• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 61
  • 13
  • 7
  • 6
  • 4
  • 2
  • 2
  • 1
  • Tagged with
  • 96
  • 31
  • 24
  • 18
  • 18
  • 16
  • 13
  • 13
  • 13
  • 12
  • 12
  • 11
  • 11
  • 11
  • 11
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

Elektronicky řiditelný aktivní filtr 2. řádu / Electronically controlled active 2-nd order filter

Ševčík, Břetislav January 2009 (has links)
The diploma thesis deals with the modern design of the control circuits for digital potentiometers and their application in analog systems. The concept of the digital control is demonstrated on the electronically controlled active 2-nd order filter and programmable oscillator. The proposed design of the active filter describes a programmable active 2-nd order filter Sallen-Key. In this circuit it is possible independently programme cut-off frequency, Q factor and type of approximation with very good accuracy. The circuits of the designed filter and designed oscillator are simulated in PSpice (OrCAD), parasite effects and effects of the real parts are studied. Properties simulated circuits are compare with experimental results. These results appreciate quality and efficiency of the digitally controlled potentiometers in dependence on variable input circuit parameters. Integral part of this project is author’s universal control program called Digipot and comunications interface for many types of digital potentiometers with I2C, SPI or Up/Down interface. It is possible to use this device for many applications. The constructional details of the filter are presented at the end of this work. The software equipment is availability on enclosed CD.
62

Simulace a realizace laboratorního napájecího zdroje / Simulation and realization of laboratory DC power supply

Mach, Ladislav January 2010 (has links)
The thesis deals with analyses of the laboratory symmetrical supplies with adjustable output voltage. It also describes different kinds of current cut-out circuits and several most frequent supply connection schemes. Analyses (simulation program OrCAD) show the characteristics and behaviour of the mentioned supplies. To set the output voltage, operational amplifier structures or linear three-terminal voltage regulator are very often used. The suggested supply was tested and its parameters compared with the simulations. The value of output voltage and current can be controlled with a computer with a USB port. For controlling of the output voltage and current the digital potentiometers were used and controlled by I2C bus.
63

Analyzátor signálu v televizních kabelových rozvodech / TV Distribution Network Signal Analyzer

Matyáš, Pavel January 2011 (has links)
Aim of this project is development of the analyser for cable distributed television signals. At the beginning is a block diagram of the suggested analyser with digitally controled wideband tuner, logarithmic detector, microcontroller and a graphical display module. For each block there is a theoretical analysis, features description and description of the electronic components that were used. In the next part of this project is introduced the design of circuit schematic and printed circuit board of prototyping kit, that was used for experiments and testing of its features and parametres. Last part of this thesis focuses on finishing of a prototyping kit, development of firmware and experimental verification of the prototype's parameters.
64

Elektronicky řiditelné kmitočtové filtry s proudovými aktivními prvky / Electronically controllable frequency filters with current active elements

Suchánek, Tomáš January 2011 (has links)
The aim of the thesis is to study the possibilities of the electronic frequency ?lter com- posed of active elements operating in current mode. The main opportunities lie in the change control parameters, most are marginal or quality factor frequency. As the active elements are considered especially CC (Current Convejor), controllable current ampli?er DACA (Digitally Adjustable Current Ampli?er) or combination with the current tracker MO-CF (Multiple Output Current Follower). Another part will focus on the management of the above parameters using digital potentiometers and choosing the appropriate ?lter structure. The ?nal task was to digital control parameters using a PC and measuring its properties.
65

Elektronický měřič teploty a vlhkosti / Electronic thermometer and humidity meter

Lapáček, Petr January 2011 (has links)
This master´s thesis deals with the design of measuring station used for the temperature and humidity measurement. There is a theoretical basical description of sensores for temperature and humidity measurement in the first part. Furthermore I deal with a theoretical design of measuring system, especially with types of materials and possibilities of communication between these parts. The main part of thesis is about communication on buses I2C,UART, SPI, RS485. There is a description of function procedure of particular integrated circuit, moduluses which are used in task in the next part of thesis.In the practical part I was engaged in a functional design of autonomous system for the temperature and ralative humidity measurement. Data could be presented by the computer after connection with the station. There is a description of testing the particular circuits and the full description of function particular blocks of system in the task. I have used the program called Eagle for schemes and printed wirings designing. The copy is placed on CD ready for next using. In the last part of thesis is a brief description of program algorithm "Meteostanice", which I have created for data presentation. There is an illustration of measuring results in these last part. The task is completely ready for the realization of autonomous system of weather station with its own memory.
66

Ambulantní monitor srdečního rytmu / Ambulant Cardiac Monitor

Vaníček, Aleš January 2012 (has links)
This thesis describes the design and practical realization of a prototype mobile, battery-powered device that is able to periodically recording electrocardiogram and fotopletysmogram or blood pressure. Data from these periodic scanning is processed by microcontroller and stored on a memory card which is part of the proposed device. The device can be connected to a PC via USB like a virtual serial port.
67

Digitální nízkofrekvenční zesilovač s univerzálními vstupy / Digital audio amplifier with universal inputs

Svadbík, Pavel January 2012 (has links)
This diploma thesis deals with digital audio amplifier with universal inputs and its design. The first part describes modulation and audio formats for audio electronics. The thesis contain design of a block diagram of the digital audio amplifier and describes the requirements for functional blocks. As a basic device for audio signal processing was choosen integrated circuit STA326. The thesis continue with circuits design for each blocks with a description of their principles. The next section describes the construction and firmware for microcontroller. The last part of this diploma thesis is targeted on the presentation of the measured parameters of the amplifier. The conclusion summarizes the results that have been achieved and advantages and disadvantages of the digital audio amplifier prototype.
68

Hybridní řídicí systém pro quadrokoptéru / Hybrid Control System for Quadrocopter

Sojka, Stanislav January 2013 (has links)
This thesis deals with the design and theoretical description of the hybrid control system for quadrocopter. First, a mathematical model is presented, sensors needed for development and their principles. This work shows the system architecture design and scheme of communication channels between the blocks. Implementation section discusses specific uses of computing nodes/sensors and their settings. In this thesis there are illustrated messages sent between computing nodes and the control loop machine. It also describes how to test the sensors, measurement results and techniques for improvement.
69

Kolorimetr / Colorimeter

Škoda, Pavel January 2017 (has links)
This thesis deals with the analysis of the color parameters for their subsequent use in the design of the device, which will be used to measure their stability in continuous production. The theoretical part defines the basic concepts and knowledge needed to understand the problems. In addition, there are described individual components and sensors suitable for color measurement. The practical part deals mainly with the descrip- tion of the construction of the colorimeter, its individual parts and the creation of the control program. At the end, there are results of the testing of the product and their overall assessment
70

Energieffektivisering för trådlöst mätande av rotationshastighet

Graholski, Stefan January 2020 (has links)
Energy efficiency has made great progress in today’s technologies to contribute to a better environment and increasingly sustainable energy system. In this work will the biggest focus be to make the rotational speed sensor more energy efficient. The overall purpose in this work is to see if the implementation of the SparkFun RedBoard Artemis card together with the Bosch BMI 270 gyro sensor could be an energy efficient system to respect of the Bosch BMG-250 gyroscope and the Rigado BMD-350 development board that has been used in a previous work.  In the report was a method used to measure the current and energy consumption that occurred when the development board and gyroscope sensor was working. In this method did also a analyze went for to see if a difference occurred at current and energy consumption of the development card when the complete system was communicating with eighter I2C or SPI communication. Another method that has performed in this work, was to see how much current that has been consumed when a varying amount data that have used the buffer of the Bluetooth module. The result from this work showed that the SparkFun RedBoard Artemis development card together with the Bosch BMI-270 gyroscope sensor did consume considerably more energy compared to the result that was expressed in the previous work. Also did the result show that the current consumption was the same regardless to how much data that was used in the Bluetooth modules buffer. The work concluded that the development card SparkFun RedBoard Artemis together with the Bosch BMI-270 MEMS gyroscope sensor would not be imagine to be an energy efficient system regardless to the units that was used in the previous work. / Energieffektiviteten har gjort stora framsteg inom dagens teknologier för att bidra till en bättre miljö och allt mer hållbart energisystem. Inom detta arbete läggs störst fokus på att energieffektivisera ett inbyggt sensorsystem som används för att trådlöst mäta rotationshastigheter. Det övergripande syftet för arbetet är att se om implementeringen av SparkFun RedBoard Artemis kortet tillsammans med Bosch BMI 270 gyrosensorn skulle kunna vara ett energieffektivt system till avseendet av gyroskopsensorn Bosch BMG-250 och utvecklingskortet Rigado BMD-350 som användes inom ett tidigare arbete. I rapporten användes en metod för att mäta fram den ström samt energikonsumtion som förekommer när utvecklingskortet och gyrosensorn arbetar. Inom denna metod undersöktes det även om det förekom någon skillnad på utvecklingskortets ström samt energiförbrukning när den kompletta konstruktionen kommunicerar med antingen I2C eller SPI kommunikation. Ytterligare en metod som utfördes inom detta arbete var för att se hur mycket ström som konsumeras när en varierande mängd data utnyttjar Bluetooth modulens buffert. Resultaten från arbetet visade att SparkFun RedBoard Artemis kortet tillsammans med Bosch BMI 270 gyrosensorn konsumerade mer energi jämfört med det resultat som framfördes inom det tidigare arbetet. Det visade sig även att systemets strömkonsumtion blev detsamma oavsett hur mycket data som utnyttjade Bluetooth modulens buffert. Arbetets slutsats besvaras med att SparkFun RedBoard Artemis kortet tillsammans med Bosch BMI-270 MEMS gyroskopsensorn inte skulle tänka sig vara ett mer energieffektivt system jämfört med de enheterna som användes inom det tidigare arbetet.

Page generated in 0.0294 seconds