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Active controllable frequency filter in current mode
Zbořil, Jan ; Petržela, Jiří (referee) ; Brančík, Lubomír (advisor)
The aiml of this work is to study the principles controllable frequency filters in the current mode. Is realized multifuctional current filter. Summarizes the general characteristic of the current components. Work focuses mainly on current conveyors CCII. Circuit is used here EL 2082 as a basic building element. The second chapter discussed the characteristics of filters, the third contains a description of the basic active circuit. The next chapter deals with the simulation, and the last presents the measured results.
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Synthesis of electronically configurable filters with modern active elements
Hricko, Tomáš ; Šotner, Roman (referee) ; Langhammer, Lukáš (advisor)
This bachelor thesis is concerned of proposal electronically configurable filters. The first part describes the basic division of frequency of filters and working modes alongside with the principle of electronically configuration. All active elements used in the proposal of presented circuit solutions are defined in the second section. The third part consist of the design of three circuits of electronically configurable filters and comparison of theory with simulation results obtained from program OrCAD PSpice. The concluding part of the work compares the experimental results of the implemented filters with the PSpice simulations.
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Electronically tunable oscillators
Polanský, David ; Šotner, Roman (referee) ; Petržela, Jiří (advisor)
The goal of bacheolor’s project introduce the reader to the basic principles of oscillator with a possibility of coherent electrical tunning frequency. Project is focused on utilization of non-standard active elements like OTA and CCII. A few wiring circuits are listed, in which it's tunning scale is calculated in PSpise program. Next these devices are compared.
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Electronically controllable frequency filters with current active elements
Suchánek, Tomáš ; Lattenberg, Ivo (referee) ; Kubánek, David (advisor)
The aim of the thesis is to study the possibilities of the electronic frequency ?lter com- posed of active elements operating in current mode. The main opportunities lie in the change control parameters, most are marginal or quality factor frequency. As the active elements are considered especially CC (Current Convejor), controllable current ampli?er DACA (Digitally Adjustable Current Ampli?er) or combination with the current tracker MO-CF (Multiple Output Current Follower). Another part will focus on the management of the above parameters using digital potentiometers and choosing the appropriate ?lter structure. The ?nal task was to digital control parameters using a PC and measuring its properties.
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Application of modern active blocks in harmonic oscillators
Votýpka, František ; Kubánek, David (referee) ; Slezák, Josef (advisor)
This work deals with using modern active functional blocks in electronic circuits. These blocks have better features than classical operational amplifiers and are characterized especially by working in current mode. Therefore these blocks can be used in higher frequencies. Using those blocks it is possible to design e.g. electronically variable-frequency filters of types low-pass filter, high-pass filter, band-pass filter, etc. Then it is also possible to easily realize electronically variable-frequency oscillators. This work is focused on some of these blocks, their basic characteristics and principles. Also three oscillators with current conveyors of second generation are designed. Its made simulation, sensitivity and tolerance analysis and magnitude stabilization. Everything is performed in OrCAD PSpice program. These made oscillators are electronic tunable in the band frequency ones of MHz.
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Low voltage low power current conveyor CCII
Kadaňka, Petr ; Vávra, Jiří (referee) ; Khateb, Fabian (advisor)
This paper is focused on comparing CCIIs by their construction principle. It researchs differences between gate-driven and bulk-driven approach, and between design based on current mirrors or operational amplifier. Designed current conveyor functionality is verified by SPICE simulation. Main objective of this work is to obtain current conveyor with lowest possible supply voltage and minimal power consumption.
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Unconventional Circuit Elements for Ladder Filter Design
Shaktour, Mahmoud ; Dobeš,, Josef (referee) ; Mišurec, Jiří (referee) ; Biolek, Dalibor (advisor)
Kmitočtové filtry jsou lineární elektrické obvody, které jsou využívány v různých oblastech elektroniky. Současně tvoří základní stavební bloky pro analogové zpracování signálů. V poslední dekádě bylo zavedeno množství aktivních stavebních bloků pro analogové zpracování signálů. Stále však existuje potřeba vývoje nových aktivních součástek, které by poskytovaly nové možnosti a lepší parametry. V práci jsou diskutovány různé aspekty obvodů pracujících v napěťovém, proudovém a smíšném módu. Práce reaguje na dnešní potřebu nízkovýkonových a nízkonapěťových aplikací pro přenosné přístroje a mobilní komunikační systémy a na problémy jejich návrhu. Potřeba těchto výkonných nízkonapěťových zařízení je výzvou návrhářů k hledání nových obvodových topologií a nových nízkonapěťových technik. V práci je popsána řada aktivních prvků, jako například operační transkonduktanční zesilovač (OTA), proudový konvejor II. generace (CCII) a CDTA (Current Differencing Transconductance Amplifier). Dále jsou navrženy nové prvky, jako jsou VDTA (Voltage Differencing Transconductance Amplifier) a VDVTA (Voltage Differencing Voltage Transconductance Amplifier). Všechny tyto prvky byly rovněž implementovány pomocí "bulk-driven" techniky CMOS s cílem realizace nízkonapěťových aplikací. Tato práce je rovněž zaměřena na náhrady klasických induktorů syntetickými induktory v pasivních LC příčkových filtrech. Tyto náhrady pak mohou vést k syntéze aktivních filtrů se zajímavými vlastnostmi.
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Fully-differential frequency filters with controllable active elements
Zapletal, Miroslav ; Polák, Josef (referee) ; Langhammer, Lukáš (advisor)
This bachelor thesis deals with the fully-differential frequency filters that work in current-mode and the tunability is made possible by active elements. In the first part we will deal with theoretical analysis of frequency filters, and a closer approximation of a filter design method. The second part deals with designing of frequency filters using signal-flow graphs method, converting not differential structures to differential structures and comparing the results of proposed filters. In the third part will be made up our suggested filter. It will be also measured out in VUT laboratory to verifying his functionality. Last we will compare results of real detect values of differential and not differential connection. The last part is the conclusion, in which an assessment of the whole work is made.
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Fully-differential fractional frequency filters
Zapletal, Miroslav ; Dvořák, Jan (referee) ; Langhammer, Lukáš (advisor)
This diploma thesis is concentrated to fully differential and non-differential fractional-order filters with active elements. It describes how we can obtain fractional-order fully-differential filters design from non-differential design, thesis describes realization in OrCad program and simulation of this project. The first part of the thesis concerns theoretical analysis of frequency filters, active elements and fractional-order filters. The second part of the thesis includes designs of filters and simulations of differential structures and rest of non-differential structures simulation. The following part of the thesis concerns practical realization and experimental measurment of differential fractional-order filter. In the last part of this project, thesis evaluates all results which were revealed in our simulations and experimental measurment.
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Controlled analog frequency filters
Martinek, Pavel ; Koton, Jaroslav (referee) ; Minarčík, Martin (advisor)
In this bachelor’s thesis are described elements frequency filters, especially OTA amplifier, current and voltage conveyor. There're presented possibilities of control frequency-selection filters and components to control, analog multipliers, DA converters, controlled amplifiers and digitally controlled potentiometers. There are discussed some circuits of controlled filters and their possibilities of independent control of parameters f0, Q. Frequency characteristics for mentioned filters are verified simulator programme. The circuits are modified to other type filter and again frequency charakterestics are verified simulator programme PsPice.
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