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.
標(biāo)簽: 465 DN 超低功耗 升壓轉(zhuǎn)換器
上傳時(shí)間: 2013-11-23
上傳用戶:新手無憂
Handheld electronic devices play a key role in our everydaylives. Because dependability is paramount, handhelds arecarefully engineered with lightweight power sources forreliable use under normal conditions. But no amount ofcareful engineering can prevent the mistreatment theywill undergo at the hands of humans. For example, whathappens when a factory worker drops a bar code scanner,causing the battery to pop out? Such events areelectronically unpredictable, and importAnt data storedin volatile memory would be lost without some form ofsafety net—namely a short-term power holdup systemthat stores suffi cient energy to supply standby power untilthe battery can be replaced or the data can be stored inpermanent memory.
標(biāo)簽: 超級(jí)電容器 備用電源 手持設(shè)備
上傳時(shí)間: 2013-11-05
上傳用戶:coeus
光伏發(fā)電是未來新能源發(fā)電重要方向之一,而光伏變流器是光伏發(fā)電系統(tǒng)的核心。介紹一種基于微網(wǎng)理念的光伏變流器設(shè)計(jì)。以該變流器為核心的光伏發(fā)電系統(tǒng)可以看做一個(gè)小型的微網(wǎng)系統(tǒng)。該系統(tǒng)能根據(jù)外部電網(wǎng)情況,工作于并網(wǎng)模式和離網(wǎng)模式。介紹了該系統(tǒng)的各個(gè)組成部件的設(shè)計(jì)以及變流器主電路部分器件的選型。最后,由實(shí)驗(yàn)樣機(jī)進(jìn)行測試。試驗(yàn)結(jié)果驗(yàn)證了電路拓?fù)浣Y(jié)構(gòu)及控制方案的可行性,也說明了系統(tǒng)參數(shù)設(shè)計(jì)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
標(biāo)簽: 光伏 變流器 系統(tǒng)設(shè)計(jì)
上傳時(shí)間: 2014-12-24
上傳用戶:Shaikh
鎖定放大是微弱信號(hào)檢測的重要手段。基于相關(guān)檢測理論,利用開關(guān)電容的開關(guān)實(shí)現(xiàn)鎖定放大器中乘法器的功能,提出開關(guān)電容和積分器相結(jié)合以實(shí)現(xiàn)相關(guān)檢測的方法,并設(shè)計(jì)出一種鎖定放大器。該鎖定放大器將微弱信號(hào)轉(zhuǎn)化為與之相關(guān)的方波,通過后續(xù)電路得到正比于被測信號(hào)的直流電平,為后續(xù)采集處理提供方便。測量數(shù)據(jù)表明鎖定放大器前級(jí)可將10-6 A的電流轉(zhuǎn)換為10-1 V的電壓,后級(jí)通過帶通濾波器級(jí)聯(lián)可將信號(hào)放大1×105倍。該方法在降低噪聲的同時(shí),可對(duì)微弱信號(hào)進(jìn)行放大,線性度較高、穩(wěn)定性較好。 Abstract: Lock-in Amplifying(LIA)is one of importAnt means for weak signal detection. Based on cross-correlation detection theory, switch in the swithched capacitor was used as multiplier of LIA, and a new method of correlation detection was proposed combining swithched capacitor with integrator. A kind of LIA was designed which can convert the weak signal to square-wave, then DC proportional to measured signal was obtained through follow-up conditioning circuit, providing convenience for signal acquisition and processing. The measured data shows that the electric current(10-6 A) can be changed into voltage(10-1 V) by LIA, and the signal is magnified 1×105 times by cascade band-pass filter. The noise is suppressed and the weak signal is amplified. It has the advantages of good linearity and stability.
標(biāo)簽: 開關(guān)電容 鎖定放大器
上傳時(shí)間: 2013-11-29
上傳用戶:黑漆漆
When a system designer specifies a nonisolated dc/dc powermodule, considering the needed input voltage range isequally as importAnt as considering the required performanceattributes and features. Generally, nonisolated moduleshave either a narrow or a wide input voltage range. Narrowinputmodules typically have a nominal input voltage of3.3, 5, or 12 V. For systems that operate from a tightlyregulated input bus—such as those that do not use batterybackup—a narrow-input module is often adequate sincethe input remains fairly stable.Offering greater flexibility, wide-input modules operatewithin a range of 7 to 36 V, which includes the popular12- or 24-V industrial bus. This enables a single module tobe used for generating multiple voltages. These modulesare ideal for industrial controls, HVAC systems, vehicles,medical instrumentation, and other applications that usea loosely regulated distribution bus. In addition, systemspowered by a rectifier/battery charger with lead-acidbattery backup almost always require wide-input modules.System designers who choose power supplies may wantto take a close look at the latest generation of wide-inputdc/dc modules.
標(biāo)簽: Wide-input modules offer dc
上傳時(shí)間: 2014-12-24
上傳用戶:dragonhaixm
實(shí)時(shí)時(shí)鐘是微機(jī)保護(hù)裝置的重要部件,在討論P(yáng)CF8583結(jié)構(gòu)與功能的基礎(chǔ)上,提出采用dsPIC33F系列微處理器與串行I2C時(shí)鐘PCF8583的接口設(shè)計(jì)方案,給出了相應(yīng)的接口電路與軟件流程。該設(shè)計(jì)方案結(jié)構(gòu)簡單,可靠性高,開發(fā)周期短,具有一定的實(shí)用與參考價(jià)值。所設(shè)計(jì)的微機(jī)保護(hù)裝置已投入現(xiàn)場運(yùn)行,效果良好。 Abstract: Real-time clock chip is an importAnt part in microcomputer protection device.Based on discussing the structure and function of PCF8583,a new interface scheme which uses dsPIC33F microprocessor and serial clock chip(I2C)PCF8583is proposed.The method of the circuit design and the main software flow are introduced in this paper.The scheme has simple structure,higher reliability and shorter exploitation cycle,so has definite practicality or reference value.The microcomputer protection device has been put into operation with better effects.
標(biāo)簽: 8583 PCF 串行時(shí)鐘 中的應(yīng)用
上傳時(shí)間: 2013-11-18
上傳用戶:Thuan
氣壓是氣象監(jiān)測中的一個(gè)重要參數(shù),提出了一種氣壓數(shù)據(jù)采集模塊設(shè)計(jì)方案,該模塊采用數(shù)字氣壓傳感器MS5534B、MSP430單片機(jī)MSP430F2272和帶實(shí)時(shí)時(shí)鐘(RTC)64 KB鐵電存儲(chǔ)器。通過低功耗軟件設(shè)計(jì)方法以微安級(jí)整體平均功耗實(shí)現(xiàn)了氣壓數(shù)據(jù)的采集和存儲(chǔ),適合電池供電的連續(xù)高精度氣壓采集應(yīng)用。給出了模塊的軟硬件設(shè)計(jì)以及MS5534B的性能指標(biāo)和使用經(jīng)驗(yàn)。 Abstract: Air pressure is an importAnt parameter in weather monitor.This paper futs forward a new design scheme of low power-air pressure data acquisition module.The module uses a digital output barometer sensor MS5534B,MSP430 microcontroller MSP430F2272 and integrated RTC 64KB FRAM,precision air pressure measurement and storage chip.Another point of this module is low power consumption, so it is well suited for battery powered air pressure data acquisition applications. At the same time,the software and hardware deign of module is presented,And the speciaties and use notices of MS5534B are given.
上傳時(shí)間: 2014-12-27
上傳用戶:drink!
importAnt Notice SUNPLUS INNOVATION TECHNOLOGY INC. reserves the right to change this documentation without prior notice. Information provided by SUNPLUS INNOVATION TECHNOLOGY INC. is believed to be accurate and reliable. However, SUNPLUS INNOVATION TECHNOLOGY INC.makes no warranty for any errors which may appear in this document. Contact SUNPLUS INNOVATION TECHNOLOGY INC.to obtain the latest version of device specifications before placing your order. No responsibility is assumed by SUNPLUS INNOVATION TECHNOLOGY INC. for any infringement of patent or other rights of third parties which may result from its use. In addition, SUNPLUSIT products are not authorized for use as critical components in life support systems or aviation systems, where a malfunction or failure of the product may reasonably be expected to result in significant injury to the user, without the express written approval of SunplusIT
標(biāo)簽: SUNPLUSIT Q-Writer 編程工具 使用說明書
上傳時(shí)間: 2013-10-13
上傳用戶:brain kung
匯編器在微處理器的驗(yàn)證和應(yīng)用中舉足輕重,如何設(shè)計(jì)通用的匯編器一直是研究的熱點(diǎn)之一。本文提出了一種開放式的匯編器系統(tǒng)設(shè)計(jì)思想,在匯編語言與機(jī)器語言間插入中間代碼CMDL(code mapping description language)語言,打破匯編語言與機(jī)器語言的直接映射關(guān)系,由此建立起一套描述匯編語言與機(jī)器語言的開放式映射體系。基于此開放式映射體系開發(fā)了一套匯編器系統(tǒng),具有較高層次上的通用性和可移植性。【關(guān)鍵詞】指令集,CMDL,匯編器,開放式 Design of Retargetable Assembler System Liu Ling Feng Wen Nan Wang Ying Chun Jiang An Ping Ji Li Jiu IME of Peking University, 100871【摘要】An assembler plays a very importAnt role in the field of microprocessor verifications and applications, thus how to build a retargetable assembler system has been a hotspot in this field for long time. This paper presents a new method about the retargetable assembler system design.It provides a kind of language CMDL, code mapping description language. During the process of assembling, assembler languages are firstly translated to CMDL, and then mapped to the machine codes. In an other word, CMDL is inserted between assembler languages and machine codes during the translation procedure. As a medium code, CMDL has a lot of features, such as high extraction, strong descript capabilities. It can describe almost all attributes of assembler languages. By breaking the direct mapping relationship between assembler languages and machine codes, the complexities of machine codes are hided to the users, therefore, the new retargetable assembler system has higher retargetable level by converting the mapping from assembler languages and machine codes to assembler languages and CMDL, and implementationof it becomes easier. Based on the new mapping system structure, a retargetable assemblersystem is developed. It proved the whole system has good retargetability and implantability.【關(guān)鍵詞】instruction set, symbol table, assembler, lexical analysis, retargetability
上傳時(shí)間: 2013-10-10
上傳用戶:meiguiweishi
基于LabVIEW和單片機(jī)的空調(diào)溫度場測量系統(tǒng)的研究:室內(nèi)溫度是空調(diào)系統(tǒng)舒適性的重要指標(biāo),對(duì)其及時(shí)、準(zhǔn)確地測量顯得非常重要。介紹單片機(jī)AT89C51 和數(shù)字式、單總線型溫度傳感器DS18B20 組成矩形測量網(wǎng)絡(luò)采集空調(diào)室內(nèi)40 點(diǎn)溫度,LabVIEW作為開發(fā)平臺(tái),二者之間通過串口實(shí)現(xiàn)數(shù)據(jù)通信,利用LabVIEW強(qiáng)大的數(shù)據(jù)處理和顯示功能對(duì)采集的空調(diào)溫度場數(shù)據(jù)進(jìn)行實(shí)時(shí)處理、分析和顯示,詳細(xì)介紹了系統(tǒng)的硬件結(jié)構(gòu)和軟件模塊的設(shè)計(jì)方案。關(guān)鍵詞:單片機(jī);DS18B20 ;LabVIEW;串行通信 Abstract : Temperature is a very importAnt criterion of air condition system′s comfort , so it is very significant to measure it accurately and real timely. This paper int roduces a data acquisition system of measuring 40 point s temperature for air condition room based on single wire digital sensor DS18B20 and microcont roller AT89C51 which are composed of rectangle measuring meshwork. The data communication between LabVIEW and microcont roller is executed via serial port ,and the temperature field data of air condition room are processed analyzed and displayed on LabVIEW. The hardware and software modules are also given in detail.Keywords : single chip ;DS18B20 ;LabVIEW; serial communication
標(biāo)簽: LabVIEW 單片機(jī) 空調(diào) 溫度場
上傳時(shí)間: 2014-05-05
上傳用戶:KSLYZ
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