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Advertising LED RGB Tube with Control Unit
Frelich, Marek ; Fedra, Zbyněk (referee) ; Frýza, Tomáš (advisor)
This project discusses design of LED RGB tubes, which can be driven by asynchronous serial line. The light color of the LED tubes can be controlled in a several segments of tubes. There is made a design of control unit for driving LED tubes, which contains circuits for receiving and detection of audio signal, receiving of protocol DMX512 and also driving of LED strips. For the microprocessors there is also created a software which ensures a communication between the control unit and LED tubes, driving LEDs in the tube and creating various lighting effects.
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Adaptive active band - pass
Velička, Pavel ; Murina, Milan (referee) ; Sedláček, Jiří (advisor)
The aim of this thesis is to find and propose solutions adaptive ARC frequency bandpass filter, where it will be possible to change the bandwidth and tuning the center frequency. Centre frequency will be tuning in the range from 10kHz to 100kHz. Bandwidth is tunable to the maximum range that will enable us to select involvement. The thesis selected two methods of implementation of the filter. It made the comparison and selection of improved variants. Thesis includes calculations of the resulting variant filter and describes how to tune the filter, and then simplify the tune selected filter. Bachelor thesis includes a complete filter design for its implementation. A suitable method of electronic tuning were selected digital potentiometers controlled programmed microcontroller. This method was also subsequently implemented.
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Application possibilities of controllable current amplifier
Bradáč, Josef ; Koton, Jaroslav (referee) ; Jeřábek, Jan (advisor)
This thesis deals with the application using digitally controlled current amplifiers DACA (Digitally Adjustable Current Amplifer), which was developed at the Department of Telecommunications FEEC in cooperation with ON Semiconductor in 2010. In introduction is decribed the topic of active filters and oscillators. Farther active current components, besides DACA are described current conveyor UCC (Universal Current Conveyor), current amplifier DO-CF (Dual-Output Current Follower), MO-CF (Multiple-Output Current Follower) and FD-CF (Fully Diferential Current Follower) and operational transconductant amplifier BOTA (Balanced-Output Operational Transconductance Amplifer) and MOTA (Multiple-Output Operational Transconductance Amplifier). The following is a compilation of theories circuits using signal flow graphs, which are designed using a simulated filter circuits to control the cutoff frequency or the quality factor. Then design and simulation with auxiliary oscillator circuit AGC for controlling the oscillation frequency. Simulations are conducted with ideal models and with models that include some real properties. The conclusion of this work is devoted to the printed circuit board design for a selected filter circuit realization and measurement.
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Frequency filters using current active elements
Homola, Radek ; Lattenberg, Ivo (referee) ; Koton, Jaroslav (advisor)
This master´s thesis is about MO-CF, DCCA and CC frequency filters with current active elements proposal. Current active elements, their features, structure and utilization are shown in introduction. A progress propose of universal filter is described in thesis. With the use of active elements has been established an universal filter with basic parameter changes capability (quality and limit frequency). SNAP software was used in this propose and the characteristics simulation have been done in OrCad-PSpice. For control changes of quality and limit frequency was used active element DCCA. The main circuit board of universal controlled filter was made with the EAGLE software. Created sample was measured for each type of filter, the different quality and limit frequency. These values were compared with simulated values of the filter.
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Universal active elements and their usage in frequency filters
Vencálek, Roman ; Kubánek, David (referee) ; Herencsár, Norbert (advisor)
This master’s thesis deals with the advanced universal modern active elements, such as the current and voltage conveyors. The problem with small bandwidth has been fixed due to the quick development in recent years. Current and voltage conveyors are still being researched. The good properties of conveyors promise their possible commercial usage in the future. For the research of current conveyors we can use parts of other integrated circuits and thus get elements with similar properties. This thesis suggests how to make an active filter using the DBTA and FDBTA elements which were created by “combination” of the universal current and voltage conveyor. Simulations were carried out on selected circuits containing the DBTA to verify their properties. It was for finding out about their behaviour in real applications that the circuits were constructed. This enabled the comparison of the results acquired from the simulation programs with the ideal behaviour of the elements and with the models simulating real properties against the values acquired by measurements of the circuits.
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Digital controlled resistor
Sedlář, Petr ; Petržela, Jiří (referee) ; Šotner, Roman (advisor)
This master´s thesis deals with the design of the control circuits for digital potentiometers and their application in analog systems. Digital potentiometers are three-terminal resistors with an adjustable center connection. The digital potentiomneters enable to drive logic gates, LED drivers, LCD drivers, analog switches etc. Controlling of these mentioned devices is possible by the I2C 2- wire serial bus (invented by Philips). The digital potentiometers are used to control of the primary parameters like cut-off frequency and quality factor in the state variable filter and cut-off frequency in a passive filter. Both filters are simulated in PSpice and then compared with the measured results. Next parts of this master's thesis are a computer program and a exemplary protocol.
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Analog spectrum analyzer
BUŠEK, Pavel
The task of this bachelor thesis was to build and measure a simple spectrum analog analyzer. Analyzer works with active frequency filters. The first part of the thesis introduces principles of the theory of frequency filters. The second part deals with development of eight-pass frequency analyzer and measurement of its parameters.
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