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Design of 3rd-Order Electronically Reconfigurable Filter by Inverse Chebyshev Approximation
Kříčka, T. ; Langhammer, L.
This paper deals with the proposal of an analog filter of the 3rd-order using Inverse-Follow-the-Leader-Feedback (IFLF) topology, which uses approximation of inverse Chebyshev. The filter is working in the current mode . The main advantage of this filter is an ability to electrically reconfigure its available transfer functions. The work focuses on the use of modern active elements. For design the filters was used transconductance amplifiers, second-generation current conveyors, current followers and current amplifiers . The function of the filter is verified by simulations in the OrCad PSpice software, with the ideal and behavior models of used active elements.
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Design and analysis of electronically reconfigurable filtering structures
Kříčka, Tomáš ; Dvořák, Jan (referee) ; Langhammer, Lukáš (advisor)
This bachelor thesis deals with the proposal of analog filters with the ability of the electronic reconfiguration. The main aim was to propose three fully electronically reconfigurable filters using different methods. The work focuses on the use of modern active elements that ensure the electronic reconfiguration. Specifically on operational transconductivity amplifiers, second-generation current conveyors and current amplifiers. The transfer functions are simulated in the Orcad PSpice software, at the ideal and behavioral level. Sensitivity and parasitic analysis is applied to the two proposed filtration structures. Both structures are made on printed circuit boards, which are measured and then their transfer functions are compared with the simulated functions.
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Electronically Configurable Transfer Structures
Langhammer, Lukáš ; Hospodka, Jiří (referee) ; Vávra, Jiří (referee) ; Šotner, Roman (advisor)
Práce se zaměřuje na vývoj a výzkum v oblasti elektronicky rekonfigurovatelných přenosových struktur. Primárním cílem je návrh těchto struktur za užití moderních elektronicky řiditelných aktivních prvků. V práci je prezentováno množství elektronicky rekonfigurovatelných filtračních struktur, jež byly vytvořeny za užití různých návrhových metod. Důraz je dále kladen na možnost řídit některý z typických parametrů filtru pomocí řiditelných aktivních prvků. Práce dále obsahuje několik obvodových návrhů aktivních prvků či stavebních bloků s vhodně řešenou elektronickou řiditelností, tak, aby tyto prvky/bloky mohly být dále použity pro návrh elektronicky rekonfigurovatelných filtrů. Správnost návrhu jednotlivých zapojení je podpořena PSpice a Cadence simulacemi s modely na tranzistorové úrovni. Vybraná zapojení jsou dále realizována za pomocí dostupných aktivních prvků a podrobena experimentálnímu měření.
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Analogue emulators of fractional-order circuits
Kubát, Pavel ; Langhammer, Lukáš (referee) ; Dvořák, Jan (advisor)
Diploma thesis deals with circuits contain fractional-order elements. The first part of this paper deals with this problem, there were also described methods of design fractionalorder elements and types of circuits containing the fractiona-order elements which can be applied in practice. Used active elements for practical part can be found in the second chapter. Design of GIC circuits and implementation of fractional-order element inside the circuit are shown in the last chapture. Parasitic analysis and stability of frequency filter containing fractional-order element had been also described.
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Pseudo-differential higher-order frequency filters
Jeleček, Jiří ; Dvořák, Jan (referee) ; Sládok, Ondřej (advisor)
This Master's thesis deals with pseudo-differential frequency higher order filters working in voltage mode. The thesis deals with the description of frequency filters, their types and applications. Follows an analysis of differential and pseudo-differential transmissions. Next part contains a description of used active elements (conveyors) at thesis (CCII, DVCC, DDCC, UCC). In the last part the thesis is devoted to the own design of the pseudo-differential filter. Design functionality is verified by experimental simulation.
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Differential and pseudo-differential filtering circuits
Hrbek, Tomáš ; Bečková, Zuzana (referee) ; Jeřábek, Jan (advisor)
This bachelor thesis deals with analog frequency filters operating in differential and pseudodifferential mode. It is focused on active filters second order that use modern active elements. For specific solution is analyzed the ability to control filter parameters. It also deals with the design of fully differential filters and transformations from non-differential filters. The thesis analyzes three specific filtering solutions with which ideal simulations and simulations using third order models are performed. A printed circuit is constructed for one filter solution, its parameters are measured and compared with simulations.
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Utilizing Unconventional CMOS Techniques for Low Voltage Low Power Analog Circuits Design for Biomedical Applications
Bay Abo Dabbous, Salma ; Horský, Pavel (referee) ; Ďuračková, Daniela (referee) ; Khateb, Fabian (advisor)
Tato disertační práce se zabývá navržením nízkonapěťových, nízkopříkonových analogových obvodů, které používají nekonvenční techniky CMOS. Lékařská zařízení na bateriové napájení, jako systémy pro dlouhodobý fyziologický monitoring, přenosné systémy, implantovatelné systémy a systémy vhodné na nošení, musí být male a lehké. Kromě toho je nutné, aby byly tyto systémy vybaveny baterií s dlouhou životností. Z tohoto důvodu převládají v biomedicínských aplikacích tohoto typu nízkopříkonové integrované obvody. Nekonvenční techniky jako např. využití transistorů s řízeným substrátem (Bulk-Driven “BD”), s plovoucím hradlem (Floating-Gate “FG”), s kvazi plovoucím hradlem (Quasi-Floating-Gate “QFG”), s řízeným substrátem s plovoucím hradlem (Bulk-Driven Floating-Gate “BD-FG”) a s řízeným substrátem s kvazi plovoucím hradlem (Bulk-Driven Quasi-Floating-Gate “BD-QFG”), se v nedávné době ukázaly jako efektivní prostředek ke zjednodušení obvodového zapojení a ke snížení velikosti napájecího napětí směrem k prahovému napětí u tranzistorů MOS (MOST). V práci jsou podrobně představeny nejdůležitější charakteristiky nekonvenčních technik CMOS. Tyto techniky byly použity pro vytvoření nízko napěťových a nízko výkonových CMOS struktur u některých aktivních prvků, např. Operational Transconductance Amplifier (OTA) založené na BD, FG, QFG, a BD-QFG techniky; Tunable Transconductor založený na BD MOST; Current Conveyor Transconductance Amplifier (CCTA) založený na BD-QFG MOST; Z Copy-Current Controlled-Current Differencing Buffered Amplifier (ZC-CC-CDBA) založený na BD MOST; Winner Take All (WTA) and Loser Take All (LTA) založený na BD MOST; Fully Balanced Four-Terminal Floating Nullor (FBFTFN) založený na BD-QFG technice. Za účelem ověření funkčnosti výše zmíněných struktur, byly tyto struktury použity v několika aplikacích. Výkon navržených aktivních prvků a příkladech aplikací je ověřován prostřednictvím simulačních programů PSpice či Cadence za použití technologie 0.18 m CMOS.
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Active Filters and their Transformation to Differential Structures
Bečková, Zuzana ; Herencsár, Norbert (referee) ; Vrba, Kamil (advisor)
Bachelor thesis is considered with transformation of single--ended frequency filters to fully--differential structures. Theoretical part contains a brief introduction to frequency filters and short summary of important features of signal flow graphs. Active elements, which are used in designed filters, are shown in the third chapter. Practical part of the thesis shows five single-ended filters (one already published, four newly designed) and their transformation to fully-differential structures. Results of simulations in programms OrCAD and SNAP are shown.
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Design and implementation of behavioral block models of active elements
Lipčej, Martin ; Koton, Jaroslav (referee) ; Jeřábek, Jan (advisor)
Bachelor thesis is focused on electronically controlled modern active elements, their typical behavior and particularly on design of composite function blocks. General study of analog signal processing using active elements in current, or mixed mode is presented, including their ideal behavior. For selected basic active elements, in particular Operati- onal Transconductance Amplifier and Second-Generation Current Conveyor, were found suitable simulation models of commercially produced active elements with the aim of designing composite function blocks CCTA, VDTA and VDCC. The potential possibility of independent control of their parameters is also considered. The simulated circuits using behavioral models of real components are presented in the following chapters, including their manufacturer indicated properties and examples of parameter control. The thesis then presents the simulation results of all possible circuit variants of the three active function blocks. The main benefit of this project is the ge- neral introduction to current mode active elements, design of unconventional functional blocks using real components and the final evaluation of presented simulations, including comprarison with their theoretical behavior. The conclusion aims to summarize the most appropriate combination of components, including manufacturing of VDTA and VDCC.
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Current amplifier applications in differential frequency filters
Bokůvka, Tomáš ; Kubánek, David (referee) ; Jeřábek, Jan (advisor)
Bachelors’s thesis focuses on selection and analysis of suitable filtering structures working in current mode. In the first part, there is a common description of frequency filters in terms of function and division. The following text discusses the issues of active elements that creates basic construction of these filtering structures. Core of each circuit is formed by digitally adjustable current amplifier DACA, which enables change of amplification. Another used active elements are universal curret conveyor UCC, dual-output current follower DO-CF, multi-output current follower MO-CF, operational transconductance amplifier OTA and balanced-output transconductance amplifier BOTA. In the last part, there are described four chosen applications of frequency filters. There are introduced calculations of passive components a results of simulations. For experimental confirmation there are chosen two fully-differential structures. The end of work contains summary of measurements of these two frequency filters
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