Limiters Protect Adcs Without Adding Harmonics, 2015 Avago Technologies, Malaysia
Limiters Protect Adcs Without Adding Harmonics, Chin-Leong Lim
High-speed Analogue to Digital Converters (ADC) are used for sampling at either the intermediate frequency (IF) or the radio frequency of wireless receivers. When the transmitter is nearby, the sampled signal can exceed the ADC’s maximum input level. So, amplitude limiting is necessary to prevent ADC damage or degradation. While automatic gain control is effective for controlling IF amplitude excursion in traditional single-carrier systems, it is not desirable in modern multi-carrier applications. One solution is to cap the IF amplitude excursion with a limiter. Unfortunately, a new problem is created – the strong non-linearity that is required of a good ...
Lna Integrates Fast Shutdown Function, 2014 Avago Technologies, Malaysia
Lna Integrates Fast Shutdown Function, Chin-Leong Lim
To minimize dead time in time domain duplex (TDD) transceiver, reception should ideally commence as soon as transmission ends. However, the low noise amplifier (LNA), which is typically shutdown during transmission to prevent device damage and receiver overload, can exhibit a turn-on delay. In older implementations, the shutdown function is external to the LNA device. So, one way to reduce part count and to miniaturize this class of LNA is to integrate the LNA and shutdown function in a microwave monolithic integrated circuit (MMIC). The integration also allows the shutdown circuit to be connected to the LNA at an optimum ...
Buck Converter, 2014 California Polytechnic State University - San Luis Obispo
Buck Converter, Bowen Liu
The recent sustainable energy growth triggered a huge power electronics demand, specifically related to power conversion. My senior project is a design of a buck converter which steps down the voltage from photovoltaic cells ranging from 5 to 40V to a rechargeable battery with 5V. This converter has a high enough power efficiency to effectively convert the energy harnessed from PV panels.
Energy Harvesting From Exercise Machines: Lt8705 Dc-Dc Conversion For Elliptical Trainers, 2014 California Polytechnic State University - San Luis Obispo
Energy Harvesting From Exercise Machines: Lt8705 Dc-Dc Conversion For Elliptical Trainers, Braden Burk, Raj Bhula, Nathan Mckay
Cal Poly’s Energy Harvesting from Exercise Machines (EHFEM) program aims to power the grid using human energy harvested from exercise machines in its gym. Doing so could save the school money and increase the total supply of power available on the grid. This document belongs to one of many groups attempting to design a suitable DC-DC conversion system for an elliptical trainer using an LT8705 Four-Switch Buck-Boost converter. Past teams have built other converters and developed system compatibility characteristics such as filtering, safety, and stability for interfacing components. These teams fall into one of two departments in EHFEM: DC-DC ...
A Low-Power Approach For Front End Biological Signal Conditioning, 2014 University of Tennessee - Knoxville
A Low-Power Approach For Front End Biological Signal Conditioning, Logan Smith Taylor
In a lab-on-a-chip (LOC) application, the measurement of small analog signals such as local temperature variation often involves detection of very low-level signals in a noisy micro-scale environment. This is true for other biomedical monitoring systems as well. These systems observe various physiological parameters or electrochemical reactions that need to be tracked electrically. For temperature measurement pyroelectric transducers represent an efficient solution in terms of speed, sensitivity, and scale of integration, especially when prompt and accurate temperature monitoring is desired.
The ability to perform laboratory operations on a small scale using miniaturized LOC devices is a promising biosensing technique. The ...
Development And Modeling Of A Biosensor Platform Using Algan/Gan Hemt Devices, 2014 University of Tennessee - Knoxville
Development And Modeling Of A Biosensor Platform Using Algan/Gan Hemt Devices, Fahmida Shaheen Tulip
The history of biosensors began in 1962 with the invention of enzyme electrodes by Leland C. Clark. Since then, biosensors have come a long way with simultaneous contributions in various fields such as biology, chemistry, material science, electronics, physics and VLSI. With the advancement in science and technology, smaller, more sensitive and dependable biosensors have become a reality. Still the need for cost-effective, sophisticated, reliable, robust biosensors that can be used to detect multiple types of biomolecules remains a technological challenge to be resolved.
The proposed AlGaN/GaN High Electron Mobility Transistors (HEMTs) have excellent prospect to become the biosensor ...
A Fast-Converging Mppt Technique For Photovoltaic System Under Fast Varying Solar Irradiation And Load Resistance, 2014 Department Of Electrical Engineering
A Fast-Converging Mppt Technique For Photovoltaic System Under Fast Varying Solar Irradiation And Load Resistance, Saad Mekhilef
Under fast varying solar irradiation and load resistance, a fast-converging maximum power point tracking system is required to ensure the photovoltaic system response rapidly with minimum power losses. Traditionally, maximum power point locus was used to provide such a fast response. However, the algorithm requires extra control loop or intermittent disconnection of the PV module. Hence, this paper proposes a simpler fast-converging maximum power point tracking technique, which excludes the extra control loop and intermittent disconnection. In the proposed algorithm, the relationship between the load line and the I–V curve is used with trigonometry rule to obtain the fast ...
Implications Of Rough Dielectric Surfaces On Charging-Adjusted Actuation Of Rf-Mems, 2014 Purdue University
Implications Of Rough Dielectric Surfaces On Charging-Adjusted Actuation Of Rf-Mems, Sambit Palit, Xin Xu, Arvind Raman, Muhammad Ashraful Alam
Birck and NCN Publications
Actuation voltage shifts due to dielectric charging is a leading reliability concern in Radio-Frequency Micro-Electro-Mechanical Systems (RF-MEMS) capacitive switches. The inability to correlate dielectric surface roughness to charge accumulation makes predictive design difficult. We apply a sophisticated dielectric charging model on representative surfaces based on Atomic Force Microscopy (AFM) data, and show that there are significant, but predictable actuation voltage shifts due to surface roughness. The results suggest that surface roughness should be considered for accurate lifetime predictions, and simple metal-insulator-metal (MIM) capacitors may serve as a useful test structure for this phenomenon.
Hybrid Silicon Mode-Locked Laser With Improved Rf Power By Impedance Matching, 2014 California Polytechnic State University - San Luis Obispo
Hybrid Silicon Mode-Locked Laser With Improved Rf Power By Impedance Matching, Bassem M. Tossoun
Master's Theses and Project Reports
The mode-locked laser diode (MLLD) finds a lot of use in applications such as ultra high-speed data processing and sampling, large-capacity optical fiber communications based on optical time-division multiplexing (OTDM) systems. Integrating mode-locked lasers on silicon makes way for highly integrated silicon based photonic communication devices. The mode-locked laser being used in this thesis was built with Hybrid Silicon technology. This technology, developed by UC Santa Barbara in 2006, introduced the idea of wafer bonding a crystalline III- V layer to a Silicon-on-insulator (SOI) substrate, making integrated lasers in silicon chips possible.
Furthermore, all mode-locked lasers produce phase noise, which ...
Health Risks Caused By Wireless Technologies, 2014 Minnesota State University, Mankato
Health Risks Caused By Wireless Technologies, Durreeshahwar Zafarahmed, Qurrat-Ul-Ain Zafarahmed
Journal of Undergraduate Research at Minnesota State University, Mankato
There are many health issues related to the use of cellular phones, wireless local area networks, and other devices that emit electromagnetic radiation (EMR). Some of these systems have become a part of our daily lives and many of us are in direct or indirect contact for extended period of times with these devices. However, the general public is unaware of the health risks associated with the use of these devices. Our research covers studies done by individuals as well as organizations on the harmful effects on the health of people from these devices and their claims. We also present ...
Polymer-Based Thermoelectric Devices, 2014 Purdue University
Polymer-Based Thermoelectric Devices, Stuart W. Hilsmier, Edward P. Tomlinson, Bryan Boudouris
The Summer Undergraduate Research Fellowship (SURF) Symposium
Currently, over 50% of all energy generated in the US is lost as waste heat, and thermoelectric generators offer a promising means to recoup some of this energy, if their efficiency is improved. While organic thermoelectric materials lack the efficiency of their inorganic counterparts, they are composed of highly abundant resources and have low temperature processing conditions. Recently, a new class of redox-active polymers, radical polymers, has exhibited high electrical conductivity in an entirely amorphous medium. In addition, these radical polymers have a simple synthetic scheme and can be highly tunable to provide desired electrical properties. In this study, the ...
Developing Compact Models For Passive Devices On Ibm 45nm Cmos Soi Technology, 2014 Purdue University
Developing Compact Models For Passive Devices On Ibm 45nm Cmos Soi Technology, Yufei Feng, Yanfei Shen, Saeed Mohammadi
The Summer Undergraduate Research Fellowship (SURF) Symposium
The standard IBM 45 nm technology is widely adopted for industrial and academic purpose by integrates circuit designers. Original models provided by foundry are not accurate, which might cause inaccuracy in circuit simulations. Equivalent circuit models, using RLC elements to simulate electrical component, will effectively deliver their electrical performance. This study consists of four steps to construct these models. First, Cadence Virtuoso, the commercial circuit design software was used to run simulations and extract data for different device parameters. Second, analyzing tools, like Microsoft Excel or Matlab, are used to analyze the extracted data. Then, equations are written for each ...
Wave-Shaped Mask Of Fabricating Nano-Scaled Structure, 2014 National Taiwan University
Wave-Shaped Mask Of Fabricating Nano-Scaled Structure, Fang-Tzu Chuang
A wave-shaped mask for fabricating a nano-scale structure is disclosed. The wave-shaped mask comprises an elastomeric transparent substrate having an upper surface and a lower surface, and a light-penetrable thin film layer disposed on the upper surface of the elastomeric transparent substrate. The upper surface of the elastomeric transparent substrate and the light-penetrable thin film layer are in a periodic wave shape, and the lower surface of the elastomeric transparent substrate is in a plate shape.
Low Loss Configuration For Integrated Pin-Schottky Limiters, 2014 Avago Technologies, Malaysia
Low Loss Configuration For Integrated Pin-Schottky Limiters, Chin-Leong Lim
Compared to the PIN diode limiter, the Schottky-PIN limiter improves receiver protection, but has a higher insertion loss. Low cost, plastic packaged diodes can further worsen the loss. Diode stacking, mesa diode construction, and isolating the Schottky diode with a high-impedance quarter wave line or a directional coupler can reduce loss, but detrimentally raises the limiting threshold and/or adds bulk or cost. The PIN-Schottky limiter’s insertion loss can be improved by integrating the diodes’ parasitic capacitances into a low pass ladder network, but this solution requires the PIN diode to have two anode connections. Recently, the PIN-Schottky limiter ...
In-Line Microfluidic Particle Preconcentrator And Detector For Continuous Flow Monitoring, 2014 University of Tennessee - Knoxville
In-Line Microfluidic Particle Preconcentrator And Detector For Continuous Flow Monitoring, Quan Yuan
This dissertation presents the design and prototyping of three in-line microfluidic devices for continuous monitoring of particulate flows. The three devices are AC electrokinetic (ACEK) and acoustic sample preconcentration techniques for resettable particle enrichment, and an in-line somatic cell counter for mastitis monitoring.
For the ACEK preconcentrator, ACEK is a new and promising technique to manipulate micro/bio-fluid and particles. There are many advantages over other techniques, such as low applied voltage, low cost, portability and notable biocompatibility of lab-on-a-chip (LOC) device. We successfully developed a 3D multi-level electrode platform to extract bioparticles via AC electroosmosis (ACEO) and negative Dielectrophoresis ...
Characterization And Testing Of A 5.8 Kv Sic Pin Diode For Electric Space Propulsion Applications, 2014 University of Nebraska-Lincoln
Characterization And Testing Of A 5.8 Kv Sic Pin Diode For Electric Space Propulsion Applications, Alexandra Toftul
Electrical Engineering Theses and Dissertations
Inductive Pulsed Plasma Thrusters (IPPTs) are a type of in-space propulsion that has multiple advantages over conventional chemical propulsion for long-duration, deep space missions. Existing IPPT prototypes utilize spark gap switches, however these are subject to corrosion problems that make them unreliable for long-term use. Recent advances in solid state switching technology have opened up a variety of switching options that could provide greater reliability, controllability, and increased energy efficiency. Taking advantage of this, a novel thruster drive circuit topology containing a high-power silicon controlled rectifier (SCR) and series fast recovery diode (FRD) is proposed that is expected to increase ...
Novel Configuration For Multilevel Dc-Link Three-Phase Five-Level Inverter, 2014 Department Of Electrical Engineering
Novel Configuration For Multilevel Dc-Link Three-Phase Five-Level Inverter, Saad Mekhilef
new multilevel DC-link three-phase five-level voltage source inverter topology is introduced here. A multilevel DClink formed from single DC voltage supply and two cascaded half-bridge (CHB) power cells is connected to 12-switch threephase bridge in such a way that the proposed inverter produces five levels in the output voltage waveform. Compared to comparable inverters, such as symmetrical CHB and hybrid multilevel inverters, the proposed topology maximises the number of voltage levels and reduces the number of utilised DC voltage supplies, switches, gate driver circuits and installation area. A modified fundamental frequency modulation technique based on determination of switching states of ...
Method Of Fabricating Wave-Shaped Mask For Photolithography And Exposure Method Of Fabricating Nano-Scaled Structure Using The Wave-Shaped Mask, Fang-Tzu Chuang
A method of fabricating wave-shaped mask is disclosed. The method of fabricating wave-shaped mask comprises the steps of providing an elastomeric transparent substrate comprising an upper surface and a lower surface, applying a stable force to the elastomeric transparent substrate for deforming the elastomeric transparent substrate, forming a light-penetrable thin film layer on the upper surface of the elastomeric transparent substrate, and removing the force applying to the elastomeric transparent substrate, whereby the upper surface of the elastomeric transparent substrate and the light-penetrable thin film layer are in a periodic wave shape and the lower surface of the elastomeric transparent ...
Rapid Battery Exchange Safety And Sensing, 2014 California Polytechnic State University - San Luis Obispo
Rapid Battery Exchange Safety And Sensing, Ben John Froelich, Isaac Sungjin Kim
The Rapid Battery Exchange system (RBX) swaps batteries in an electric van, allowing almost continuous operation of the vehicle. The RBX system is designed and built by The Cal Poly Electric Vehicle Engineering Club (EVEC). The system includes the exchange ramp, two battery packs, and the electric “G-Van.” While the vehicle drives using one of the battery packs, the other pack charges in the exchange ramp. When the van’s battery depletes, it drives onto the ramp and swaps the dead battery for the charged one, and the process repeats.
The RBX battery pack safety and sensing project divides into ...
Low Voltage Cmos Sar Adc Design, 2014 California Polytechnic State University - San Luis Obispo
Low Voltage Cmos Sar Adc Design, Ryan Hunt
This project centers on the design of a single ended 10-bit successive approximation register analog to digital converter (SAR ADC for short) that easily interfaces to a micro-controller, such as an Arduino. With micro-controller interfacing in mind, the universal data transfer technique of SPI proved an easy way to communicate between the ADC and the micro-controller. The ADC has a range of 1V (highest code value) to 0V (lowest code value) and operates from a single voltage rail value of 1.8V. Typical SPI clock speeds run on the order of 2MHz and with a 10-bit ADC this means a ...