Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 20 of 27 for “"VRMs"”.
-
Modeling and Design of Digitially Controlled Voltage Regulator Modules
… and high frequency voltage regulator modules (VRMs) where conventional analog controllers are currently preferred because of the cost and performace reasons. However, there are still remaining two significant challenges for the spread of the digital control techniques: quantization effects and …
-
Multiphase Voltage Regulator Modules with Magnetic Integration to Power Microprocessors
… high-power-density and fast-transient VRMs. The optimization of multiphase VRMs has also been addressed. Today's multiphase VRMs are almost universally based on the buck topology. With increased input voltage and decreased output voltage, the multiphase buck converter suffers from a …
-
Studying 3D Spherical Shell Convection using ASPECT
… of the root mean square velocity (Vrms) and Nusselt number agree, often to within 1%. The 3D cases come from Zhong et al. (2008). Modifications were made to the simple.cc and harmonic_perturbation.cc files in the ASPECT code in order to reproduce the initial conditions and …
-
Supercapacitor-based linear converter for voltage regulator modules
… for microprocessor voltage regulator modules (VRMs). The original linear regulator is the patented supercapacitor assisted low-dropout regulator (SCALDO). A less complex, lower cost design was achieved by reducing the number of switches in the original SCALDO and adding a second low dropout …
-
Low-voltage High-efficiency Fast-transient Voltage regulator Module
… power supplies and Voltage Regulator Modules (VRMs) to provide lower voltages with higher currents and fast transient capabilities for microprocessors. This work presents several low-voltage high-current VRM technologies for future generation data processing, communication, and portable …
-
An ultra-low-power neural recording amplifier and its use in adaptively-biased multi-amplifier arrays
… input-referred noise was measured to be 3.06 [mu]Vrms, while consuming 7.56 [mu]W of power from a 2.8 V supply corresponding to a Noise Efficiency Factor (NEF) of 2.67 with the theoretical limit being 2.02. When configured for recording LFPs, the amplifier achieved a midband gain of 40.9 dB and a …
-
Power factor correction using a boost quasi-resonant converter
… at a maximum of 1 megahertz, with a 115 VRMS input, 200 VDC and 100 watt output.
-
48V/1V Voltage Regulator for High-Performance Microprocessors
… lies in the voltage regulator modules (VRMs), which grapple with challenges such as high conversion ratios, elevated output currents, and substantial load transients. These challenges are particularly pronounced for AI processors and graphics processing units (GPUs), given their …
-
A stacked full-bridge microinverter topology for photovoltaic applications
… the resonant current into a single-phase 240 VRMS utility line. This thesis presents a new stacked full-bridge topology that improves upon the previous high-frequency inverter section. By utilizing new operating modes to reduce the reliance on frequency control and allowing for the use of …
-
Acoustic assisted actuation of Ni-Mn-Ga ferromagnetic shape memory alloys
… 21% for a piezoelectric driven at 5 kHz and 20 Vrms. As a result of this large threshold reduction, strain output can be more than doubled for magnetic drive amplitudes near the threshold field.
-
The charge migration in biomolecules
… in the band conduction, it is estimated that vrms = 10 to the 6th ~10 to the 7th cm/sec. The probability of finding the access charge at n unit cells away from the initial place is Pn = |Jn (2Bt/h)|2 where is the Bessel function of first kind and of order n. The effects neglected in this …
-
Investigation of High-Input-Voltage Non-Isolated Voltage Regulator Modules Topology Candidates
… and it is therefore a good candidate for 12V VRMs.
-
Amplifier and data converter techniques for low power sensor interfaces
… (PEF) of 1.6 with an input noise of 0.94 [mu]VRMS, integrated from 0.5 to 670 Hz. Human biopotential signals are measured using the AFE.
-
Modeling and Characterization of Power Electronic Converters with an Integrated Transmission-Line Filter
… kHz, with a universal input ranging from 90-270 VRMS with unity power factor. The time-domain and EMI frequency spectrum waveforms are experimentally measured and agree very well with the simulated values; within 5 dB for EMI. The transmission-line filter was also manufactured for model …
-
Digital control of a multi-channel boundary-conduction-mode boost converter for power-factor-correction applications
… over the universal line-voltage range from 85 Vrms to 265 Vrms. Secondly, the output voltage of PFC rectifiers contains a 2nd harmonic ripple which can be fed into the control loop and distort the line current. In this work, an adaptive notch filter which works over a range of line frequencies, …
-
Harmonic reduction of a single-phase multilevel inverter using genetic algorithm and particle swarm optimization
… (9.27%) and fundamental component voltage (240 Vrms). The research proceed with optimization with fundamental switching frequency method that is optimized harmonic stepped waveform modulation method. The selective harmonics elimination calculation have adapt with genetic algorithm and particle …
-
Long-term, subdermal implantable EEG recording and seizure detection
… an input-referred noise of approximately 1.1 [mu]Vrms. The seizure detection algorithm has a sensitivity of 98.5%, a false alarm rate of 4.4 per hour, and a detection delay of 9.1 seconds. It consumes only 0.45 [mu]W, which is over an order of magnitude less power than comparable algorithms.
-
Tunable Liquid Crystal Photonic Devices
… sizes, the operating voltage is higher than 100 Vrms. To lower the driving voltage, in Chap. 2 and Chap. 3, we have investigated a polymer-network liquid crystal (PNLC) using a rod-like monomer structure. Since the monomer concentration is only about 5%, the operating voltage is below 10 Vrms. …
-
Liquid Crystal Materials And Tunable Devices For Optical Communications
… is realized with over 30 dB attenuation, ~12 Vrms drive voltage and 11/28 milliseconds (rise/decay) response times. A polymer-stabilized twisted nematic LC (PS TNLC) is also proposed as a variable optical attenuator for optical communications. By using the polarization control system, the …
-
Performance Improvements of Multi-Channel Interleaving Voltage Regulator Modules with Integrated Coupling Inductors
… is the most popular topology for present VRMs. Analysis in this work shows that the small-signal model of an n-channel interleaving buck can be simplified as a single buck converter. The equivalent inductance is 1/n of the inductance in the interleaving channel. The equivalent switching …
Page 1 of 2