A Highly Integrated GaAs-based Module for DC-DC Regulators

2013 ◽  
Vol 2013 (1) ◽  
pp. 000604-000610 ◽  
Author(s):  
Greg J. Miller

There is a need and desire to push low voltage point-of-load voltage regulators (POL VRs) to higher switching frequencies. The main reason for this is to increase power density. Silicon MOSFET-based solutions are rapidly approaching their technology limits and are not capable of providing multi-MHz switching frequency for high current (>10A) applications. Gallium Arsenide (GaAs) field effect transistors (FETs) can switch much faster, enabling cost-effective, high-current, high switching frequency POL VRs. Recent advances in GaAs technologies have enabled the demonstration of 5MHz VRs and provide a path to even higher frequency (>50MHz) Power Supply in Package (PSiP) solutions. The high-speed GaAs power FETs are the “engine” to enable efficient high switching frequency POL VRs, but certain key elements must be designed appropriately to realize the desired performance. The gate driver and power path impedances must be minimized. To do this, a high level of integration is required, thus packaging is a critical element. New embedded die packaging solutions enable this high level of integration, dramatically reducing key parasitic impedances that can otherwise throttle performance, while also facilitating very compact multi-chip modules.

Energies ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 4144
Author(s):  
Yatai Ji ◽  
Paolo Giangrande ◽  
Vincenzo Madonna ◽  
Weiduo Zhao ◽  
Michael Galea

Transportation electrification has kept pushing low-voltage inverter-fed electrical machines to reach a higher power density while guaranteeing appropriate reliability levels. Methods commonly adopted to boost power density (i.e., higher current density, faster switching frequency for high speed, and higher DC link voltage) will unavoidably increase the stress to the insulation system which leads to a decrease in reliability. Thus, a trade-off is required between power density and reliability during the machine design. Currently, it is a challenging task to evaluate reliability during the design stage and the over-engineering approach is applied. To solve this problem, physics of failure (POF) is introduced and its feasibility for electrical machine (EM) design is discussed through reviewing past work on insulation investigation. Then the special focus is given to partial discharge (PD) whose occurrence means the end-of-life of low-voltage EMs. The PD-free design methodology based on understanding the physics of PD is presented to substitute the over-engineering approach. Finally, a comprehensive reliability-oriented design (ROD) approach adopting POF and PD-free design strategy is given as a potential solution for reliable and high-performance inverter-fed low-voltage EM design.


Energies ◽  
2021 ◽  
Vol 14 (6) ◽  
pp. 1738
Author(s):  
Vanessa Neves Höpner ◽  
Volmir Eugênio Wilhelm

The use of static frequency converters, which have a high switching frequency, generates voltage pulses with a high rate of change over time. In combination with cable and motor impedance, this generates repetitive overvoltage at the motor terminals, influencing the occurrence of partial discharges between conductors, causing degradation of the insulation of electric motors. Understanding the effects resulting from the frequency converter–electric motor interaction is essential for developing and implementing insulation systems with characteristics that support the most diverse applications, have an operating life under economically viable conditions, and promote energy efficiency. With this objective, a search was carried out in three recognized databases. Duplicate articles were eliminated, resulting in 1069 articles, which were systematically categorized and reviewed, resulting in 481 articles discussing the causes of degradation in the insulation of electric motors powered by frequency converters. A bibliographic portfolio was built and evaluated, with 230 articles that present results on the factors that can be used in estimating the life span of electric motor insulation. In this structure, the historical evolution of the collected information, the authors who conducted the most research on the theme, and the relevance of the knowledge presented in the works were considered.


2020 ◽  
Vol 10 (19) ◽  
pp. 6656
Author(s):  
Stefano Lai ◽  
Giulia Casula ◽  
Pier Carlo Ricci ◽  
Piero Cosseddu ◽  
Annalisa Bonfiglio

The development of electronic devices with enhanced properties of transparency and conformability is of high interest for the development of novel applications in the field of bioelectronics and biomedical sensing. Here, a fabrication process for all organic Organic Field-Effect Transistors (OFETs) by means of large-area, cost-effective techniques such as inkjet printing and chemical vapor deposition is reported. The fabricated device can operate at low voltages (as high as 4 V) with ideal electronic characteristics, including low threshold voltage, relatively high mobility and low subthreshold voltages. The employment of organic materials such as Parylene C, PEDOT:PSS and 6,13-Bis(triisopropylsilylethynyl)pentacene (TIPS pentacene) helps to obtain highly transparent transistors, with a relative transmittance exceeding 80%. Interestingly enough, the proposed process can be reliably employed for OFET fabrication over different kind of substrates, ranging from transparent, flexible but relatively thick polyethylene terephthalate (PET) substrates to transparent, 700-nm-thick, compliant Parylene C films. OFETs fabricated on such sub-micrometrical substrates maintain their functionality after being transferred onto complex surfaces, such as human skin and wearable items. To this aim, the electrical and electromechanical stability of proposed devices will be discussed.


2011 ◽  
Vol 2011 (HITEN) ◽  
pp. 000152-000158
Author(s):  
J. Valle Mayorga ◽  
C. Gutshall ◽  
K. Phan ◽  
I. Escorcia ◽  
H. A. Mantooth ◽  
...  

SiC power semiconductors have the capability of greatly outperforming Si-based power devices. Faster switching and smaller on-state losses coupled with higher voltage blocking and temperature capabilities, make SiC a very attractive semiconductor for high performance, high power density power modules. However, the temperature capabilities and increased power density are fully utilized only when the gate driver is placed next to the SiC devices. This requires the gate driver to successfully operate under these extreme conditions with reduced or no heat sinking requirements, allowing the full realization of a high efficiency, high power density SiC power module. In addition, since SiC devices are usually connected in a half or full bridge configuration, the gate driver should provide electrical isolation between the high and low voltage sections of the driver itself. This paper presents a 225 degrees Celsius operable, Silicon-On-Insulator (SOI) high voltage isolated gate driver IC for SiC devices. The IC was designed and fabricated in a 1 μm, partially depleted, CMOS process. The presented gate driver consists of a primary and a secondary side which are electrically isolated by the use of a transformer. The gate driver IC has been tested at a switching frequency of 200 kHz at 225 degrees Celsius while exhibiting a dv/dt noise immunity of at least 45 kV/μs.


Author(s):  
Shaun E. Koktavy ◽  
Alexander C. Yudell ◽  
James D. Van de Ven

A challenge in realizing switch-mode hydraulic circuits is the need for a high-speed valve with fast transition time and high switching frequency. The work presented includes the design and modeling of a suitable valve and experimental demonstration of the prototype in a hydraulic boost converter. The design consists of two spools driven by crank-sliders, designed for 120 Hz maximum switching frequency at a flow rate of 22.7 lpm. The fully open throttling loss is designed for <2% of the rated pressure of 34.5 MPa. The transition time is less than 5% (0.42 ms at 120 Hz) of the total cycle and the duty cycle is adjustable from 0 to 1. Leakage and viscous friction losses in the design are less than 2% of the rated hydraulic energy per cycle. The experimental results agreed well with the model resulting in a 3% variation in transition time. The use of the high-speed valve in a pressure boosts converter demonstrated boost ratio capabilities of 1.08–2.06.


2012 ◽  
Vol 23 (14) ◽  
pp. 1750-1758 ◽  
Author(s):  
Babak Nasr ◽  
Di Wang ◽  
Robert Kruk ◽  
Harald Rösner ◽  
Horst Hahn ◽  
...  

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