In a recent discussion with a system designer, the requirementfor his power supply was to regulate 1.5Vand deliver up to 40A of current to a load that consistedof four FPGAs. This is up to 60W of power that must bedelivered in a small area with the lowest height profi lepossible to allow a steady fl ow of air for cooling. Thepower supply had to be surface mountable and operateat high enough effi ciency to minimize heat dissipation.He also demanded the simplest possible solution so histime could be dedicated to the more complex tasks. Asidefrom precise electrical performance, this solution had toremovethe heat generated during DC to DC conversionquickly so that the circuit and the ICs in the vicinity do notoverheat. Such a solution requires an innovative designto meet these criteria:
上传时间： 2013-11-24
上传用户：defghi010
A recent trend in the design of portable devices has beento use ceramic capacitors to filter DC/DC converter inputs.Ceramic capacitors are often chosen because of theirsmall size, low equivalent series resistance (ESR) and highRMS current capability. Also, recently, designers havebeen looking to ceramic capacitors due to shortages oftantalum capacitors.
上传时间： 2013-11-05
上传用户：comer1123
Designing Boards with Atmel AT89C51,AT89C52, AT89C1051, and AT89C2051 for Writing Flash at In-Circuit Test. recent improvements in chips and testers have made it possible for the tester to begin taking over the role tradi-tionally assigned to the PROM program-mer. Instead of having a PROM pro- grammer write nonvolatile memories before assembling the board, the in-cir- cuit tester writes them during in-circuit testing operations. Many Teradyne Z18- series testers are now in use loading code into nonvolatile memories, micro- controllers and in-circuit programmable logic devices. The purpose of this note is to explain how the Z18 approaches the writing task for Atmel AT89C series IC’s, so that designers of boards using these chips can get the best results.
上传时间： 2013-11-17
上传用户：xiaozhiqban
Designing Boards with Atmel AT89C51, AT89C52, AT89C1051, and AT89C2051 for Writing Flash at In-Circuit Test:recent improvements in chips andtesters have made it possible for thetester to begin taking over the role traditionallyassigned to the PROM programmer.Instead of having a PROM programmerwrite nonvolatile memoriesbefore assembling the board, the in-circuittester writes them during in-circuittesting operations. Many Teradyne Z18-series testers are now in use loadingcode into nonvolatile memories, microcontrollersand in-circuit programmable logic devices. The purpose of this note is to explain how the Z18 approaches the writing task for Atmel AT89C series IC’s,so that designers of boards using these chips can get the best results.
标签： Designing Boards Atmel with
上传时间： 2013-11-20
上传用户：lijianyu172
The field of microelectromechanical systems (MEMS), particularly micromachinedmechanical transducers, has been expanding over recent years, and the productioncosts of these devices continue to fall. Using materials, fabrication processes, anddesign tools originally developed for the microelectronic circuits industry, newtypes of microengineered device are evolving all the time—many offering numerousadvantages over their traditional counterparts. The electrical properties of siliconhave been well understood for many years, but it is the mechanical properties thathave been exploited in many examples of MEMS. This book may seem slightlyunusual in that it has four editors. However, since we all work together in this fieldwithin the School of Electronics and Computer Science at the University of Southampton,it seemed natural to work together on a project like this. MEMS are nowappearing as part of the syllabus for both undergraduate and postgraduate coursesat many universities, and we hope that this book will complement the teaching thatis taking place in this area.
上传时间： 2013-10-16
上传用户：朗朗乾坤
Abstract: This article explains the recent trend in heart-rate and fitness monitors to go wireless toeliminate cables to allow free movement, and allow convenient data collection without the need to plug intheir devices. It details a typical wireless system, using the MAX1472 crystal-referenced phase-lockedloop (PLL) VHF/UHF transmitter.
标签： Heart-RateFitness Monitors Wireless Go
上传时间： 2013-11-11
上传用户：xiaowei314
This version of dialog, formerly known as cdialog is based on the Debian package for dialog 0.9a (see CHANGES for recent modifications) 这是一个 unix 系统下的对话框管理程序， 你可以将该程序编译后，直接使用。
标签： dialog formerly version cdialog
上传时间： 2013-12-09
上传用户：playboys0
This book is about the management of business processes. This is certainly not a new topic. Since the beginning of the Industrial Revolution, it has been written about from every possible point of view—economic, sociological, psychological, accountancy, mechanical engineering and business administration. In this book, we examine the management of business processes from the perspective of computing, or—to put it more broadly—of information technology. The reason is that information technology has made huge leaps forward in recent years, resulting in the creation of completely new ways of organizing business processes. The development of generic software packages for managing business processes—so-called workflow management systems (WFMS)—is particularly important in this respect.
标签： This management certainly processes
上传时间： 2013-11-29
上传用户：shus521
OpenSS7 This the fourth public release of the OpenSS7 Master Package. See README in the release for a sub-package listing. Most of the sub-packages in the release are production grade for Linux Fast-STREAMS. All existing validation test suites run clean on supported distributions and architectures. It is unlikely that the OpenSS7 Master Package will be released as frequently as before. Sub-packages will be released more often. To rebuild the master package with a new sub-package release, simply replace the directory to which the sub-package belongs with the unpacked sub-package release and then rebuild the master package. This release provides support for recent distributions and tool chains.
标签： OpenSS7 release the Package
上传时间： 2015-10-27
上传用户：cc1
Web technology is not evolving in comfortable and incremental steps, but i s turbulent, erratic, and often rather uncomfortable. It is estimated that the Internet, arguably the most important part of the new technological environment, has expanded by about 2000 ％ and that is doubling in size every six to ten months. In recent years, the advance in computer and web technologies and the decrease in their cost have expanded the means available to collect and store data. As an intermediate consequence, the amount of information (Meaningful data) stored has been increasing at a very fast pace.
标签： comfortable incremental technology and
上传时间： 2015-11-04
上传用户：Shaikh
