ADI-AD7176-2高速高分辨率模数转换(ADC)解决方案

ADIAD7176－2高速高分辨率模数转换(ADC)解决方案时间：2015-03-2709:52:12作者：ADI来源：中电网ADI公司的AD7176-2是适用于低带宽输入信号的高速高精度高分辨率Σ-Δ模数转换器(ADC),每路取样频率50kSPS(设定时间20us),输出数据速率5SPS到250kSPS,低速时分辨率增加,主要用在过程控制中的PLC/DCS模块,温度和压力测量,医疗和科学仪表以及色层分析.本文介绍了AD7176-2主要特性,功能框图,典型应用电路,以及评估板EVAL-AD7176-2SDZ主要特性,框图,电路图,材料清单和PCB设计文件图.TheAD7176-2isafastsettling,highlyaccurate,highresolution,multiplexedΣ-Δanalog-to-digitalconverter(ADC)forlowband-widthinputsignals.Itsinputscanbeconfiguredastwofullydifferentialorfourpseudodifferentialinputsviatheintegratedcrosspointmultiplexer.Anintegratedprecision,2.5V,lowdrift(2ppm/℃),bandgapinternalreference(withanoutputreferencebuffer)addsfunctionalityandreducestheexternalcomponentcount.Themaximumchannelscandatarateis50kSPS/channel(settlingtimeof20μs),resultinginfullysettleddatawith17noisefreebits.User-selectableoutputdataratesrangefrom5SPSto250kSPS.Theresolutionincreasesatlowerspeeds.TheAD7176-2offersthreekeydigitalfilters.Thefastsettlingsinc5+sinc1filtermaximizesthechannelscanrate.Thesinc3filtermaximizestheresolutionforsingle-channel,lowspeedapplications.For50Hzand60Hzenvironments,theAD7176-2specificfilterminimizesthesettlingtimesormaximizestherejectionofthelinefrequency.Theseenhancedfiltersenablesimultaneous50Hzand60Hzrejectionwitha27SPSoutputdatarate(withasettlingtimeof36ms).Systemoffsetandgainerrorscanbecorrectedonaperchannelbasis.Thisperchannelconfigurabilityextendstotheoutputdatarateusedforeachchannelwhenusingasinc5+sinc1filter.AllswitchingofthecrosspointmultiplexeriscontrolledbytheADCandcanbeconfiguredtoautomaticallycontrolanexternalmultiplexerviatheGPIOpins.Thespecifiedoperatingtemperaturerangeis−40℃to+105℃.TheAD7176-2ishousedina24-leadTSSOPpackage.AD7176-2主要特性:Fastandflexibleoutputrate—5SPSto250kSPSFastsettlingtime—20μsChannelscandatarateof50kSPS/channelPerformancespecifications17noisefreebitsat250kSPS20noisefreebitsat2.5kSPS22noisefreebitsat5SPSINL±2.5ppmofFSR85dBrejectionof50Hzand60Hzwith50mssettlingUser-configurableinputchannels2fullydifferentialor4pseudodifferentialCrosspointmultiplexerOn-chip2.5Vreference(drift2ppm/℃)Internaloscillator,externalcrystal,orexternalclockPowersupplySinglesupply:5VAVDD1,2Vto5VAVDD2andIOVDDOptionalsplitsupply:AVDD1andAVSS±2.5VCurrent:7.8mATemperaturerange:−40℃to+105℃3-or4-wireserialdigitalinterface(SchmitttriggeronSCLK)CRCerrorcheckingSPI,QSPI,MICROWIRE,andDSPcompatibleAD7176-2应用:Processcontrol:PLC/DCSmodulesTemperatureandpressuremeasurementMedicalandscientificmultichannelinstrumentationChromatography图1.AD7176-2功能框图图2.AD7176-2典型应用电路评估板EVAL-AD7176-2SDZTheEVAL-AD7176-2SDZevaluationkitfeaturestheAD7176-224-bit,250kSPSanalog-to-digitalconverter(ADC).A7Vto9Vexternalbenchtopsupplyisregulatedto5Vand3.3VtosupplytheAD7176-2andsupportallnecessarycomponents.TheEVAL-AD7176-2SDZboardconnectstotheUSBportofthePCbyconnectiontotheEVAL-SDP-CB1Zmotherboard.TheEVAL-AD7176-2SDZsoftwarefullyconfigurestheAD7176-2deviceregisterfunctionalityandprovidesdctimedomainanalysisintheformofwaveformgraphs,histograms,andassociatednoiseanalysisforADCperformanceevaluation.TheEVAL-AD7176-2SDZisanevaluationboardthatisdesignedtoallowtheusertoevaluatethefeaturesoftheADC.TheuserPCsoftwareexecutablecontrolstheAD7176-2overtheUSBthroughthesystemdemonstrationplatformboard(EVAL-SDP-CB1Z).评估板EVAL-AD7176-2SDZ主要特性:FullfeaturedevaluationboardfortheAD7176-2PCcontrolinconjunctionwiththesystemdemonstrationplatform(EVAL-SDP-CB1Z)PCsoftwareforcontrolanddataanalysis(timedomain)StandalonecapabilityONLINERESOURCESEvaluationKitContentsEVAL-AD7176-2SDZevaluationboardEvaluationsoftwareCDfortheAD7176-2DocumentsNeededAD7176-2datasheetEVAL-AD7176-2SDZ(UG-478)userguideRequiredSoftwareEVAL-AD7176-2SDZevaluationsoftwareEQUIPMENTNEEDEDEVAL-AD7176-2SDZevaluationboardEVAL-SDP-CB1ZsystemdemonstrationplatformExternal7Vto9VpowersupplyDCsignalsourceUSBcablePCrunningWindowswithUSB2.0port图3.评估板EVAL-AD7176-2SDZ框图图4.评估板EVAL-AD7176-2SDZ硬件连接图图5.评估板EVAL-AD7176-2SDZ电路图(1)图6.评估板EVAL-AD7176-2SDZ电路图(2)图7.评估板EVAL-AD7176-2SDZ电路图(3)图8.评估板EVAL-AD7176-2SDZ电路图(4)图9.评估板EVAL-AD7176-2SDZ电路图(5)评估板EVAL-AD7176-2SDZ材料清单:图10.评估板EVAL-AD7176-2SDZPCB设计图(1)图11.评估板EVAL-AD7176-2SDZPCB设计图(2):顶层图12.评估板EVAL-AD7176-2SDZPCB设计图(3):底层图12.评估板EVAL-AD7176-2SDZPCB设计图(3):1层图13.评估板EVAL-AD7176-2SDZPCB设计图(4):2层地线图14.评估板EVAL-AD7176-2SDZPCB设计图(5):3层电源/地线图15.评估板EVAL-AD7176-2SDZPCB设计图(6):4层AO-Electronics傲壹电子官网：中文网：