A GaN-Based Synchronous Rectifier with Reduced Voltage Distortion for 6.78 MHz Wireless Power Applications

The call for a larger degree of engineering innovation grows as wireless power transfer increases in popularity. In this thesis, 6.78 MHz resonant wireless power transfer is explained. Challenges in WPT such as dynamic load variation and electromagnetic interference due to harmonic distortion are discussed, and a literature review is conducted to convey how the current state of the art is addressing these challenges.A GaN-based synchronous rectifier is proposed as a viable solution, and a model of the circuit is constructed. The precisely derived model is compared to a linearized model to illustrate the importance of exactness within the model derivation. The model is then used to quantify the design space of circuit parameters Lr and Cr with regard to harmonic distortion, input phase control, and efficiency. Practical design decisions concerning the 6.78 MHz system are explained. These include gate driver choice and mitigation of PCB parasitics. The model is verified with open loop experimentation using a linear power amplifier, FPGA, electronic load, and two function generators. Current zero-crossing sensing is then introduced in order to achieve self-regulation of both the switching frequency and input phase. The details of the FPGA code and sensing scheme used to obtain this closed loop functionality are described in detail. Finally, conclusions are drawn, and future work is identified

Implementation of Power Clock Generation Method for Pass-Transistor Adiabatic Logic 4:1 MUX

we proposed a sinusoidal single phase power clock generation method for 4:1 MUX which is designed in adiabatic logic form. For the power clock generation we presented radio frequency (3 KHz to 3 GHz) DC-AC converter. We have also obtained square wave from RC square wave oscillator consisting of cascaded NOT gates. This square wave and its inverted and phase shifted version are used as gate-drive signals for MOSFET switches those are used in the LC sine wave resonant circuit. The obtained power clock is then applied to a 4:1 MUX which is implemented in Pass-transistor Adiabatic Logic (PAL) style to illustrate power saving. It is observed that PAL 4:1 MUX is about 2 times more power efficient than that of conventional CMOS 4:1 MUX. If for 4:1 MUX, PAL logic is implemented in place of conventional CMOS logic, power saving per MUX that is achieved is about 47%. A 1 µm technology with ml2_20 as library is used for obtaining simulation results. DOI: 10.17762/ijritcc2321-8169.15060

Development of reliability methodology for systems engineering. Volume II - Application - Design reliability analysis of a 250 volt-ampere static inverter Final report

Design stage reliability analysis application to static inverte

Research on low power technology by AC power supply circuits

制度:新 ; 報告番号:甲3692号 ; 学位の種類:博士(工学) ; 授与年月日:2012/9/15 ; 早大学位記番号:新6060Waseda Universit

Power Reductions with Energy Recovery Using Resonant Topologies

The problem of power densities in system-on-chips (SoCs) and processors has become more exacerbated recently, resulting in high cooling costs and reliability issues. One of the largest components of power consumption is the low skew clock distribution network (CDN), driving large load capacitance. This can consume as much as 70% of the total dynamic power that is lost as heat, needing elaborate sensing and cooling mechanisms. To mitigate this, resonant clocking has been utilized in several applications over the past decade. An improved energy recovering reconfigurable generalized series resonance (GSR) solution with all the critical support circuitry is developed in this work. This LC resonant clock driver is shown to save about 50% driver power (\u3e40% overall), on a 22nm process node and has 50% less skew than a non-resonant driver at 2GHz. It can operate down to 0.2GHz to support other energy savings techniques like dynamic voltage and frequency scaling (DVFS). As an example, GSR can be configured for the simpler pulse series resonance (PSR) operation to enable further power saving for double data rate (DDR) applications, by using de-skewing latches instead of flip-flop banks. A PSR based subsystem for 40% savings in clocking power with 40% driver active area reduction xii is demonstrated. This new resonant driver generates tracking pulses at each transition of clock for dual edge operation across DVFS. PSR clocking is designed to drive explicit-pulsed latches with negative setup time. Simulations using 45nm IBM/PTM device and interconnect technology models, clocking 1024 flip-flops show the reductions, compared to non-resonant clocking. DVFS range from 2GHz/1.3V to 200MHz/0.5V is obtained. The PSR frequency is set \u3e3× the clock rate, needing only 1/10th the inductance of prior-art LC resonance schemes. The skew reductions are achieved without needing to increase the interconnect widths owing to negative set-up times. Applications in data circuits are shown as well with a 90nm example. Parallel resonant and split-driver non-resonant configurations as well are derived from GSR. Tradeoffs in timing performance versus power, based on theoretical analysis, are compared for the first time and verified. This enables synthesis of an optimal topology for a given application from the GSR

Improving Power Leveling Range Of Microwave Signal Source Using Dual-Slope Logarithmic Amplifier [TK7872.S5 L863 2007 f rb].

Penjana atau sumber isyarat adalah penting untuk sebarang pengukuran yang memerlukan isyarat masukan sebagai perangsang. Beberapa sifat penjana isyarat yang penting adalah termasuk kejituan frekuensi dan kuasa keluaran. Signal generator or source is essential to any measurements requiring an input signal as stimulant. Some of the important characteristics of a signal generator include frequency and output power accuracy

A laboratory and field study of the attenuation of sound intensity using a whistle as the sonic generator

This study investigated the attenuation of sound intensity using a whistle as the sonic generator along with the detailed analysis of all the previous studies. Attenuation of sound in air studies were performed in Otto H. York Center for Environmental Engineering and Science at New Jersey Institute of Technology. Sound attenuation through air was measured by doubling the distance for each of five whistles. It was concluded that Whistle No.5 gives the highest sound intensity of 140.54 dB at a distance of 0.75 ft , the closest distance used for measurement, at a air flow rate of 7.5 SCFM. These data were extrapolated to within one-inch of the whistle and the sound intensity at this distance was about an average of 160.7 dB. The data of sound intensity in decibels versus distance in feet were curve fit using the best-fit curve, Power Equation. It was also concluded that a single whistle produces high sound intensities in comparison to the combination of two whistles.This study investigates the recommendations of previous studies for re-conducting the attenuation of sound focused in an artificial fracture. Previous studies by Zarnetske and Godde recommended that the Bootwala, 2000 field study should be re-conducted with the position of the microphone directed into the fracture using Whistle No. 5. This study has developed the complete procedure and methodology to conduct the above studies in the field. Previous studies should be expanded to give more knowledge from controlled laboratory tests. The work should be expanded to include soil, in addition, to the porous rock slab