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ContributorsDaval, Charles (Performer) / ASU Library. Music Library (Publisher)
Created2018-03-26
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DescriptionThe purpose of this project is to explore the influence of folk music in guitar compositions by Manuel Ponce from 1923 to 1932. It focuses on his Tres canciones populares mexicanas and Tropico and Rumba.
ContributorsGarcia Santos, Arnoldo (Author) / Koonce, Frank (Thesis advisor) / Rogers, Rodney (Committee member) / Rotaru, Catalin (Committee member) / Arizona State University (Publisher)
Created2014
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Description
Modern day deep sub-micron SOC architectures often demand very low supply noise levels. As supply voltage decreases with decreasing deep sub-micron gate length, noise on the power supply starts playing a dominant role in noise-sensitive analog blocks, especially high precision ADC, PLL, and RF SOC's. Most handheld and portable applications

Modern day deep sub-micron SOC architectures often demand very low supply noise levels. As supply voltage decreases with decreasing deep sub-micron gate length, noise on the power supply starts playing a dominant role in noise-sensitive analog blocks, especially high precision ADC, PLL, and RF SOC's. Most handheld and portable applications and highly sensitive medical instrumentation circuits tend to use low noise regulators as on-chip or on board power supply. Nonlinearities associated with LNA's, mixers and oscillators up-convert low frequency noise with the signal band. Specifically, synthesizer and TCXO phase noise, LNA and mixer noise figure, and adjacent channel power ratios of the PA are heavily influenced by the supply noise and ripple. This poses a stringent requirement on a very low noise power supply with high accuracy and fast transient response. Low Dropout (LDO) regulators are preferred over switching regulators for these applications due to their attractive low noise and low ripple features. LDO's shield sensitive blocks from high frequency fluctuations on the power supply while providing high accuracy, fast response supply regulation.

This research focuses on developing innovative techniques to reduce the noise of any generic wideband LDO, stable with or without load capacitor. The proposed techniques include Switched RC Filtering to reduce the Bandgap Reference noise, Current Mode Chopping to reduce the Error Amplifier noise & MOS-R based RC filter to reduce the noise due to bias current. The residual chopping ripple was reduced using a Switched Capacitor notch filter. Using these techniques, the integrated noise of a wideband LDO was brought down to 15µV in the integration band of 10Hz to 100kHz. These techniques can be integrated into any generic LDO without any significant area overhead.
ContributorsMagod Ramakrishna, Raveesh (Author) / Bakkaloglu, Bertan (Thesis advisor) / Garrity, Douglas (Committee member) / Kitchen, Jennifer (Committee member) / Arizona State University (Publisher)
Created2014
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Description
Recent changes in the energy markets structure combined with the conti-nuous load growth have caused power systems to be operated under more stressed conditions. In addition, the nature of power systems has also grown more complex and dynamic because of the increasing use of long inter-area tie-lines and the high

Recent changes in the energy markets structure combined with the conti-nuous load growth have caused power systems to be operated under more stressed conditions. In addition, the nature of power systems has also grown more complex and dynamic because of the increasing use of long inter-area tie-lines and the high motor loads especially those comprised mainly of residential single phase A/C motors. Therefore, delayed voltage recovery, fast voltage collapse and short term voltage stability issues in general have obtained significant importance in relia-bility studies. Shunt VAr injection has been used as a countermeasure for voltage instability. However, the dynamic and fast nature of short term voltage instability requires fast and sufficient VAr injection, and therefore dynamic VAr devices such as Static VAr Compensators (SVCs) and STATic COMpensators (STAT-COMs) are used. The location and size of such devices are optimized in order to improve their efficiency and reduce initial costs. In this work time domain dy-namic analysis was used to evaluate trajectory voltage sensitivities for each time step. Linear programming was then performed to determine the optimal amount of required VAr injection at each bus, using voltage sensitivities as weighting factors. Optimal VAr injection values from different operating conditions were weighted and averaged in order to obtain a final setting of the VAr requirement. Some buses under consideration were either assigned very small VAr injection values, or not assigned any value at all. Therefore, the approach used in this work was found to be useful in not only determining the optimal size of SVCs, but also their location.
ContributorsSalloum, Ahmed (Author) / Vittal, Vijay (Thesis advisor) / Heydt, Gerald (Committee member) / Ayyanar, Raja (Committee member) / Arizona State University (Publisher)
Created2011
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Description
Power management plays a very important role in the current electronics industry. Battery powered and handheld applications require novel power management techniques to extend the battery life. Most systems have multiple voltage regulators to provide power sources to the different circuit blocks and/or sub-systems. Some of these voltage regulators are

Power management plays a very important role in the current electronics industry. Battery powered and handheld applications require novel power management techniques to extend the battery life. Most systems have multiple voltage regulators to provide power sources to the different circuit blocks and/or sub-systems. Some of these voltage regulators are low dropout regulators (LDOs) which typically require output capacitors in the range of 1's to 10's of µF. The necessity of output capacitors occupies valuable board space and can add additional integrated circuit (IC) pin count. A high IC pin count can restrict LDOs for system-on-chip (SoC) solutions. The presented research gives the user an option with regard to the external capacitor; the output capacitor can range from 0 - 1µF for a stable response. In general, the larger the output capacitor, the better the transient response. Because the output capacitor requirement is such a wide range, the LDO presented here is ideal for any application, whether it be for a SoC solution or stand-alone LDO that desires a filtering capacitor for optimal transient performance. The LDO architecture and compensation scheme provide a stable output response from 1mA to 200mA with output capacitors in the range of 0 - 1µF. A 2.5V, 200mA any-cap LDO was fabricated in a proprietary 1.5µm BiCMOS process, consuming 200µA of ground pin current (at 1mA load) with a dropout voltage of 250mV. Experimental results show that the proposed any-cap LDO exceeds transient performance and output capacitor requirements compared to previously published work. The architecture also has excellent line and load regulation and less sensitive to process variation. Therefore, the presented any-cap LDO is ideal for any application with a maximum supply rail of 5V.
ContributorsTopp, Matthew (Author) / Bakkaloglu, Bertan (Thesis advisor) / Thornton, Trevor (Committee member) / Ozev, Sule (Committee member) / Arizona State University (Publisher)
Created2012
ContributorsKotronakis, Dimitris (Performer) / ASU Library. Music Library (Publisher)
Created2018-03-01
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Description
Recently, a novel non-iterative power flow (PF) method known as the Holomorphic Embedding Method (HEM) was applied to the power-flow problem. Its superiority over other traditional iterative methods such as Gauss-Seidel (GS), Newton-Raphson (NR), Fast Decoupled Load Flow (FDLF) and their variants is that it is theoretically guaranteed to find

Recently, a novel non-iterative power flow (PF) method known as the Holomorphic Embedding Method (HEM) was applied to the power-flow problem. Its superiority over other traditional iterative methods such as Gauss-Seidel (GS), Newton-Raphson (NR), Fast Decoupled Load Flow (FDLF) and their variants is that it is theoretically guaranteed to find the operable solution, if one exists, and will unequivocally signal if no solution exists. However, while theoretical convergence is guaranteed by Stahl’s theorem, numerical convergence is not. Numerically, the HEM may require extended precision to converge, especially for heavily-loaded and ill-conditioned power system models.

In light of the advantages and disadvantages of the HEM, this report focuses on three topics:

1. Exploring the effect of double and extended precision on the performance of HEM,

2. Investigating the performance of different embedding formulations of HEM, and

3. Estimating the saddle-node bifurcation point (SNBP) from HEM-based Thévenin-like networks using pseudo-measurements.

The HEM algorithm consists of three distinct procedures that might accumulate roundoff error and cause precision loss during the calculations: the matrix equation solution calculation, the power series inversion calculation and the Padé approximant calculation. Numerical experiments have been performed to investigate which aspect of the HEM algorithm causes the most precision loss and needs extended precision. It is shown that extended precision must be used for the entire algorithm to improve numerical performance.

A comparison of two common embedding formulations, a scalable formulation and a non-scalable formulation, is conducted and it is shown that these two formulations could have extremely different numerical properties on some power systems.

The application of HEM to the SNBP estimation using local-measurements is explored. The maximum power transfer theorem (MPTT) obtained for nonlinear Thévenin-like networks is validated with high precision. Different numerical methods based on MPTT are investigated. Numerical results show that the MPTT method works reasonably well for weak buses in the system. The roots method, as an alternative, is also studied. It is shown to be less effective than the MPTT method but the roots of the Padé approximant can be used as a research tool for determining the effects of noisy measurements on the accuracy of SNBP prediction.
ContributorsLi, Qirui (Author) / Tylavsky, Daniel (Thesis advisor) / Lei, Qin (Committee member) / Weng, Yang (Committee member) / Arizona State University (Publisher)
Created2018
ContributorsDavin, Colin (Performer) / ASU Library. Music Library (Publisher)
Created2018-10-05
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Description
The modern era of consumer electronics is dominated by compact, portable, affordable smartphones and wearable computing devices. Power management integrated circuits (PMICs) play a crucial role in on-chip power management, extending battery life and efficiency of integrated analog, radio-frequency (RF), and mixed-signal cores. Low-dropout (LDO) regulators are commonly used to

The modern era of consumer electronics is dominated by compact, portable, affordable smartphones and wearable computing devices. Power management integrated circuits (PMICs) play a crucial role in on-chip power management, extending battery life and efficiency of integrated analog, radio-frequency (RF), and mixed-signal cores. Low-dropout (LDO) regulators are commonly used to provide clean supply for low voltage integrated circuits, where point-of-load regulation is important. In System-On-Chip (SoC) applications, digital circuits can change their mode of operation regularly at a very high speed, imposing various load transient conditions for the regulator. These quick changes of load create a glitch in LDO output voltage, which hamper performance of the digital circuits unfavorably. For an LDO designer, minimizing output voltage variation and speeding up voltage glitch settling is an important task.

The presented research introduces two fully integrated LDO voltage regulators for SoC applications. N-type Metal-Oxide-Semiconductor (NMOS) power transistor based operation achieves high bandwidth owing to the source follower configuration of the regulation loop. A low input impedance and high output impedance error amplifier ensures wide regulation loop bandwidth and high gain. Current-reused dynamic biasing technique has been employed to increase slew-rate at the gate of power transistor during full-load variations, by a factor of two. Three design variations for a 1-1.8 V, 50 mA NMOS LDO voltage regulator have been implemented in a 180 nm Mixed-mode/RF process. The whole LDO core consumes 0.130 mA of nominal quiescent ground current at 50 mA load and occupies 0.21 mm x mm. LDO has a dropout voltage of 200 mV and is able to recover in 30 ns from a 65 mV of undershoot for 0-50 pF of on-chip load capacitance.
ContributorsDesai, Chirag (Author) / Kiaei, Sayfe (Thesis advisor) / Bakkaloglu, Bertan (Committee member) / Seo, Jae-Sun (Committee member) / Arizona State University (Publisher)
Created2016
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Description
State of art modern System-On-Chip architectures often require very low noise supplies without overhead on high efficiencies. Low noise supplies are especially important in noise sensitive analog blocks such as high precision Analog-to-Digital Converters, Phase Locked Loops etc., and analog signal processing blocks. Switching regulators, while providing high efficiency power

State of art modern System-On-Chip architectures often require very low noise supplies without overhead on high efficiencies. Low noise supplies are especially important in noise sensitive analog blocks such as high precision Analog-to-Digital Converters, Phase Locked Loops etc., and analog signal processing blocks. Switching regulators, while providing high efficiency power conversion suffer from inherent ripple on their output. A typical solution for high efficiency low noise supply is to cascade switching regulators with Low Dropout linear regulators (LDO) which generate inherently quiet supplies. The switching frequencies of switching regulators keep scaling to higher values in order to reduce the sizes of the passive inductor and capacitors at the output of switching regulators. This poses a challenge for existing solutions of switching regulators followed by LDO since the Power Supply Rejection (PSR) of LDOs are band-limited. In order to achieve high PSR over a wideband, the penalty would be to increase the quiescent power consumed to increase the bandwidth of the LDO and increase in solution area of the LDO. Hence, an alternative to the existing approach is required which improves the ripple cancellation at the output of switching regulator while overcoming the deficiencies of the LDO.

This research focuses on developing an innovative technique to cancel the ripple at the output of switching regulator which is scalable across a wide range of switching frequencies. The proposed technique consists of a primary ripple canceller and an auxiliary ripple canceller, both of which facilitate in the generation of a quiet supply and help to attenuate the ripple at the output of buck converter by over 22dB. These techniques can be applied to any DC-DC converter and are scalable across frequency, load current, output voltage as compared to LDO without significant overhead on efficiency or area. The proposed technique also presents a fully integrated solution without the need of additional off-chip components which, considering the push for full-integration of Power Management Integrated Circuits, is a big advantage over using LDOs.
ContributorsJoshi, Kishan (Author) / Bakkaloglu, Bertan (Thesis advisor) / Garrity, Douglas (Committee member) / Seo, Jae-Sun (Committee member) / Arizona State University (Publisher)
Created2016