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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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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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Fully-differential frequency filters with nontraditional active elements
Dvořák, Jan ; Koton, Jaroslav (referee) ; Jeřábek, Jan (advisor)
Bachelor's thesis deals with designs of fully-differential frequency filters which operate in current mode where it is possible to control their parameters by change the transconductance or the amplification. The first part divides and describes in general frequency filters. Furthermore, there are described active elements together with their simple simulation models. The second part describes the design of frequency filter by M-C signal-flow graph and methods of transforming final circuit to fully-differential structure. Next part presents several structures of the second-order filter with their simulations in non-differential and fully-differential forms. Last part presents designs of boards of printed circuits and measurement results of two chosen circuits.
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Higher-order current mirror filters
Semmler, Petr ; Jeřábek, Jan (referee) ; Lattenberg, Ivo (advisor)
The bachelor's thesis deal with designing frequency filters fourth and sixth rule with current component CMI, GCMI and MCMI and with multi-output current mirrors. The introduction presents basic information about frequency filters divided base several views. Next information attention about current mirrors with divided base several views. Theory part is closed information about current component GCMI, CMI, MCMI. Second part my bachelor's thesis deal manual designing frequency filter with method of autonomous circuits. This method were designed several circuit for fourth and sixth rule. Then he was always one circuit selected for the final analysis, an analysis was performed using program PSpice and Snap. The last section is devoted to the replacement of components of current mirrors. It analyzed the functionality of current mirrors including verification of the functionality of filters incorporating current mirrors.
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Design of measuring solutions for circuits with differential signals
Jemelík, Lukáš ; Hanák, Pavel (referee) ; Jeřábek, Jan (advisor)
This master´s thesis deals about a measuring structures of elements working at a current mode. There were outlined structures for measuring input and output impedance. These structures were simulated for DACA element. It deals with a voltage to current and current to voltage converters. All structures and converters were simulated at computer program PSpice. Selected variant were practically verified and control measuring was realized.
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Analysis of differential and non-differential filtering structures with adjustable current amplifier
Dvořák, Jan ; Vrba, Kamil (referee) ; Jeřábek, Jan (advisor)
The master thesis deals with designs of the single-ended and the fully-differential secondorder frequency filters with adjustable parameters. This filters operate in the current mode where main element is the current amplifier DACA (Digitally Adjustable Current Amplifier). The first part describes basic behaviour of frequency filters and distribution according to filter funcion, used parts and structure. The second part of thesis describes the design of the frequency filters by the M-C signal-flow graphs and the transformating single-ended structures to the fully-differential forms. The next part deals with properties of the active elements and their simulation models. The following part describe six circuits of the frequency filters with adjustable parameters and their simulations. Four simulation models with different properties were used for simulating of the DACA in the each circuits. The last part deals with the practical design and measurement of the selected frequency filters.
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Fully-differential frequency filter designing with current active elements using signal-flow graphs method
Štork, Petr ; Jeřábek, Jan (referee) ; Langhammer, Lukáš (advisor)
This master’s thesis deals with designing of fully-differential current-mode frequency filters using signal-flow graphs method. The first part is focused on a general description of frequency filters, its function and division. Active elements that create these frequency filters, such as multi-output current follower (MO-CF), balanced or multi-output transconductance amplifier (BOTA, MOTA) and digitally adjustace current amplifier (DACA) are described in the following part. Next, problems and various techniques of designing such filters are discussed on a theoretic basis. In the remaining part of the thesis there are six circuits of frequency filters described in detail; these connections are then transferred of passive elements to a proposed connections, with the assistance of a so-called reflection. Calculations of passive form are stated, as well as results of simulations, where nondifferential and differential variations of these designed frequency filters are compared. Finaly, it has been selected some variants of designs, which has been manufactured, then measured out and resulet has been compare between each other.
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New solutions of converters for measurement of current-mode filters
Štork, Petr ; Kubánek, David (referee) ; Jeřábek, Jan (advisor)
This bachelor’s thesis describes some new solutions of differential converters that convert voltage to current and vice versa. Such converters are necessary for measurement of frequency filters in a current mode due to absence of instruments able to mesure signals with current as signal carrier. The goal is to design such converters that should influence gauged frequency properties in a current mode as little as possible. Converters will consist of operative amplifiers with current feedback. Converters designed this way are tested using simulations from PSpice programme, where particularly wideness of band of individual solutions is tested. Simulated solutions that are the most suitable ones are practicably re-enacted and gauged. These resuls of measurement and simulations are compared.
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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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Electronically reconfigurable frequency filters
Gajdoš, Adam ; Langhammer, Lukáš (referee) ; Jeřábek, Jan (advisor)
The aim of the thesis was design of reconnection-less and electronically reconfigurable filters of SISO type with non-traditional active elements. Adjustability of bandwidth or quality factor is also required. First part of the thesis deals with theoretical analysis of filters, their operation modes and design of frequency filters using Signal-flow graph method aswell. Last but not least, electronical reconfiguration of transfer function and parasitic analysis was discussed. Another part describes active elements used in the practical part of thesis. Behaviors and design of active elements using existing circuits (e.g. UCC,EL2082) are described and their transformation into the Signal-flow graph form too. In the practical part five reconnection-less and reconfigurable filters of SISO type was designed using SNAP program. Simulations were done using Orcad program with ideal and real simulation models of active elements. Last part deals with filter design in EAGLE and experimental measurement.
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