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Switching LED drivers
Doležal, Miroslav ; Pavlík, Michal (referee) ; Šteffan, Pavel (advisor)
In this bachelor’s these are three basic typologies of drivers (step down, step up, step up and down output voltage) described. Five specific integrated circuits fulfilling the requirement for supplying LED diodes are selected. The output of this thesis is the design and construction of LED driver for supplying high brightness LEDs with 900 mA constant current.
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Switching power supply based on high voltage Si/SiC MOSFET transistors
Darida, Slavomír ; Procházka, Petr (referee) ; Pazdera, Ivo (advisor)
Bachelor’sthesis is based on semestral thesis, which was focused mostly on problematic of switching power supply design with following parameters 3x400V AC/15V DC, 3,333A. Bachelor’s thesis adds algorithmic calculations of converters winding parts for forward converter and also for flyback convertor. These algorithms are created with Matlab. Next extension is design of two different forward convertor’s conceptions. Current mode PWM regulation is the first one and voltage mode PWM regulation is the second conception. Because current transformer is needed for secondary current sensing in first conception, its design is added also with algorithm calculation. Important is that both of these conceptions are using same excitation system. Excitation system functional tests are classified at the end.
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Realization of USB and LAN interface for incubator
Tydor, Maximilián ; Roubal, Zdeněk (referee) ; Steinbauer, Miloslav (advisor)
This project is focused on communication between PC and microcontroller based application. It presents few available ways to do so via modern, popular and widely used communication protocols such as USB or Ethernet. The goal of this project is to enable the microcontroller to communicate with PC and via this connection transfer the data from and to a controled application so the PC user will be able to read the actual state of the device and change its settings. As a CPU an ATmega16 is used with convertor from UART to USB type FT232BM produced by FTDI company and a UART to Ethernet convertor from Lantronix Inc. called XPort.
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LaTeX and Microsoft Power Point Presentations Convertor
Černý, Lukáš ; Čermák, Martin (referee) ; Křivka, Zbyněk (advisor)
This work deals with theoretical and practical basis for the creation of converter between LaTeX and Microsoft PowerPoint presentations. It discusses the use of LaTeX and the Beamer class for presentations, programmatic creation of PowerPoint documents using PowerPoint Primary Interop Assemblies and PresentationML. It outlines the use of the scanners and parsers generators GPLEX and GPPG respectively. It deals with the characteristics of today's tools for document conversion. And finally deals with the particular pitfalls of the design, implementation and testing of the application for conversion of documents between LaTeX platform and Microsoft PowerPoint.
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Analysis of switched-mode LED drivers
Stehlík, Ota ; Vyskočil, Pavel (referee) ; Kubíček, Michal (advisor)
The aim of this thesis is to design, produce and verify the operation of two different LED drivers for automotive industry, which controls the ultra-bright white LEDs. At the beginning of a brief introduction explaining the principle of operation of LEDs. Furthermore theory describes the functions of all three basic drivers involved as buck, boost and buck-boost. Based on the requirements are selected ICs suitable for this implementation, theoretically described their block diagrams including the individual diagrams and eventually these samples are made, revived and measured their parameters.
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Plasma Speaker
Kovář, J.
The article describes the design and construction of one-channel plasma speaker. Absence of mechanical membrane gives the plasma speaker no frequency limitation. The design consists of power source to supply control electronic for signal modulation, converter and output transformer. Modulation of audio signal is realized by integrated circuit TL 594 that provides the PWM modulation. Duty cycle and frequency is adjusted by potentiometers. Dual forward converter is used to voltage amplification. High voltage discharge between the electrodes on the secondary winding is modulated by the PWM signal and produces sound.
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Optical Convertors
Chleboun, Jan ; Dostál, Otto (referee) ; Filka, Miloslav (advisor)
Optical converters are used in various types of optical networks to provide end-users of data and voice services and also allow reception of television broadcasting, which is transmitted through optical media. The current trend is the construction of FTTH networks (Fiber To The Home), which, thanks to optical fibre, have reduced the speed or capacity, as in the case with metallic networks. The proposal is the need to consider positive and negative factors associated with building of concrete network with a specified number of users and location. Each network consists of passive and active components. Passive can be used for transmission of information, therefore they are mainly elements transmission medium. Active part includes elements for sending and receiving information transmitted by optical media. Transmitters vary their technical implementation, quality and reliability. This obviously affects the price of both active and passive parts. The cost of the operation of the network are also increased with demands of control. The advantage is the efficient management, which is guaranteed by return of the cost to build a FTTH network. Optical network with a system of remote management converters is a new trend of optical communications.
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Short Circuit Currents in the Sokolnice 400 kV Switching Station with Direct 400/110 kV Transformation Applied
Vojtěch, Pavel ; Špaček, Jaroslav (referee) ; Blažek, Vladimír (advisor)
The destination of this Bachelor´s Thesis is to explore short circuit currents for voltage level 400 kV in the switching station Sokolnice before year 1995 and after this year, when came to installation of the convertor T402 and to voltage direct 400/110 kV transformation applied. The Thesis is detecting at relation as for three-phase short circuit do for single-phase short circuits, for 400/220/110 kV primary transformation variation in voltage and for variation 400/110 kV, the change which came after connection of the convertor T402. In base of this calculation will be explored the short circuit resistance rating switching station in agreement with parameters ordered by the comp. Inc. ČEZ Prague.
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Tuner for UHF Receiver with Low Power Consuption
Kaštánek, Martin ; Vágner, Petr (referee) ; Urbanec, Tomáš (advisor)
The purpose of this work was to make a proposal for input parts of receiver for band 430 to 440 MHz. A model of chosen semiconductor triode BFP540 was created in simulation software. Possibilities how to decrease consumption of this semiconductor triode, keeping the profit, were investigated through the simulation.In compromise consumption, keeping the profit of the amplifier - an optimal operating point for this semiconductor triode UCE = 1,2 V and IC = 2 mA was found. It was tested through the testing wiring with noise microstrips conformity. Ascertained knowledge was used for construction of tuner for UHF receiver. An operating point of input amplifier of UHF receiver was owing to power supply amplifier forced for bigger effectiveness to UCE = 2,65 V and IC = 2,0 mA. Suppression of mirror frequency is provided with Helix filter of the third order, because of intermediate frequency 10,7 MHz. Mixing on intermediate frequency is made again by semiconductor triode BFP540. Selectivity of receiver is provided with intermediate frequency crystal filter 10,7 MHz with bandwidth 15 kHz. Designed input part enables reception of SSB, FM and digital types of modulation.Bandwidth intermediate frequency exit is adapted to this request To receive particular modulation , it is necessary to complete intermediate frequency signal way with appropriate intermediate frequency filter.
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Conversion of OOXML format to HTML
Tejkal, Jan ; Kosek, Jiří (advisor) ; Juřek, Michael (referee)
The theme of this work is the conversion of Word 2007 document to the HTML format. The work contains the analysis of existing convertors and description of their disadvantages and errors. The format of the OOXML document, especially WordprocessingML document, is described in detail. API used for work with OOXML documents is described too. The main contribution of this work is development of a new convertor of WordprocessingML documents to HTML format. This converor enables to divide the output to more parts. User can choose type of dividing: by sections or by style(s) of paragraph. The convertor is described in the last chapter.
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