Many complex systems—such as telecom equipment,memory modules, optical systems, networking equipment,servers and base stations—use FPGAs and otherdigital ICs that require multiple voltage rails that muststart up and shut down in a specific order, otherwise theICs can be damaged. The LTC®2924 is a simple andcompact solution to power supply sequencing in a 16-pinSSOP package (see Figures 1 and 2).
上传时间: 2013-10-29
上传用户:tonyshao
A number of conventional solutions have been available forthe design of a DC/DC converter where the output voltageis within the input voltage range—a common scenarioin Li-Ion battery-powered applications—but none werevery attractive until now. Conventional topologies, suchas SEPIC or boost followed by buck, have numerousdisadvantages, including low effi ciency, complex magnetics,polarity inversion and/or circuit complexity/cost. TheLTC®3785 buck-boost controller yields a simple, effi cient,low parts-count, single-converter solution that is easyto implement, thus avoiding the drawbacks associatedwith traditional solutions.
上传时间: 2013-10-21
上传用户:ljt101007
Once relegated to the hinterlands of low cost indicatorlights, the LED is again in the spotlight of the lightingworld. LED lighting is now ubiquitous, from car headlightsto USB-powered lava lamps. Car headlights exemplifyapplications that capitalize on the LED’s clear advantages—unwavering high quality light output, tough-assteelrobustness, inherent high effi ciency—while a USBlava lamp exemplifi es applications where only LEDs work.Despite these clear advantages, their requirement forregulated voltage and current make LED driver circuitsmore complex than the venerable light bulb, but some newdevices are closing the gap. For instance, the LTM®8040μModule™ LED driver integrates all the driver circuitryinto a single package, allowing designers to refocus theirtime and effort on the details of lighting design criticalto a product’s success.
上传时间: 2013-10-16
上传用户:togetsomething
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
As logic systems get larger and more complex, theirsupply current requirements continue to rise. Systemsrequiring 100A are fairly common. A high current powersupply to meet such requirements usually requires parallelingseveral power regulators to alleviate the thermalstress on the individual power components. A powersupply designer is left with the choice of how to drive theseparalleled regulators: brute-force single-phase or smartPolyPhaseTM.
上传时间: 2013-10-08
上传用户:zhqzal1014
为了提高传统温度控制系统的性能,将PID控制理论与嵌入式系统相结合,采用瑞萨电子公司的H8S/2166作为核心处理器,AD公司的AD7705以及热敏电阻温度传感器作为温度检测单元,利用4×6小键盘、LCD显示器和S1D13305液晶控制器达到良好的人机交互,设计出了一个应用于化工领域的嵌入式实时温度控制系统。相比于传统温度控制系统,该系统提供了更强的计算能力和可扩展能力,采用增量PID控制算法实现复杂控制。通过实验,该系统能达到0.1 ℃的温度控制精度以及小于120 s的温度稳定时间。 Abstract: In order to improve the performance of conventional temperature control system, combining PID control theory with embedded systems, using the Renesas Electronics Corp. H8S/2166 micro-controller as a core processors, AD7705 and thermistor temperature sensor as a temperature detection unit and 4×6 small keyboard, LCD and S1D13305 LCD controller as a good human-computer interaction, this paper designed an embedded real-time temperature control system which is applied in chemical industry. Compared with conventional temperature control system, this system provides more computing power and extensibility, and adopts PID control algorithm for complex control. Through the experiment, the system can reach temperature control accuracy of 0.1 ℃ and temperature stabilization time of less than 120 seconds.
上传时间: 2014-12-26
上传用户:003030
AVR32801: UC3A3 Schematic Checklist Features • Power circuit • Reset circuit • USB connection • External bus interface • ABDAC sound DAC interface • JTAG and Nexus debug ports • Clocks and crystal oscillators • MMC, SD-card, SDHC, SDIO and CE-ATA interface 1 Introduction A good hardware design comes from a proper schematic. Since UC3A3 devices have a fair number of pins and functions, the schematic for these devices can be large and quite complex. This application note describes a common checklist which should be used when starting and reviewing the schematics for a UC3A3 design.
标签: Schematic 32801 UC3A3 Chec
上传时间: 2014-12-26
上传用户:DXM35
虽然PIC都是8位的单片机,但都采用RISC(Reduced Instruction Set Computing)核心结构,这有别于过去一般的CISC(Complex Instruction Set Computing)结构。所谓RISC结构就是采用哈佛双总线结构,将地址总线与数据总线分开,因此在同一个指令执行过程中,数据与地址可以同时传送,避免了总线处理上的瓶颈。
上传时间: 2013-11-21
上传用户:tianyi223
机电类比法是一种把机械量通过一定的计算等效类比为电量的方法,其在对电子机械系统的分析中应用非常广泛。它能够把一个较复杂的机械系统类比为我们熟知的电路系统来进行分析,从而使问题的分析得到简化。本文通过对振弦式传感器的分析介绍了机电类比法,并对使用电路进行了相关的分析。 Summary:The electromechanical analogy is assort of analysis which is to analogize the mechanical system by using circuit system , it applied widely in the filed of analysis the electronic-mechanical system. The analysis can take a complex mechanical system analogous to a circuitry that we well-known, which can simplify the problems. In the paper, the electro-mechanical analogy method is briefly introduced by analysis the vibrating wire sensor,and have a correlation analysis about the circuit we used.关键词: 机电类比法 振弦式传感器 频率 振荡 反馈Keyword:electro-mechanical analogy method,vibrating wire sensor,frequency, oscillation, feedback 0 引言振弦式传感器是属于频率式传感器的一种。所谓频率式传感器就是能直接将被测量转换为振动频率信号的传感器,这类传感器一般是通过测量振弦、振筒、振梁、振膜等弹性振体或石英晶体谐振器的固有谐振频率来达到测量引起谐振频率变化的被测非电量的目的,其也称为谐振式传感器[1]。在分析该类传感器中,由于其涉及到频率,就容易让人联想到在电子技术中接触到的RLC振荡电路。因此可以尝试着用类比的方法使之对应起来分析,即机电类比法分析。
上传时间: 2013-11-16
上传用户:paladin
CodeWarrior Development Tool Suites are comprehensive integrated developmentenvironments (IDE) that provide a highly visual and automated framework toaccelerate the development of the most complex embedded applications. Acrossmost stages of the development cycle, we offer tools to help configure, debug andoptimize your design built on Freescale MPUs, MCUs, DSPs and DSCs. These toolsuites provide solutions to get your design up and running fast.
标签: CodeWarrior 开发工具套件
上传时间: 2013-11-07
上传用户:youlongjian0