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).
上傳時(shí)間: 2013-10-29
上傳用戶:tonyshao
Video cable driver amplifi er output stages traditionallyrequire a supply voltage of at least 6V in order to providethe required output swing. This requirement is usuallymet with 5V supplies by adding a boost regulator or asmall local negative rail, say via the popular LT®1983-3.Such additional circuitry is unnecessary in typical 1VP-Pvideo connections, such as HD component video, if thecable driver amplifi ers simply offer near rail-to-rail outputcapability when powered from 5V.
上傳時(shí)間: 2013-11-16
上傳用戶:yanyangtian
As environmental concerns over traditional lighting increaseand the price of LEDs decreases, high power LEDsare fast becoming a popular lighting solution for offl ineapplications. In order to meet the requirements of offl inelighting—such as high power factor, high effi ciency, isolationand TRIAC dimmer compatibility—prior LED driversused many external discrete components, resulting incumbersome solutions. The LT®3799 solves complexity,space and performance problems by integrating all therequired functions for offl ine LED lighting.
上傳時(shí)間: 2013-10-13
上傳用戶:dongqiangqiang
為了改變目前電網(wǎng)現(xiàn)場(chǎng)作業(yè)管理的變電巡檢、變電檢修試驗(yàn)、輸電線路巡檢檢修等管理系統(tǒng)各自獨(dú)立運(yùn)行,信息不能共享,功能、效率受限,建設(shè)和維護(hù)成本高的現(xiàn)狀,提出了采用B/S+C/S構(gòu)架模式,將各現(xiàn)場(chǎng)作業(yè)管理模塊和生產(chǎn)MIS(管理系統(tǒng))集成為一體的現(xiàn)場(chǎng)作業(yè)管理系統(tǒng)的設(shè)計(jì)方案,做到各子系統(tǒng)和生產(chǎn)MIS軟硬資源共享,做到同一數(shù)據(jù)唯一入口、一處錄入多處使用。各子系統(tǒng)設(shè)備人員等基礎(chǔ)信息來(lái)源于生產(chǎn)管理系統(tǒng),各子系統(tǒng)又是生產(chǎn)管理系統(tǒng)的作業(yè)數(shù)據(jù)、缺陷信息的重要來(lái)源。經(jīng)過(guò)研究試用成功和推廣應(yīng)用,目前該系統(tǒng)已在江西電網(wǎng)220 kV及以上變電站全面應(yīng)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.
標(biāo)簽: 電網(wǎng) 信息化 管理系統(tǒng)
上傳時(shí)間: 2013-11-15
上傳用戶:han_zh
The P89LPC912/913/914 are single-chip microcontrollers in low-cost 14-pin packages, based on a high performance processor architecture that executes instructions in two to four clocks, six times the rate of standard 80C51 devices. Many system level functions have been incorporated into the P89LPC912/913/914 in order to reduce component count, board space, and system cost.
上傳時(shí)間: 2013-10-12
上傳用戶:司令部正軍級(jí)
為了提高PCB板制作的效率,改變傳統(tǒng)的化學(xué)腐蝕制板工藝,使用機(jī)械仿形銑制作電路板的方法,設(shè)計(jì)了以ATMEGA16單片機(jī)為核心部件的PCB板雕刻機(jī)控制系統(tǒng)。其中包括PCB雕刻機(jī)的基本功能、主要硬件電路設(shè)計(jì)和軟件的實(shí)現(xiàn)流程,并給出了相關(guān)設(shè)計(jì)電路。重點(diǎn)分析了雕刻機(jī)步進(jìn)電機(jī)的驅(qū)動(dòng)電路以及主軸電機(jī)的驅(qū)動(dòng)電路,該雕刻機(jī)經(jīng)實(shí)際運(yùn)行,系統(tǒng)工作良好,可有效提高PCB板的制作效率。 Abstract: In order to improve the efficiency of production of PCB board and change the traditional chemical etching plates, using of mechanical copying milling method makes circuit boards,this paper introduces the PCB engraving machine control system used ATMEGA16 microcomputer as the core components. It includes basic function, the hardware circuit design and software realization process, and gives the corresponding circuit design.It analyses the drive circuit of engrawing machine stepper motor and spindle motor in detail. This engraving machine by practical operation, the system works well, which can effectively improve the production efficiency of PCB board.
上傳時(shí)間: 2013-10-17
上傳用戶:liangliang123
為解決我國(guó)水位監(jiān)測(cè)野外條件下長(zhǎng)期無(wú)人看守的問(wèn)題,研制開(kāi)發(fā)了基于MSP430單片機(jī)的智能水位計(jì)。從其組成到各功能分別進(jìn)行了詳細(xì)的介紹,該智能水位計(jì)不僅實(shí)現(xiàn)了水位數(shù)據(jù)的實(shí)時(shí)監(jiān)測(cè)、記錄和定期采集等多種工作模式,而且提高了水位監(jiān)測(cè)精度,實(shí)現(xiàn)了水位監(jiān)測(cè)的智能化。 Abstract: In order to solve the problems of long-term unmanned observation in the field water monitoring,an intelligence water-level meter based on MSP430 is developed composition and every function moduce of the water level meter was introduced in detail. It not only realizes water level data collection and storage, regularly gathering and so on, but also improves the water-level precision , finally realizes the intelligence.
標(biāo)簽: MSP 430 單片機(jī) 水位計(jì)
上傳時(shí)間: 2013-11-17
上傳用戶:417313137
為了提高傳統(tǒng)溫度控制系統(tǒng)的性能,將PID控制理論與嵌入式系統(tǒng)相結(jié)合,采用瑞薩電子公司的H8S/2166作為核心處理器,AD公司的AD7705以及熱敏電阻溫度傳感器作為溫度檢測(cè)單元,利用4×6小鍵盤(pán)、LCD顯示器和S1D13305液晶控制器達(dá)到良好的人機(jī)交互,設(shè)計(jì)出了一個(gè)應(yīng)用于化工領(lǐng)域的嵌入式實(shí)時(shí)溫度控制系統(tǒng)。相比于傳統(tǒng)溫度控制系統(tǒng),該系統(tǒng)提供了更強(qiáng)的計(jì)算能力和可擴(kuò)展能力,采用增量PID控制算法實(shí)現(xiàn)復(fù)雜控制。通過(guò)實(shí)驗(yàn),該系統(tǒng)能達(dá)到0.1 ℃的溫度控制精度以及小于120 s的溫度穩(wěn)定時(shí)間。 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.
標(biāo)簽: 瑞薩電子 微控制器 溫度控制 系統(tǒng)設(shè)計(jì)
上傳時(shí)間: 2014-12-26
上傳用戶:003030
為了使音頻信號(hào)分析儀小巧可靠,成本低廉,設(shè)計(jì)了以2片MSP430F1611單片機(jī)為核心的系統(tǒng)。該系統(tǒng)將音頻信號(hào)送入八階巴特沃茲低通濾波器,對(duì)信號(hào)進(jìn)行限幅放大、衰減、電平位移、緩沖,并利用一單片機(jī)負(fù)責(zé)對(duì)前級(jí)處理后的模擬信號(hào)進(jìn)行采樣,將采集得到的音頻信號(hào)進(jìn)行4 096點(diǎn)基2的FFT計(jì)算,并對(duì)信號(hào)加窗函數(shù)提高分辨率,另一單片機(jī)負(fù)責(zé)對(duì)信號(hào)的分析及控制顯示設(shè)備。此設(shè)計(jì)精確的測(cè)量了音頻信號(hào)的功率譜、周期性、失真度指標(biāo),達(dá)到較高的頻率分辨率,并能將測(cè)量結(jié)果通過(guò)紅外遙控器顯示在液晶屏上。 Abstract: o make the audio signal analyzer cheaper, smaller and more reliable, this system sends the audio signal to the eight-order butterworth filter, and then amplifies, attenuates, buffers it in a limiting range, transfers the voltage level of the signal before utilizing two MSP430F1611 MCU to realize the audio analysis. One is charged for sampling and dealing with the processed audio signal collected by the 4096 point radix-2 FFT calculation and imposes the window function to improve the frequency resolution. The other one controls the display and realizes the spectrum, periodicity, power distortion analysis in high resolution which is displayed in the LCD screen through the infrared remote control.
上傳時(shí)間: 2013-12-11
上傳用戶:jasonheung
為了有效地提升鉛酸蓄電池的使用壽命,同時(shí)實(shí)現(xiàn)對(duì)充電過(guò)程的監(jiān)控,設(shè)計(jì)出一種用單片機(jī)控制的36 V鉛酸蓄電池充電電源。本電路采用反激式拓?fù)洌B續(xù)電流工作模式,電源管理IC設(shè)計(jì)在電源的副邊,由ELAN公司的EM78P258N單片機(jī)模擬,是用可編程器件模擬電源管理IC,實(shí)現(xiàn)智能電源低成本化的一次成功嘗試,通過(guò)對(duì)單片機(jī)的軟件設(shè)計(jì)實(shí)現(xiàn)了充電電源的狀態(tài)顯示、充電時(shí)間控制、報(bào)警、過(guò)溫保護(hù)、過(guò)壓保護(hù)、過(guò)流保護(hù)等功能。本充電器真正的實(shí)現(xiàn)了鉛酸蓄電池的三段式充電過(guò)程,其最高輸出功率可達(dá)90 W,效率約85%,成本不到20元,具有很高的市場(chǎng)競(jìng)爭(zhēng)力。 Abstract: In order to extend the life of lead-acid battery efficiently and supervise the charging process meanwhile, a 36V lead-acid battery charge powe supply controlled by microcontroller is designed. The charger is flyback switching power supply and works in CCM mode. A EM78P258N microcontroller made by ELAN microelectronics corporation is used as power management IC which is designed at the secondary circuit. The project is a successful attempt to low-cost intelligent power used microcontroller simulating power management IC. The charger also has the functions of the status reveal, charge time control, alarming, thermal protect, current limit and overvoltage protect by the software design. The circuit actually implements the three-step charge process, whose power is up to 90W and whose efficiency can get 85%. The net cost of this charger is less than 20 RMB, so that the charger is of powerful market competitiveness.
標(biāo)簽: 單片機(jī)控制 充電電源 鉛酸蓄電池
上傳時(shí)間: 2013-11-16
上傳用戶:cepsypeng
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