Engineering Commons^™

A Case Study In Cmos Design Scaling For Analog Applications: The Ringamp Ldo, Steven Corum

Masters Theses

As CMOS process nodes scale to smaller feature sizes, process optimizations are made to achieve improvements in digital circuit performance, such as increasing speed and memory, while decreasing power consumption. Unfortunately for analog design, these optimizations usually come at the expense of poorer transistor performance, such as reduced small signal output resistance and increased channel length modulation. The ring amplifier has been proposed as a digital solution to the analog scaling problem, by configuring digital inverters to function as analog amplifiers through deadzone biasing. As digital inverters naturally scale, the ring amplifier is a promising area of exploration for analog …

A Low Power, Rad-Hard, Ecl Standard Cell Library, Zakaraya A. Hamdan

Masters Theses

Space exploration for life both inside and outside of our solar system demand the design and fabrication of robust, reliable electronics that can take measurements, process data, and sustain necessary operations. However, the presence of high radiation and the cold temperature of space poses a challenge to most designers. This thesis presents the design of a radiation-hardened, cold capable emitter coupled logic standard cell library with the intention of being used for space applications. The cells are designed and fabricated in a 90nm silicon germanium BiCMOS process. First, a review of emitter coupled logic is presented. Then, the design methodology …

Load Modeling And Evaluation Of Leds For Hardware Test Bed Application, Jillian M. Ruff

Masters Theses

The lighting industry was revolutionized with the emergence of LED lighting. Over the last 15 years, LED lighting device sales and utilization have grown immensely. The growth and popularity of LEDs is due to improved operation of the device when compared to previous lighting technologies. Efficient performance of the device is critical due to the growth of global energy consumption.

As nonrenewable generation fuel is finite, utilities have begun the transition to renewable energy generation. Generation and distribution systems become inherently complex to comprehend and maintain with incorporation of emerging supply and load technologies. With the unprecedented growth of LED …

A Bulk Driven Transimpedance Cmos Amplifier For Sipm Based Detection, Shahram Hatefi Hesari

Masters Theses

The contribution of this work lies in the development of a bulk driven operational
transconducctance amplifier which can be integrated with other analog circuits and
photodetectors in the same chip for compactness, miniaturization and reducing the
power. Silicon photomultipliers, also known as SiPMs, when coupled with scintillator materials are used in many imaging applications including nuclear detection. This thesis discuss the design of a bulk-driven transimpedance amplifier suitable for detectors where the front end is a SiPM. The amplifier was design and fabricated in a standard standard CMOS process and is suitable for integration with CMOS based SiPMs and commercially …

Development Of Arduino-Based Portable Systems For Electroanalytical Detection, Jiamei Huang

Masters Theses

This work presents the development of a multi-mode electroanalytical detection system based on Arduino microcontroller board. First, a multichannel impedance readout system is designed for alternating current electrokinetics (ACEK) based capacitive sensing. ACEK phenomena on 100μm interdigitated electrodes are observed via fluorescent particles as well as bioparticles, which illustrate the mechanisms of ACEK target enrichment for the capacitive sensing method. I2C multiplexer is applied to allow multiple impedance converters to work together providing continuous AC signals for ACEK capacitive sensing. Second, an electronic nose composed of three modules including a gas sensor array, a circuit for signal acquisition integrated with …

Design And Evaluation Of A Unique Weighted-Sum-Based Anger Camera, Matthew W. Seals

Masters Theses

Anger camera imaging technology has become widely popular for neutron diffraction imaging due to recent shortages in Helium-3 (He-3). Research into neutron diffraction optimized Anger camera by the Oak Ridge National Laboratory (ORNL) detectors group has provided an alternative to He-3 Tube-based detectors with a high-resolution Anger camera. However, the cost of these high-resolution Anger camera technology can make it less attractive than He-3 tubes when a large Field of View (FOV) is desired. Currently, there is a need for a lower-cost alternative to this high-resolution anger camera. Further applications for Anger camera have become of interest with the advent …

Partial Discharge Testing And Detection Under Pwm Voltage, John Meadors

Masters Theses

Partial Discharge detection and measurement is an important part of electric insulation design. However, in PWM (pulse width modulation) voltage source converter environments, the noise resulting from switching voltage (rise and fall times of tens of nanoseconds) makes detection and extraction of partial discharge difficult. Unique methods of partial discharge detection are needed to address and decouple the noise from partial discharge measurements. PWM voltage can feature high switching speeds and high dv/dt during voltage switching. These PWM voltage behaviors are not found in traditional utility high voltage applications, and the effects that this type of voltage has on insulation …

Development Of An Encrypted Wireless System For Body Sensor Network Applications, Kendra Anderson

Masters Theses

Wireless body area networks (WBAN), also called wireless body sensor networks (WBSN), consist of a collection of wireless sensor nodes used to monitor and assess various human physiological conditions, which can then be used by healthcare professionals to help them make important healthcare decisions. They can be used to prevent disease, help diagnosis a disease, or manage the symptoms of a disease. An extremely important aspect of WBAN is security to protect a patient's healthcare information, as a hacker could potentially cause fatal harm. Current security measures are implemented in software at the MAC layer and higher, not in the …

Development Of A Point-Of-Use Testing Platform For Detecting Bacteria Infection In Raw Milk, Xin Xia

Masters Theses

The detection and quantification of bacteria are essential to environment and food quality monitoring. Escherichia coli (E. coli) is a common pathogen, also a causative agent of mastitis. Traditional methods usually require samples to be tested in a laboratory. However, sending samples to remote lab increases the cost of time and money spent on delivery. Sometimes, samples can degrade during this long progress and cause inaccuracy. A low cost and reusable sensor is designed to perform on-site quantification. The sensor composed of two layers of asymmetrical mesh electrodes, which is used in coordination magnetic microparticles functionalized with bacterium-specific antibody. Immunological …

Development Of A Converter-Based Testing Platform And Battery Energy Storage System (Bess) Emulator For Microgrid Controller Function Evaluation, Dingrui Li

Masters Theses

The microgrid has attracted increasing research attention in the last two decades. Due to the development of renewable energy resources and power electronics technologies, the future microgrid will trend to be smarter and more complicated. The microgrid controller performs a critical role in the microgrid operation, which will also become more and more sophisticated to support the future microgrid. Before final field deployment and test, the evaluation and testing of the controller is an indispensable step in the controller development, which requires a proper testing platform.

However, existing simulation-based platforms have issues with potential numerical oscillation and may require huge …

Design Of Power Receiving Units For 6.78mhz Wireless Power Transfer Systems, Hoang Phuc Tran Pham

Masters Theses

In the last decade, the wireless power transfer (WPT) technology has been a popular topic in power electronics research and increasingly adopted by consumers. The AirFuel WPT standard utilizes resonant coils to transfer energy at 6.78 MHz, introducing many benefits such as longer charging distance, multi-device charging, and high tolerance of the coil misalignment. However, variations in coil coupling due to the change in receiving coil positions alter the equivalent load reactance, degrading efficiency.

In recent studies, active full-bridge rectifiers are employed on WPT receivers because of their superior efficiency, controllability, and ability to compensate for detuned WPT networks. In …

An Analog Cmos Particle Filter, Trevor Watson

Masters Theses

Particle filters are used in a variety of image processing and machine learning applications. Their main use in these applications is to gather information about a system of objects, by using partial or noisy observations collected from sensors. These observations are used to associate points of interest in the observations with objects and maintain this association through a series of observations.

In this paper I will investigate the performance of a particle filter implemented in 130nm analog CMOS hardware. The design goal of the particle filter is low-microwatt power consumption. Using analog hardware, rather than digital ASICs or CPUs I …

High-Current Integrated Battery Chargers For Mobile Applications, Gabriel Alejo Gabian

Masters Theses

Battery charging circuits for mobile applications, such as smart phones and tablets, require both small area and low losses. In addition, to reduce the charging time, high current is needed through the converter. In this work, exploration of the Buck, the 3-Level Buck and the Hybrid Buck converter is performed over the input voltage, the total FET area and the load current. An analytical loss model for each topology is constructed and constrated by experimental results. In addition, packaging and bond wire impact on on-chip losses is analyzed by 3D modeling. Finally, a comparison between the topologies is presented determining …

Design Of An Integrated Silicon Carbide Nonlinear-Carrier Pwm Controller For Boost Converter Applications, Richard Kyle Harris

Masters Theses

Power electronics consisting of a switch mode power supply with feedback control have a great number of applications, including many that require extreme environment capability, such as the aerospace and automotive industries.

Silicon carbide (SiC) is a common material in which power devices are created for use in switch mode power supplies, such as boost converters, giving those power supplies extremely high temperature capabilities. To truly realize the temperature capabilities of SiC in power supplies, an integrated SiC converter has been designed that is also high-temperature capable.

Herein, the properties of SiC integrate circuit (IC) processes are discussed and nonlinear-carrier …

Battery Energy Storage Emulation For Power System Applications, Jessica Danielle Boles

Masters Theses

The concept of energy storage for power systems has received increasingly more attention in recent decades, and the growing penetration of renewable energy sources has only escalated demand for it. Energy storage systems are excellent for balancing generation and load, for suppressing power fluctuations, and for providing other ancillary services to the grid. The Hardware Testbed (HTB) is a novel converter-based grid emulator created for studying the needs associated with high renewable penetration, but the system currently lacks a battery storage emulator. Thus, this work documents the development of a battery energy storage system (BESS) emulator for the HTB.

The …

A Practical Realization Of A Return Map Immune Lorenz Based Chaotic Stream Cipher In Circuitry, Daniel Robert Brown

Masters Theses

Some chaotic systems are advantageously capable of self-synchronizing with a like system through a single shared state. Using a plain text binary message, a single system parameter can be modulated to mask this message and transmit it securely through the single shared state. The most simple implementations of this encryption technique are, however, vulnerable to the return map attack. Using a time-scaling factor to further obfuscate the modulation process, a return map attack immunity is gained. We report on the progress towards a realization of this process in real-time analog circuitry using off-the-shelf components.

A Sub-Threshold Low-Power Integrated Bandpass Filter For Highly-Integrated Spectrum Analyzers, Benjamin David Roehrs

Masters Theses

Low-power analog filter banks provide frequency analysis with minimal space requirements, making them viable solutions for integrated remote audio- and vibration-sensing applications. In order to achieve a balance between the length of deployable service and system performance, a critical requirement of such remote sensor networks is low-power consumption, due to the constraints imposed by on-board battery cells.

In this work, the design and implementation of a sub-threshold complementary metal-oxide semiconductor (CMOS) integrated low-power tunable analog filter channel for Oak Ridge National Laboratory is presented. Project specifications required a tunable, high-order, monolithic bandpass filter channel with small chip area and low …

Cmos Based Impedance Sensing, Jinlong Gu

Masters Theses

This thesis focuses on a compact, low power circuit design for biological cell impedance sensing. Cell impedance sensing provides a new way to diagnose the cancers. Experiments done previously have shown that cancer cells have lower impedance than the normal cells, due to the thinner membrane of cancer cells. Traditional methods of cancer diagnosis require special chemicals, skilled personnel, and take long time to obtain the results. Two circuit structures are proposed in this work. One is a silicon cochlea based architecture. The other one is a current mode lock-in amplifier. Both of these two structures are able to measure …

The Design And Validation Of A Wireless Bat-Mounted Sonar Recording System, Jeremy Joseph Langford

Masters Theses

Scientists studying the behavior of bats monitor their echolocation calls, as their calls are important for navigation and feeding, but scientist are typically restricted to ground-based recording. Recording bat calls used for echolocation from the back of the bat as opposed to the ground offers the opportunity to study bat echolocation from a vantage otherwise only offered to the bats themselves. However, designing a bat mounted in-flight audio recording system, (bat-tag), capable of recording the ultra-sound used in bat echolocation presents a unique set of challenges. Chiefly, the bat-tag must be sufficiently light weight as to not overburden the bat, …

Review And Characterization Of Gallium Nitride Power Devices, Edward Andrew Jones

Masters Theses

Gallium Nitride (GaN) power devices are an emerging technology that have only recently become available commercially. This new technology enables the design of converters at higher frequencies and efficiencies than those achievable with conventional Si devices. This thesis reviews the characteristics and commercial status of both vertical and lateral GaN power devices from the user perspective, providing the background necessary to understand the significance of these recent developments. Additionally, the challenges encountered in GaN-based converter design are considered, such as the consequences of faster switching on gate driver design and board layout. Other issues include the unique reverse conduction behavior, …

Sic Band Gap Voltage Reference For Space Applications, Charles Kenneth Roberts

Masters Theses

Electronics for space applications can experience wide temperature swings depending on orientation towards stars and duty cycle of propulsion systems. Energy on satellites primarily comes from radiological thermal generators and / or solar panels. This requires space electronic applications to be energy efficient and have high temperature tolerance. As a result, space electronic systems use high efficiency SMPS [switching mode power supplies].

Currently, there exists SiC [silicon carbide] based electronics that is state of the art for high temperature applications. Commercial manufacturers at this time produce SiC Power MOSFETs [Metal Oxide Semiconductor Field Effect Transistors], which are the switching element …

Dividing And Conquering Meshes Within The Nist Fire Dynamics Simulator (Fds) On Multicore Computing Systems, Donald Charles Collins

Masters Theses

The National Institute for Standards and Technology (NIST) Fire Dynamics Simulator (FDS) provides a computational fluid dynamics model of a fire, which can be visualized by using NIST Smokeview (SMV). Users must create a configuration file (*.fds) that describes the environment and other characteristics of the fire scene so that the FDS software can produce the output file (*.smv) needed for visualization.The processing can be computationally intensive, often taking between several minutes and several hours to complete. In many cases, a user will create a file that is not optimized for a multicore computing system. By dividing meshes within the …

Implementation Of A Neuromorphic Development Platform With Danna, Jason Yen-Shen Chan

Masters Theses

Neuromorphic computing is the use of artificial neural networks to solve complex problems. The specialized computing field has been growing in interest during the past few years. Specialized hardware that function as neural networks can be utilized to solve specific problems unsuited for traditional computing architectures such as pattern classification and image recognition. However, these hardware platforms have neural network structures that are static, being limited to only perform a specific application, and cannot be used for other tasks. In this paper, the feasibility of a development platform utilizing a dynamic artificial neural network for researchers is discussed.

A Low-Power, Laser-Based Delta-Sigma Modulator For The Measurement Of Atmospheric Gas Composition, Christopher Edward Crowder

Masters Theses

With the increased attention on monitoring the atmosphere’s gas composition, new ways of accurately measuring these concentrations are needed. Along with the needed increase in measurement accuracy; size, space, and power reduction is also essential in modern systems. As semiconductor technology has advanced, the abilities to meet the previously mentioned criteria are becoming more realizable.

Instrumentation used to measure the atmosphere’s composition is traditionally large, taking up much needed space and using larger amounts of power. While the larger instrumentation provides the necessary accuracy, the other constraints are sacrificed. For this reason, a smaller, yet highly accurate solution is needed. …

Cmos Current-Frequency Signal Processing Unit For Bioimplantable Sensors, Madeline Nicole Threatt

Masters Theses

Over the past few decades, implantable monitoring of glucose, lactate acid, and pH monitoring has become a viable replacement for stationary monitoring. Implantable biosensing requires biosensors in conjunction with corresponding potentiostats and a signal processing unit to translate the data information to a more versatile, transmittable form. This thesis presents a current-mode signal processing unit (SPU) that merges the simplicity of a charging capacitor in feedback topology with the accuracy of a delta-sigma modulator to create a pulse train with a frequency proportional to the input current. The SPU was realized in a 0.18 µ[micro]m bulk CMOS process.

Radiation-Hardened Data Acquisition System Based On A Mask-Programmable Analog Array, Jacob Hunter Shelton

Masters Theses

Data acquisition systems capable of extreme temperature and radiation environments are of dire need in an era of great nuclear energy generation. Efforts to respond to recent nuclear accidents, such as those caused by natural disasters at Fukushima, have suffered in promptness and effectiveness due to the lack of information gathered from these sites. Currently, there are no systems available that accurately acquire, digitize, and remotely report this data in the presence of harsh radiation.

Using a mask-programmable analog array prototype chip designed for Triad Semiconductor and an FMI frequency synthesizer, both verified to beyond 300 kRad and 125ºC and …

Ultra-Low-Power Configurable Analog Signal Processor For Wireless Sensors, James Kelly Griffin

Masters Theses

The demand for on-chip low-power Complementary Metal Oxide Semiconductor (CMOS) analog signal processing has significantly increased in recent years. Digital signal processors continue to shrink in size as transistors half in size every two years. However, digital signal processors (DSP's) notoriously use more power than analog signal processors (APS's). This thesis presents a configurable analog signal processor (CASP) used for wireless sensors. This CASP contains a multitude of processing blocks include the following: low pass filter (LPF), high pass filter (HPF) integrator, differentiator, operational transconductance amplifier (OTA), rectifier with absolute value functionality, and multiplier. Each block uses current-mode processing and …

Digital-To-Analog Converter Interface For Computer Assisted Biologically Inspired Systems, Nicholas Conley Poore

Masters Theses

In today's integrated circuit technology, system interfaces play an important role of enabling fast, reliable data communications. A key feature of this work is the exploration and development of ultra-low power data converters. Data converters are present in some form in almost all mixed-signal systems; in particular, digital-to-analog converters present the opportunity for digitally controlled analog signal sources. Such signal sources are used in a variety of applications such as neuromorphic systems and analog signal processing. Multi-dimensional systems, such as biologically inspired neuromorphic systems, require vectors of analog signals. To use a microprocessor to control these analog systems, we must …

Microgrid Modeling And Grid Interconnection Studies, Hira Amna Saleem

Masters Theses

The demand for renewable energies and their integration to the grid has become more pressing than ever before due to the various reasons including increasing population energy demand, depleting fossil fuels, increasing atmospheric population, etc. Thus the vision of a sustainable future requires easy and reliable integration of renewable distributed generators to the grid. This master’s thesis studies the dynamics of distributed generators when they are connected with the main grid. Simulink MATLAB is used for the design and simulations of this system. Three distributed generators are used in this system: Photo-voltaic converter, Fuel cell and diesel generator. The control …

An On-Chip Transformer-Based Digital Isolator System, Cory Lynn Fandrich

Masters Theses

An on-chip transformer-based digital isolator has been designed, fabricated, and tested. This isolation technique is designed to function between a low voltage microcontroller and a potentially high-voltage power control system. The isolator’s isolation capability is determined by two factors, the RMS blocking voltage strength and common-mode transient immunity. The integrated circuit solution is designed in a high-temperature capable SOI process.

The on-chip transformer size is minimized by utilizing high frequency voltage pulses. A small transformer and overall small chip footprint of the design are favorable for integration into a larger system. The isolator is a two chip solution, an isolated …