What would happen if someone connected 24V to your12V circuits? If the power and ground lines were inadvertentlyreversed, would the circuits survive? Does yourapplication reside in a harsh environment, where the inputsupply can ring very high or even below ground? Evenif these events are unlikely, it only takes one to destroya circuit board.
上傳時間: 2013-10-26
上傳用戶:jackandlee
Specifying the right reference and applying it correctly isa more difficult task than one might first surmise, consideringthat references are only 2- or 3-terminal devices.Although the word “accuracy” is most often spoken inreference to references, it is dangerous to use this wordtoo freely because it can mean different things to differentpeople. Even more perplexing is the fact that a referenceclassified as a dog in one application is a panacea inanother. This application note will familiarize the readerwith the various aspects of reference “accuracy” andpresent some tips on extracting maximum performancefrom any reference.
標簽: 電壓基準
上傳時間: 2013-10-15
上傳用戶:liuwei6419
For a variety of reasons, it is desirable to charge batteriesas rapidly as possible. At the same time, overchargingmust be limited to prolong battery life. Such limitation ofovercharging depends on factors such as the choice ofcharge termination technique and the use of multi-rate/multi-stage charging schemes. The majority of batterycharger ICs available today lock the user into one fixedcharging regimen, with at best a limited number ofcustomization options to suit a variety of application needsor battery types. The LTC®1325 addresses these shortcomingsby providing the user with all the functionalblocks needed to implement a simple but highly flexiblebattery charger (see Figure 1) which not only addressesthe issue of charging batteries but also those of batteryconditioning and capacity monitoring.
上傳時間: 2013-10-19
上傳用戶:royzhangsz
Portable, battery-powered operation of electronic apparatushas become increasingly desirable. Medical, remotedata acquisition, power monitoring and other applicationsare good candidates for batteryoperation. In some circumstances,due to space, power or reliability considerations,it is preferable to operate the circuitry from a single 1.5Vcell. Unfortunately, a 1.5V supply eliminates almost alllinear ICs as design candidates. In fact, the LM10 opamp-reference and the LT®1017/LT1018 comparators arethe only IC gain blocks fully specifi ed for 1.5V operation.Further complications are presented by the 600mV dropof silicon transistors and diodes. This limitation consumesa substantial portion of available supply range, makingcircuit design diffi cult. Additionally, any circuit designedfor 1.5V operation mustfunction at end-of-life batteryvoltage, typically 1.3V. (See Box Section, “Componentsfor 1.5V Operation.”)
標簽: Circuitry Operation Single Cell
上傳時間: 2013-10-30
上傳用戶:hz07104032
為解決直流逆變交流的問題,有效地利用能源,讓電源輸出最大功率,設計了高性能的基于IR2101最大功率跟蹤逆變器,并以SPMC75F2413A單片機作為主控制器。高電壓、高速功率的MOSFET或IGBT驅動器IR2101采用高度集成的電平轉換技術,同時上管采用外部自舉電容上電,能夠穩定高效地驅動MOS管。該逆變器可以實現DC/AC的轉換,最大功率點的跟蹤等功能。實際測試結果表明,該逆變器系統具有跟蹤能力強,穩定性高,反應靈敏等特點,該逆變器不僅可應用于普通的電源逆變系統,而且可應用于光伏并網發電的逆變系統,具有廣泛的市場前景。 Abstract: To solve the problem of DC-AC inverter, and to utilize solar energy more efficiently, the design of maximum power point tracking inverter based on IR2101 was achieved with a high-performance, which can make the system output power maximum. SPMC75F2413A was adopted as main controller. IR2101 is a high voltage, high speed power MOSFET and IGBT driver. It adopted highly integrated voltage level transforming technology, and an external bootstrap capacitor was used, which could drive MOS tube efficiently and stably. Many functions are achieved in the system, such as DC/AC conversion, maximun power point tracking, etc. The actual test result shows that the inverter system has characteristics of strong tracking ability, high stability and reacting quickly. The design can not only be used in ordinary power inverter system, but also be used in photovoltaic power inverter system. The design has certain marketing prospects
上傳時間: 2013-11-17
上傳用戶:lliuhhui
Analog Inputs and Outputs in an S7 PLC are represented in the PLC as a 16-bit integer. Over the nominal span of the analog input or output, the value of this integer will range between - 27648 and +27648. However, it is easier to use the analog values if they are scaled to the same units and ranges as the process being controlled. This applications tip describes methods for scaling analog values to and from engineering units.
上傳時間: 2013-11-17
上傳用戶:3294322651
在理論分析循環碼編碼和譯碼基本原理的基礎上,提出了基于單片機系統的(24,16)循環碼軟件實現編碼、譯碼的方案。仿真結果表明(24,16)循環碼能有效地克服來自通訊信道的干擾,保證數據通信的可靠及系統的穩定,使誤碼率大幅度降低。本論文對(24,16)循環碼的研究結果表明,可以有效地降低錯誤概率和提高系統的吞吐量,實現糾錯僅需要在接收端增加有限的存儲空間和計算復雜度,具有一定的實用價值。 Abstract: Based on analyzing the theory of encoding and decoding of cyclic code, this paper showed the schemes of encoding and decoding of(24,16)cyclic code by the software and based on microcontroller. Simulation results show that using (24,16) cyclic codes can effectively overcome the interference from communication channel, ensure the reliability and stability of data communication systems, and reduce the bit error rate greatly. The results of this paper show that by using the (24,16) cyclic code, the error rate can be reduced and the system throughput can be improved. Meanwhile, the system only needs to enlarge limited storage space and computation the complexity at the receiving end to realize error correction. Thus the (24,16) cyclic code has a practical value.
上傳時間: 2013-11-09
上傳用戶:gaoliangncepu
利用單片機具有的智能程序控制的特點,設計了基于STC89C52單片機的"二極管特性測試器",可對二極管一般特性進行快速測試。通過穩定線性電流源給二極管加載恒定電流,然后由高精度模數轉換器測試其壓降,以此為基礎可判斷二極管好壞、檢測二極管極性和測試二極管伏安特性等,避免了用萬用表測試只能測得極性而不知其特性這一缺點。可用于電子設計制作過程中對二極管進行快速測試,以確定被測二極管是否滿足電路的設計要求。 Abstract: By making good use of the intelligent control function of the Micro Controller Unit (MCU), the diode trait tester was designed based on the STC89C52,which could be used to test the trait of a diode rapidly. By loading constant current to diode through the stable linear current source, and measuring the voltage drop of the diode by high-precision analogue-to-digital converter (ADC), it can judge whether the diode is good or not, distinguish the polarity of the diode, and test the trait that the diode, which can avoid the fault of using a multimeter can only measure the polarity but not the trait. This device can be used to test the trait of a diode quickly,and to make sure that whether a diode can be used in the electronic design or not.
上傳時間: 2013-11-13
上傳用戶:assef
Designing read/write device (RWD) units for industrial RF-Identification applications is strongly facilitated by the NXP Semiconductors HITAG Reader Chip HTRC110. All needed function blocks, like the antenna driver, modulator demodulator and antenna diagnosis unit, are integrated in the HTRC110. Therefore only a minimum number of additional passive components are required for a complete RWD. This Application Note describes how to design an industrial RF-Identification system with the HTRC110. The major focus is dimensioning of the antenna, all other external components including clock and power supply, as well as the demodulation principle and its implementatio
上傳時間: 2013-10-22
上傳用戶:zhengjian
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