practice and selection of specific way of control. Requirements on value of this continuously controllable gain B differ among presented structures. Theory is supported by simulation and measurement results with behavioral models utilizing commercially available active elements and simulation results with active elements based on CMOS models.

First–Order Transfer Sections with Reconnection–Less Electronically Reconfigurable High–Pass, All–Pass and Direct Transfer Character

Department of Radio Electronics, Faculty of Electrical Engineering and Communication, Brno University of Technology, Technicka 3082/12, 616 00 Brno, Czech Republic

Department of Telecommunications, Faculty of Electrical Engineering and Communication, Brno University of Technology, Technicka 3082/12, 616 00 Brno, Czech Republic

Department of Microelectronics, Faculty of Electrical Engineering and Communication, Brno University of Technology, Technicka 3058/10, 616 00 Brno, Czech Republic

D3-Friends Apartments, IP Extension, Delhi, India

Department of Technical Studies, College of Polytechnics, Jihlava, Tolsteho, 16, 586 01, Jihlava, Czech republic

Journal of Electrical Engineering

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Presented research introduces active filtering circuits which allow change of the transfer type without necessity of reconnection of the input or output...

First–Order Transfer Sections with Reconnection–Less Electronically Reconfigurable High–Pass, All–Pass and Direct Transfer Character

Published Online: Mar 17, 2016

Page range: 12 - 20

Received: Dec 28, 2014

DOI: https://doi.org/10.1515/jee-2016-0002

Keywords
active filters, electronic control, reconfiguration, reconnection-less multifunction, Z-copy current-controlled current follower differential input transconductance amplifier, ZC-CCCFDITA

© 2016 Faculty of Electrical Engineering and Information Technology, Slovak University of Technology

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

First–Order Transfer Sections with Reconnection–Less Electronically Reconfigurable High–Pass, All–Pass and Direct Transfer Character

Published Online: Mar 17, 2016

Page range: 12 - 20

Received: Dec 28, 2014

DOI: https://doi.org/10.1515/jee-2016-0002

Keywordsactive filters, electronic control, reconfiguration, reconnection-less multifunction, Z-copy current-controlled current follower differential input transconductance amplifier, ZC-CCCFDITA

© 2016 Faculty of Electrical Engineering and Information Technology, Slovak University of Technology

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Keywords
active filters, electronic control, reconfiguration, reconnection-less multifunction, Z-copy current-controlled current follower differential input transconductance amplifier, ZC-CCCFDITA