PCB methodologies originated in the United States.Units of measurement are therefore typically in Imperial units, not SI/metric units.
標(biāo)簽: 布局技術(shù)
上傳時(shí)間: 2014-01-07
上傳用戶:asdkin
Abstract: It may sound trite, but it is definitely true: the smart grid has the potential to completely transform the energyindustry. However, smart meters and grid management alone will not ensure the success of the smart grid. Unliketraditional IT networks, smart grids require consideration of energy measurement and security. To completely optimize thistechnology, smart grid designs must focus on energy measurement and security. This tutorial considers the benefits ofboth energy measurement and security and how they make machine-to-machine networks different from traditional IT.
標(biāo)簽: 電能計(jì)量 安全性 智能電網(wǎng)
上傳時(shí)間: 2013-10-29
上傳用戶:皇族傳媒
為提高電容測(cè)量精度,針對(duì)電容式傳感器的工作原理設(shè)計(jì)了基于PIC16LF874單片機(jī)電容測(cè)量模塊。簡(jiǎn)單闡述了電容測(cè)量電路的應(yīng)用背景和國(guó)內(nèi)外研究現(xiàn)狀,介紹了美國(guó)Microchip公司PIC16LF874單片機(jī)的特性。電容式傳感器輸出的動(dòng)態(tài)微弱電容信號(hào)通過(guò)PS021型電容數(shù)字轉(zhuǎn)換器把模擬量數(shù)據(jù)轉(zhuǎn)換成數(shù)字量數(shù)據(jù),所測(cè)數(shù)據(jù)由PIC16LF874單片機(jī)應(yīng)用程序進(jìn)行處理、顯示和保存。實(shí)驗(yàn)結(jié)果表明,固定電容標(biāo)稱值為10~20 pF 的測(cè)量值相對(duì)誤差在1%以內(nèi),同時(shí)也可知被測(cè)電容容值越大,測(cè)量值和標(biāo)稱值相對(duì)誤差越小。 Abstract: To improve the accuracy of capacitance measurement,aimed at the principle of work of mercury capacitance acceleration transducer,the design of micro capacitance measurement circuit is based on the key PIC16LF874 chip. Briefly discusses the application of the capacitance measuring circuit for the background and status of foreign researchers,focusing on the United States PIC16LF874 microcontroller features. Capacitive sensor outputed signal through the dynamics of weak PS021-chip capacitors (capacitancedigital converter) to convert analog data into digital data,the measured data from the PIC16LF874 microcontroller application process, display and preservation. Experimental results show that the fixed capacitor 10pF ~ 20pF nominal value of the measured value of relative error is within 1%,but also it canbe seen the value of the measured capacitance larger,measuring value and the nominal value of relative error smaller.
上傳時(shí)間: 2013-10-29
上傳用戶:wojiaohs
生活中許多目標(biāo)的高度和水平距離需要進(jìn)行測(cè)量。目前主要的測(cè)量方法,仍以傳統(tǒng)的皮尺丈量為主,測(cè)量效率不高,有時(shí)還很不方便,沒(méi)有技術(shù)成熟的數(shù)字式測(cè)高測(cè)距產(chǎn)品。以基本的數(shù)學(xué)方法為理論依據(jù),利用遙控小車做為載體,采用角度傳感器測(cè)量角度、霍爾傳感器測(cè)量水平距離等,通過(guò)單片機(jī)LM3S615進(jìn)行數(shù)據(jù)計(jì)算,實(shí)現(xiàn)了對(duì)待測(cè)目標(biāo)物體的高度、水平距離等數(shù)據(jù)的快速、精確和數(shù)字式的測(cè)量,高度測(cè)量精度可達(dá)99.06%,水平測(cè)量精度則可達(dá)98.06%。 Abstract: In our lives, the height and horizontal distance of some goals are needed to be measured. Because the currently used methods are still traditional tape-based measuring methods, and the measuring efficiency is low and inconvenient so some kinds of digital and portable measuring methods or instruments are needed. Based on the basic math theory, this paper designed and manufactured a portable, digital and remote controlled measuring mobile small vehicle, which assembled with angle measuring sensor for angle measurement and Hall sensor for horizontal distance measuring. MCU LM3S615 calculated the height and horizontal distance data gotten from these sensors. The measuring process is simple, the measuring results are more accurate and the measuring efficiency is higher than traditional measure instruments. The accuracy of height and distance measurement can reach 99.06% and 98.06%.
標(biāo)簽: ARM 單片機(jī) 自動(dòng)
上傳時(shí)間: 2013-10-30
上傳用戶:jackandlee
為提高溫度測(cè)量效率,降低系統(tǒng)的成本,擴(kuò)展傳輸距離,設(shè)計(jì)出一種新型溫度采集系統(tǒng)。單片機(jī)通過(guò)控制具有單總線方式的溫度傳感器DS18B20實(shí)現(xiàn)對(duì)溫度的測(cè)量,同時(shí)單片機(jī)通過(guò)控制具有單總線方式300~450MHz頻率范圍內(nèi)的MAX7044與MAX7033無(wú)線發(fā)射與接收芯片實(shí)現(xiàn)溫度數(shù)據(jù)的無(wú)線傳輸。與傳統(tǒng)溫度采集系統(tǒng)相比,該系統(tǒng)利用單總線方式連接,采用無(wú)線傳輸方式實(shí)現(xiàn)遠(yuǎn)距離通信,易于系統(tǒng)的集成與擴(kuò)展。實(shí)驗(yàn)結(jié)果表明,該系統(tǒng)結(jié)構(gòu)簡(jiǎn)單、方便移植,能夠同時(shí)實(shí)現(xiàn)多達(dá)上百點(diǎn)溫度的測(cè)量與500m范圍的傳輸。 Abstract: To improve the temperature measurement efficiency and reduce system cost,expansion of transmission distance,a new type of temperature acquisition system is designed.Microcontroller controlled temperature sensor DS18B20which has a single-bus achieves temperature measurement,while microcontroller by controlled the MAX7044and MAX7033chip with a single-bus and having300~450MHz radiofrequency to achieve the wireless transmission of temperature data.Compared with conventional temperature acquisition system,the system uses single-bus connected,and uses wireless transmission means to achieve long-distance communications,easy-to-system integration and expansion.The experimental results show that the system is simple,convenient transplantation,and can be implemented in as many as a hundred-point temperature measure-ment and the transmission range of500meters.
標(biāo)簽: 單總線 無(wú)線溫度 采集 系統(tǒng)設(shè)計(jì)
上傳時(shí)間: 2013-10-29
上傳用戶:515414293
設(shè)計(jì)一種基于P89V51RD2的功率因數(shù)測(cè)量?jī)x,采用光電隔離器和專用數(shù)碼管驅(qū)動(dòng)器。該測(cè)量?jī)x是以增強(qiáng)型單片機(jī)P89V51RD2為核心,大大簡(jiǎn)化系統(tǒng)硬件設(shè)計(jì)。而軟件部分采用模塊化設(shè)計(jì)思想,采用中值濾波和小數(shù)補(bǔ)償算法,實(shí)現(xiàn)功率因數(shù)的高精度測(cè)量。實(shí)驗(yàn)測(cè)試表明,該功率因數(shù)測(cè)量?jī)x測(cè)量精度高,運(yùn)行穩(wěn)定可靠。 Abstract: A power-factor measurement instrument based on P89V51RD2is designed,which uses optical coupler and specific LED drive chip.The power factor measurement instrument uses P89V51RD2as a core of which greatly simplifies the system design.Furthermore,modularization software is developed in detail.The high precision power-factor measuring system is realized by the center value filter and fractional compensation algorithm.Experiments manifests that the power- factor measurement instrument is high precision,steady and reliable.
上傳時(shí)間: 2014-12-27
上傳用戶:CHINA526
該系統(tǒng)由單片機(jī)89S52控制模塊,程控寬帶放大模塊,整形模塊,F(xiàn)PGA內(nèi)頻率、相位差測(cè)量模塊等構(gòu)成,采用等精度測(cè)頻法測(cè)出頻率和周期,可測(cè)量有效值為0.01~5V,頻率范圍1Hz~20MHz信號(hào)的頻率、周期信號(hào),精度高達(dá)10-6。采用計(jì)數(shù)法測(cè)量相位差,該系統(tǒng)可測(cè)量有效值0.5~5V,頻率10Hz~100kHz信號(hào)的相位差,精度為1°。系統(tǒng)功能由按鍵控制,測(cè)量結(jié)果實(shí)時(shí)顯示,人機(jī)界面友好。 Abstract: The system consists of the following functional blocks:89S52microcontroller controlling module,programmable amplifier module,comparator module,frequency and phase difference testing module in the FPGA.The system use the equal accuracy frequency-examining technique it measures frequency and circle of signal which its ranges is from1Hz to20MHz and the amplitude of which its range is from0.01Vrms to5Vrms,precision is up to10-6.Using of count method,the system detects the phase difference of signal,the amplitude of whic its range is from0.5Vrms to5Vrms and the frequency of which its ranges is from10Hz to100kHz,precision is up to1°,The system functions is controlled by certain keys,measurement results are displayed in real-time and it is friendly interface.
標(biāo)簽: 89S52 單片機(jī) 多功能 計(jì)數(shù)器
上傳時(shí)間: 2013-11-04
上傳用戶:CHINA526
以89S52單片機(jī)和EP1C6Q240C8型FPGA為控制核心的多功能計(jì)數(shù)器,是由峰值檢波、A/D轉(zhuǎn)換、程控放大、比較整形、移相網(wǎng)絡(luò)部分組成,可實(shí)現(xiàn)測(cè)量正弦信號(hào)的頻率、周期和相位差的功能。多功能計(jì)數(shù)器采用等精度的測(cè)量方法,可實(shí)現(xiàn)頻率為1Hz~10MHz、幅度為0.01~5Vrms的正弦信號(hào)的精確測(cè)頻,以及頻率為10Hz~100kHz、幅度為0.5~5Vrms的正弦信號(hào)精確測(cè)相。液晶顯示器能夠?qū)崟r(shí)顯示當(dāng)前信號(hào)的頻率、周期和相位差。該多功能計(jì)數(shù)器精度高,界面友好,實(shí)用性強(qiáng)。 Abstract: A multi-function counter,which uses89S52MCU and EP1C6Q240C8FPGA as a control core,consists of peak detector,A/D conversion,program-controlled amplification,compared shaping and phase-shifting network part.The counter measures the frequency,period and phase of sinusoidal signal.With the equal precision method,the multi-function counter achieves the precise frequency measurement of the sinusoidal signal which its frequency is from1Hz to10MHz,its amplitude is from0.01Vrms to5Vrms,as well as the accurate phase measurement of the sinusoidal signal which its frequency is from10Hz to100kHz,its amplitude is from0.5Vrms to5Vrms.The LCD monitor real-time displays the frequency,period and phase difference of current signal.The multi-function counter features high precision,friendly interface,and strong practical.
標(biāo)簽: FPGA 單片機(jī) 多功能 計(jì)數(shù)器
上傳時(shí)間: 2013-11-15
上傳用戶:gy592333
提出一種基于C8051F040的炮塔方位角測(cè)試系統(tǒng)的設(shè)計(jì)方案,給出測(cè)試系統(tǒng)的各個(gè)模塊軟硬件設(shè)計(jì)。炮塔方位角測(cè)試系統(tǒng)集數(shù)據(jù)采集,數(shù)據(jù)傳輸和數(shù)據(jù)顯示等功能于一體,實(shí)現(xiàn)了炮塔方位角裝置的離線檢測(cè)。系統(tǒng)軟件采用C51編寫(xiě),對(duì)單片機(jī)進(jìn)行有效電源管理,保證了系統(tǒng)的穩(wěn)定性,可靠性。 Abstract: This paper puts forwards a design of artillery position system based on C8051F040,describes all modules hardware and software design of measurement system.The system has the function of information collection,transmission,and display.It can measure artillery position system in offline.The system software using C51can manage the power of single chip microcomputer,guarantee the stability,reliability.
標(biāo)簽: C8051F040 方位角 測(cè)試系統(tǒng)
上傳時(shí)間: 2014-12-27
上傳用戶:7891
介紹了一種基于C8051F020單片機(jī)的多路壓力測(cè)量?jī)x。該測(cè)量?jī)x選用電阻應(yīng)變式壓力傳感器采集壓力信號(hào),并經(jīng)放大電路處理后送入C8051F020單片機(jī),再由C8051F020單片機(jī)內(nèi)部的A/D轉(zhuǎn)換器將采集到的壓力信號(hào)進(jìn)行模數(shù)轉(zhuǎn)化,然后分別對(duì)數(shù)據(jù)進(jìn)行存儲(chǔ)和顯示。該測(cè)量?jī)x能測(cè)量6路壓力信號(hào),并且各測(cè)量點(diǎn)都能單獨(dú)檢測(cè)和設(shè)置。由于采用了C8051F020單片機(jī),簡(jiǎn)化了硬件電路,增強(qiáng)了抗干擾能力,使得測(cè)量?jī)x具有測(cè)量精度高,沖擊小等特點(diǎn)。 Abstract: A measurement apparatus for multi-channel pressure based on single chip microcomputer is introduced.It can measure 6 channels signal of the pressure,and the pressure measure points can be detection and located individually.The pressure signal sampling is obtained by resistor stress-type pressure sensors,the digital signals of 6 channels are collected through amplifying and adjustment circuit of pressure signals and internal integrated A/D converter of MCU.Finally,and it realizes the function to store and display data separately.C8051F020 was used to made hardware circuit simple,and it also enhanced the anti-interference ability.It features high precision and little impact.
標(biāo)簽: C8051F020 單片機(jī) 多路 壓力
上傳時(shí)間: 2013-11-16
上傳用戶:yare
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