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Speed enhancement techniques for comparator-based switched-capacitor circuitsWong, Kim Fai January 2010 (has links)
University of Macau / Faculty of Science and Technology / Department of Electrical and Electronics Engineering
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A switched-capacitor analysis metal-oxide-silicon circuit simulatorJan, Ying-Wei. January 1999 (has links)
Thesis (Ph. D.)--Ohio University, March, 1999. / Title from PDF t.p.
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A 20-GHz bipolar varactor-tuned VCO using switched capacitors to add tuning range /Stewart, Malcolm D., January 1900 (has links)
Thesis (M. App. Sc.)--Carleton University, 2003. / Includes bibliographical references (p. 140-143). Also available in electronic format on the Internet.
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A comparative study of capacitor voltage balancing techniques for flying capacitor multi-level power electronic convertersYadhati, Vennela, January 2010 (has links) (PDF)
Thesis (M.S.)--Missouri University of Science and Technology, 2010. / Vita. The entire thesis text is included in file. Title from title screen of thesis/dissertation PDF file (viewed July 26, 2010) Includes bibliographical references (p. 96-102).
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System for wireless, automated and continuous monitoring of resonant frequency of an inductor - capacitor circuitSajeeda. January 2004 (has links) (PDF)
Thesis (M.S.)--Montana State University--Bozeman, 2004. / Typescript. Chairperson, Graduate Committee: Todd J. Kaiser. Includes bibliographical references (leaves 169-171).
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Speed, Power Efficiency, and Noise Improvements for Switched Capacitor Voltage ConvertersUzun, Orhun Aras 16 June 2017 (has links)
Switched-capacitor (SC) DC-DC converters provide a viable solution for on-chip DC-DC conversion as all the components required are available in most processes. However, power efficiency, power density characteristics of SC converters are adversely affected by the integration, and characteristics such as response time and noise can be further improved with an on-chip converter. An analysis on speed, power efficiency, and noise performance of SC converters is presented and verified using simulations. Based on the analysis two techniques, converter-gating and adaptive gain control, are developed. Converter-gating uses a combination of smaller stages and reconfiguration during transient load steps to improve the power efficiency and transient response speed. The stages of the converter are also distributed across the die to reduce the voltage drop and noise on power supply. Adaptive gain control improves transient response through manipulation of the gain of the integrator in the control loop. This technique focuses on improving the response time during converter reconfiguration and offers a general solution to transient response improvement instead of focusing on the worst case scenario which is usually the largest transient load step. The techniques developed are then implemented in ST 28nm FDSOI process and test methodologies are discussed.
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Novel zero-voltage switching techniques for pulse-width-modulated convertersHua, Guichao 24 March 2009 (has links)
Two new classes of soft switching pulse-width-modulated (PWM) converters, named zero-voltage-switched (ZVS) PWM converters and zero-voltage-transition (ZVT) PWM converters, are proposed.
The proposed ZVS-PWM converters combine the merits of conventional PWM and ZVS-QRC techniques. They are capable of regulating the output for a wide load and input voltage range while maintaining constant-frequency operation. By employing a saturable inductor, the load range under which ZVS is maintained can be significantly extended without increasing the voltage stress of the power switch. The parasitic oscillations between the diode junction capacitance and the resonant inductor are also significantly reduced.
In the new class of ZVT-PWM converters, both the power switch and the rectifier diode are operated with zero-voltage switching, and are subjected to low voltage and current stresses associated with those in their PWM counterparts. Thus switching losses are significantly reduced at a slight increase in conduction losses. In addition, the circuit optimization is simplified because of constant-frequency operation.
The operation principles of the proposed converters are described by using several examples. Several breadboarded converters are implemented to verify the theoretical analysis and to demonstrate the feasibility of the proposed technologies. / Master of Science
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Active capacitor voltage stabilisation in a medium-voltage flying-capacitor multilevel active filterHansmann, Chirstine Henriette 03 1900 (has links)
Thesis (MScEng (Electrical and Electronic Engineering))--University of Stellenbosch, 2005. / A switching state substitution must be developed that will make use of both single-phase
redundancies and three-phase redundancies in the flying-capacitor topology. Losses should
be taken into consideration and the algorithm must be designed for implementation on the
existing PEC33 system, with on-board DSP (TMS320VC33) and FPGA (EP1K50QC208).
The specific power-electronics application is a medium-voltage active filter.
Existing capacitor voltage stabilisation schemes are investigated and a capacitor-voltage
based algorithm is developed that is investigated in parallel with the Donzel and Bornard
algorithm. Detailed simulation models are built for the evaluation of both existing and the
proposed algorithm. Three-phase control is also evaluated.
Timing analysis of the proposed algorithm shows that a DSP-only implementation of the
proposed capacitor-based solution is not feasible. Detail design of the digital controller
hereof is implemented in VHDL. Finally, a four-cell controller is fitted into the FPGA. A
scalable hardware sorting architecture is utilised.
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Low voltage switched capacitor circuits for lowpass and bandpass [delta sigma] convertersKeskin, Mustafa 07 December 2001 (has links)
The most accurate method for performing analog signal processing in MOS
(metal-oxide-semiconductor) integrated circuits is through the use of switched-capacitor
circuits. A switched-capacitor circuit operates as a discrete-time signal
processor. These circuits have been used in a variety of applications, such as
filters, gain stages, voltage-controlled oscillators, and modulators.
A switched-capacitor circuit contains operational amplifiers (opamps), capacitators,
switches, and a clock generator. Capacitors are used to define the state
variables of a system. They store charges for a defined time interval, and determine
the state variables as voltage differences. Switches are used to direct
the flow of charges and to enable the charging and discharging of capacitors.
Nonoverlapping clock signals control the switches and allow charge transfer between
the capacitors. Opamps are used in order to perform high-accuracy charge
transfer from one capacitor to another.
The goal of this research is to design and explore future low-voltage switched-capacitor
circuits, which are crucial for portable devices. Low-voltage operation
is needed for two reasons: making reliable and accurate systems compatible with
the submicron CMOS technology and reducing power consumption of the digital
circuits.
To this end, three different switched-capacitor integrators are proposed, which
function with very low supply voltages. One of these configurations is used to
design a lowpass ����� modulator for digital-audio applications. This modulator
is fabricated and tested demonstrating 80 dB dynamic range with a 1-V supply
voltage.
The second part of this research is to show that these low-voltage circuits are
suitable for modern wireless communication applications, where the clock and
signal frequencies are very high.
This part of the research has focused on bandpass analog-to-digital converters.
Bandpass analog-to-digital converters are among the key components in
wireless communication systems. They are used to digitize the received analog
signal at an intermediate center frequency. Such converters are used for digital
FM or AM radio applications and for portable communication devices, such as
cellular phones. The main block, in these converters, is the resonator, which is
tuned to a particular center frequency. A resonator must be designed such that
it has a sharp peak at a specific center frequency. However, because of circuit
imperfections, the resonant peak gain and/or the center frequency are degraded
in existing architectures.
Two novel switched-capacitor resonators were invented during the second
part of this research. These resonators demonstrate superior performance as
compared to previous architectures. A fourth-order low-voltage bandpass �����
modulator, using one of these resonators, has been designed. / Graduation date: 2002
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Tecnicas de interpolacao em filtros multiritmo com condensadores comutados para Interfaces Analogicas com filtragem de alta-frequencia = Multirate Switched-Capacitor interpolation techniques for very high-frequency Analog Front-End filtering / Multirate Switched-Capacitor interpolation techniques for very high-frequency Analog Front-End filteringU, Seng-Pan January 2002 (has links)
University of Macau / Faculty of Science and Technology / Department of Electrical and Electronics Engineering
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