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Frequency filters with untraditional combination of active elements
Filgas, Jaroslav ; Herencsár, Norbert (referee) ; Jeřábek, Jan (advisor)
The Bachelor’s thesis deals with the theory and designing of analog frequency filters of the second order, which operate in current mode and use the untraditional combination of active elements. The filters are designed by means of the autonomous circuits. Active elements used in the design is Multiple Output Current Follower MO-CF, Digitally Controlled Current Amplifier DACA, Generalized Current Mirror and Inverters GCMI, Balanced Operational Transconductance Amplifier BOTA, Inverting Current Conveyor 1st and 3rd Generation ICCI/ICCIII and Universal Voltage Conveyor UVC. The proposed filters work in current mode and their ideal and real models are verified in the simulation environment OrCad. The thesis is structured into five chapters including the conclusion. The first chapter gives the general characteristics of the frequency filters, types of filter functions, types of filters and general equations. The second chapter is devoted to the theory of the active elements. The third charter is about methods of designing and the fourth includes custom designed filters, including their transfer functions and the results verify their functionality in the simulation environment.
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Fully-Differential Frequency Filters with Modern Active Elements
Langhammer, Lukáš ; Dostál, Tomáš (referee) ; Štork, Milan (referee) ; Jeřábek, Jan (advisor)
Tato disertační práce se zaměřuje na výzkum v oblasti frekvenčních filtrů. Hlavním cílem je navrhnout a analyzovat plně diferenční kmitočtové filtry pracující v proudovém módu a využívající moderní aktivní prvky. Prezentované filtry jsou navrženy za použití proudových sledovačů, operačních transkonduktančních zesilovačů, plně diferenčních proudových zesilovačů a transrezistančních zesilovačů. Návrh se zaměřuje na možnost řídit některý z typických parametrů filtru pomocí řiditelných aktivních prvků, které jsou vhodně umístněny do obvodové struktury. Jednotlivé prezentované filtry jsou navrženy v nediferenční a diferenční verzi. Velký důraz je věnován srovnání plně diferenčních struktur s jejich odpovídajícími nediferenčními formami. Funkčnost jednotlivých návrhů je ověřena simulacemi a v některých případech i experimentálním měřením.
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Pseudo-differential fractal-order frequency filters
Alkanan, Mohamad ; Dvořák, Jan (referee) ; Sládok, Ondřej (advisor)
This bachelor´s thesis deals with pseudo-differential frequency filters of fractal order. It is a proposal of non-integer order (1 + ) of pseudo-difference filter. The introduction to the theory describes the basic properties of frequency filters, their type and use. The following is a description of pseudo-differential and differential filters. The next part of the text is devoted to filters of non-integer order. Then there is a description of the current conveyors used (UCC, DVCC and DDCC). The next part of the work is devoted to the design, which is a pseudo-differential frequency filter of fractal order (1 + ) and its subsequent mathematical description in the SNAP program. The functionality and correct behavior of the filter were verified by simulations in OrCAD. The last part of the work is devoted to the practical measurement of the filter.
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Synthesis of differential filtering structures with complex active elements
Pánek, David ; Kubánek, David (referee) ; Langhammer, Lukáš (advisor)
This document is focused on already existing single-ended frequency filters with modern active components working in current mode and their modification into fully-differential ended form. After the modification both versions were compared between each other. The first part informs about problems concerning analogue frequency filters. The second part deals with used active components - MO-CF (Multiple Output Current Follower), BOTA (Balanced transconductance amplifier), UCC (universal current conveyor), VDTA (Voltage differencing transconductance amplifier), CDTA (Current differencing transconductance amplifier) and VDCC (voltage differencing current conveyor). Four circuits have been chosen and transformed into their differential form. Two circuits have been chosen and realised into PCB and then practicaly measured in a laboratory. The last part is a summary of simulations and measured results and check of circuits behavior result.
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Circuits for Analog Signal Processing Employing Unconventional Active Elements
Khatib, Nabhan ; Brzobohatý, Jaromír (referee) ; Zaplatílek,, Karel (referee) ; Biolek, Dalibor (advisor)
Disertační práce se zabývá zaváděním nových struktur moderních aktivních prvků pracujících v napěťovém, proudovém a smíšeném režimu. Funkčnost a chování těchto prvků byly ověřeny prostřednictvím SPICE simulací. V této práci je zahrnuta řada simulací, které dokazují přesnost a dobré vlastnosti těchto prvků, přičemž velký důraz byl kladen na to, aby tyto prvky byly schopny pracovat při nízkém napájecím napětí, jelikož poptávka po přenosných elektronických zařízeních a implantabilních zdravotnických přístrojích stále roste. Tyto přístroje jsou napájeny bateriemi a k tomu, aby byla prodloužena jejich životnost, trend navrhování analogových obvodů směřuje k stále většímu snižování spotřeby a napájecího napětí. Hlavním přínosem této práce je návrh nových CMOS struktur: CCII (Current Conveyor Second Generation) na základě BD (Bulk Driven), FG (Floating Gate) a QFG (Quasi Floating Gate); DVCC (Differential Voltage Current Conveyor) na základě FG, transkonduktor na základě nové techniky BD_QFG (Bulk Driven_Quasi Floating Gate), CCCDBA (Current Controlled Current Differencing Buffered Amplifier) na základě GD (Gate Driven), VDBA (Voltage Differencing Buffered Amplifier) na základě GD a DBeTA (Differential_Input Buffered and External Transconductance Amplifier) na základě BD. Dále je uvedeno několik zajímavých aplikací užívajících výše jmenované prvky. Získané výsledky simulací odpovídají teoretickým předpokladům.
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Frequency filter
Suchánek, Tomáš ; Kubánek, David (referee) ; Káňa, Ladislav (advisor)
The main objective of this thesis is to design and implement integration that will be building block for tunable active filters 2nd range of low , high and band pass through the jet structure Sallen - Key. This work first examines the use of different types of frequency filters, the detailed design of the components and selection of a suitable operational amplifiers for participation. Practical part focuses on the production of the finished product, measure its parameters resulting in graphs.In implementing are used software such as simulation programme Micro-cap and layout editor Eagle.
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Audio signal processing in electronic circuit simulators
Paluřík, Pavel ; Herencsár, Norbert (referee) ; Kubánek, David (advisor)
This bachelor's thesis deals with the simulation of electronic circuits with a focus on the processing of audio signals. At the beginning of the work a detailed procedure and instructions for work in the selected simulation program LTspice are described. The program is free to download, so anyone can try the simulations. The import, processing and export of audio files are also described. The sound of an electric guitar, a spoken word in a male voice, rock and synth recording are then discussed in more details. The last part is devoted to detailed examples of the functions of the tested circuits. The circuits tested are high-pass filter, diode limiter and effect pedal Fuzz Face which is compared with real constructed unit. The verification of the sound from the computer simulation is subjectively evaluated at the end of the work considering similarity of simulated and real recorded audio from Fuzz Face.
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Current-Input Current-Output Active Circuit Elements and their Applications
Vávra, Jiří ; Sedláček, Jiří (referee) ; Maschke, Jan (referee) ; Biolek, Dalibor (advisor)
The thesis deals with definitions of new current- or mixed-mode circuit elements and their implementations and applications. Based on the analysis of the state-of-the-art, novel application circuits employing the above circuit elements are designed. For the purpose of the experimental verification, the active elements are implemented via commercial integrated circuits, and their applications are simulated via PSpice. The application circuits are focused on frequency filters, rectifiers, oscillators, and current-copy circuits. Selected applications are analyzed with respect on real influences, and measurements on circuit prototypes are also performed.
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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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Measurement and analysis of audio-frequency differential disturbances in distribution systems
Doseděl, Tomáš ; Havránek, Zdeněk (referee) ; Drápela, Jiří (advisor)
This thesis deals with voltage disturbances in audio-frequency propagated in distribution networks. In the theoretical part, a creation and effect of these interferences are discussed as well as current methods of their measurement. In the practical part of the thesis, a measurement device based on a frequency filter was developed. This measurement device is able to measure audio-frequency disturbances up to 250kHz without suppresion of audio-frequency disturbances. The maximum frequency on the output is limited by either 125kHz or 250 kHz filter.
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