Abstract: Most magnetic read head data sheets do not fully specify the frequency-dependent components andare often vague when specifying other key parameters. In some cases, the specifications of two very similarheads from two different manufacturers might be quite different in terms of parameters specified and omitted.The limitations in the data sheets make designing an optimum card reading system unnecessarily difficult andtime consuming. This document outlines a strategy to overcome the above shortcomings and offers guidelinesto overcome the noise issues.
上傳時間: 2013-11-13
上傳用戶:dysyase
This paper presents a space vector modulation(SVM)-based switching strategy for a three-level neutral point clamped (NPC) converter that is adapted as a STATCOM.
上傳時間: 2013-10-20
上傳用戶:zyt
設計了水聲信號發生系統中的功率放大電路,可將前級電路產生的方波信號轉換為正弦信號,同時進行濾波、功率放大,使其滿足換能器對輸入信號的要求。該電路以單片機AT89C52,集成6階巴特沃思低通濾波芯片MF6以及大功率運算放大器LM12為核心,通過標準RS232接口與PC進行通信,實現信號增益的程控調節,對干擾信號具有良好的抑制作用。經調試該電路工作穩定正常,輸出波形無失真,在輸出功率以及放大增益、波紋系數等方面均滿足設計要求。 This paper presented a design and implementation of underwater acoustic power amplifer. This circuit converted the rectangle signal generated by frontend circuit into the sine signal, then filtered and power amplification, it meets the requirements of the transducer.Included AT89C52, 6th order Butterworth filter MF6, hipower amplififier LM12.Communication with PC through the RS232 port. The signal gain is adjustable and could be remote controlled. It has a good inhibitory effect on the interference signal. After debugged, this circuit works stable, the output waveform has no distortion, it meets the design requirement in outprt power, amplifier gain and ripple factor.
上傳時間: 2013-11-20
上傳用戶:qwe1234
Radio Frequency Integrated Circuit Design I enjoyed reading this book for a number of reasons. One reason is that itaddresses high-speed analog design in the context of microwave issues. This isan advanced-level book, which should follow courses in basic circuits andtransmission lines. Most analog integrated circuit designers in the past workedon applications at low enough frequency that microwave issues did not arise.As a consequence, they were adept at lumped parameter circuits and often notcomfortable with circuits where waves travel in space. However, in order todesign radio frequency (RF) communications integrated circuits (IC) in thegigahertz range, one must deal with transmission lines at chip interfaces andwhere interconnections on chip are far apart. Also, impedance matching isaddressed, which is a topic that arises most often in microwave circuits. In mycareer, there has been a gap in comprehension between analog low-frequencydesigners and microwave designers. Often, similar issues were dealt with in twodifferent languages. Although this book is more firmly based in lumped-elementanalog circuit design, it is nice to see that microwave knowledge is brought inwhere necessary.Too many analog circuit books in the past have concentrated first on thecircuit side rather than on basic theory behind their application in communications.The circuits usually used have evolved through experience, without asatisfying intellectual theme in describing them. Why a given circuit works bestcan be subtle, and often these circuits are chosen only through experience. Forthis reason, I am happy that the book begins first with topics that require anintellectual approach—noise, linearity and filtering, and technology issues. Iam particularly happy with how linearity is introduced (power series). In therest of the book it is then shown, with specific circuits and numerical examples,how linearity and noise issues arise.
上傳時間: 2014-12-23
上傳用戶:han_zh
1.什么是CTP? CTP包括幾種含義: 脫機直接制版(Computer-to-plate) 在機直接制版(Computer-to-press) 直接印刷(Computer-to-paper/print) 數字打樣(Computer-to-proof) 普通PS版直接制版技術,即CTcP(Computer-to-conventional plate) 這里所論述的CTP系統是脫機直接制版(Computer-to-plate)。CTP就是計算機直接到印版,是一種數字化印版成像過程。CTP直接制版機與照排機結構原理相仿。起制版設備均是用計算機直接控制,用激光掃描成像,再通過顯影、定影生成直接可上機印刷的印版。計算機直接制版是采用數字化工作流程,直接將文字、圖象轉變為數字,直接生成印版,省去了膠片這一材料、人工拼版的過程、半自動或全自動曬版工序。
標簽: CTP
上傳時間: 2013-10-27
上傳用戶:baiom
In this paper, two types of MMIC voltage controlled oscillators have been successfully demonstrated. The first chip with single tuning diode shows the excellent tuning linearity. The second chip with two tuning diodes can improve the tuning bandwidth.
上傳時間: 2013-10-17
上傳用戶:xjz632
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
光伏發電是未來新能源發電重要方向之一,而光伏變流器是光伏發電系統的核心。介紹一種基于微網理念的光伏變流器設計。以該變流器為核心的光伏發電系統可以看做一個小型的微網系統。該系統能根據外部電網情況,工作于并網模式和離網模式。介紹了該系統的各個組成部件的設計以及變流器主電路部分器件的選型。最后,由實驗樣機進行測試。試驗結果驗證了電路拓撲結構及控制方案的可行性,也說明了系統參數設計方法的正確性。 Abstract: Solar Photovoltaic generation is an important direction of new energy power generation in the future,while photovoltaic converter is the core of photovoltaic generation system. This paper deals with a study on photovoltaic inverter based on the concept of microgrid. This paper describes a system whose core component is the photovoltaic inverter,can work on grid-connected mode or run independently according to the external situation. The paper simply describes the main components of the system. At last,the prototype was produced and tested. Test result has proved feasibility of circuit topology structure and controlling scheme and shown correctness of system parameters.Key words: PV inverter; microgrid; off-grid; storage battery
上傳時間: 2014-12-24
上傳用戶:Shaikh
This white paper raises some fundamental issues the design engineer should address before deciding upon a communication approach for a wireless network. As no universal wireless network solution exists, it should be custom tailored to suit the application demands. Defining your application communication characteristics is the key to ensure optimal communication reliability and resistance to interfering noise sources.
上傳時間: 2013-11-23
上傳用戶:zhichenglu
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