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1、CDS:correlateddoublesamplerVGA:variablegainamplifierAFE:AFE(ActiveFrontEnd)整流/回馈单元的功能.其主动的含义在丁,与传统的二极管或可控制硅整流技术相比,主动前端不再是被动地将交流转变成直流,而是具备了很多主动的控制功能。它不仅能消除高次谐波,提高功率因数,而且不受电网波动的影响,具有卓越的动态特性。ADC性能指标:直流性能:INL:积分非线性误差。指的是实际的传输特性与理想传输特性的在垂直方向上的最大差值,它表示了实际转移曲线偏离理想曲线的程度。INL=|(VD-VZERO)/VLSB-IDEAL-D|,其中0D2七D
2、NL:微分非线性误差。DNL=|(VD+1-Vd)/VLSB-IDEAL-1|,其中0DPowerSupplv(fordisplaypurposesonly).DVCC:Digitalvoltagelevel.&etunderConfigPowerSupply(fordisplaypurposesonly).Encode:ADCclockrate(N1SPS),sunderConfigFFT.Analog:CalculatedanalcginputfEquerinyMin:Minimumoutputcodeproducedbytheanaloginput.Max;Maximiunoutputc
3、odeprnduccdbytheanaloginput,Range:Thrrangeofthecodesproilutcdbytheanaloginput.Average:A7eragevalueofthecodes;maybeinterpretedasthecommonmcdcOffset:Thedifferencebetweentheaverageandtheidealincdi耳ncodevalue.F/S:Full-scalecaderinge,equalta2n,wherenisthenumberofbits.SamplerNumber成warnplusukccitermilledb
4、yFkICxmtiguraticn(ConfigFFT).频域信号(FFD;AVCC:Analogvoltagelevel,setunderConfigPowerSupply(fordisplaypurposesonly),DVCC:DigitalvoltagesetimJerConfigPowerSupply(forJsplaypurposescnly).Encode:ADCclockrate(MSPS),setunderConfigFFI.Analog:Cakulatidanaloginputfrequency(MHz).InIFaamplingappliestionstheanalogi
5、nputiscalculatedbacktothefirstNyquistNwthattheraimustbesetproperlyintheConfigFITmenu.SNR:SignaLto-noiseratio(dB),SNRFS:Signal-to-nois?ratiofullgk(dBFS).UDSNR:Userdefinedsignal-to-naiseratioidHjNF;Noisefigure(dB).SINAD:Sinabto-noiiieanddistortion(dB)_Funil:Levelofthefundanieutil(highesttone(ilHlS).Im
6、age:Leveofimsg?(nonhamonic)spur(dBt).NotethatimageisvalidonlywhenusingdeniultipkxedADC氤Second:Levdoftbcsecondharmonic(dBc)ofthefundamcnta.Third:LevtofthethirdharmonicidB。)otihefundamenTaJ.Fourth:Levelofthefourthharmonic(dBc)ofthefundamental.Fifth:Levelqfthefifthharmomt(dBc)ofthetuiiJamcntaLSixth:Lev
7、elofthesixthharmonic(dBc)oftheftmdainentaL腿Spur:Lg:oftheworstspurnotincludingthefintsixharmnines(dBr),THD:Totalharmonicdistortion(dBc).SFDR:Spviriovis-freedynamicran(JBc).NGistIloonLexelofthenistfloor(dBFS.Samples:Numberofsainplcstaken,determinedbyFFTconfiiirAoii,setunde-rConfigFFT.ADanalyzer能做的处理有:
8、1. HilberttransformI&Q输出peakhold:可计算几个采样里面的peak值。输出peakFFTdatapower/phase:把FFT信号转为power/phase信号。2. waveformanalysis:分析时域里的最大、最小、average。CCD工作波形:ADCAnalog为了检验该软件的计算能力,尝试使用excel生成两组数据,仿真ADC的真实输出数据。再把这个数据导入ADCAnalog中,看它的分析结果。例1:假定对一个14bitADC输入“频率0.1MHz,满幅值,2000个采样点”的正弦波,得到理想ADC在量化之后输出的数字序列。这个序列我使用EXCEL
9、来仿真生成,公式是“8192*SIN(2*PI()*A1)+8192”。把它生成的数据取整数,导入ADCAnalog中做FFT,生成下图:ChA!FTDtviciA304&1Drt=2013-&-1BTS二92D21SnpleFrejLienc/=13D11Hz.Sanpies二5CO01SKR-L.396dBSNMS-6JD8dSDTAD=-1困2JEeDID3MHzDfEg函=勺LM4E?5FoilFrenia&ricy=0.3NHrFs也Pcm=-7457iBFS临dBins-21Hrn2F盅=-20153街?|uiiDruweis9.57dDcHim4Fo宜统=30153H=b5Far
10、=-14.OTO超mKrn6Fewer-30,155皿二WcrstOtherFreuemc?=01IHrNbKCth-Powsr=-11-279dEBISNcise/Kz=三出.05IbfS,HiK”建#BinWNm-4SQfttBTSTH)-OHdi曜SFDK=3.822dB:软件默认以最大幅值的频率作为基频。可以手动修改成任意频率,修改后SNR等相关数值会重新计算。把基频修改成0.1MHz后见下图,可看出SNR、SNRFSSINAD、THD的值变了:ib?riD*vc*=U9lDtesZQl3-5-19Tirie=9:35JC5=mpFreiiericy=0OMic&知讪畦-ZOOCISM
11、X=-2.534dBsmr?=0H2dB51III二Ti口茸租官DCFrpqueniry=MUiDCFever=36.755dJfSKijcndfreiiiieiLeyD时IeFluidtwr=-11306-FSFajidFins=21Hurn2腿村=一明4强dBnH:3m3Fovr=3B51cBcHste司Fovsr-25448d3cHarn5Foiver-D舞dieHwn6Fm”=-Z5WEdBcSiDtlh*r-51Nfh,WotsiOtherFew叶=-14333dEFSNmm/Hz=-S?135cBFS/HzBlnJfcis?-=4b.?06dtFSTHU=5.201if,。5FIR=-3957dBc例2.对例1中的信号加入一个0.7MHz的噪声,同样用excel仿真生成2000个数据,公式“4000*SIN(2*PI()*C1)+8192+90*SIN(14*PI()*C1+1)。把数据导