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.
上傳時間: 2013-10-13
上傳用戶:dongqiangqiang
為了改變目前電網現場作業管理的變電巡檢、變電檢修試驗、輸電線路巡檢檢修等管理系統各自獨立運行,信息不能共享,功能、效率受限,建設和維護成本高的現狀,提出了采用B/S+C/S構架模式,將各現場作業管理模塊和生產MIS(管理系統)集成為一體的現場作業管理系統的設計方案,做到各子系統和生產MIS軟硬資源共享,做到同一數據唯一入口、一處錄入多處使用。各子系統設備人員等基礎信息來源于生產管理系統,各子系統又是生產管理系統的作業數據、缺陷信息的重要來源。經過研究試用成功和推廣應用,目前該系統已在江西電網220 kV及以上變電站全面應用。 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.
上傳時間: 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.
上傳時間: 2013-10-12
上傳用戶:司令部正軍級
為了提高PCB板制作的效率,改變傳統的化學腐蝕制板工藝,使用機械仿形銑制作電路板的方法,設計了以ATMEGA16單片機為核心部件的PCB板雕刻機控制系統。其中包括PCB雕刻機的基本功能、主要硬件電路設計和軟件的實現流程,并給出了相關設計電路。重點分析了雕刻機步進電機的驅動電路以及主軸電機的驅動電路,該雕刻機經實際運行,系統工作良好,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.
上傳時間: 2013-10-17
上傳用戶:liangliang123
為解決我國水位監測野外條件下長期無人看守的問題,研制開發了基于MSP430單片機的智能水位計。從其組成到各功能分別進行了詳細的介紹,該智能水位計不僅實現了水位數據的實時監測、記錄和定期采集等多種工作模式,而且提高了水位監測精度,實現了水位監測的智能化。 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.
上傳時間: 2013-11-17
上傳用戶:417313137
為了提高傳統溫度控制系統的性能,將PID控制理論與嵌入式系統相結合,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單元,利用4×6小鍵盤、LCD顯示器和S1D13305液晶控制器達到良好的人機交互,設計出了一個應用于化工領域的嵌入式實時溫度控制系統。相比于傳統溫度控制系統,該系統提供了更強的計算能力和可擴展能力,采用增量PID控制算法實現復雜控制。通過實驗,該系統能達到0.1 ℃的溫度控制精度以及小于120 s的溫度穩定時間。 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.
上傳時間: 2014-12-26
上傳用戶:003030
為了使音頻信號分析儀小巧可靠,成本低廉,設計了以2片MSP430F1611單片機為核心的系統。該系統將音頻信號送入八階巴特沃茲低通濾波器,對信號進行限幅放大、衰減、電平位移、緩沖,并利用一單片機負責對前級處理后的模擬信號進行采樣,將采集得到的音頻信號進行4 096點基2的FFT計算,并對信號加窗函數提高分辨率,另一單片機負責對信號的分析及控制顯示設備。此設計精確的測量了音頻信號的功率譜、周期性、失真度指標,達到較高的頻率分辨率,并能將測量結果通過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,同時實現對充電過程的監控,設計出一種用單片機控制的36 V鉛酸蓄電池充電電源。本電路采用反激式拓撲,連續電流工作模式,電源管理IC設計在電源的副邊,由ELAN公司的EM78P258N單片機模擬,是用可編程器件模擬電源管理IC,實現智能電源低成本化的一次成功嘗試,通過對單片機的軟件設計實現了充電電源的狀態顯示、充電時間控制、報警、過溫保護、過壓保護、過流保護等功能。本充電器真正的實現了鉛酸蓄電池的三段式充電過程,其最高輸出功率可達90 W,效率約85%,成本不到20元,具有很高的市場競爭力。 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.
上傳時間: 2013-11-16
上傳用戶:cepsypeng
以太網和CAN總線應用廣泛,但由于其通信協議不同,兩種總線器件間無法進行數據通信,因此,設計了基于CP2200與C8051F040的以太網總線與CAN總線接口轉換電路,并給出部分相關硬件電路與軟件設計分析。在保證數據完整和協議可靠的前提下,通過握手協議和簡化的以太網協議,不僅實現了以太網數據與CAN數據的轉發,同時還順利的解決了以太網的高速性與CAN的低速率沖突,以及兩者數據包之間的大小不同的矛盾。 Abstract: In the development of actual application, Ethernet and CAN bus are used very extensively. Owing to its various communication protocols, the communicating between two kinds of bus device can’t be carried out. Therefore, in order to solve this problem, the Ethernet-CAN bus interface circuit based on CP2200 and C8051F040 was designed in this paper, and part of the related hardware circuit and software design analysis were given. On the condition of data’s integrity and protocols’reliability, through the handshaking protocols and the simplified the Ethernet protocol, not only the data switching between CAN and Ethernet was realized, but also the differ in velocity and packet size was solved.
上傳時間: 2013-10-15
上傳用戶:Ants