Norbert Herencsar

Publications

• An electronically tunable current-mode quadrature oscillator using PCAs

  N. Herencsar, A. Lahiri, K. Vrba, J. Koton

  International Journal of Electronics. 01/2012;

  The paper presents a new realization of active RC sinusoidal oscillator with electronically tunable condition and frequency of oscillation. As compared to the class of three resistors, two capacitors (3R-2C) based canonic oscillators, the proposed circuit here uses only two resistors and two capacit... [more] The paper presents a new realization of active RC sinusoidal oscillator with electronically tunable condition and frequency of oscillation. As compared to the class of three resistors, two capacitors (3R-2C) based canonic oscillators, the proposed circuit here uses only two resistors and two capacitors as the passive components and still provides non-interactive tuning laws for the condition of oscillation (CO) and the frequency of oscillation (FO). The proposed circuit employs new bipolar programmable current amplifier (PCA) as the active building block and is capable of simultaneously providing two explicit quadrature current outputs. SPICE simulation results have been included to verify the workability of the circuit as an oscillator and the tuning range of the FO.

• Novel floating FDNR, inductor and capacitor simulator using CBTA

  Umut E. Ayten, Mehmet Sagbas, Norbert Herencsar, Jaroslav Koton

  Proceedings of the 2011 34th International Conference on Telecommunications and Signal Processing (TSP),, Budapest, Hungary; 01/2011

  In this study novel floating frequency dependent negative resistor (FDNR), floating inductor (FI), floating capacitor and floating resistor simulator circuit employing two CBTAs and three passive components is proposed. The presented circuit can realize floating FDNR, inductor, capacitor or resistor... [more] In this study novel floating frequency dependent negative resistor (FDNR), floating inductor (FI), floating capacitor and floating resistor simulator circuit employing two CBTAs and three passive components is proposed. The presented circuit can realize floating FDNR, inductor, capacitor or resistor depending on the passive component selection. Since the passive elements are all grounded, this circuit is suitable for fully integrated circuit design. The circuit does not require any component matching conditions, and it has a good sensitivity performance with respect to tracking errors. Moreover, the proposed FDNR, inductance, capacitor and resistor simulator can be tuned electronically by changing the biasing current of the CBTA or can be controlled through the grounded resistor or capacitor. The proposed floating FDNR simulator circuit is demonstrated by using a PSPICE simulation for 0.25 μm TSMC CMOS technology.

• A new compact CMOS realization of sinusoidal oscillator using a single modified CBTA,

  Norbert Herencsar, Jaroslav Koton, Kamil Vrba, Abhirup Lahiri, Umut E. Ayten, Mehmet Sagbas

  Proceedings of the 21st International Conference Radioelektronika 2011,, Brno, Czech Republic; 01/2011

  In this paper, a new compact realization of sinusoidal oscillator using modified current backward transconductance amplifier (MCBTA) is reported. The proposed circuit employs a single MCBTA and four passive components including two grounded capacitors. The circuit provides completely de-coupled cond... [more] In this paper, a new compact realization of sinusoidal oscillator using modified current backward transconductance amplifier (MCBTA) is reported. The proposed circuit employs a single MCBTA and four passive components including two grounded capacitors. The circuit provides completely de-coupled condition of oscillation (CO) of the frequency of oscillation (FO), i.e. no term in the CO is present in the FO and vice versa. Both the CO and FO are independently tunable by two different grounded resistors. The FO is also tunable by means of the transconductance and thereby is electronically tunable. SPICE simulation results have confirmed the workability of the proposed circuit.
• 0.31

  Impact points

  Current-mode dual-phase precision full-wave rectifier using current-mode two-cell winner-takes-all (WTA) circuit

  J. Koton, A. Lahiri, N. Herencsar, K. Vrba

  Radioengineering. 01/2011; 20:428-432.

  In addition to the recently proposed full-wave rectifier by Prommee et al. [25] using voltage-mode (VM) two-cell winner-takes-all (WTA) circuit, we present currentmode (CM) precision full-wave rectifier using CM two-cell WTA circuit. The popular Lazzaro’s CM WTA circuit has been employed for the pur... [more] In addition to the recently proposed full-wave rectifier by Prommee et al. [25] using voltage-mode (VM) two-cell winner-takes-all (WTA) circuit, we present currentmode (CM) precision full-wave rectifier using CM two-cell WTA circuit. The popular Lazzaro’s CM WTA circuit has been employed for the purpose and there is no requirement of inverting the input signal as in [25]. Also, dual complimentary phases of the output current signal are available from high-output impedance terminals for explicit utilization. As compared to many recently proposed CM rectifiers using complex active devices, e.g. dual-X current conveyor or universal voltage conveyor, our circuit is very compact and requires a total of 21 transistors. SPICE simulation results of the circuit implemented using 0.35 μm TSMC CMOS technology are provided which verify the workability of the proposed circuit.

• KHN-equivalent voltage-mode filters using universal voltage conveyors,

  Jaroslav Koton, Norbert Herencsar, Kamil Vrba

  AEU - International Journal of Electronics and Communications,. 01/2011; 65(2):pp. 154-160..

  The analog circuit design is very often focused on the design of frequency filters employing different types of active elements. In this paper we present the universal voltage conveyor that is used for the design of the KHN-equivalent filters working in the voltage-mode. Auxiliary voltage inputs of ... [more] The analog circuit design is very often focused on the design of frequency filters employing different types of active elements. In this paper we present the universal voltage conveyor that is used for the design of the KHN-equivalent filters working in the voltage-mode. Auxiliary voltage inputs of the active elements are used to reduce the number of floating admittances in the structure. Both proposed structures are easily cascadable since the input and output impedances are in theory infinitely high and zero, respectively. The behavior of the filters has been verified through PSpice simulations and furthermore by experimental measurements.

• Voltage-mode all-pass filters using universal voltage conveyor and MOSFET-based electronic resistors,

  Norbert Herencsar, Jaroslav Koton, Jan Jerabek, Kamil Vrba, Oguzhan Cicekoglu

  Radioengineering,. 01/2011; 20(1):pp. 10-18..

  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 sup... [more] 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.

• Current and Voltage Conveyors in Current- and Voltage-Mode Precision Full-Wave Rectifiers,

  Jaroslav Koton, Norbert Herencsar, Kamil Vrba

  Radioengineering,. 01/2011; 20(1):pp. 19-24..

  In this paper new versatile precision full-wave rectifiers using current and/or voltage conveyors as active elements and two diodes are presented. The performance of these circuit solutions is analysed and compared to the opamp based precision rectifier. To analyze the behavior of the functional blo... [more] In this paper new versatile precision full-wave rectifiers using current and/or voltage conveyors as active elements and two diodes are presented. The performance of these circuit solutions is analysed and compared to the opamp based precision rectifier. To analyze the behavior of the functional blocks, the frequency dependent RMS error and DC transient value are evaluated for different values of input voltage amplitudes. Furthermore, experimental results are given that show the feasibilities of the conveyor based rectifiers superior to the corresponding operational amplifier based topology.

• Resistorless cascadable voltage-mode all-pass filter,

  Bilgin Metin, Norbert Herencsar, Oguzhan Cicekoglu

  Proceedings of the International Conference on Applied Electronics - APPEL 2011,, Pilsen, Czech Republic, accepted; 01/2011

  In this study, a tunable voltage-mode (VM) all-pass filter is presented using controlled current conveyors. Firstly, the circuit has high-input impedance for easy cascadability. Secondly, it employs a grounded capacitor. Finally, it provides electronic tunability. The theoretical results are verifie... [more] In this study, a tunable voltage-mode (VM) all-pass filter is presented using controlled current conveyors. Firstly, the circuit has high-input impedance for easy cascadability. Secondly, it employs a grounded capacitor. Finally, it provides electronic tunability. The theoretical results are verified with SPICE simulations.

• Electronically tunable MOSFET-C voltage-mode all-pass filter based on universal voltage conveyor,

  Norbert Herencsar, Jaroslav Koton, Kamil Vrba, Shahram Minaei

  Proceedings of the International Conference on Computer and Communication Device - ICCCD 2011,, Bali Island, Indonesia; 01/2011

  In this paper, a new voltage-mode first-order all-pass filter with high-input and low-output impedances is presented. The circuit is composed of single universal voltage conveyor (UVC), single capacitor, and an n-channel MOSFET-based voltage-controlled resistor (VCR) that allows to control the pole ... [more] In this paper, a new voltage-mode first-order all-pass filter with high-input and low-output impedances is presented. The circuit is composed of single universal voltage conveyor (UVC), single capacitor, and an n-channel MOSFET-based voltage-controlled resistor (VCR) that allows to control the pole frequency ω0 of the filter electronically. No component-matching constraints are required and it has low sensitivity. The proposed filter provides both of inverting and non-inverting outputs at the same configuration simultaneously. The non-idealities of the proposed circuit are also analyzed. The theoretical results are verified by SPICE simulations using TSMC 0.35 um CMOS process parameters.

• Precision full-wave current-mode rectifier using current differencing transconductance amplifier,

  Jaroslav Koton, Norbert Herencsar, Kamil Vrba, Shahram Minaei

  Proceedings of the International Conference on Computer and Communication Device - ICCCD 2011,, Bali Island, Indonesia; 01/2011

  In this paper new high performance current-mode precision full-wave rectifier using the current differencing transconductance amplifier (CDTA) is presented. To analyze the behavior of the proposed rectifier, the frequencydependent RMS error and DC transient value are evaluated for different values o... [more] In this paper new high performance current-mode precision full-wave rectifier using the current differencing transconductance amplifier (CDTA) is presented. To analyze the behavior of the proposed rectifier, the frequencydependent RMS error and DC transient value are evaluated for different values of input current amplitudes. The SPICE simulations are also included that show the feasibility to rectify signals of frequency 10 MHz and beyond with no or minimal distortion.

• Current Follower Transconductance Amplifier (CFTA) - A Useful Building Block for Analog Signal Processing,

  Norbert Herencsar, Jaroslav Koton, Kamil Vrba, Ivo Lattenberg

  Journal of Active and Passive Electronic Devices,. 01/2011; 6(3-4):pp. 217-229..

  In this paper a new active element for the realization of current-mode analog blocks Current Follower Transconductance Amplifier (CFTA) is presented. The element is a combination of the Current Follower (CF) and the Balanced Output Transconductance Amplifier (BOTA). In the paper we also document ano... [more] In this paper a new active element for the realization of current-mode analog blocks Current Follower Transconductance Amplifier (CFTA) is presented. The element is a combination of the Current Follower (CF) and the Balanced Output Transconductance Amplifier (BOTA). In the paper we also document another extended active element CFTA which has more current outputs than can be realized by the UCC-N1B circuit, which was developed at our workplace. The application of this active element is shown on the realization of current-mode second-order universal frequency filters of the type SIMO (single-input-multi-output) and MISO (multi-input-single-output). The circuit structure consists of three active and three passive elements. The circuit was analyzed using signal-flow graphs. The properties of the proposed universal filter were subjected to a sensitivity analysis and AC analysis using PSpice software.

• Current-mode multifunction filter using single multi-output current amplifier,

  Norbert Herencsar, Jaroslav Koton, Ivo Lattenberg, Kamil Vrba

  Journal of Active and Passive Electronic Devices,. 01/2011; 6(3-4):pp. 209-215..

  In this paper a new topology of current-mode multifunction frequency filters employing a single Multi-Output Current Amplifier (MOCA) is shown. The general method of filter design using an MOCA amplifier, when the initial design starts from a simple autonomous circuit, is shown. The design of intern... [more] In this paper a new topology of current-mode multifunction frequency filters employing a single Multi-Output Current Amplifier (MOCA) is shown. The general method of filter design using an MOCA amplifier, when the initial design starts from a simple autonomous circuit, is shown. The design of internal transistor structure of the MOCA, which comes out from the internal structure of the second-generation current-conveyor (CCII+/-), is presented. It is used for the implementation of the proposed multifunction filter. The properties of the proposed second-order multifunction filter were subjected to a theoretical analysis using signal-flow graphs and AC analysis using the PSPICE software.

• Resistorless current-mode all-pass section using third-generation current controlled conveyor,

  Norbert Herencsar, Kamil Vrba, Aslihan Kartci, Abhirup Lahiri

  Proceedings of the 6th International Conference on Teleinformatics - ICT 2011,, Dolni Morava, Czech Republic; 01/2011

  This paper presents new realization of current-mode first-order all-pass filter using single third-generation current controlled conveyor (CCCIII) as the active element and one floating capacitor as the only passive component. The proposed filter requires no external resistor and is electronically a... [more] This paper presents new realization of current-mode first-order all-pass filter using single third-generation current controlled conveyor (CCCIII) as the active element and one floating capacitor as the only passive component. The proposed filter requires no external resistor and is electronically adjustable by varying the electronically controllable intrinsic resistance of the X terminal of the CCCIII. Hence, the circuit is resistorless, no component-matching constraints are required, and it has low sensitivity. The circuit realizes non-inverting type of all-pass filter. The non-idealities of the proposed circuit are also analyzed. The theoretical results are verified by SPICE simulations using transistor model parameters NR200N-2X NPN and PR200N-2X PNP of bipolar arrays ALA400-CBIC-R from AT&T.

• Current-mode dual-phase precision full-wave rectifier using current-mode two-cell winner-takes-all (WTA) circuit,

  Jaroslav Koton, Abhirup Lahiri, Norbert Herencsar, Kamil Vrba

  Radioengineering,. 01/2011; 20(2):pp. 428-432..

  In addition to the recently proposed full-wave rectifier by Prommee et al. [25] using voltage-mode (VM) two-cell winner-takes-all (WTA) circuit, we present currentmode (CM) precision full-wave rectifier using CM two-cell WTA circuit. The popular Lazzaro’s CM WTA circuit has been employed for the pur... [more] In addition to the recently proposed full-wave rectifier by Prommee et al. [25] using voltage-mode (VM) two-cell winner-takes-all (WTA) circuit, we present currentmode (CM) precision full-wave rectifier using CM two-cell WTA circuit. The popular Lazzaro’s CM WTA circuit has been employed for the purpose and there is no requirement of inverting the input signal as in [25]. Also, dual complimentary phases of the output current signal are available from high-output impedance terminals for explicit utilization. As compared to many recently proposed CM rectifiers using complex active devices, e.g. dual-X current conveyor or universal voltage conveyor, our circuit is very compact and requires a total of 21 transistors. SPICE simulation results of the circuit implemented using 0.35 μm TSMC CMOS technology are provided which verify the workability of the proposed circuit.

• Supplementary first-order all-pass filters with two grounded passive elements using FDCCII,

  Bilgin Metin, Norbert Herencsar, Kirat Pal

  Radioengineering,. 01/2011; 20(2):pp. 433-437..

  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 not element-matching restriction. The presented all-pass filter circuits can be made electronically tunab... [more] 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 not 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.

• Novel voltage conveyor with electronic tuning and its application to resistorless all-pass filter

  Norbert Herencsar, Jaroslav Koton, Kamil Vrba, Bilgin Metin

  Proceedings of the 2011 34th International Conference on Telecommunications and Signal Processing (TSP),, Budapest, Hungary; 01/2011

  In this paper, a new CMOS minus-type currentcontrolled third-generation voltage conveyor (CC-VCIII–) is presented. As application example using the presented new active building block a novel voltage-mode first-order all-pass filter is proposed, where instead of floating resistor the electronically ... [more] In this paper, a new CMOS minus-type currentcontrolled third-generation voltage conveyor (CC-VCIII–) is presented. As application example using the presented new active building block a novel voltage-mode first-order all-pass filter is proposed, where instead of floating resistor the electronically controllable intrinsic resistance of the Y terminal is used. Hence, the circuit is resistorless and it shows low sensitivity performance. The behavior of the all-pass filter is verified by SPICE simulations and the TSMC 0.35 um level 3 CMOS process parameters are used to confirm the theoretical analysis.

• Voltage-mode MOS-only all-pass filter

  Bilgin Metin, Emre Arslan, Norbert Herencsar, Oguzhan Cicekoglu

  Proceedings of the 2011 34th International Conference on Telecommunications and Signal Processing (TSP),, Budapest, Hungary; 01/2011

  In this study, a simple voltage-mode first-order all-pass (AP) filter implementation is presented which employs only MOS transistors instead of active elements like CCII, CDBA, FTFN, etc. that include large number of transistors. Transconductance (gm) and gate-to-source parasitic capacitance (Cgs) o... [more] In this study, a simple voltage-mode first-order all-pass (AP) filter implementation is presented which employs only MOS transistors instead of active elements like CCII, CDBA, FTFN, etc. that include large number of transistors. Transconductance (gm) and gate-to-source parasitic capacitance (Cgs) of the transistors are employed to form the AP transfer function. It is shown that simulations are in good agreement with the theoretical results.

• Current-mode precision full-wave rectifier using two WTA cells

  Jaroslav Koton, Abhirup Lahiri, Norbert Herencsar, Kamil Vrba

  Proceedings of the 2011 34th International Conference on Telecommunications and Signal Processing (TSP),, Budapest, Hungary; 01/2011

  In this paper a fully CMOS implementation of current-mode full-wave precision rectifier is presented. The structure is generally based on the recently presented Lazzaro's winner-takes-all (WTA) circuit. The rectifier has been implemented using the 0.35 um CMOS technology and its behavior verifie... [more] In this paper a fully CMOS implementation of current-mode full-wave precision rectifier is presented. The structure is generally based on the recently presented Lazzaro's winner-takes-all (WTA) circuit. The rectifier has been implemented using the 0.35 um CMOS technology and its behavior verified by SPICE. The simulation results shown feasibility to process signals of frequencies up to 20 MHz.

• New MOS-C realization of transadmittance type all-pass filter using modified CBTA,

  Norbert Herencsar, Abhirup Lahiri, Jaroslav Koton, Mehmet Sagbas, Umut E. Ayten, Kamil Vrba

  Proceedings of the International Conference on Applied Electronics - APPEL 2011,, Pilsen, Czech Republic, accepted; 01/2011

  This paper reports a new CMOS realization of transadmittance type first-order all-pass filter (TA-APF) using an active building block (ABB) called modified current backward transconductance amplifier (MCBTA). With a simple matching condition, the proposed TA-APF can be created using only one MCBTA, ... [more] This paper reports a new CMOS realization of transadmittance type first-order all-pass filter (TA-APF) using an active building block (ABB) called modified current backward transconductance amplifier (MCBTA). With a simple matching condition, the proposed TA-APF can be created using only one MCBTA, one grounded capacitor, and one grounded resistor, which leads to a compact circuit implementation. The current output available at high-output impedance terminal enables simple cascadibility to subsequent current-mode circuits. Using 0.35 µm TSMC CMOS technology parameters, SPICE simulation results have validated the workability of the proposed circuit.

• Current-mode precision full-wave rectifier using single DXCCII and two diodes

  Jaroslav Koton, Norbert Herencsar, Kamil Vrba

  Proceedings of the 20th European Conference on Circuit Theory and Design (ECCTD 2011),, Linkoping, Sweden; 01/2011