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Measurement of Transfer and Immittance Characteristics of Active Circuit Elements
Marek, Pavel ; Vrba, Kamil (referee) ; Kubánek, David (advisor)
This diploma work deals with active circuit elements and proposals of methods for measuring of some parameters of these elements. In the opening part the work deals with general classification of elements used in electronic circuits, ideal and real current sources and power supplies. Further there are stated basic parameters and characteristics presented by producers in a catalogue sheet for active elements MAX435, OPA660, AD844 and MAA741 element which already belongs to the history of IC. Main attention is paid to active circuit elements with current sources driven by CCCS (Current Controlled Current Source) and AD844 (high speed monolithic operational amplifier). In the work there is described a method for determining of selected parameters of active elements with CCCS. Examined parameters were frequency characteristics of current transfer, input impedance and output impedance. The proposed method was verified by a computer simulation on above mentioned active elements by means of PSpice software. Findings along with the description are summarized at the end of the work. In the closing part of the work there is undertaken a real measure of AD844 element based on the proposed method and the findings are compared with particular simulations. However, at first a flat connection board was made by means of EAGLE software and then the measure was performed on it.
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Communication Systems with Digital Modulations
Spáčil, Jan ; Kubánek, David (referee) ; Číž, Radim (advisor)
The purpose of this semestral project is to explain the basic issues of simple digital modulations through the creation of simple digital modulations using direct digital synthesis. It begins with a short review of digital modulation theory and the theory about direct digital synthesis. All the technical documentation is attached, including schematics and boards of functional modulator.
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QAM Modulator
Duffek, Luděk ; Kubánek, David (referee) ; Číž, Radim (advisor)
The thesis focuses on consideration of possible ways how to realize multi-state modulators for a laboratory instrument. This instrument will illustrate signals, which partake on generation QAM modulation. The design of the laboratory instrument includes theoretic schemata and the execution of a prototype. There are theoretical facts of multi-state signals and multi-state modulations in this thesis. A simple block diagram of the laboratory instrument is made by the theory of creating quadrature amplitude modulation. For each block there are made several schemata, which are compiled to the global scheme. A printed circuit board and the structure items are made by the aid of the global scheme. The next part is devoted to a software facility for a used microprocessor, which ensures the whole function of the laboratory instrument. The final section deals with measuring, which checks the function of the modulator and the right setting coder’s constellation diagrams.
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Instruction application for Internet environment
Bartík, Rastislav ; Herencsár, Norbert (referee) ; Kubánek, David (advisor)
Ajax is quite new technology in world of web pages creation. In fact, it consits of more programming techniques like Javascript, PHP and XML. The main advantage of this technique is contacting server side on the background. This paper is focused on creating educational application for internet environment. There is written about solution for user’s interface and interface for administration.
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Controlling a power LED using ATtiny
Holubčík, Jiří ; Hanák, Pavel (referee) ; Kubánek, David (advisor)
This master´s thesis puts mind to choice and suggestion of suited type of DC/DC tension converter for power supply of power LED. It shows comparison of available types of accumulators in The Czech Republic and types of DC/DC converters used in construction of the sample. The choice of available source of energy is subordinated to final weight and size of a battery. There are also some explicit requirements for the smallest possible size and highest effictivity. So the choice is aimed only for converters with a simple coil and minimum numbers of switching elements to realize the converter, for example by SMT technology. One of many possibilities is LTC3453 circuit, which is described in this thesis, assembled and measured. On the basis of this circuit the next two samples are assembled. Here I try to suppress problems from previous circuit and expand it´s possibilities by adding the control of luminance via the microcontroller ATtiny. Then is introduced the basic description of flashlight Petzl MYO XP which is available in stores.
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