外文翻译----数字温湿度传感器(sht 1x sht 7x)

附录三外文翻译外文资料SHT1X/SHT7XHUMIDITYTEMPERATURESENSORRELATIVEHUMIDITYANDTEMPERATURESENSORSDEWPOINTFULLYCALIBRATED,DIGITALOUTPUTEXCELLENTLONGTERMSTABILITYNOEXTERNALCOMPONENTSREQUIREDULTRALOWPOWERCONSUMPTIONSURFACEMOUNTABLEOR4PINFULLYINTERCHANGEABLESMALLSIZEAUTOMATICPOWERDOWNSHT1X/SHT7XPRODUCTSUMMARYTHESHTXXISASINGLECHIPRELATIVEHUMIDITYANDTEMPERATUREMULTISENSORMODULECOMPRISINGACALIBRATEDDIGITALOUTPUTAPPLICATIONOFINDUSTRIALCMOSPROCESSESWITHPATENTEDMICROMACHININGCMOSENSTECHNOLOGYENSURESHIGHESTRELIABILITYANDEXCELLENTLONGTERMSTABILITYTHEDEVICEINCLUDESACAPACITIVEPOLYMERSENSINGELEMENTFORRELATIVEHUMIDITYANDABANDGAPTEMPERATURESENSORBOTHARESEAMLESSLYCOUPLEDTOA14BITANALOGTODIGITALCONVERTERANDASERIALINTERFACECIRCUITONTHESAMECHIPTHISRESULTSINSUPERIORSIGNALQUALITY,AFASTRESPONSETIMEANDINSENSITIVITYTOEXTERNALDISTURBANCESEMCATAVERYCOMPETITIVEPRICEEACHSHTXXISINDIVIDUALLYCALIBRATEDINAPRECISIONHUMIDITYCHAMBERWITHACHILLEDMIRRORHYGROMETERASREFERENCETHECALIBRATIONCOEFFICIENTSAREPROGRAMMEDINTOTHEOTPMEMORYTHESECOEFFICIENTSAREUSEDINTERNALLYDURINGMEASUREMENTSTOCALIBRATETHESIGNALSFROMTHESENSORSTHE2WIRESERIALINTERFACEANDINTERNALVOLTAGEREGULATIONALLOWSEASYANDFASTSYSTEMINTEGRATIONITSTINYSIZEANDLOWPOWERCONSUMPTIONMAKESITTHEULTIMATECHOICEFOREVENTHEMOSTDEMANDINGAPPLICATIONSTHEDEVICEISSUPPLIEDINEITHSURFACEMOUNTABLELCCLEADLESSCHIPCARRIERORASAPLUGGABLE4PINSINGLEINLINETYPEPACKAGECUSTOMERSPECIFICPACKAGINGOPTIONSMAYBEAVAILABLEONREQUESTAPPLICATIONS_HVAC_AUTOMOTIVE_CONSUMERGOODS_WEATHERSTATIONS_HUMIDIFIERS_DEHUMIDIFIERS_TESTMEASUREMENT_DATALOGGING_AUTOMATION_WHITEGOODS_MEDICAL2INTERFACESPECIFICATIONSFIGURE2TYPICALAPPLICATIONCIRCUIT21POWERPINSTHESHTXXREQUIRESAVOLTAGESUPPLYBETWEEN24AND55VAFTERPOWERUPTHEDEVICENEEDS11MSTOREACHITS“SLEEP”STATENOCOMMANDSSHOULDBESENTBEFORETHATTIMEPOWERSUPPLYPINSVDD,GNDMAYBEDECOUPLEDWITHA100NFCAPACITOR22SERIALINTERFACEBIDIRECTIONAL2WIRETHESERIALINTERFACEOFTHESHTXXISOPTIMIZEDFORSENSORREADOUTANDPOWERCONSUMPTIONANDISNOTCOMPATIBLEWITHI2CINTERFACES,SEEFAQFORDETAILS221SERIALCLOCKINPUTSCKTHESCKISUSEDTOSYNCHRONIZETHECOMMUNICATIONBETWEENAMICROCONTROLLERANDTHESHTXXSINCETHEINTERFACECONSISTSOFFULLYSTATICLOGICTHEREISNOMINIMUMSCKFREQUENCY222SERIALDATADATATHEDATATRISTATEPINISUSEDTOTRANSFERDATAINANDOUTOFTHEDEVICEDATACHANGESAFTERTHEFALLINGEDGEANDISVALIDONTHERISINGEDGEOFTHESERIALCLOCKSCKDURINGTRANSMISSIONTHEDATALINEMUSTREMAINSTABLEWHILESCKISHIGHTOAVOIDSIGNALCONTENTIONTHEMICROCONTROLLERSHOULDONLYDRIVEDATALOWANEXTERNALPULLUPRESISTOREG10KISREQUIREDTOPULLTHESIGNALHIGHSEEFIGURE2PULLUPRESISTORSAREOFTENINCLUDEDINI/OCIRCUITSOFMICROCONTROLLERSSEETABLE5FORDETAILEDIOCHARACTERISTICS223SENDINGACOMMANDTOINITIATEATRANSMISSION,A“TRANSMISSIONSTART”SEQUENCEHASTOBEISSUEDITCONSISTSOFALOWERINGOFTHEDATALINEWHILESCKISHIGH,FOLLOWEDBYALOWPULSEONSCKANDRAISINGDATAAGAINWHILESCKISSTILLHIGHFIGURE3“TRANSMISSIONSTART“SEQUENCETHESUBSEQUENTCOMMANDCONSISTSOFTHREEADDRESSBITSONLY“000”ISCURRENTLYSUPPORTEDANDFIVECOMMANDBITSTHESHTXXINDICATESTHEPROPERRECEPTIONOFACOMMANDBYPULLINGTHEDATAPINLOWACKBITAFTERTHEFALLINGEDGEOFTHE8THSCKCLOCKTHEDATALINEISRELEASEDANDGOESHIGHAFTERTHEFALLINGEDGEOFTHE9THSCKCLOCK224MEASUREMENTSEQUENCERHANDTAFTERISSUINGAMEASUREMENTCOMMAND00000101FORRH,00000011FORTEMPERATURETHECONTROLLERHASTOWAITFORTHEMEASUREMENTTOCOMPLETETHISTAKESAPPROXIMATELY11/55/210MSFORA8/12/14BITMEASUREMENTTHEEXACTTIMEVARIESBYUPTO15WITHTHESPEEDOFTHEINTERNALOSCILLATORTOSIGNALTHECOMPLETIONOFAMEASUREMENT,THESHTXXPULLSDOWNTHEDATALINEANDENTERSIDLEMODETHECONTROLLERMUSTWAITFORTHIS“DATAREADY”SIGNALBEFORERESTARTINGSCKTOREADOUTTHEDATAMEASUREMENTDATAISSTOREDUNTILREADOUT,THEREFORETHECONTROLLERCANCONTINUEWITHOTHERTASKSANDREADOUTASCONVENIENTTWOBYTESOFMEASUREMENTDATAANDONEBYTEOFCRCCHECKSUMWILLTHENBETRANSMITTEDTHEUCMUSTACKNOWLEDGEEACHBYTEBYPULLINGTHEDATALINELOWALLVALUESAREMSBFIRST,RIGHTJUSTIFIEDEGTHE5THSCKISMSBFORA12BITVALUE,FORA8BITRESULTTHEFIRSTBYTEISNOTUSEDCOMMUNICATIONTERMINATESAFTERTHEACKNOWLEDGEBITOFTHECRCDATAIFCRC8CHECKSUMISNOTUSEDTHECONTROLLERMAYTERMINATETHECOMMUNICATIONAFTERTHEMEASUREMENTDATLSBBYKEEPINGACKHIGHTHEDEVICEAUTOMATICALLYRETURNSTOSLEEPMODEAFTERTHEMEASUREMENTANDCOMMUNICATIONHAVEENDEDWARNINGTOKEEPSELFHEATINGBELOW01CTHESHTXXSHOULDNOTBEACTIVEFORMORETHAN10OFTHETIMEEGMAX2MEASUREMENTS/SECONDFOR12BITACCURACY225CONNECTIONRESETSEQUENCEIFCOMMUNICATIONWITHTHEDEVICEISLOSTTHEFOLLOWINGSIGNALSEQUENCEWILLRESETITSSERIALINTERFACEWHILELEAVINGDATAHIGH,TOGGLESCK9ORMORETIMESTHISMUSTBEFOLLOWEDBYA“TRANSMISSIONSTART”SEQUENCEPRECEDINGTHENEXTCOMMANDTHISSEQUENCERESETSTHEINTERFACEONLYTHESTATUSREGISTERPRESERVESITSCONTENTFIGURE4CONNECTIONRESETSEQUENCE226CRC8CHECKSUMCALCULATIONTHEWHOLEDIGITALTRANSMISSIONISSECUREDBYA8BITCHECKSUMITENSURESTHATANYWRONGDATACANBEDETECTEDANDELIMINATEDPLEASECONSULTAPPLICATIONNOTE“CRC8CHECKSUMCALCULATION”FORINFORMATIONONHOWTOCALCULATETHECRC23STATUSREGISTERSOMEOFTHEADVANCEDFUNCTIONSOFTHESHTXXAREAVAILABLETHROUGHTHESTATUSREGISTERTHEFOLLOWINGSECTIONGIVESABRIEFOVERVIEWOFTHESEFEATURESAMOREDETAILEDDESCRIPTIONISAVAILABLEINTHEAPPLICATIONNOTE“STATUSREGISTERFIGURE7STATUSREGISTERWRITEFIGURE8STATUSREGISTERREAD231MEASUREMENTRESOLUTIONTHEDEFAULTMEASUREMENTRESOLUTIONOF14BITTEMPERATUREAND12BITHUMIDITYCANBEREDUCEDTO12AND8BITTHISISESPECIALLYUSEFULINHIGHSPEEDOREXTREMELOWPOWERAPPLICATIONS232ENDOFBATTERYTHE“ENDOFBATTERY”FUNCTIONDETECTSVDDVOLTAGESBELOW247VACCURACYIS005V233HEATERANONCHIPHEATINGELEMENTCANBESWITCHEDONITWILLINCREASETHETEMPERATUREOFTHESENSORBY515C927FPOWERCONSUMPTIONWILLINCREASEBY8MA5VAPPLICATIONSBYCOMPARINGTEMPERATUREANDHUMIDITYVALUESBEFOREANDAFTERSWITCHINGONTHEHEATER,PROPERFUNCTIONALITYOFBOTHSENSORSCANBEVERIFIEDINHIGH95RHRHENVIRONMENTSHEATINGTHESENSORELEMENTWILLPREVENTCONDENSATION,IMPROVERESPONSETIMEANDACCURACYWARNINGWHILEHEATEDTHESHTXXWILLSHOWHIGHERTEMPERATURESANDALOWERRELATIVEHUMIDITYTHANWITHNOHEATING3CONVERTINGOUTPUTTOPHYSICALVALUES31RELATIVEHUMIDITYTOCOMPENSATEFORTHENONLINEARITYOFTHEHUMIDITYSENSORANDTOOBTAINTHEFULLACCURACYITISRECOMMENDEDTOCONVERTTHEREADOUTWITHTHEFOLLOWINGFORMULA1RHLINEARC1C2SORHC32TABLE6HUMIDITYCONVERSIONCOEFFICIENTSTABLE7TEMPERATURECOMPENSATIONCOEFFICIENTTHEHUMIDITYSENSORHASNOSIGNIFICANTVOLTAGEDEPENDENCYFIGURE10CONVERSIONFROMSORHTORELATIVEHUMIDITY311HUMIDITYSENSORRH/TEMPERATURECOMPENSATIONFORTEMPERATURESSIGNIFICANTLYDIFFERENTFROM25C77FTHETEMPERATURECOEFFICIENTOFTHERHSENSORSHOULDBECONSIDEREDRHTRUETC25T1T2SORHRHLINEAR32TEMPERATURETHEBANDGAPPTATPROPORTIONALTOABSOLUTETEMPERATURETEMPERATURESENSORISVERYLINEARBYDESIGNUSETHEFOLLOWINGFORMULATOCONVERTFROMDIGITALREADOUTTOTEMPERATURETEMPERATURED1D2SOTTABLE8TEMPERATURECONVERSIONCOEFFICIENTSFORIMPROVEDACCURACIESINEXTREMETEMPERATURESWITHMORECOMPUTATIONINTENSECONVERSIONFORMULASSEEAPPLICATIONNOTE“RHANDTEMPERATURENONLINEARITYCOMPENSATION33DEWPOINTSINCEHUMIDITYANDTEMPERATUREAREBOTHMEASUREDONTHESAMEMONOLITHICCHIP,THESHTXXALLOWSSUPERBDEWPOINTMEASUREMENTSSEEAPPLICATIONNOTE“DEWPOINTCALCULATION”FORMORE4APPLICATIONSINFORMATION41OPERATINGANDSTORAGECONDITIONSFIGURE11RECOMMENDEDOPERATINGCONDITIONSCONDITIONSOUTSIDETHERECOMMENDEDRANGEMAYTEMPORARILYOFFSETTHERHSIGNALUPTO3RHAFTERRETURNTONORMALCONDITIONSITWILLSLOWLYRETURNTOWARDSCALIBRATIONSTATEBYITSELFSEE43“RECONDITIONINGPROCEDURE”TOACCELERATETHISPROCESSPROLONGEDEXPOSURETOEXTREMECONDITIONSMAYACCELERATEAGEING42EXPOSURETOCHEMICALSCHEMICALVAPORSMAYINTERFEREWITHTHEPOLYMERLAYERSUSEDFORCAPACITIVEHUMIDITYSENSORSTHEDIFFUSIONOFCHEMICALSINTOTHEPOLYMERMAYCAUSEASHIFTINBOTHOFFSETANDSENSITIVITYINACLEANENVIRONMENTTHECONTAMINANTSWILLSLOWLYOUTGASTHERECONDITIONINGPROCEDUREDESCRIBEDBELOWWILLACCELERATETHISPROCESSHIGHLEVELSOFPOLLUTANTSMAYCAUSEPERMANENTDAMAGETOTHESENSINGPOLYMER43RECONDITIONINGPROCEDURETHEFOLLOWINGRECONDITIONINGPROCEDUREWILLBRINGTHESENSORBACKTOCALIBRATIONSTATEAFTEREXPOSURETOEXTREMECONDITIONSORCHEMICALVAPORS8090C176194FAT74RHFOR48HREHYDRATION44TEMPERATUREEFFECTSTHERELATIVEHUMIDITYOFAGASSTRONGLYDEPENDSONITSTEMPERATUREITISTHEREFOREESSENTIALTOKEEPHUMIDITYSENSORSATTHESAMETEMPERATUREASTHEAIROFWHICHTHERELATIVEHUMIDITYISTOBEMEASUREDIFTHESHTXXSHARESAPCBWITHELECTRONICCOMPONENTSTHATGIVEOFFHEATITSHOULDBEMOUNTEDFARAWAYANDBELOWTHEHEATSOURCEANDTHEHOUSINGMUSTREMAINWELLVENTILATEDTOREDUCEHEATCONDUCTIONCOPPERLAYERSBETWEENTHESHT1XANDTHERESTOFTHEPCBSHOULDBEMINIMIZEDANDASLITMAYBEMILLEDINBETWEENSEEFIGURE1345MEMBRANESAMEMBRANEMAYBEUSEDTOPREVENTDIRTFROMENTERINGTHEHOUSINGANDTOPROTECTTHESENSORITWILLALSOREDUCEPEAKCONCENTRATIONSOFCHEMICALVAPORSFOROPTIMALRESPONSETIMESAIRVOLUMEBEHINDTHEMEMBRANEMUSTBEKEPTTOAMINIMUMFORTHESHT1XPACKAGESENSIRIONRECOMMENDSTHESF1FILTERCAPFOROPTIMALIP67PROTECTION46LIGHTTHESHTXXISNOTLIGHTSENSITIVEPROLONGEDDIRECTEXPOSURETOSUNSHINEORSTRONGUVRADIATIONMAYAGETHEHOUSING47MATERIALSUSEDFORSEALING/MOUNTINGMANYMATERIALSABSORBHUMIDITYANDWILLACTASABUFFER,INCREASINGRESPONSETIMESANDHYSTERESISMATERIALSINTHEVICINITYOFTHESENSORMUSTTHEREFOREBECAREFULLYCHOSENRECOMMENDEDMATERIALSAREALLMETALS,LCP,POMDELRIN,PTFETEFLON,PE,PEEK,PP,PB,PPS,PSU,PVDF,PVFFORSEALINGANDGLUINGUSESPARINGLYHIGHFILLEDEPOXYFORELECTRONICPACKAGINGEGGLOBTOP,UNDERFILL,ANDSILICONEOUTGASSINGOFTHESEMATERIALSMAYALSOCONTAMINATETHESHTXXCF42STOREWELLVENTILATEDAFTERMANUFACTURINGORBAKEAT50CFOR24HTOOUTGASCONTAMINANTSBEFOREPACKING48WIRINGCONSIDERATIONSANDSIGNALINTEGRITYCARRYINGTHESCKANDDATASIGNALPARALLELANDINCLOSEPROXIMITYEGINWIRESFORMORETHAN10CMMAYRESULTINCROSSTALKANDLOSSOFCOMMUNICATIONTHISMAYBERESOLVEDBYROUTINGVDDAND/ORGNDBETWEENTHETWODATASIGNALSPLEASESEETHEAPPLICATIONNOTE“ESD,LATCHUPANDEMC”FORMOREINFORMATIONPOWERSUPPLYPINSVDD,GNDSHOULDBEDECOUPLEDWITHA100NFCAPACITORIFWIRESAREUSED49ESDELECTROSTATICDISCHARGEESDIMMUNITYISQUALIFIEDACCORDINGTOMILSTD883E,METHOD3015HUMANBODYMODELAT2KVLATCHUPIMMUNITYISPROVIDEDATAFORCECURRENTOF100MAWITHTAMB80CACCORDINGTOJEDEC17SEEAPPLICATIONNOTE“ESD,LATCHUPANDEMC”FORMOREINFORMATION5IMPORTANTNOTICES51WARNING,PERSONALINJURYDONOTUSETHISPRODUCTASSAFETYOREMERGENCYSTOPDEVICESORINANYOTHERAPPLICATIONWHEREFAILUREOFTHEPRODUCTCOULDRESULTINPERSONALINJURYFAILURETOCOMPLYWITHTHESEINSTRUCTIONSCOULDRESULTINDEATHORSERIOUSINJURYSHOULDBUYERPURCHASEORUSESENSIRIONAGPRODUCTSFORANYSUCHUNINTENDEDORUNAUTHORIZEDAPPLICATION,BUYERSHALLINDEMNIFYANDHOLDSENSIRIONAGANDITSOFFICERS,EMPLOYEES,SUBSIDIARIES,AFFILIATESANDDISTRIBUTORSHARMLESSAGAINSTALLCLAIMS,COSTS,DAMAGESANDEXPENSES,ANDREASONABLEATTORNEYFEESARISINGOUTOF,DIRECTLYORINDIRECTLY,ANYCLAIMOFPERSONALINJURYORDEATHASSOCIATEDWITHSUCHUNINTENDEDORUNAUTHORIZEDUSE,EVENIFSUCHCLAIMALLEGESTHATSENSIRIONAGWASNEGLIGENTREGARDINGTHEDESIGNORMANUFACTUREOFTHEPART52ESDPRECAUTIONSTHEINHERENTDESIGNOFTHISCOMPONENTCAUSESITTOBESENSITIVETOELECTROSTATICDISCHARGEESDTOPREVENTESDINDUCEDDAMAGEAND/ORDEGRADATION,TAKENORMALESDPRECAUTIONSWHENHANDLINGTHISPRODUCTSEEAPPLICATIONNOTE“ESD,LATCHUPANDEMC”FORMOREINFORMATION53WARRANTYSENSIRIONAGMAKESNOWARRANTY,REPRESENTATIONORGUARANTEEREGARDINGTHESUITABILITYOFITSPRODUCTFORANYPARTICULARPURPOSE,NORDOESSENSIRIONAGASSUMEANYLIABILITYARISINGOUTOFTHEAPPLICATIONORUSEOFANYPRODUCTORCIRCUITANDSPECIFICALLYDISCLAIMSANYANDALLLIABILITY,INCLUDINGWITHOUTLIMITATIONCONSEQUENTIALORINCIDENTALDAMAGES“TYPICAL”PARAMETERSCANANDDOVARYINDIFFERENTAPPLICATIONSALLOPERATINGPARAMETERS,INCLUDING“TYPICAL”MUSTBEVALIDATEDFOREACHCUSTOMERAPPLICATIONSBYCUSTOMERSTECHNICALEXPERTSSENSIRIONAGRESERVESTHERIGHT,WITHOUTFURTHERNOTICE,TOCHANGETHEPRODUCTSPECIFICATIONSAND/ORINFORMATIONINTHISDOCUMENTANDTOIMPROVERELIABILITY,FUNCTIONSANDDESIGN数字温湿度传感器SHT1X/SHT7X_相对湿度和温度测量_兼有露点_全标定输出，无需标定即可互换使用_卓越的长期稳定性_两线制数字接口，无需额外部件_基于请求式测量，因此低能耗_表面贴片或4针引脚安装_超小尺寸_自动休眠SHT1X/SHT7X产品概述SHTXX系列产品是一款高度集成的温湿度传感器芯片，提供全标定的数字输出。它采用专利的CMOSENS技术，确保产品具有极高的可靠性与卓越的长期稳定性。传感器包括一个电容性聚合体测湿敏感元件、一个用能隙材料制成的测温元件，并在同一芯片上，与14位的A/D转换器以及串行接口电路实现无缝连接。因此，该产品具有品质卓越、超快响应、抗干扰能力强、极高的性价比等优点。每个传感器芯片都在极为精确的湿度腔室中进行标定，以镜面冷凝式湿度计为参照。校准系数以程序形式储存在OTP内存中，在标定的过程中使用。两线制的串行接口与内部的电压调整，使外围系统集成变得快速而简单。微小的体积、极低的功耗，使其成为各类应用的首选。产品提供表面贴片LCC或4针单排引脚封装。特殊封装形式可根据用户需求而提供。应用领域框图_暖通空调HVAC_汽车_消费品_气象站_湿度调节器_除湿器_测试及检测设备_数据记录器_自动控制_家电_医疗2接口说明图2典型应用电路21电源引脚SHTXX的供电电压为2455V。传感器上电后，要等待11MS以越过“休眠”状态。在此期间无需发送任何指令。电源引脚（VDD，GND）之间可增加一个100NF的电容，用以去耦滤波。22串行接口两线双向SHTXX的串行接口，在传感器信号的读取及电源损耗方面，都做了优化处理；但与I2C接口不兼容，详情参见FAQ221串行时钟输入SCKSCK用于微处理器与SHTXX之间的通讯同步。由于接口包含了完全静态逻辑，因而不存在最小SCK频率。222串行数据DATADATA三态门用于数据的读取。DATA在SCK时钟下降沿之后改变状态，并仅在SCK时钟上升沿有效。数据传输期间，在SCK时钟高电平时，DATA必须保持稳定。为避免信号冲突，微处理器应驱动DATA在低电平。需要一个外部的上拉电阻（例如10K）将信号提拉至高电平（参见图2）。上拉电阻通常已包含在微处理器的I/O电路中。详细的IO特性，参见表5。223发送命令用一组“启动传输”时序，来表示数据传输的初始化。它包括当SCK时钟高电平时DATA翻转为低电平，紧接着SCK变为低电平，随后是在SCK时钟高电平时DATA翻转为高电平。图3“启动传输“时序后续命令包含三个地址位（目前只支持“000”），和五个命令位。SHTXX会以下述方式表示已正确地接收到指令在第8个SCK时钟的下降沿之后，将DATA下拉为低电平（ACK位）。在第9个SCK时钟的下降沿之后，释放DATA（恢复高电平）。表2SHT控制命令代码命令代码含义00011测量温度00101测量湿度00111读内部状态寄存器11110复位命令，使内部状态寄存器恢复默认值，下一次命令前至少等11MS其他保留224测量时序RH和T发布一组测量命令（00000101表示相对湿度RH，00000011表示温度T）后，控制器要等待测量结束。这个过程需要大约11/55/210MS，分别对应8/12/14BIT测量。确切的时间随内部晶振速度，最多有15变化。SHTXX通过下拉DATA至低电平并进入空闲模式，表示测量的结束。控制器在再次触发SCK时钟前，必须等待这个“数据备妥”信号来读出数据。检测数据可以先被存储这样控制器可以继续执行其它任务在需要时再读出数据。接着传输2个字节的测量数据和1个字节的CRC奇偶校验。UC需要通过下拉DATA为低电平，以确认每个字节。所有的数据从MSB开始，右值有效（例如对于12BIT数据，从第5个SCK时钟起算作MSB；而对于8BIT数据，首字节则无意义）。用CRC数据的确认位，表明通讯结束。如果不使用CRC8校验，控制器可以在测量值LSB后，通过保持确认位ACK高电平，来中止通讯。在测量和通讯结束后，SHTXX自动转入休眠模式。警告为保证自身温升低于01，SHTXX的激活时间不要超过15（例如，对应12BIT精度测量，每秒最多进行3次测量）。225通讯复位时序如果与SHTXX通讯中断，下列信号时序可以复位串口当DATA保持高电平时，触发SCK时钟9次或更多。在下一次指令前，发送一个“传输启动”时序。这些时序只复位串口，状态寄存器内容仍然保留。图4通讯复位时序226CRC8校验数字信号的整个传输过程由8BIT校验来确保。任何错误数据将被检测到并清除。详情可参阅应用说明“CRC8校验”。图6测量时序概览TS启动传输23状态寄存器SHTXX的某些高级功能可以通过状态寄存器实现。下面的章节概括介绍了这些功能。详情可参阅应用说明“状态寄存器”。图7状态寄存器读图8状态寄存器写231测量分辨率默认的测量分辨率分别为14BIT（温度）、12BIT（湿度），也可分别降至12BIT和8BIT。通常在高速或超低功耗的应用中采用该功能。232电量不足“电量不足”功能可监测到VDD电压低于247V的状态。精度为005V。233加热元件芯片上集成了一个可通断的加热元件。接通后，可将SHTXX的温度提高大约5（9）。功耗增加8MA5V。应用于比较加热前后的温度和湿度值，可以综合验证两个传感器元件的性能。在高湿95RH环境中，加热传感器可预防结露，同时缩短响应时间，提高精度。警告加热SHTXX后温度升高、相对湿度降低，较之加热前，示值略有差异。3输出转换为物理量31相对湿度为了补偿湿度传感器的非线性以获取准确数据，建议使用如下公式1修正读数RHLINEARC1C2SORHC32表6湿度转换系数表7温度补偿系数湿度传感器对电压基本上没有依赖性。图10从SORH转换到相对湿度311相对湿度对于温度依赖性的补偿由于实际温度与测试参考温度2577的显著不同，应考虑湿度传感器的温度修正系数RHTRUETC25T1T2SORHRHLINEAR32温度由能隙材料PTAT正比于绝对温度研发的温度传感器具有极好的线性。可用如下公式将数字输出转换为温度值TEMPERATURED1D2SOT表8温度转换系数33露点由于湿度与温度经由同一块芯片测量，SHTXX系列产品可以同时实现高质量的露点测量。可参阅应用说明“露点计算”。4应用信息41工作与贮存条件图11建议的工作条件超出建议的工作范围可能导致最大3的RH信号暂时性漂移。当恢复到正常工作条件后，传感器会缓慢自恢复到校正状态。可参阅43小节的“恢复处理”以加