Avalanche photo diode (APD) receiver modules arewidely used in fi ber optic communication systems. AnAPD module contains the APD and a signal conditioningamplifi er, but is not completely self contained. It stillrequires signifi cant support circuitry including a highvoltage, low noise power supply and a precision currentmonitor to indicate the signal strength. The challenge issqueezing this support circuitry into applications withlimited board space. The LT®3482 addresses this challengeby integrating a monolithic DC/DC step-up converter andan accurate current monitor. The LT3482 can supportup to a 90V APD bias voltage, and the current monitorprovides better than 10% accuracy over four decades ofdynamic range (250nA to 2.5mA).
上传时间: 2014-01-18
上传用户:wenyuoo
The LTC®4151 is a high side power monitor that includesa 12-bit ADC for measuring current and voltage, as wellas the voltage on an auxiliary input. Data is read throughthe widely used I2C interface. An unusual feature in thisdevice is its 7V to 80V operating range, allowing it to coverapplications from 12V automotive to 48V telecom.
上传时间: 2013-10-29
上传用户:集美慧
The LTC®4099 high effi ciency USB power manager andLi-Ion/Polymer battery charger seamlessly managespower distribution from multiple sources in portableapplications. It is differentiated from other USB powermanagers by its bidirectional I2C port that allows the hostmicroprocessor to control and monitor all aspects of theUSB power management and battery charging processes.In addition, a programmable interrupt generation functionalerts the host microprocessor to changes in device statusand provides unprecedented control of power managementfunctions. This high degree of confi gurability allowspost-layout changes in operation, even changes in thefi eld, and it allows a single qualifi ed device to be usedin a variety of products, thus reducing design time andeasing inventory management.
上传时间: 2013-10-22
上传用户:18602424091
–Mastar系列焊接电源–Monitor系列焊接电源–TETRIX系列焊接电源–Phoenix系列焊接电源
上传时间: 2013-11-23
上传用户:Bunyan
SBC2440-III是深圳市天漠科技有限公司推出的采用Samsung公司S3C2440为CPU,采用核心板与母板结构设计的一款嵌入式单板计算机。预装Linux2.6.24或Microsoft Windows CE5.0实时多任务操作系统,并且提供了免费的交叉编译工具链,此工具链由著名的GNU社区维护。用户可以在此基本上按照自己的需求作相应的快速开发,实现产品快速上市。 天漠科技为SBC2440-III的所有接口提供了标准API接口,客户可直接调用来操作板上的接口与资源。同时我们也提供了相关的源代码,增大了用户对产品的可操作性,以及后续的产品维护。
上传时间: 2013-10-09
上传用户:lunshaomo
在航电系统维护过程中,为解决定位故障的效率和降低维修成本等问题,提出了基于ICD(Interface Control Document,接口控制文件)的1553B总线的信息监控系统模型。该系统运用数据采集卡对总线中传输的信号有无失真、偏差等电气特性进行检测,并使用1553B通讯卡通过测控软件LabWindows/CVI编程与ICD数据库的动态链接,实现总线信息的解析和故障的判断。与传统的维护过程相比,这种模型能够从信号的电气特性以及信息的解析等全方位的去检测判断故障的来源,并且能够广泛在其他1553B总线系统内扩展应用。验证表明该监控系统可以对总线信息进行快速有效地监测分析,能满足应用需求。 Abstract: In the process of avionics system maintenance, to solve the problems such as improving the efficiency of fast orientation to troubles and reducing maintenance cost, system of 1553B bus information monitor model based on ICD was proposed. The system observed whether the data which transmitted on the bus appear distortion and deviation by using data acquisition card. And using 1553B communication card programming of the measure software LabWindows/CVI and the dynamic linking of ICD database, message analysis and fault estimation could be realized. Compared with traditional maintenance, this model can all-dimensionally detect and analyze the source of faults from both electrical characteristics of the signal and message analysis, and it can be widely applied in the other 1553B system. Experiment shown that this monitor system can effectively detect and analyze the bus message and can meet the application requirements.
上传时间: 2013-11-23
上传用户:18752787361
以89S52单片机和EP1C6Q240C8型FPGA为控制核心的多功能计数器,是由峰值检波、A/D转换、程控放大、比较整形、移相网络部分组成,可实现测量正弦信号的频率、周期和相位差的功能。多功能计数器采用等精度的测量方法,可实现频率为1Hz~10MHz、幅度为0.01~5Vrms的正弦信号的精确测频,以及频率为10Hz~100kHz、幅度为0.5~5Vrms的正弦信号精确测相。液晶显示器能够实时显示当前信号的频率、周期和相位差。该多功能计数器精度高,界面友好,实用性强。 Abstract: A multi-function counter,which uses89S52MCU and EP1C6Q240C8FPGA as a control core,consists of peak detector,A/D conversion,program-controlled amplification,compared shaping and phase-shifting network part.The counter measures the frequency,period and phase of sinusoidal signal.With the equal precision method,the multi-function counter achieves the precise frequency measurement of the sinusoidal signal which its frequency is from1Hz to10MHz,its amplitude is from0.01Vrms to5Vrms,as well as the accurate phase measurement of the sinusoidal signal which its frequency is from10Hz to100kHz,its amplitude is from0.5Vrms to5Vrms.The LCD monitor real-time displays the frequency,period and phase difference of current signal.The multi-function counter features high precision,friendly interface,and strong practical.
上传时间: 2013-11-15
上传用户:gy592333
气压是气象监测中的一个重要参数,提出了一种气压数据采集模块设计方案,该模块采用数字气压传感器MS5534B、MSP430单片机MSP430F2272和带实时时钟(RTC)64 KB铁电存储器。通过低功耗软件设计方法以微安级整体平均功耗实现了气压数据的采集和存储,适合电池供电的连续高精度气压采集应用。给出了模块的软硬件设计以及MS5534B的性能指标和使用经验。 Abstract: Air pressure is an important parameter in weather monitor.This paper futs forward a new design scheme of low power-air pressure data acquisition module.The module uses a digital output barometer sensor MS5534B,MSP430 microcontroller MSP430F2272 and integrated RTC 64KB FRAM,precision air pressure measurement and storage chip.Another point of this module is low power consumption, so it is well suited for battery powered air pressure data acquisition applications. At the same time,the software and hardware deign of module is presented,And the speciaties and use notices of MS5534B are given.
上传时间: 2014-12-27
上传用户:drink!
为解决输油管道温度压力参数实时监测的问题,设计了以C8051F930单片机作为控制核心的超低功耗输油管道温度压力远程监测系统。现场仪表使用高精度电桥采集数据,通过433 MHz短距离无线通信网络与远程终端RTU进行通信,RTU通过GPRS网络与PC上位机进行远程数据传输,在上位机中实现数据存储和图形化界面显示,从而实现输油管道温度压力参数的实时监测和异常报警。经实验证明,该系统的12位数据采集精度满足设计要求,漏码率小于1%,正常工作时间超过5个月,能实时有效地监测输油管道的温度压力参数,节省大量人工成本,有效预防管道参数异常造成的经济损失和环境污染。 Abstract: In order to solve the problems on real-time monitoring of pipeline temperature and pressure parameters, the ultra-low power remote pipeline temperature and pressure monitoring system was designed by using the single chip processor C8051F930 as the control core. The high-precision electric bridge was used in field instruments for data collection, the 433MHz short-range wireless communication network was used to make communication between field instrument and RTU, the GPRS was used by the RTU to transmit data to the PC host computer, and the data was stored and displayed in the PC host computer, so the real-time monitoring and exception alerts of pipeline temperature and pressure parameters were achieved. The experiment proves that the system of which error rate is less than 1% over five months working with the 12-bit data acquisition accuracy can effectively monitor the pipeline temperature and pressure parameters in real time, it saves a lot of labor costs and effectively prevents environmental pollution and economic losses caused by abnormal channel parameters.
上传时间: 2013-11-07
上传用户:cuibaigao
第一章 序論……………………………………………………………6 1- 1 研究動機…………………………………………………………..7 1- 2 專題目標…………………………………………………………..8 1- 3 工作流程…………………………………………………………..9 1- 4 開發環境與設備…………………………………………………10 第二章 德州儀器OMAP 開發套件…………………………………10 2- 1 OMAP介紹………………………………………………………10 2-1.1 OMAP是什麼?…….………………………………….…10 2-1.2 DSP的優點……………………………………………....11 2- 2 OMAP Architecture介紹………………………………………...12 2-2-1 OMAP1510 硬體架構………………………………….…12 2-2.2 OMAP1510軟體架構……………………………………...12 2-2.3 DSP / BIOS Bridge簡述…………………………………...13 2- 3 TI Innovator套件 -- OMAP1510 ……………………………..14 2-2.1 General Purpose processor -- ARM925T………………...14 2-2.2 DSP processor -- TMS320C55x …………………………15 2-2.3 IDE Tool – CCS …………………………………………15 2-2.4 Peripheral ………………………………………………..16 第三章 在OMAP1510上建構Embedded Linux System…………….17 3- 1 嵌入式工具………………………………………………………17 3-1.1 嵌入式程式開發與一般程式開發之不同………….….17 3-1.2 Cross Compiling的GNU工具程式……………………18 3-1.3 建立ARM-Linux Cross-Compiling 工具程式………...19 3-1.4 Serial Communication Program………………………...20 3- 2 Porting kernel………………………………………………….…21 3-2.1 Setup CCS ………………………………………….…..21 3-2.2 編譯及上傳Loader…………………………………..…23 3-2.3 編譯及上傳Kernel…………………………………..…24 3- 3 建構Root File System………………………………………..…..26 3-3.1 Flash ROM……………………………………………...26 3-3.2 NFS mounting…………………………………………..27 3-3.3 支援NFS Mounting 的kernel…………………………..27 3-3.4 提供NFS Mounting Service……………………………29 3-3.5 DHCP Server……………………………………………31 3-3.6 Linux root 檔案系統……………………………….…..32 3- 4 啟動及測試Innovator音效裝置…………………………..…….33 3- 5 建構支援DSP processor的環境…………………………...……34 3-5.1 Solution -- DSP Gateway簡介……………………..…34 3-5.2 DSP Gateway運作架構…………………………..…..35 3- 6 架設DSP Gateway………………………………………….…36 3-6.1 重編kernel……………………………………………...36 3-6.2 DEVFS driver…………………………………….……..36 3-6.3 編譯DSP tool和API……………………………..…….37 3-6.4 測試……………………………………………….…….37 第四章 MP3 Player……………………………………………….…..38 4- 1 MP3 介紹………………………………………………….…….38 4- 2 MP3 壓縮原理……………………………………………….….39 4- 3 Linux MP3 player – splay………………………………….…….41 4.3-1 splay介紹…………………………………………….…..41 4.3-2 splay 編譯………………………………………….…….41 4.3-3 splay 的使用說明………………………………….……41 第五章 程式改寫………………………………………………...…...42 5-1 程式評估與改寫………………………………………………...…42 5-1.1 Inter-Processor Communication Scheme…………….....42 5-1.2 ARM part programming……………………………..…42 5-1.3 DSP part programming………………………………....42 5-2 程式碼………………………………………………………..……43 5-3 雙處理器程式開發注意事項…………………………………...…47 第六章 效能評估與討論……………………………………………48 6-1 速度……………………………………………………………...48 6-2 CPU負載………………………………………………………..49 6-3 討論……………………………………………………………...49 6-3.1分工處理的經濟效益………………………………...49 6-3.2音質v.s 浮點與定點運算………………………..…..49 6-3.3 DSP Gateway架構的限制………………………….…50 6-3.4減少IO溝通……………….………………………….50 6-3.5網路掛載File System的Delay…………………..……51 第七章 結論心得…
上传时间: 2013-10-14
上传用户:a471778