Industrial systems demand semiconductors that are precise, flexibleand reliable. Linear Technology offers a broad line of high performanceanalog ICs that simplify system design with rugged devices featuringparameters fully guaranteed over the -40°C to 85°C temperature range.We back this up with knowledgeable applications support, long productlife cycles and superior on-time delivery.
上传时间: 2013-11-02
上传用户:xiaodu1124
Digital convergence, in recent history, has been prevalentin the consumer equipment domain and the designengineers in this area have been struggling with a plethoraof emerging standards and protocols. What lessons can welearn from their struggle? The same dilemmas now existin in-vehicle telematics and infotainment systems but withthe added issues of extremes of temperature, safety,security, and time in market.
上传时间: 2014-12-23
上传用户:9牛10
Control systems are becoming increasingly dependent on digital processing and so require sensors able to provide direct digital inputs. Sensors based on time measurement, having outputs based on a frequency or phase, have an advantage over conventional analogue sensors in that their outputs can be measured directly in digital systems by pulse counting.
上传时间: 2013-10-08
上传用户:wuyuying
ANALOG INPUT BANDWIDTH is a measure of the frequencyat which the reconstructed output fundamental drops3 dB below its low frequency value for a full scale input. Thetest is performed with fIN equal to 100 kHz plus integer multiplesof fCLK. The input frequency at which the output is −3dB relative to the low frequency input signal is the full powerbandwidth.APERTURE JITTER is the variation in aperture delay fromsample to sample. Aperture jitter shows up as input noise.APERTURE DELAY See Sampling Delay.BOTTOM OFFSET is the difference between the input voltagethat just causes the output code to transition to the firstcode and the negative reference voltage. Bottom Offset isdefined as EOB = VZT–VRB, where VZT is the first code transitioninput voltage and VRB is the lower reference voltage.Note that this is different from the normal Zero Scale Error.CONVERSION LATENCY See PIPELINE DELAY.CONVERSION TIME is the time required for a completemeasurement by an analog-to-digital converter. Since theConversion Time does not include acquisition time, multiplexerset up time, or other elements of a complete conversioncycle, the conversion time may be less than theThroughput Time.DC COMMON-MODE ERROR is a specification which appliesto ADCs with differential inputs. It is the change in theoutput code that occurs when the analog voltages on the twoinputs are changed by an equal amount. It is usually expressed in LSBs.
上传时间: 2013-11-12
上传用户:pans0ul
使用时钟PLL的源同步系统时序分析一)回顾源同步时序计算Setup Margin = Min Clock Etch Delay – Max Data Etch Delay – Max Delay Skew – Setup TimeHold Margin = Min Data Etch Delay – Max Clock Etch Delay + Min Delay Skew + Data Rate – Hold Time下面解释以上公式中各参数的意义:Etch Delay:与常说的飞行时间(Flight Time)意义相同,其值并不是从仿真直接得到,而是通过仿真结果的后处理得来。请看下面图示:图一为实际电路,激励源从输出端,经过互连到达接收端,传输延时如图示Rmin,Rmax,Fmin,Fmax。图二为对应输出端的测试负载电路,测试负载延时如图示Rising,Falling。通过这两组值就可以计算得到Etch Delay 的最大和最小值。
上传时间: 2013-11-05
上传用户:VRMMO
Industrial remote monitoring systems and keep-alivecircuits spend most of their time in standby mode. Manyof these systems also depend on battery power, so powersupply effi ciency in standby state is very important tomaximize battery life. The LT®8410/-1 high effi ciencyboost converter is ideal for these systems, requiringonly 8.5μA of quiescent current in standby mode. Thedevice integrates high value (12.4M/0.4M) output feedbackresistors, signifi cantly reducing input current whenthe output is in regulation with no load. Other featuresinclude an integrated 40V switch and Schottky diode,output disconnect with current limit, built in soft-start,overvoltage protection and a wide input range, all in atiny 8-pin 2mm × 2mm DFN package.
上传时间: 2013-11-23
上传用户:新手无忧
为了改变目前电网现场作业管理的变电巡检、变电检修试验、输电线路巡检检修等管理系统各自独立运行,信息不能共享,功能、效率受限,建设和维护成本高的现状,提出了采用B/S+C/S构架模式,将各现场作业管理模块和生产MIS(管理系统)集成为一体的现场作业管理系统的设计方案,做到各子系统和生产MIS软硬资源共享,做到同一数据唯一入口、一处录入多处使用。各子系统设备人员等基础信息来源于生产管理系统,各子系统又是生产管理系统的作业数据、缺陷信息的重要来源。经过研究试用成功和推广应用,目前该系统已在江西电网220 kV及以上变电站全面应用。 Abstract: In order to improve the status that the substation field inspection system, substation equipments maintenance and testing system, power-line inspection and maintenance system are running independent with each other. They can?蒺t share the resource information which accordingly constrains their functions and efficiency, and their construction and maintenance costs are high. This paper introduces a field standardized work management system based on B/S+C/S mode, integrating all field work management systems based on MIS and share the equipments and employee?蒺s data of MIS,the field work data of the sub systems are the source information of MIS, by which the same single data resouce with one-time input can be utilized in multiple places. After the research and testing, this system is triumphantly using in all 220kV and above substations in Jiangxi grid.
上传时间: 2013-11-15
上传用户:han_zh
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
目录: 1. Character Type Functions - 字符类型函数 2. Standard C Input/Output Functions - 标准输入输出函数 3. Standard Library Functions - 标准库和内存分配函数 4. Mathematical Functions - 数学函数 5. String Functions - 字符串函数 6. BCD Conversion Functions - BCD 转换函数 7. Memory Access Functions - 存储器访问函数 8. Delay Functions - 延时函数 9. LCD Functions - LCD函数 10. LCD Functions for displays with 4x40 characters - 4×40 字符型LCD函数 11. LCD Functions for displays connected in 8 bit memory mapped mode -以8 位外部存储 器模式接口的LCD显示函数 12. I2C Bus Functions - I2C 总线函数 13. National Semiconductor LM75 Temperature Sensor Functions - LM75 温度传感器函数 14. Dallas Semiconductor DS1621 Thermometer/Thermostat Functions - DS1621 温度计函 数 15. Philips PCF8563 Real Time Clock Functions - PCF8563 实时时钟函数 16. Philips PCF8583 Real Time Clock Functions - PCF8583 实时时钟函数 17. Dallas Semiconductor DS1302 Real Time Clock Functions - DS1302 实时时钟函数 18. Dallas Semiconductor DS1307 Real Time Clock Functions - DS1307 实时时钟函数 19. 1 Wire Protocol Functions - 单线通讯协议函数 20. Dallas Semiconductor DS1820/DS1822 Temperature Sensors Functions - DS1820/1822 温度传感器函数 21. SPI Functions - SPI 函数 22. Power Management Functions - 电源管理函数 23. Gray Code Conversion Functions - 格雷码转换函数
上传时间: 2013-10-22
上传用户:归海惜雪
飞机电网故障时,机载电气盒必须在延迟时间内切断电网,保护机载设备。采用AT89S52设计的电气盒测试仪能够测试电气盒保护功能,测量延迟时间。实际应用结果表明,该测试仪具有测量准确、可靠性高、成本低等优点。 Abstract: The helicopter-electrical-box must shut off the helicopter power,protect the equipments of the helicopter when the helicopter power is failed.The tester for the helicopter-electrical-box based on AT89S52is used for testing the protect-ing function and measuring the delay time.Application results show this tester has some advantages,such as accurate mea-surement,high dependability,economical cost etc.
上传时间: 2014-12-27
上传用户:786334970