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  • 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.
81

High power-supply rejection current-mode low-dropout linear regulator

Patel, Amit P. 08 April 2009 (has links)
Power management components can be found in a host of different applications ranging from portable hand held gadgets to modern avionics to advanced medical instrumentations, among many other applications. Low-dropout (LDO) linear regulators are particularly popular owing to their: ease of use, low cost, high accuracy, low noise, and high bandwidth. With all its glory, however, it tends to underperform switched-mode power supplies (SMPS) when with comes to power conversion efficiency, although the later generates a lot of ripple at its output. With the growing need to improve system efficiency (hence longer battery life) without degrading system performance, many high end (noise sensitive) applications such as data converters, RF transceivers, precision signal conditioning, among others, use high efficiency SMPS with LDO regulators as post-regulators for rejecting the ripple generated by SMPS. This attribute of LDO regulators is known as power supply rejection (PSR). With the trend towards increasing switching frequency for SMPS, to minimize PC board real estate, it is becoming ever more difficult for LDO regulators to suppress the associate high frequency ripple since at such high frequencies, different parasitic components of the LDO regulator start to deteriorate its PSR performance. There have been a handful of different techniques suggested in the literature that can be used to achieve good PSR performance at higher frequencies. However, each of these techniques suffers from a number of drawbacks ranging from reduced efficiency to increased cost to increased solution size, and with the growing demand for higher efficiency and smaller power supplies, these techniques have their clear limitations. The objective of this research project is to develop a novel current-mode LDO regulator that can achieve good high frequency PSR performance without suffering from the afore mentioned drawbacks. The proposed architecture was fabricated using a proprietary 1.5 um Bipolar process technology, and the measurement results show a PSR improvement of 20dB (at high frequencies) over conventional regulators. Moreover, the proposed LDO regulator requires a small 15nF output capacitor for stability, which is far smaller than some of the currently used techniques.
82

Svářečka MIG/MAG se spínaným zdrojem / MIG/MAG welder with switching power supply

Klejma, Michael January 2017 (has links)
This diploma thesis deals with design of welding power supply for MIG / MAG and MMA technique with continuous output current 120 A. The first, theoretical part is devoted to welding process technology, physical characteristics of electric arc and description of individual welding methods. The thesis also deals with the concept of power converter. The design of the switched-mode power supply is based on a full bridge topology. In order to implement advanced controls of welding power supply, the ARM Cortex M4 microprocessor was selected. Due to the large power consumption of the stepper motor for drive the welding wire, an auxiliary switched-mode power supply was also implemented. The documentation describing the realization of the welding power supply and the results of the measurements are in the last part of the thesis. The welding power supply was successfully revived and reached nominal parameters. Inert gas welding has not been tested yet, due to lack of time caused by extensive work in order to complete mechanical realization.
83

Řízený laboratorní zdroj / Controled laboratory voltage suplier

Vít, Tomáš January 2015 (has links)
The aim of my master’s thesis is the design and implementation of laboratory power supply with output parameters 0-25V and 0-2A and options to manage this resource by elements of the front panel or via a computer control program. Content is the theoretical analysis of the possibility of subsequent theoretical sources suggesting that it verified on the prototype laboratory resources.
84

An investigation into the socio-economic impact of the shortage of domestic energy supply in Tshikunda Village of Limpopo Province, Vhembe District

Netshakhuma, Milingoni Henry 07 December 2012 (has links)
Oliver Tambo Institute of Governance and Policy Studies / MPM
85

Laboratorní zdroj s vysokou účinností / High efficiency laboratory power supply

Tejmlová, Lenka January 2011 (has links)
The project shows the problems of power supply in electrical engineering. It describes the general parameters of these types of supplies and presents their characteristics. Based on these findings, it is also focused on the selection of specific elements of the laboratory supply, to reach the given parameters. It contains the recalculations of the parameters of other additional components. The overall scheme of the supply is divided into several blocks, thematically corresponded to subchapters. According to the accomplished concept the laboratory supply is realized and its parameters had been tested. Projects results are assessed at the end.
86

Assessment and Development of Advanced Power Saving and Supply Concepts For Small Automotive Electronics

TARHAN, Muhammed Mustafa January 2013 (has links)
With rising fuel prices, increasing electrification, and imminent fines on CO2 emission within the EU, the requirement for energy and cost efficient supply concepts is becomingmore and more important in the automotive industry. This thesis presents an assessmentof, and improvement for energy and cost efficient power supply concepts for low-end automotiveand light e-mobility electronic control units, containing small µCs, and analogand logic components. Specifically, linear regulators, synchronous and non-synchronous buck converters, andswitched capacitor converters are investigated and assessed theoretically. The mostpromising concept, namely a discrete buck converter, is further studied using theoreticalassessment, experiment, and simulations. The key result of this work is a concept for replacing commonly used linear regulatorsin small electronic control units (ECUs) by a more efficient supply with only a smallcost adder. Specifically, since no low-end switched converter ICs are available today, wedeveloped a buck converter with discrete control circuit. This concept provides a cheap,yet efficient alternative to linear regulators for a wide range of applications. In addition,the application of this concept is supported by component selection criteria, and also bythe developed simulation models.
87

Dvojčinný síťový spínaný zdroj / Half Bridge Switch Mode Supply

Botek, Lukáš January 2020 (has links)
This master´s thesis describes switch mode power supply and discusses the design of its individual parts. It also contains a simulation of the power part of the converter and a reseach in the area of DC/DC converters.
88

Spínaný zdroj pro elektronový mikroskop / Switching power supply for electron microscope

Jánešová, Daniela January 2020 (has links)
This thesis is about theory of switching power supplies and about a specific solution of switching power supply for electron microscope. In the beginning of the thesis are mentioned various solutions of part blocks of switching power supplies, their advanteges and disadvanteges, and their suitability for electron microscopy. In the next part of the thesis are described requirements and design scheme of switching power supply for scanning part of electron microscope. The thesis i also about technical solution and practical testing of the switching power supply and verification of its functions.
89

Univerzální napájecí zdroj s mikrokontrolérem / General-purpose power supply with microcontroller

Jorda, Ivo January 2014 (has links)
The aim of this thesis is design of adjustable switched mode power supply with symmetrical output of 25 V, and switched mode power supply with fixed output voltage of 5 V. Required maximum output current of each outputs is 3 A. At the beginning of the paper function of the basic SMPS topologies is described. Next all reqiured SMPSs are designed and chosen parts of the design are simulated. In the second half of the thesis assembly and testing of PCB are described as well as functions of programs. Last chapter contains results of meassurement of power supply paramters.
90

Experimentální spínaný zdroj s tranzistory GaN MOSFET / Experimental switching supply source with power GaN MOSFETs

Matiaško, Maroš January 2016 (has links)
This master’s thesis deals with the design of the switching power supply on the principle of high frequency converter. The goal of this thesis is construction of converter which is using GaN MOSFET transistors and SiC diodes for switching. The converter uses two switch forward power supply topology. Unusually high switching frequency was chosen for the design with power transformer with open magnetic core. The outcome of this work is functional converter which is primarily intended for educational and demonstrational purposes. Multiple parts of this converter are divided into individual blocks, which can be further used for construction of other types of switching converters.

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