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Direct realization of the transfer function using modern fuctional blocks
Vyskočil, Jiří ; Petržela, Jiří (referee) ; Dostál, Tomáš (advisor)
The aim of my bachelor’s thesis is a direct realization of the transfer function using modern functional blocks. It is a circuit design of multifunction frequency-selection filters. A merit of the direct realization of the transfer function is for example an easy modification of the circuit design using the signal flow graph. These circuit designs can work in current and voltage modes. My task is to design a few such designs using modern function blocks. Then I verify their function and basic characteristics, I make tolerance and sensitivity analyses and lastly I scrutinize effects of parasitic phenomena and real building components.
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Design of frequency filters with active current elements
Hort, Jiří ; Jeřábek, Jan (referee) ; Vrba, Kamil (advisor)
This bachelor's thesis deal with designing frequency filters with current active elements. Preamble is devoted to description of basic properties and division of filters. Next part presents some way of designing frequency filter. The element CMI (Current Mirror and Inverter) seems like optimal possible solution for application working in purely current mode. To design purposes serves generalized version GCMI. This thesis describes way of designing the autonomous circuit based on full admitance nets with one and two active elements CMI. Several autonomous circuits with four or five passive elements are derived from every admitance network. Individual autonomous circuits are then presented in chart with their characteristic equation. In conclusion is shown design of selected multifunction frequency filter working in current mode as in voltage mode together with characterization for its various transmission functions.
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High-order frequency filters using modern active elements
Chrást, Jakub ; Minarčík, Martin (referee) ; Jeřábek, Jan (advisor)
The bachelor thesis deals with the designing of active frequency filters of the second – order which is useful for the construction of cascade high – order filters. These filters were designed by means of autonomous circuits. Multiple current mirror and inverter MCMI, current operational amplifier COA and current differencing transconductance amplifier CDTA were used as active elements. Designing is focused on the circuits using MCMI. Designed filters work in current mode. In the introductory part there are described general characters of frequency filters. The second part includes the methods of construction high – order filters, the third part contains the description of active elements used. The design we can find in the fourth part. The functionality of filters was verified by computer simulation. One of the optimal filters was practically verified by available component UCC 0520. Two other filters were used for the construction of the fourth – order filter.
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Design of filters in current, voltage and hybrid modes with OA, using autonomous curcuits
Jašek, František ; Minarčík, Martin (referee) ; Vrba, Kamil (advisor)
This bachelor‘s thesis describes the procedure of design of frequency filters with operational amplifier using autonomous circuit. At first there is the procedure of an inference common and autonomous circuits with operational amplifier, of which they are follow on derived know and unknown engagement of frequency filters in voltage, current and hybrid mode. In all these inference frequency filters were determine a transmission function, according them is evidently about which frequency filters is discussed (low pass, high pass, band pass, band stop). The derived filter circuits are then selected two unknown involvement, which is set out in detail the procedure in the design of the frequency filter. Both suggestion circuits was verified by a simulation which results are noticed in this thesis and sequentially was made an experimental verified by mounting product in SMD. On this product was made a metering of a transmission and phase frequency characterization which was recorded in the graph. In fine there is a description of propriety of suggestion frequency filters for a practically use in this production.
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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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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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Design of new V/I and I/V converters for the measurement of current-mode filters
Jarník, Lukáš ; Polák, Josef (referee) ; Langhammer, Lukáš (advisor)
This master’s thesis deals with problems of analog differential converters, which are used in measuring circuits working in the current mode. The aim of this thesis is to propose a new voltage to current and current to voltage converter, that should influence measured frequency properties as little as possible. Commercial active elements are use to design converters. Active components are compared on the basis of properties as bandwidth and slew rate. Designed converters are simulated in Orcad PSpice program. Converters, of the best behavior are practically implemented and measured. Measured and simulated values are compared.
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Multifunction frequency filters using GCMI
Voráč, Ladislav ; Minarčík, Martin (referee) ; Jeřábek, Jan (advisor)
At the beginning of my work are the frequency filter possibilities and their use discussed. I continue with the basic theoretical filter characters, their description through the use of the transfer functions, the transfer filter function of the second rank and further possible filter diversification on active and pasive ones. In the next chapter, there is a current mode introduced with its use and reasons why to pick it up. As next are several active current items descriped, that will be used for construction of the frequency filter of the second rank. The most used item for the application in the pure current mode is GMCI, which easily means Generalized Current Mirrors and Inventors. It is obvious already from its name what does it do, mirror reflecting and inverting. The next chapter talks about the concept method of the autonomous circuit, where in several blocks is the process of the frequency filter concept to be found. Last four chapters are focused on the detailed frequency filters concept, with all its active elements and their simulations. One of the circuit was choosen for the practical realization and at the conclusion it shows the comparison of the measured and simulated transfer parameters.
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Analysis, features and applications of available current mode multipliers
Miksl, Jan ; Jeřábek, Jan (referee) ; Šotner, Roman (advisor)
The diploma thesis deals with analysis, validation, measurement of parameters of the commercially available current multiplies (namely the EL2082 and EL4083) and their applications in practice. Control analysis are carried out in OrCAD PSpice program and compared with values from datasheets. Control analysis are focused on AC and DC characteristics of these active blocks. There are discusses the input impedance, the output impedance, the current gain and the possibility of electronic adjusting. The parameters of the elements were verified by measurements. Proposals for circuit applications (selective circuit, oscillator, frequency filter) with EL2082 and EL4083 are presented and analyzed in the program OrCAD. Three oscillator circuit designs are experimentally tested and the results are compared with the theoretical expectations and simulations in OrCAD. The possibility of electronic control for oscillators is examined. Also the sensitivity and the tolerance analysis are carried out. The constructional details of oscillators are presented at the end of this work.
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Frequency filters with difference current amplifier
Jirounek, Matěj ; Lattenberg, Ivo (referee) ; Vrba, Kamil (advisor)
This master´s thesis deals with the differential filters working in the current mode. It is dealt with the design methodologies of these filters and conversion circuits from voltage to current mode. Own work deals with 4 types of differential participation of structures. In this work there has been used programs SNAP and OrCAD. These programs were used for simulations of filters to proposed proper design. Results from this thesis is showed by graphs.
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