The Laser Microphone Authors: Mark Chounlakone, Julian Alverio Filtering Section: Justin Tunis
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UCC27531 35-V Gate Driver for Sic MOSFET Applications (Rev. A)
(1) Application Report SLUA770A–March 2016–Revised May 2018 UCC27531 35-V Gate Driver for SiC MOSFET Applications Richard Herring........................................................................................... High Power Driver Solutions ABSTRACT SiC MOSFETs are gaining popularity in many high-power applications due to their significant switching performance advantages. SiC MOSFETs are also available with attractive voltage ratings and current capabilities. However, the characteristics of SiC MOSFETs require consideration of the gate-driver circuit to optimize the switching performance of the SiC device. Although SiC MOSFETs are not difficult to drive properly, many typical MOSFET drivers may result in compromised switching speed performance. The UCC27531 gate driver includes features and has operating parameters that allow for driving SiC power MOSFETs within the recommended optimum drive configuration. This application note reviews the characteristics of SiC MOSFETs and how to drive them to achieve the performance improvement that SiC can bring at the system level. The features of UCC27531 to achieve optimal performance of SiC are explained and results from a demonstration circuit are provided. 1 Introduction In the past, the majority of applications such as uninterruptible power supplies (UPS), photovoltaic (PV) inverters, and motor drive have utilized IGBTs for the power devices due to the combination of high- voltage ratings exceeding 1 kV and high current capability. Usable switching frequency of IGBTs has typically been limited to 20–30 kHz, due to the high turnoff losses caused by the long turnoff current tail. Design comparisons have shown that SiC MOSFET designs can operate at considerably higher switching frequency and achieve the same or better efficiency. Although the device cost of the SiC MOSFETs are higher than the equivalent IGBTs, the significant savings in transformer, capacitor, and enclosure size results in a lower system cost. -
Egan® Ics for Low Voltage DC-DC Applications Egan® Ics for Low Voltage DC-DC Applications EFFICIENT POWER CONVERSION
APPLICATION NOTE: AN025 eGaN® ICs for Low Voltage DC-DC Applications eGaN® ICs for Low Voltage DC-DC Applications EFFICIENT POWER CONVERSION Michael de Rooij, Ph.D., Vice President of Applications Engineering , Yuanzhe Zhang, Ph.D., Director of Applications Engineering eGaN® FETs from EPC have repeatedly demonstrated higher performance over Monolithic integration of the gate driver to the MOSFET counterparts in many applications [1]. The lateral structure and material FET offers the lowest possible common source properties of eGaN FETs make it possible to monolithically integrate a number of FETs inductance (CSI) as it is moved to within the as demonstrated by products such as the EPC2107 [2]. The next phase in the eGaN IC structure. Furthermore the gate driver has been optimized for the FET being driven to offer FET and IC evolution includes gate driver integration. Integrating the gate driver with maximum performance under any operating the FET offers a number of additional advantages over discrete gate driver and FET condition. These benefits are on top of the well- solutions such as extremely low common source inductance, matched gate driver established low capacitance and inductance, and to FET, and ease of design. All the traditional eGaN FET benefits such as significantly zero reverse recovery charge (QRR) that enable lower capacitance and inductance with zero reverse recovery charge (QRR) in a smaller efficient operation at high switching frequencies even under hard switching conditions. The key footprint for a given on-resistance (RDS(on)) than comparable MOSFETs are retained. However, the combined effect of the new characteristics and benefits ensures an ever characteristics of the EPC2112 are given in table 1. -
Resonant Gate-Drive Circuits for High-Frequency Power Converters
Resonant Gate-Drive Circuits for High-Frequency Power Converters A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy By Hur Jedi B. S., University of Baghdad, Baghdad, Iraq, 2003 M. S., University Putra Malaysia, Selangor, Malaysia, 2010 2018 Wright State University WRIGHT STATE UNIVERSITY GRADUATE SCHOOL November 16, 2018 I HEREBY RECOMMEND THAT THE DISSERTATION PREPARED UNDER MY SUPERVISION BY Hur Jedi ENTITLED Resonant Gate-Drive Circuits for High-Frequency Power Converters BE ACCEPTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF Doctor of Philosophy. Marian K. Kazimierczuk, Ph.D. Dissertation Director Arnab Shaw, Ph.D. Director, Electrical Engineering Ph.D. Program Barry Milligan, Ph.D. Interim Dean of the Graduate School Committee on Final Examination Marian K. Kazimierczuk, Ph.D. Ray Siferd, Ph.D. Henry Chen, Ph.D. Saiyu Ren, Ph.D. Yan Zhuang, Ph.D. Abstract Jedi, Hur. Ph.D., Electrical Engineering Ph.D. Program, Department of Electrical Engineering, Wright State University, 2018. Resonant Gate-Drive Circuits for High- Frequency Power Converters. The development trend of power converters motivates the pursuit with high den- sity, high efficiency, and low cost. Increasing the frequency can improve the power density and lead to small passive elements and a fast dynamic response. Each one of these power converters must be driven by a gate-drive circuit to operate efficiently. Conventional gate-drivers are used up to frequencies of about 5 MHz and suffer from switching losses. Therefore, the development of switch-mode power supplies (SMPS) operating at high frequencies requires high-speed gate drivers. -
Igbts (Insulated Gate Bipolar Transistor) Application Note
IGBTs (Insulated Gate Bipolar Transistor) Application Note IGBTs (Insulated Gate Bipolar Transistor) Description This document describes the basic structures, ratings, and electrical characteristics of IGBTs. It also provides usage considerations for IGBTs. © 2018 1 2018-09-01 Toshiba Electronic Devices & Storage Corporation IGBTs (Insulated Gate Bipolar Transistor) Application Note Table of Contents Description ............................................................................................................................................ 1 Table of Contents ................................................................................................................................. 2 1. Device structure and characteristics of IGBTs ............................................................................. 6 1.1. Basic structure of the IGBT ................................................................................................................ 6 1.2. Comparison of different types of transistors (bipolar transistors, MOSFETs, and IGBTs) ....... 8 2. Different types of IGBTs and their structures ............................................................................ 11 2.1. Gating structures ................................................................................................................................11 2.2. IGBT classification based on the vertical structure ...................................................................... 12 2.2.1. Punch-through (PT) IGBTs ................................................................................................................12 -
And Passive Speakers?
To be active or not to be active – that is the question... To be active or not to be active – that is the question... 1. Active, passive – the situation 2. Active and passive loudspeaker – the basic difference 3. Passive loudspeaker 4. Active loudspeaker 5. The ADAM loudspeaker: passive option, active optimum 1. Active versus Passive – the Situation In any hifi-system, the loudspeakers are the pivotal component concerning sound quality. That is not to say that the other components do not matter. Nevertheless, it is indisputable that the loudspeaker is decisive for the sound of a hifi-system. It is – besides the acoustical properties of the listening room and the recording itself – the core of any music reproduction. The history of loudspeaker development has produced a great variety of very different systems and designs. The circuit technology of the frequency-separating filter that separates the audio signal into different frequency ranges is determining the design of a loudspeaker. In this respect we distinguish between active and passive systems. Usually, this is a topic that is often underestimated in its importance for sound quality. Active-passive is much more than just a technical negligibility: In fact, the impact of the dividing network on the overall sound of a loudspeaker is substantial. Active or passive – which system is preferable? Considering the aspects mentioned before, it may become a little more comprehensive why the very question comes up over and over again in the hifi-world. For decades it has been spooking as a debate on principles in the journals and magazines and for some time, now, in the web forums. -
Introduction to the Digital Snake
TABLE OF CONTENTS What’s an Audio Snake ........................................4 The Benefits of the Digital Snake .........................5 Digital Snake Components ..................................6 Improved Intelligibility ...........................................8 Immunity from Hums & Buzzes .............................9 Lightweight & Portable .......................................10 Low Installation Cost ...........................................11 Additional Benefits ..............................................12 Digital Snake Comparison Chart .......................14 Conclusion ...........................................................15 All rights reserved. No part of this publication may be reproduced in any form without the written permission of Roland System Solutions. All trade- marks are the property of their respective owners. Roland System Solutions © 2005 Introduction Digital is the technology of our world today. It’s all around us in the form of CDs, DVDs, MP3 players, digital cameras, and computers. Digital offers great benefits to all of us, and makes our lives easier and better. Such benefits would have been impossible using analog technology. Who would go back to the world of cassette tapes, for example, after experiencing the ease of access and clean sound quality of a CD? Until recently, analog sound systems have been the standard for sound reinforcement and PA applications. However, recent technological advances have brought the benefits of digital audio to the live sound arena. Digital audio is superior -
VCSEL Pulse Driver Designs for Tof Applications
Vixar Application Note VCSEL Pulse Driver Designs for ToF Applications 1 Introduction ............................................................................................................................. 2 2 Design Theory ......................................................................................................................... 2 2.1 Schematic Components .................................................................................................... 2 2.2 Design Inductance ............................................................................................................ 3 2.3 Rise and Fall Time ........................................................................................................... 5 2.4 Timing Delay.................................................................................................................... 5 3 Low Power Driver Design ...................................................................................................... 5 4 High Power Driver Design...................................................................................................... 7 4.1 GaN FETs ......................................................................................................................... 7 4.2 Gate Drivers ..................................................................................................................... 7 5 VCSEL Performance .............................................................................................................. 8 6 Conclusions -
Audio Interface User's Manual
Audio Interface User’s Manual Eurorack Synthesizer Modules 14 HP TABLE OF CONTENTS 1.INTRODUCTION 2.WARRANTY 3.INSTALLATION 4.FUNCTION OF PANEL COMPONENTS 5.SIGNALFLOW & ROUTING 6.SPECIFICATIONS 2 1. INTRODUCTION Audiophile Circuits League. -The main purpose of the ACL Audio Interface module is to interface modular synthesizer systems with professional audio recording and stage equipment. The combination of studio quality signal path, �lexible routing possibilities and a headphoneheadphones ampli�ier, with low capabledistortion, of drivingmakes theboth connection high and low between impedance these different environments effortless and sonically transparent. The ACL Audio Interface offers balanced to unbalanced and unbalanced to balanced stereo lines with level controls. The stereo signal from the auxiliary input,either alsowith with balanced level tocontrol, unbalanced, can be oroptionally unbalanced routed to balanced to and mixed line signals,together or can be muted. The headphone ampli�ier can also get its signal from one or the other line after the level control and mixing stage, or can be muted. Since the ampli�ier is AC coupled only at the input, but not at the output, there is an on-board DC protection circuit included. In case the headphone ampli�ier is driven into clipping, the protection can also be tripped. The module has a soft start function* and one overload indicator for every line. *With the soft start function, the interface switch is turned on after a while after turning on the Eurorack main unit. This function can prevent output of unexpecteddamage to the sound speaker. that another module will emit at startup, which will cause 3 2. -
MINIDISC MANUAL V3.0E Table of Contents
MINIDISC MANUAL V3.0E Table of Contents Introduction . 1 1. The MiniDisc System 1.1. The Features . 2 1.2. What it is and How it Works . 3 1.3. Serial Copy Management System . 8 1.4. Additional Features of the Premastered MD . 8 2. The production process of the premastered MD 2.1. MD Production . 9 2.2. MD Components . 10 3. Input components specification 3.1. Sound Carrier Specifications . 12 3.2. Additional TOC Data / Character Information . 17 3.3. Label-, Artwork- and Print Films . 19 3.4. MiniDisc Logo . 23 4. Sony DADC Austria AG 4.1. The Company . 25 5. Appendix Form Sheets Introduction T he quick random access of Compact Disc players has become a necessity for music lovers. The high quality of digital sound is now the norm. The future of personal audio must meet the above criteria and more. That’s why Sony has created the MiniDisc, a revolutionary evolution in the field of digital audio based on an advanced miniature optical disc. The MD offers consumers the quick random access, durability and high sound quality of optical media, as well as superb compactness, shock- resistant portability and recordability. In short, the MD format has been created to meet the needs of personal music entertainment in the future. Based on a dazzling array of new technologies, the MiniDisc offers a new lifestyle in personal audio enjoyment. The Features 1. The MiniDisc System 1.1. The Features With the MiniDisc, Sony has created a revolutionary optical disc. It offers all the features that music fans have been waiting for. -
The Microphone Feedback Analogy for Chatter in Machining
Hindawi Publishing Corporation Shock and Vibration Volume 2015, Article ID 976819, 5 pages http://dx.doi.org/10.1155/2015/976819 Research Article The Microphone Feedback Analogy for Chatter in Machining Tony Schmitz UniversityofNorthCarolinaatCharlotte,Charlotte,NC28223,USA Correspondence should be addressed to Tony Schmitz; [email protected] Received 16 March 2015; Accepted 13 May 2015 Academic Editor: Georges Kouroussis Copyright © 2015 Tony Schmitz. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. This paper provides experimental evidence for the analogy between the time-delay feedback in public address systems and chatter in machining. Machining stability theory derived using the Nyquist criterion is applied to predict the squeal frequency in a microphone/speaker setup. Comparisons between predictions and measurements are presented. 1. Introduction with the workpiece surface causes the tool to begin vibrating and the oscillations in the normal direction to be copied Self-excited vibration, or regenerative chatter, in machining onto the workpiece [4]. When the workpiece begins its has been studied for many years. The research topic has second revolution, the vibrating tool encounters the wavy encouraged the application of mathematics, dynamics (linear surfaceproducedduringthefirstrevolution.Subsequently, and nonlinear), controls, heat transfer, tribology, and other -
Recording and Amplifying of the Accordion in Practice of Other Accordion Players, and Two Recordings: D
CA1004 Degree Project, Master, Classical Music, 30 credits 2019 Degree of Master in Music Department of Classical music Supervisor: Erik Lanninger Examiner: Jan-Olof Gullö Milan Řehák Recording and amplifying of the accordion What is the best way to capture the sound of the acoustic accordion? SOUNDING PART.zip - Sounding part of the thesis: D. Scarlatti - Sonata D minor K 141, V. Trojan - The Collapsed Cathedral SOUND SAMPLES.zip – Sound samples Declaration I declare that this thesis has been solely the result of my own work. Milan Řehák 2 Abstract In this thesis I discuss, analyse and intend to answer the question: What is the best way to capture the sound of the acoustic accordion? It was my desire to explore this theme that led me to this research, and I believe that this question is important to many other accordionists as well. From the very beginning, I wanted the thesis to be not only an academic material but also that it can be used as an instruction manual, which could serve accordionists and others who are interested in this subject, to delve deeper into it, understand it and hopefully get answers to their questions about this subject. The thesis contains five main chapters: Amplifying of the accordion at live events, Processing of the accordion sound, Recording of the accordion in a studio - the specifics of recording of the accordion, Specific recording solutions and Examples of recording and amplifying of the accordion in practice of other accordion players, and two recordings: D. Scarlatti - Sonata D minor K 141, V. Trojan - The Collasped Cathedral. -
Distortion Improvement in the Current Coil of Loudspeakers Gaël Pillonnet, Eric Sturtzer, Timothé Rossignol, Pascal Tournier, Guy Lemarquand
Distortion improvement in the current coil of loudspeakers Gaël Pillonnet, Eric Sturtzer, Timothé Rossignol, Pascal Tournier, Guy Lemarquand To cite this version: Gaël Pillonnet, Eric Sturtzer, Timothé Rossignol, Pascal Tournier, Guy Lemarquand. Distortion improvement in the current coil of loudspeakers. Audio Engineering Society Convention, May 2013, Roma, Italy. hal-01103598 HAL Id: hal-01103598 https://hal.archives-ouvertes.fr/hal-01103598 Submitted on 15 Jan 2015 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. AES Audio Engineering Society Convention Paper Presented at the 134th Convention 2013 May 4–7 Rome, Italy This Convention paper was selected based on a submitted abstract and 750-word precis that have been peer reviewed by at least two qualified anonymous reviewers. The complete manuscript was not peer reviewed. This convention paper has been reproduced from the author's advance manuscript without editing, corrections, or consideration by the Review Board. The AES takes no responsibility for the contents. Additional papers may be obtained by sending request and remittance to Audio Engineering Society, 60 East 42nd Street, New York, New York 10165-2520, USA; also see www.aes.org. All rights reserved.