产品eset

TMP451ZHCSB68A–JUNE2013–REVISEDDECEMBER2014TMP451具具有有η因因子子和和偏偏移移校校正正、、串串联联电电阻阻抵抵消消和和可可编编程程数数字字滤滤波波器器功功能能的的±1°C远远程程和和本本地地温温度度传传感感器器1特特性性3说说明明1本地和远程二极管传感器精度为±1°CTMP451器件是一款高精度低功耗远程温度传感器监控器,内置有一个本地温度传感器.
这类远程温度传本地和远程通道的分辨率为0.
0625°C感器通常采用低成本离散式NPN或PNP晶体管,或1.
7V至3.
6V电源和逻辑电压范围者基板热晶体管或二极管,这些器件都是微处理器、微27A运行电流,3A关断电流控制器或FPGA的组成部件.
本地和远程传感器均用串联电阻抵消12位数字编码表示温度,分辨率为0.
0625°C.
对于η因子和偏移校正本地和远程温度传感器,在典型运行范围内,温度精度可编程数字滤波器为±1°C(最大值).
此两线制串口接受SMBus通信二极管故障检测协议.
两线制和SMBus串行接口8引线超薄小外形尺寸(WSON)(超薄四方扁平诸如串联电阻抵消、可编程非线性因子(η因子)、可(WQFN))封装编程偏移、可编程温度限制和一个可编程数字滤波器等的高级特性被组合在一起以提供一个具有更佳准确度和2应应用用抗扰度的稳健耐用热度监控解决方案.
处理器和现场可编程栅极阵列(FPGA)温度监视TMP451器件适用于多个位置和多种汽车子系统中的智能手机和平板电脑高精度温度测量.
此器件的额定运行电源电压范围为服务器、台式机和笔记本电脑1.
7V至3.
6V,额定工作温度范围为-40°C至125°C.
电信设备以及存储局域网(SAN)器器件件信信息息(1)器器件件型型号号封封装装封封装装尺尺寸寸((标标称称值值))TMP451WSON(8)2.
00mmx2.
00mm(1)要了解所有可用封装,请见数据表末尾的可订购产品附录.
简简化化电电路路原原理理图图1PRODUCTIONDATAinformationiscurrentasofpublicationdate.
ProductsconformtospecificationsperthetermsoftheTexasInstrumentsstandardwarranty.
Productionprocessingdoesnotnecessarilyincludetestingofallparameters.
EnglishDataSheet:SBOS686TMP451ZHCSB68A–JUNE2013–REVISEDDECEMBER2014www.
ti.
com.
cn目目录录7.
3FeatureDescription.
81特特性性.
17.
4DeviceFunctionalModes.
122应应用用.
17.
5Programming.
123说说明明.
17.
6RegisterMap.
164修修订订历历史史记记录录28ApplicationandImplementation295PinConfigurationandFunctions.
38.
1ApplicationInformation.
296Specifications.
38.
2TypicalApplication296.
1AbsoluteMaximumRatings39PowerSupplyRecommendations.
326.
2ESDRatings.
310Layout.
326.
3RecommendedOperatingConditions.
410.
1LayoutGuidelines326.
4ThermalInformation.
410.
2LayoutExample336.
5ElectricalCharacteristics.
411器器件件和和文文档档支支持持346.
6TimingRequirements511.
1商标.
346.
7TypicalCharacteristics.
611.
2静电放电警告.
347DetailedDescription811.
3术语表347.
1Overview812机机械械封封装装和和可可订订购购信信息息347.
2FunctionalBlockDiagram84修修订订历历史史记记录录ChangesfromOriginal(June2013)toRevisionAPageAddedESDRatingstable,FeatureDescriptionsection,DeviceFunctionalModes,ApplicationandImplementationsection,PowerSupplyRecommendationssection,Layoutsection,DeviceandDocumentationSupportsection,andMechanical,Packaging,andOrderableInformationsection32Copyright2013–2014,TexasInstrumentsIncorporatedTMP451www.
ti.
com.
cnZHCSB68A–JUNE2013–REVISEDDECEMBER20145PinConfigurationandFunctionsDQFPackage8-PinWSONTopViewPinFunctionsPINTYPEDESCRIPTIONNAMENO.
InterruptorSMBusalertoutput.
CanbeconfiguredasasecondTHERMoutput.
Open-drain;requiresALERT/THERM26Digitaloutputpullupresistortovoltagebetween1.
7Vand3.
6V.
D–3AnaloginputNegativeconnectiontoremotetemperaturesensor.
D+2AnaloginputPositiveconnectiontoremotetemperaturesensor.
GND5GroundSupplygroundconnection.
SerialclocklineforSMBus.
Input;requirespullupresistortovoltagebetween1.
7Vand3.
6VifdrivenSCL8Digitalinputbyopen-drainoutput.
BidirectionaldigitalSDA7SerialdatalineforSMBus.
Open-drain;requirespullupresistortovoltagebetween1.
7Vand3.
6V.
input-outputThermalshutdownorfan-controlpin.
Open-drain;requirespullupresistortovoltagebetween1.
7VandTHERM4Digitaloutput3.
6V.
V+1PowersupplyPositivesupplyvoltage,1.
7Vto3.
6V.
6Specifications6.
1AbsoluteMaximumRatingsOveroperatingfree-airtemperaturerange,unlessotherwisenoted.
(1)MINMAXUNITPowersupplyV+–0.
33.
6VTHERM,ALERT/THERM2,SDAandSCLonly–0.
33.
6VInputvoltageD+only–0.
3(V+)+0.
3VD–only–0.
30.
3VInputcurrent10mAOperatingtemperature–55127°CJunctiontemperature(TJmax)150°CTstgStoragetemperature–60150°C(1)Stressesabovetheseratingsmaycausepermanentdamage.
Exposuretoabsolutemaximumconditionsforextendedperiodsmaydegradedevicereliability.
Thesearestressratingsonly,andfunctionaloperationofthedeviceattheseoranyotherconditionsbeyondthosespecifiedisnotimplied.
6.
2ESDRatingsVALUEUNITHumanbodymodel(HBM),perANSI/ESDA/JEDECJS-001,allpins(1)±2000V(ESD)ElectrostaticdischargeVChargeddevicemodel(CDM),perJEDECspecificationJESD22-C101,all±750pins(2)(1)JEDECdocumentJEP155statesthat500-VHBMallowssafemanufacturingwithastandardESDcontrolprocess.
(2)JEDECdocumentJEP157statesthat250-VCDMallowssafemanufacturingwithastandardESDcontrolprocess.
Copyright2013–2014,TexasInstrumentsIncorporated3TMP451ZHCSB68A–JUNE2013–REVISEDDECEMBER2014www.
ti.
com.
cn6.
3RecommendedOperatingConditionsoveroperatingfree-airtemperaturerange(unlessotherwisenoted)MINNOMMAXUNITSupplyvoltage1.
73.
33.
6VTAOperatingfree-airtemperature–40125°C6.
4ThermalInformationTMP451THERMALMETRIC(1)DQFUNIT8PINSRθJAJunction-to-ambientthermalresistance171.
3RθJC(top)Junction-to-case(top)thermalresistance81.
4RθJBJunction-to-boardthermalresistance137.
9°C/WψJTJunction-to-topcharacterizationparameter3.
9ψJBJunction-to-boardcharacterizationparameter140(1)Formoreinformationabouttraditionalandnewthermalmetrics,seetheICPackageThermalMetricsapplicationreport,SPRA953.
6.
5ElectricalCharacteristicsAtTA=–40°Cto125°CandV+=3.
3V,unlessotherwisenoted.
PARAMETERCONDITIONSMINTYPMAXUNITTEMPERATUREERRORTA=0°Cto70°C±0.
25±1°CTELOCALLocaltemperaturesensorTA=–40°Cto125°C±1±2°CTA=0°Cto70°C,TD=–55°Cto150°C±0.
25±1°CTEREMOTERemotetemperaturesensor(1)TA=–40°Cto100°C,TD=–55°Cto150°C±1±2°CTA=–40°Cto125°C,TD=–55°Cto150°C±2±4°CRemotetemperaturesensorversussupplyV+=1.
7Vto3.
6V±0.
1±0.
25°C/V(localorremote)TEMPERATUREMEASUREMENTConversiontimeOne-Shotmode,localandremotetotal3134msLocaltemperaturesensorresolution12BitsRemotetemperaturesensorresolution12BitsRemotesensorsourcecurrent,highSeriesresistance1kmax120μARemotesensorsourcecurrent,medium45μARemotesensorsourcecurrent,low7.
5μAηRemotetransistoridealityfactorTMP451optimizedidealityfactor1.
008SMBusINTERFACEVIHHigh-levelinputvoltage1.
4VVILLow-levelinputvoltage0.
45VHysteresis200mVSMBusoutputlowsinkcurrent6mAVOLLow-leveloutputvoltageIO=6mA0.
150.
4VLogicinputcurrent0V≤VI≤3.
6V–11μASMBusinputcapacitance3pFSMBusclockfrequency0.
012.
5MHzSMBustime-out202530msSCLfallingedgetoSDAvalidtime1μsDIGITALOUTPUTS(THERM,ALERT/THERM2)VOLLow-leveloutputvoltageIO=6mA0.
150.
4VIOHHigh-leveloutputleakagecurrentVO=V+1μA(1)Testedwithlessthan5-effectiveseriesresistanceand100-pFdifferentialinputcapacitance.
4Copyright2013–2014,TexasInstrumentsIncorporatedTMP451www.
ti.
com.
cnZHCSB68A–JUNE2013–REVISEDDECEMBER2014ElectricalCharacteristics(continued)AtTA=–40°Cto125°CandV+=3.
3V,unlessotherwisenoted.
PARAMETERCONDITIONSMINTYPMAXUNITPOWERSUPPLYV(V+)Specifiedvoltagerange1.
73.
6V0.
0625conversionspersecond2740μA16conversionspersecond165250μA32conversionspersecond300450μAIQQuiescentcurrentSerialbusinactive,shutdownmode38μASerialbusactive,S=400kHz,shutdownmode90μASerialbusactive,S=2.
5MHz,shutdownmode350μAPORPower-onresetthreshold1.
21.
55V6.
6TimingRequirementsFASTMODEHIGH-SPEEDMODEPARAMETERMINTYPMAXMINTYPMAXUNIT(SCL)SCLoperatingfrequency0.
0010.
40.
0012.
5MHzt(BUF)BusfreetimebetweenSTOPandSTARTCondition1300260nsHoldtimeafterrepeatedSTARTcondition.
Afterthist(HDSTA)600160nsperiod,thefirstclockisgenerated.
t(SUSTA)RepeatedSTARTconditionsetuptime600160nst(SUSTO)STOPconditionsetuptime600160nst(HDDAT)Dataholdtime09000150nst(SUDAT)Datasetuptime10030nst(LOW)SCLclockLOWperiod1300260nst(HIGH)SCLclockHIGHperiod60060nstF,tR–Datafallandrisetime30080nsSDAtF,tR–Clockfallandrisetime30040nsSCLtRRisetimeforSCL≤100kHz1000nsFigure1.
Two-WireTimingDiagramCopyright2013–2014,TexasInstrumentsIncorporated5TMP451ZHCSB68A–JUNE2013–REVISEDDECEMBER2014www.
ti.
com.
cn6.
7TypicalCharacteristicsAtTA=25°CandV+=3.
3V,unlessotherwisenoted.
Figure2.
LocalTemperatureErrorvsTemperatureFigure3.
RemoteTemperatureErrorvsTemperatureFigure4.
RemoteTemperatureErrorvsLeakageResistanceFigure5.
RemoteTemperatureErrorvsSeriesResistanceFigure6.
RemoteTemperatureErrorvsdifferentialFigure7.
RemoteTemperatureErrorvsRemoteChannelCapacitanceNoiseFrequency6Copyright2013–2014,TexasInstrumentsIncorporatedTMP451www.
ti.
com.
cnZHCSB68A–JUNE2013–REVISEDDECEMBER2014TypicalCharacteristics(continued)AtTA=25°CandV+=3.
3V,unlessotherwisenoted.
Figure8.
QuiescentCurrentvsConversionRateFigure9.
ShutdownQuiescentCurrentvsSCLClockFrequencyFigure10.
QuiescentCurrentvsSupplyVoltageFigure11.
ShutdownQuiescentCurrent(AtDefaultConversionRateof16ConversionsperSecond)vsSupplyVoltageCopyright2013–2014,TexasInstrumentsIncorporated7TMP451ZHCSB68A–JUNE2013–REVISEDDECEMBER2014www.
ti.
com.
cn7DetailedDescription7.
1OverviewTheTMP451deviceisadigitaltemperaturesensorthatcombinesalocaltemperaturemeasurementchannelandaremote-junctiontemperaturemeasurementchannelinasingleDFN-8package.
Thedeviceistwo-wire-andSMBus-interfacecompatible,andisspecifiedoveratemperaturerangeof–40°Cto125°C.
TheTMP451devicealsocontainsmultipleregistersforprogrammingandholdingconfigurationsettings,temperaturelimits,andtemperaturemeasurementresults.
7.
2FunctionalBlockDiagram7.
3FeatureDescription7.
3.
1TemperatureMeasurementDataThelocalandremotetemperaturesensorshavearesolutionof12bits(0.
0625°C).
Temperaturedatathatresultfromconversionswithinthedefaultmeasurementrangearerepresentedinbinaryform,asshownintheSTANDARDBINARYcolumnofTable1.
Anytemperaturebelow0°Cresultsinadatavalueof0(00h).
Likewise,temperaturesabove127°Cresultinavalueof127(7Fh).
Thedevicecanbesettomeasureoveranextendedtemperaturerangebychangingbit2(RANGE)ofconfigurationregisterfromlowtohigh.
Thechangeinmeasurementrangeanddataformatfromstandardbinarytoextendedbinaryoccursatthenexttemperatureconversion.
Fordatacapturedintheextendedtemperaturerangeconfiguration,anoffsetof64(40h)isaddedtothestandardbinaryvalue,asshownintheEXTENDEDBINARYcolumnofTable1.
Thisconfigurationallowsmeasurementoftemperaturesaslowas–64°C,andashighas191°C;however,mosttemperature-sensingdiodesonlymeasurewiththerangeof–55°Cto150°C.
Additionally,theTMP451deviceisspecifiedonlyforambienttemperaturesrangingfrom–40°Cto125°C;parametersintheAbsoluteMaximumRatingstablemustbeobserved.
8Copyright2013–2014,TexasInstrumentsIncorporatedTMP451www.
ti.
com.
cnZHCSB68A–JUNE2013–REVISEDDECEMBER2014FeatureDescription(continued)Table1.
TemperatureDataFormat(LocalandRemoteTemperatureHighBytes)LOCALANDREMOTETEMPERATUREREGISTERHIGHBYTEVALUE(1°CRESOLUTION)STANDARDBINARY(1)EXTENDEDBINARY(2)TEMPERATURE(°C)BINARYHEXBINARYHEX–6400000000000000000000–500000000000000011100E–250000000000001001112700000000000010000004010000000101010000014150000010105010001014510000010100A010010104A2500011001190101100159500011001032011100107275010010114B100010118B100011001006410100100A4125011111017D10111101BD127011111117F10111111BF150011111117F11010110D6175011111117F11101111EF191011111117F11111111FF(1)Resolutionis1°C/count.
Negativevaluesproduceareadof0°C.
(2)Resolutionis1°C/count.
Allvaluesareunsignedwitha–64°Coffset.
Bothlocalandremotetemperaturedatausetwobytesfordatastorage.
Thehighbytestoresthetemperaturewith1°Cresolution.
Thesecondorlowbytestoresthedecimalfractionvalueofthetemperatureandallowsahighermeasurementresolution,asshowninTable2.
Themeasurementresolutionforboththelocalandtheremotechannelsis0.
0625°C.
Table2.
DecimalFractionTemperatureDataFormat(LocalandRemoteTemperatureLowBytes)TEMPERATUREREGISTERLOWBYTEVALUE(0.
0625°CRESOLUTION)(1)TEMP(°C)STANDARDANDEXTENDEDBINARYHEX000000000000.
062500010000100.
125000100000200.
187500110000300.
250001000000400.
312501010000500.
375001100000600.
437501110000700.
500010000000800.
562510010000900.
625010100000A00.
687510110000B00.
750011000000C00.
812511010000D00.
875011100000E00.
938511110000F0(1)Resolutionis0.
0625°C/count.
Allpossiblevaluesareshown.
Copyright2013–2014,TexasInstrumentsIncorporated9TMP451ZHCSB68A–JUNE2013–REVISEDDECEMBER2014www.
ti.
com.
cn7.
3.
1.
1StandardBinary-to-DecimalTemperatureDataCalculationExampleHigh-byteconversion(forexample,01110011):Converttheright-justifiedbinaryhighbytetohexadecimal.
Fromhexadecimal,multiplythefirstnumberby160=1andthesecondnumberby161=16.
Thesumequalsthedecimalequivalent.
01110011b→73h→(3*160)+(7*161)=115Low-byteconversion(forexample,01110000):Toconverttheleft-justifiedbinarylow-bytetodecimal,usebits7through4andignorebits3through0becausetheydonotaffectthevalueofthenumber.
0111b→(0*1/2)1+(1*1/2)2+(1*1/2)3+(1*1/2)4=0.
43757.
3.
1.
2StandardDecimal-to-BinaryTemperatureDataCalculationExampleForpositivetemperatures(forexample,20°C):(20°C)/(1°C/count)=20→14h→00010100Convertthenumbertobinarycodewith8-bit,right-justifiedformat,andMSB=0todenoteapositivesign.
20°Cisstoredas00010100→14h.
Fornegativetemperatures(forexample,–20°C):(|–20|)/(1°C/count)=20→14h→00010100Generatethetwo'scomplementofanegativenumberbycomplementingtheabsolutevaluebinarynumberandadding1.
–20°Cisstoredas11101100→ECh.
7.
3.
2SeriesResistanceCancellationSeriesresistancecancellationautomaticallyeliminatesthetemperatureerrorcausedbytheresistanceoftheroutingtotheremotetransistororbytheresistorsoftheoptionalexternallow-passfilter.
Atotalofupto1kΩofseriesresistancecanbecancelledbytheTMP451device,eliminatingtheneedforadditionalcharacterizationandtemperatureoffsetcorrection.
SeeFigure5fordetailsontheeffectsofseriesresistanceonsensedremotetemperatureerror.
7.
3.
3DifferentialInputCapacitanceTheTMP451devicetoleratesdifferentialinputcapacitanceofupto1000pFwithminimalchangeintemperatureerror.
TheeffectofcapacitanceonsensedremotetemperatureerrorisshowninFigure6.
7.
3.
4FilteringRemotejunctiontemperaturesensorsareusuallyimplementedinanoisyenvironment.
Noiseismostoftencreatedbyfastdigitalsignals,anditcancorruptmeasurements.
TheTMP451devicehasabuilt-in,65-kHzfilterontheinputsofD+andD–tominimizetheeffectsofnoise.
However,abypasscapacitorplaceddifferentiallyacrosstheinputsoftheremotetemperaturesensorisrecommendedtomaketheapplicationmorerobustagainstunwantedcoupledsignals.
Forthiscapacitor,selectavalueofbetween100pFand1nF.
Someapplicationsattainbetteroverallaccuracywithadditionalseriesresistance;however,thisincreasedaccuracyisapplication-specific.
Whenseriesresistanceisadded,thetotalvalueshouldnotbegreaterthan1k.
Iffilteringisrequired,suggestedcomponentvaluesare100pFand50oneachinput;exactvaluesareapplication-specific.
10Copyright2013–2014,TexasInstrumentsIncorporatedTMP451www.
ti.
com.
cnZHCSB68A–JUNE2013–REVISEDDECEMBER2014Additionally,adigitalfilterisavailablefortheremotetemperaturemeasurementstofurtherreducetheeffectofnoise.
Thisfilterisprogrammableandhastwolevelswhenenabled.
Level1performsamovingaverageoffourconsecutivesamples.
Level2performsamovingaverageofeightconsecutivesamples.
Thevaluestoredintheremotetemperatureresultregisteristheoutputofthedigitalfilter,andtheALERTandTHERMlimitsarecomparedtoit.
ThisprovidesadditionalimmunitytonoiseandspikesontheALERTandTHERMoutputs.
ThefilterresponsesareshowninFigure12.
Thefiltercanbeenabledordisabledbyprogrammingthedesiredlevelsinthedigitalfilterregister.
ThedigitalfilterisdisabledbydefaultandonPOR.
Figure12.
FilterResponsetoImpulseandStepInputs7.
3.
5SensorFaultTheTMP451devicecansenseafaultattheD+inputresultingfromincorrectdiodeconnection.
TheTMP451devicecanalsosenseanopencircuit.
Short-circuitconditionsreturnavalueof–64°C.
ThedetectioncircuitryconsistsofavoltagecomparatorthattripswhenthevoltageatD+exceeds(V+)–0.
3V(typical).
Thecomparatoroutputiscontinuouslycheckedduringaconversion.
Ifafaultisdetected,thenOPEN(bit2)inthestatusregisterissetto1.
WhennotusingtheremotesensorwiththeTMP451device,theD+andD–inputsmustbeconnectedtogethertopreventmeaninglessfaultwarnings.
Copyright2013–2014,TexasInstrumentsIncorporated11TMP451ZHCSB68A–JUNE2013–REVISEDDECEMBER2014www.
ti.
com.
cn7.
3.
6ALERTandTHERMFunctionsTheoperationoftheALERT(pin6)andTHERM(pin4)interruptsisshowninFigure13.
TheoperationoftheTHERM(pin4)andTHERM2(pin6)interruptsisshowninFigure14.
Figure13.
ALERTandTHERMInterruptOperationFigure14.
THERMandTHERM2InterruptOperationThehysteresisvalueisstoredintheTHERMhysteresisregister.
ThevalueoftheCONAL[2:0]bitsintheconsecutiveALERTregisterdeterminesthenumberoflimitviolationsbeforetheALERTpinistripped.
Thedefaultvalueis000bandcorrespondstooneviolation,001bprogramstwoconsecutiveviolations,011bprogramsthreeconsecutiveviolations,and111bprogramsfourconsecutiveviolations.
ThisprovidesadditionalfilteringfortheALERTpinstate.
7.
4DeviceFunctionalModes7.
4.
1ShutdownMode(SD)TheTMP451shutdownmodeenablestheusertosavemaximumpowerbyshuttingdownalldevicecircuitryotherthantheserialinterface,reducingcurrentconsumptiontotypicallylessthan3μA;seeFigure11.
ShutdownmodeisenabledwhentheSDbit(bit6)oftheconfigurationregisterishigh;thedeviceshutsdownafterthecurrentconversionisfinished.
WhentheSDbitislow,thedevicemaintainsacontinuous-conversionstate.
7.
4.
2One-shotModeWhentheTMP451deviceisinshutdownmode(SD=1intheconfigurationregister),asingleconversionisstartedbywritinganyvaluetotheone-shotstartregister,pointeraddress0Fh.
Thiswriteoperationstartsoneconversionandcomparisoncycleonboththelocalandtheremotesensors.
TheTMP451devicereturnstoshutdownmodewhenthecyclecompletes.
ThevalueofthedatasentinthewritecommandisirrelevantandisnotstoredbytheTMP451device.
7.
5Programming7.
5.
1SerialInterfaceTheTMP451deviceoperatesonlyasaslavedeviceoneitherthetwo-wirebusortheSMBus.
Connectionstoeitherbusaremadeusingtheopen-drainI/Olines,SDAandSCL.
TheSDAandSCLpinsfeatureintegratedspikesuppressionfiltersandSchmitttriggerstominimizetheeffectsofinputspikesandbusnoise.
TheTMP451devicesupportsthetransmissionprotocolforfast(1kHzto400kHz)andhigh-speed(1kHzto2.
5MHz)modes.
AlldatabytesaretransmittedMSBfirst.
12Copyright2013–2014,TexasInstrumentsIncorporatedTMP451www.
ti.
com.
cnZHCSB68A–JUNE2013–REVISEDDECEMBER2014Programming(continued)7.
5.
1.
1BusOverviewTheTMP451deviceisSMBusinterfacecompatible.
InSMBusprotocol,thedevicethatinitiatesthetransferiscalledamaster,andthedevicescontrolledbythemasterareslaves.
Thebusmustbecontrolledbyamasterdevicethatgeneratestheserialclock(SCL),controlsthebusaccess,andgeneratestheSTARTandSTOPconditions.
Toaddressaspecificdevice,aSTARTconditionisinitiated.
ASTARTconditionisindicatedbypullingthedataline(SDA)fromahigh-to-lowlogiclevelwhileSCLishigh.
Allslavesonthebusshiftintheslaveaddressbyte,withthelastbitindicatingwhetherareadorwriteoperationisintended.
Duringtheninthclockpulse,theslavebeingaddressedrespondstothemasterbygeneratinganacknowledgebitandpullingSDAlow.
Datatransferistheninitiatedandsentovereightclockpulsesfollowedbyanacknowledgebit.
DuringdatatransferSDAmustremainstablewhileSCLishigh,becauseanychangeinSDAwhileSCLishighisinterpretedasacontrolsignal.
Afteralldatahavebeentransferred,themastergeneratesaSTOPcondition.
ASTOPconditionisindicatedbypullingSDAfromlowtohigh,whileSCLishigh.
7.
5.
1.
2BusDefinitionsTheTMP451deviceistwo-wireandSMBus-compatible.
Figure15andFigure16showthetimingforvariousoperationsontheTMP451device.
Thebusdefinitionsareasfollows:Acknowledge:Eachreceivingdevice,whenaddressed,isobligedtogenerateanacknowledgebit.
AdevicethatacknowledgesmustpulldowntheSDAlineduringtheacknowledgeclockpulseinsuchawaythattheSDAlineisstablelowduringthehighperiodoftheacknowledgeclockpulse.
Takesetupandholdtimesintoaccount.
Onamasterreceive,datatransferterminationcanbesignaledbythemastergeneratinganot-acknowledgeonthelastbytethathasbeentransmittedbytheslave.
BusIdle:BothSDAandSCLlinesremainhigh.
DataTransfer:ThenumberofdatabytestransferredbetweenaSTARTandaSTOPconditionisnotlimitedandisdeterminedbythemasterdevice.
Thereceiveracknowledgesdatatransfer.
StartDataTransfer:AchangeinthestateoftheSDAline,fromhightolow,whiletheSCLlineishigh,definesastartcondition.
EachdatatransferinitiateswithaSTARTcondition.
StopDataTransfer:AchangeinthestateoftheSDAlinefromlowtohighwhiletheSCLlineishighdefinesaSTOPcondition.
EachdatatransferterminateswitharepeatedSTARTorSTOPcondition.
(1)Slaveaddress1001100shown.
Figure15.
Two-WireTimingDiagramforWriteWordFormatCopyright2013–2014,TexasInstrumentsIncorporated13TMP451ZHCSB68A–JUNE2013–REVISEDDECEMBER2014www.
ti.
com.
cnProgramming(continued)(1)Slaveaddress1001100shown.
(2)MastershouldleaveSDAhightoterminateasingle-bytereadoperation.
Figure16.
Two-WireTimingDiagramforSingle-ByteReadFormat7.
5.
1.
3SerialBusAddressTocommunicatewiththeTMP451device,themastermustfirstaddressslavedevicesusingaslaveaddressbyte.
Theslaveaddressbyteconsistsofsevenaddressbits,andadirectionbitindicatingtheintentofexecutingareadorwriteoperation.
TheTMP451devicehasadeviceaddressof4Ch(1001100b).
Additionalfactory-programmeddeviceaddressesareavailableuponrequest.
7.
5.
1.
4ReadandWriteOperationsAccessingaparticularregisterontheTMP451deviceisaccomplishedbywritingtheappropriatevaluetothepointerregister.
ThevalueforthepointerregisteristhefirstbytetransferredaftertheslaveaddressbytewiththeR/Wbitlow.
EverywriteoperationtotheTMP451devicerequiresavalueforthepointerregister(seeFigure15).
WhenreadingfromtheTMP451devicethelastvaluestoredinthepointerregisterbyawriteoperationisusedtodeterminewhichregisterisreadbyareadoperation.
Tochangewhichregisterisreadforareadoperation,anewvaluemustbewrittentothepointerregister.
ThistransactionisaccomplishedbyissuingaslaveaddressbytewiththeR/Wbitlow,followedbythepointerregisterbyte;noadditionaldataarerequired.
ThemastercanthengenerateaSTARTconditionandsendtheslaveaddressbytewiththeR/Wbithightoinitiatethereadcommand;seeFigure16fordetailsofthissequence.
Ifrepeatedreadsfromthesameregisteraredesired,itisnotnecessarytocontinuallysendthepointerregisterbytes,becausetheTMP451deviceretainsthepointerregistervalueuntilitischangedbythenextwriteoperation.
TheregisterbytesaresentMSBfirst,followedbytheLSB.
Readoperationsshouldbeterminatedbyissuinganot-acknowledgecommandattheendofthelastbytetoberead.
Forsingle-byteoperation,themastermustleavetheSDAlinehighduringtheacknowledgetimeofthefirstbytethatisreadfromtheslave.
14Copyright2013–2014,TexasInstrumentsIncorporatedTMP451www.
ti.
com.
cnZHCSB68A–JUNE2013–REVISEDDECEMBER2014Programming(continued)7.
5.
1.
5Time-outFunctionIftheSMBustime-outfunctionisenabled,theTMP451deviceresetstheserialinterfaceifeitherSCLorSDAareheldlowfor25ms(typical)betweenaSTARTandSTOPcondition.
IftheTMP451deviceisholdingthebuslow,thedevicereleasesthebusandwaitsforaSTARTcondition.
Toavoidactivatingthetime-outfunction,maintainingacommunicationspeedofatleast1kHzfortheSCLoperatingfrequencyisnecessary.
TheSMBTObit(bit7)oftheconsecutiveALERTregistercontrolsthetime-outenable.
SettingtheSMBTObittoavalueof0(default)disablesthetime-out.
SettingtheSMBTObittoavalueof1enablesthefunction.
7.
5.
1.
6High-speedModeForthetwo-wirebustooperateatfrequenciesabove1MHz,themasterdevicemustissueahigh-speedmode(Hs-mode)mastercode(00001xxx)asthefirstbyteafteraSTARTconditiontoswitchthebustohigh-speedoperation.
TheTMP451devicedoesnotacknowledgethisbyte,butswitchestheinputfiltersonSDAandSCLandtheoutputfilteronSDAtooperateinHs-mode,allowingtransfersatupto2.
5MHz.
AftertheHs-modemastercodehasbeenissued,themastertransmitsatwo-wireslaveaddresstoinitiateadatatransferoperation.
ThebuscontinuestooperateinHs-modeuntilaSTOPconditionoccursonthebus.
UponreceivingtheSTOPcondition,theTMP451deviceswitchestheinputandoutputfiltersbacktofastmodeoperation.
7.
5.
1.
7GeneralCallResetTheTMP451devicesupportsresetusingthetwo-wiregeneralcalladdress00h(00000000b).
TheTMP451deviceacknowledgesthegeneralcalladdressandrespondstothesecondbyte.
Ifthesecondbyteis06h(00000110b),theTMP451deviceexecutesasoftwarereset.
Thissoftwareresetrestoresthepower-onresetstatetoallTMP451registers,anditabortsanyconversioninprogress.
TheTMP451devicetakesnoactioninresponsetoothervaluesinthesecondbyte.
Copyright2013–2014,TexasInstrumentsIncorporated15TMP451ZHCSB68A–JUNE2013–REVISEDDECEMBER2014www.
ti.
com.
cn7.
6RegisterMapTable3.
RegisterMapBITDESCRIPTIONPOINTERREADPOINTER(HEX)WRITE(HEX)POR(HEX)76543210REGISTERDESCRIPTION00N/A00LT11LT10LT9LT8LT7LT6LT5LT4Localtemperature(highbyte)01N/A00RT11RT10RT9RT8RT7RT6RT5RT4Remotetemperature(highbyte)02N/AN/ABUSYLHIGHLLOWRHIGHRLOWOPENRTHRMLTHRMStatusregisterALERT/030900MASK1SD00RANGE00ConfigurationregisterTHERM2040A080000CR3CR2CR1CR0Conversionrateregister050B55LTHL11LTHL10LTHL9LTHL8LTHL7LTHL6LTHL5LTHL4Localtemperaturehighlimit060C00LTLL11LTLL10LTLL9LTLL8LTLL7LTLL6LTLL5LTLL4Localtemperaturelowlimit070D55RTHL11RTHL10RTHL9RTHL8RTHL7RTHL6RTHL5RTHL4Remotetemperaturehighlimit(highbyte)080E00RTLL11RTLL10RTLL9RTLL8RTLL7RTLL6RTLL5RTLL4Remotetemperaturelowlimit(highbyte)N/A0FN/AXXXXXXXXOne-shotstartTable1410N/A00RT3RT2RT1RT00000Remotetemperature(lowbyte)111100RTOS11RTOS10RTOS9RTOS8RTOS7RTOS6RTOS5RTOS4Remotetemperatureoffset(highbyte)121200RTOS3RTOS2RTOS1RTOS00000Remotetemperatureoffset(lowbyte)131300RTHL3RTHL2RTHL1RTHL00000Remotetemperaturehighlimit(lowbyte)141400RTLL3RTLL2RTLL1RTLL00000Remotetemperaturelowlimit(lowbyte)15N/A00LT3LT2LT1LT00000Localtemperature(lowbyte)19196CRTH11RTH10RTH9RTH8RTH7RTH6RTH5RTH4RemotetemperatureTHERMlimit202055LTH11LTH10LTH9LTH8LTH7LTH6LTH5LTH4LocaltemperatureTHERMlimit21210AHYS11HYS10HYS9HYS8HYS7HYS6HYS5HYS4THERMhysteresis222201SMBTO000CONAL2CONAL1CONAL01ConsecutiveALERT232300NC7NC6NC5NC4NC3NC2NC1NC0η-factorcorrection242400000000DF1DF0DigitalfiltercontrolFEN/A5501010101ManufacturerID16Copyright2013–2014,TexasInstrumentsIncorporatedTMP451www.
ti.
com.
cnZHCSB68A–JUNE2013–REVISEDDECEMBER20147.
6.
1RegisterInformationTheTMP451devicecontainsmultipleregistersforholdingconfigurationinformation,temperaturemeasurementresults,andstatusinformation.
TheseregistersaredescribedinFigure17andTable3.
7.
6.
1.
1PointerRegisterFigure17showstheinternalregisterstructureoftheTMP451device.
The8-bitpointerregisterisusedtoaddressagivendataregister.
Thepointerregisteridentifieswhichofthedataregistersshouldrespondtoareadorwritecommandonthetwo-wirebus.
Thisregisterissetwitheverywritecommand.
Awritecommandmustbeissuedtosetthepropervalueinthepointerregisterbeforeexecutingareadcommand.
Table3describesthepointerregisterandtheinternalstructureoftheTMP451registers.
Thepower-onreset(POR)valueofthepointerregisteris00h(00000000b).
Figure17.
InternalRegisterStructure7.
6.
1.
2TemperatureRegistersTheTMP451devicehasmultiple8-bitregistersthatholdtemperaturemeasurementresults.
Theeightmostsignificantbits(MSBs)ofthelocaltemperaturesensorresultarestoredinregister00h,whilethefourleastsignificantbits(LSBs)arestoredinregister15h(thefourMSBsofregister15h).
TheeightMSBsoftheremotetemperaturesensorresultarestoredinregister01h,andthefourLSBsarestoredinregister10h(thefourMSBsofregister10h).
ThefourLSBsofboththelocalsensorandtheremotesensorindicatethetemperaturevalueafterthedecimalpoint(forexample,ifthetemperatureresultis10.
0625C,thehighbyteis00001010andthelowbyteis00010000).
Theseregistersareread-onlyandareupdatedbytheADCeachtimeatemperaturemeasurement.
Whenthefulltemperaturevalueisneeded,readingtheMSBvaluefirstcausestheLSBvaluetobelocked(theADCdoesnotwritetoit)untilitisread.
ThesamethinghappensuponreadingtheLSBvaluefirst(theMSBvalueislockeduntilitisread).
ThismechanismassuresthatbothbytesofthereadoperationarefromthesameADCconversion.
Thisassuranceremainsvalidonlyuntilanotherregisterisread.
Forproperoperation,readthehighbyteofthetemperatureresultfirst.
Readthelowbyteregisterinthenextreadcommand;iftheLSBsarenotneeded,theregistermaybeleftunread.
Thepower-onresetvalueofalltemperatureregistersis00h.
Copyright2013–2014,TexasInstrumentsIncorporated17TMP451ZHCSB68A–JUNE2013–REVISEDDECEMBER2014www.
ti.
com.
cn7.
6.
1.
3LocalTemperatureHighByteRegister(offset:Read=00h;Write=N/A)[reset=00h]Figure18.
LocalTemperatureHighByteRegister76543210LT11LT10LT9LT8LT7LT6LT5LT4R-0R-0R-0R-0R-0R-0R-0R-0LEGEND:R/W=Read/Write;R=Readonly;-n=valueafterresetTable4.
LocalTemperatureHighByteRegisterFieldDescriptionsBitFieldTypeResetDescription7-0LT11-LT4R0hLocaltemperaturehighbyte.
TheresolutionoftheLSBinthisregisteris1°C.
Thisregisterisread-onlyandisupdatedbytheADCeachtimeatemperaturemeasurementiscompleted.
Whenthefulltemperaturevalueisneeded,readingthehighbyteregisterfirstcausesthelowbyteregistervaluetobelocked(theADCdoesnotwritetoit)untilitisread.
Thesamethinghappensuponreadingthelowbyteregistervaluefirst(thehighbyteregistervalueislockeduntilitisread).
ThismechanismassuresthatbothbytesofthereadoperationarefromthesameADCconversion.
Thisassuranceremainsvalidonlyuntilanotherregisterisread.
Forproperoperation,readthehighbyteofthetemperatureresultfirst.
Readthelowbyteregisterinthenextreadcommand;ifthelowbyteisnotneeded,theregistermaybeleftunread.
7.
6.
1.
4RemoteTemperatureHighByteRegister(offset:Read=01h;Write=N/A)[reset=00h]Figure19.
RemoteTemperatureHighByteRegister76543210RT11RT10RT9RT8RT7RT6RT5RT4R-0hR-0hR-0hR-0hR-0hR-0hR-0hR-0hLEGEND:R/W=Read/Write;R=Readonly;-n=valueafterresetTable5.
RemoteTemperatureHighByteRegisterFieldDescriptionsBitFieldTypeResetDescription7-0RT11-RT4R0hRemotetemperaturehighbyte.
TheresolutionoftheLSBinthisregisteris1°C.
Thisregisterisread-onlyandisupdatedbytheADCeachtimeatemperaturemeasurementiscompleted.
Whenthefulltemperaturevalueisneeded,readingthehighbyteregisterfirstcausesthelowbyteregistervaluetobelocked(theADCdoesnotwritetoit)untilitisread.
Thesamethinghappensuponreadingthelowbyteregistervaluefirst(thehighbyteregistervalueislockeduntilitisread).
ThismechanismassuresthatbothbytesofthereadoperationarefromthesameADCconversion.
Thisassuranceremainsvalidonlyuntilanotherregisterisread.
Forproperoperation,readthehighbyteofthetemperatureresultfirst.
Readthelowbyteregisterinthenextreadcommand;ifthelowbyteisnotneeded,theregistermaybeleftunread.
7.
6.
1.
5StatusRegister(offset:Read=02h;Write=N/A)[reset=N/A]Figure20.
StatusRegister76543210BUSYLHIGHLLOWRHIGHRLOWOPENRTHRMLTHRMRRRRRRRRLEGEND:R/W=Read/Write;R=Readonly;-n=valueafterreset18Copyright2013–2014,TexasInstrumentsIncorporatedTMP451www.
ti.
com.
cnZHCSB68A–JUNE2013–REVISEDDECEMBER2014Table6.
StatusRegisterFieldDescriptionsBitFieldTypeResetDescription7BUSYRN/AADCstatusindicator1=ADCisconverting.
0=ADCisnotconverting.
6LHIGHRN/ALocaltemperaturehighlimitstatusindicator(1)1=LocaltemperaturevalueexceedstheLocalTemperatureHighLimitRegistervalue.
ThisbitiscleareduponreadingtheStatusRegisterprovidingthattheconditioncausingtheovertemperatureresultisnolongerpresent.
0=LocaltemperaturevaluedoesnotexceedtheLocalTemperatureHighLimitRegistervalue.
5LLOWRN/ALocaltemperaturelowlimitstatusindicator(1)1=LocaltemperaturevalueisbelowtheLocalTemperatureLowLimitRegistervalue.
ThisbitiscleareduponreadingtheStatusRegisterprovidingthattheconditioncausingtheundertemperatureresultisnolongerpresent.
0=LocaltemperaturevalueisnotbelowtheLocalTemperatureLowLimitRegistervalue.
4RHIGHRN/ARemotetemperaturehighlimitstatusindicator(1)1=RemotetemperaturevalueexceedstheRemoteTemperatureHighLimitRegistervalue.
ThisbitiscleareduponreadingtheStatusRegisterprovidingthattheconditioncausingtheovertemperatureresultisnolongerpresent.
0=RemotetemperaturevaluedoesnotexceedtheRemoteTemperatureHighLimitRegistervalue.
3RLOWRN/ARemotetemperaturelowlimitstatusindicator(1)1=RemotetemperaturevalueisbelowtheRemoteTemperatureLowLimitRegistervalue.
ThisbitiscleareduponreadingtheStatusRegisterprovidingthattheconditioncausingtheundertemperatureresultisnolongerpresent.
0=RemotetemperaturevalueisnotbelowtheRemoteTemperatureLowLimitRegistervalue.
2OPENRN/ARemotejunctionopencircuitdetection(1)1=Theremotejunctionisanopencircuit.
ThisbitiscleareduponreadingtheStatusRegisterprovidingthattheconditioncausingtheopencircuitisnolongerpresent.
0=Theremotejunctionisnotanopencircuit.
1RTHRMRN/ARemoteTHERMlimitstatusindicator1=RemoteTHERMlimitistripped.
ThisbitiscleareduponreadingtheStatusRegisterprovidingthattheconditioncausingtheovertemperatureresultisnolongerpresent.
0=RemoteTHERMlimitisnottripped.
0LTHRMRN/ALocalTHERMlimitstatusindicator1=LocalTHERMlimitistripped.
ThisbitiscleareduponreadingtheStatusRegisterprovidingthattheconditioncausingtheovertemperatureresultisnolongerpresent.
0=LocalTHERMlimitisnottripped.
(1)TheseflagsstayhighuntilthestatusregisterisreadortheyareresetbyaPORwhenpin6isconfiguredasALERT.
Onlybit2(OPEN)stayshighuntilthestatusregisterisreadoritisresetbyaPORwhenpin6isconfiguredasTHERM2.
ThestatusregisterreportsthestateofthetemperatureADC,thetemperaturelimitcomparators,andtheconnectiontotheremotesensor.
Table6liststhestatusregisterbits.
Thestatusregisterisread-only,andisreadbyaccessingpointeraddress02h.
TheLHIGHandLLOWbitsindicatealocalsensorovertemperatureorundertemperatureevent,respectively.
TheRHIGHandRLOWbitsindicatearemotesensorovertemperatureorundertemperatureevent,respectively.
TheOPENbitindicatesanopen-circuitconditionontheremotesensor.
Whenpin6isconfiguredastheALERToutput,thefiveflagsareNORedtogether.
Ifanyofthefiveflagsarehigh,theALERTinterruptlatchissetandtheALERToutputgoeslow.
Readingthestatusregisterclearsthefiveflags,providedthattheconditionthatCopyright2013–2014,TexasInstrumentsIncorporated19TMP451ZHCSB68A–JUNE2013–REVISEDDECEMBER2014www.
ti.
com.
cncausedthesettingoftheflagsisnotpresentanymore(thatis,thevalueofthecorrespondingresultregisteriswithinthelimits,ortheremotesensorisconnectedproperlyandfunctional).
TheALERTinterruptlatch(andtheALERTpincorrespondingly)isnotresetbyreadingthestatusregister.
Theresetisdonebythemasterreadingthetemperaturesensordeviceaddresstoservicetheinterrupt,andonlyiftheflagshavebeenresetandtheconditionthatcausedthemtobesetisnotpresent.
TheRTHRMandLTHRMflagsaresetwhenthecorrespondingtemperatureexceedstheprogrammedTHERMlimit.
Theyareresetautomaticallywhenthetemperaturereturnstowithinthelimits.
TheTHERMoutputgoeslowinthecaseofovertemperatureoneitherthelocalortheremotechannel,andgoeshighassoonasthemeasurementsarewithinthelimitsagain.
TheTHERMhysteresisregister(21h)allowshysteresistobeaddedsothattheflagresetsandtheoutputgoeshighwhenthetemperaturereturnstoorgoesbelowthelimitvalueminusthehysteresisvalue.
Whenpin6isconfiguredasTHERM2,onlythehighlimitsmatter.
TheLHIGHandRHIGHflagsaresetiftherespectivetemperaturesexceedthelimitvalues,andthepingoeslowtoindicatetheevent.
TheLLOWandRLOWflagshavenoeffectonTHERM2,andtheoutputbehavesthesamewaywhenconfiguredasTHERM.
7.
6.
1.
6ConfigurationRegister(offset:Read=03h;Write=09h)[reset=00h]Figure21.
ConfigurationRegister76543210MASK1SDALERT/THERMRESERVEDRANGERESERVED2R/W-0hR/W-0hR/W-0hR/W-0hR/W-0hR/W-0hLEGEND:R/W=Read/Write;R=Readonly;-n=valueafterresetTable7.
ConfigurationRegisterFieldDescriptionsBitFieldTypeResetDescription7MASK1R/W0hThisbitmaskstheALERToutput1=ALERTisdisabled.
0=ALERTisenabled.
6SDR/W0hDeviceshutdowncontrol1=Placesthedeviceisinshutdownmode.
0=Placesthedeviceincontinuousconversionmode.
5ALERT/THERM2R/W0hALERTorTHERM2modeselect1=THERM2mode0=ALERTmode2RANGER/W0hThisbitconfigurestherangeofthetemperaturemeasurement1=–64°Cto191°C0=0°Cto127°CMASK1oftheconfigurationregistermaskstheALERToutput.
IfMASK1is0(default),theALERToutputisenabled.
IfMASK1issetto1,theALERToutputisdisabled.
ThisconfigurationappliesonlyifthevalueofALERT/THERM2bitis0(thatis,pin6isconfiguredastheALERToutput).
Ifpin6isconfiguredastheTHERM2output,thevalueoftheMASK1bithasnoeffect.
Theshutdownbit,SD,enablesordisablesthetemperature-measurementcircuitry.
IfSD=0(default),theTMP451deviceconvertscontinuouslyattheratesetintheconversionrateregister.
WhenSDissetto1,theTMP451devicestopsconvertingwhenthecurrentconversionsequenceiscompleteandentersashutdownmode.
WhenSDissetto0again,theTMP451resumescontinuousconversions.
WhenSD=1,asingleconversioncanbestartedbywritingtotheone-shotstartregister.
SeetheOne-shotModesectionformoreinformation.
ALERT/THERM2(bit5)setstheconfigurationofpin6.
IftheALERT/THERM2bitis0(default),thenpin6isconfiguredastheALERToutput;ifitissetto1,thenpin6isconfiguredastheTHERM2output.
ThetemperaturerangeissetbyconfiguringRANGE(bit2)oftheconfigurationregister.
Settingthisbitlow(default)configurestheTMP451deviceforthestandardmeasurementrange(0°Cto127°C);temperatureconversionsarestoredinthestandardbinaryformat.
Settingbit2highconfigurestheTMP451devicefortheextendedmeasurementrange(–64°Cto191°C);temperatureconversionsarestoredintheextendedbinaryformat(seeTable1).
20Copyright2013–2014,TexasInstrumentsIncorporatedTMP451www.
ti.
com.
cnZHCSB68A–JUNE2013–REVISEDDECEMBER2014Theremainingbitsoftheconfigurationregisterarereservedandmustalwaysbesetto0.
Thepower-onresetvalueforthisregisteris00h.
7.
6.
1.
7ConversionRateRegister(offset:Read=04h;Write=0Ah)[reset=08h]Figure22.
ConversionRateRegister76543210RESERVEDCR3CR2CR1CR0R/W-0hR/W-1hR/W-0hR/W-0hR/W-0hLEGEND:R/W=Read/Write;R=Readonly;-n=valueafterresetTable8.
ConversionRateRegisterFieldDescriptionsBitFieldTypeResetDescription3-0CR3-CR0R/W8hConversionrateselection.
RefertoTable9Theconversionrateregister(readaddress04h,writeaddress0Ah)controlstherateatwhichtemperatureconversionsareperformed.
Thisregisteradjuststheidletimebetweenconversionsbutnottheconversiontimeitself,therebyallowingtheTMP451powerdissipationtobebalancedwiththetemperatureregisterupdaterate.
Table9liststheconversionrateoptionsandcorrespondingtimebetweenconversions.
Thedefaultvalueoftheregisteris08h,whichgivesadefaultrateof16conversionspersecond.
Table9.
ConversionRateVALUECONVERSIONSPERSECONDTIME(SECONDS)00h0.
06251601h0.
125802h0.
25403h0.
5204h1105h20.
506h40.
2507h80.
12508h16(default)0.
0625(default)09h320.
031257.
6.
1.
8LocalTemperatureHighLimitRegister(offset:Read=05h;Write=0Bh)[reset=55h]Figure23.
LocalTemperatureHighLimitRegister76543210LTHL11LTHL10LTHL9LTHL8LTHL7LTHL6LTHL5LTHL4R/W-0hR/W-1hR/W-0hR/W-1hR/W-0hR/W-1hR/W-0hR/W-1hLEGEND:R/W=Read/Write;R=Readonly;-n=valueafterresetTable10.
LocalTemperatureHighLimitRegisterFieldDescriptionsBitFieldTypeResetDescription7-0LTHL11-LTHL4R/W55hThesebitsdeterminethevalueofthehightemperaturelimittowhichthelocaltemperaturemeasurementiscompared.
TheresolutionoftheLSBinthisregisteris1°C.
Copyright2013–2014,TexasInstrumentsIncorporated21TMP451ZHCSB68A–JUNE2013–REVISEDDECEMBER2014www.
ti.
com.
cn7.
6.
1.
9LocalTemperatureLowLimitRegister(offset:Read=06h;Write=0Ch)[reset=00h]Figure24.
LocalTemperatureLowLimitRegister76543210LTLL11LTLL10LTLL9LTLL8LTLL7LTLL6LTLL5LTLL4R/W-0hR/W-0hR/W-0hR/W-0hR/W-0hR/W-0hR/W-0hR/W-0hLEGEND:R/W=Read/Write;R=Readonly;-n=valueafterresetTable11.
LocalTemperatureLowLimitRegisterFieldDescriptionsBitFieldTypeResetDescription7-0LTLL11-LTLL4R/W00hThesebitsdeterminethevalueofthelowtemperaturelimittowhichthelocaltemperaturemeasurementiscompared.
TheresolutionoftheLSBinthisregisteris1°C.
7.
6.
1.
10RemoteTemperatureHighLimitHighByteRegister(offset:Read=07h;Write=0Dh)[reset=55h]Figure25.
RemoteTemperatureHighLimitHighByteRegister76543210RTHL11RTHL10RTHL9RTHL8RTHL7RTHL6RTHL5RTHL4R/W-0hR/W-1hR/W-0hR/W-1hR/W-0hR/W-1hR/W-0hR/W-1hLEGEND:R/W=Read/Write;R=Readonly;-n=valueafterresetTable12.
RemoteTemperatureHighLimitHighByteRegisterFieldDescriptionsBitFieldTypeResetDescription7-0RTHL11-RTHL4R/W55hThesebitsdeterminethevalueofthehighbyteofthehightemperaturelimittowhichtheremotetemperaturemeasurementiscompared.
TheresolutionoftheLSBinthisregisteris1°C.
7.
6.
1.
11RemoteTemperatureLowLimitHighByteRegister(offset:Read=08h;Write=0Eh)[reset=00h]Figure26.
RemoteTemperatureLowLimitHighByteRegister76543210RTLL11RTLL10RTLL9RTLL8RTLL7RTLL6RTLL5RTLL4R/W-0hR/W-0hR/W-0hR/W-0hR/W-0hR/W-0hR/W-0hR/W-0hLEGEND:R/W=Read/Write;R=Readonly;-n=valueafterresetTable13.
RemoteTemperatureLowLimitHighByteRegisterFieldDescriptionsBitFieldTypeResetDescription7-0RTLL11-RTLL4R/W00hThesebitsdeterminethevalueofhighbyteofthelowtemperaturelimittowhichtheremotetemperaturemeasurementiscompared.
TheresolutionoftheLSBinthisregisteris1°C.
7.
6.
1.
12One-shotStartRegister(offset:Read=N/A;Write=0Fh)[reset=N/A]Figure27.
One-shotStartRegister76543210XXXXXXXXWWWWWWWWLEGEND:R/W=Read/Write;R=Readonly;-n=valueafterreset22Copyright2013–2014,TexasInstrumentsIncorporatedTMP451www.
ti.
com.
cnZHCSB68A–JUNE2013–REVISEDDECEMBER2014Table14.
One-shotStartRegisterFieldDescriptionsBitFieldTypeResetDescription7-0XWN/AWhenthedeviceisintheshutdownmodewritinganyvaluetothisregisterwilltriggeraone-shottemperatureconversion.
7.
6.
1.
13RemoteTemperatureLowByteRegister(offset:Read=10h;Write=N/A)[reset=00h]Figure28.
RemoteTemperatureLowByteRegister76543210RT3RT2RT1RT0RESERVEDR-0hR-0hR-0hR-0hR-0hLEGEND:R/W=Read/Write;R=Readonly;-n=valueafterresetTable15.
RemoteTemperatureLowByteRegisterFieldDescriptionsBitFieldTypeResetDescription7-4RT3-RT0R0hRemotetemperaturelowbyte.
TheresolutionoftheLSBinthisregisteris0.
0625°C.
Thisregisterisread-onlyandisupdatedbytheADCeachtimeatemperaturemeasurementiscompleted.
Whenthefulltemperaturevalueisneeded,readingthehighbyteregisterfirstcausesthelowbyteregistervaluetobelocked(theADCdoesnotwritetoit)untilitisread.
Thesamethinghappensuponreadingthelowbyteregistervaluefirst(thehighbyteregistervalueislockeduntilitisread).
ThismechanismassuresthatbothbytesofthereadoperationarefromthesameADCconversion.
Thisassuranceremainsvalidonlyuntilanotherregisterisread.
Forproperoperation,readthehighbyteofthetemperatureresultfirst.
Readthelowbyteregisterinthenextreadcommand;ifthelowbyteisnotneeded,theregistermaybeleftunread.
Theresolutionofthesefourbitsis0.
0625°C.
7.
6.
1.
14RemoteTemperatureOffsetHighByteRegister(offset:Read=11h;Write=11h)[reset=00h]Figure29.
RemoteTemperatureOffsetHighByteRegister76543210RTOS11RTOS10RTOS9RTOS8RTOS7RTOS6RTOS5RTOS4R/W-0hR/W-0hR/W-0hR/W-0hR/W-0hR/W-0hR/W-0hR/W-0hLEGEND:R/W=Read/Write;R=Readonly;-n=valueafterresetTable16.
RemoteTemperatureOffsetHighByteRegisterFieldDescriptionsBitFieldTypeResetDescription7-0RTOS11-RTOS4R/W00hRemotetemperatureoffsethighbyte.
ThevalueofthisregisterisaddedtothevaluetheADCconversionwiththeresultstoredintheremotetemperatureregister.
ThisregisterisusedtoaddorsubtractatemperatureoffsetvaluetotheADCconversionresultinapplicationsrequiringcalibration.
TheresolutionoftheLSBinthisregisteris1°C.
TheoffsetregisterallowstheTMP451devicetostoreanysystemoffsetcompensationvaluethatmightbeobservedfromprecisioncalibration.
Thevalueintheregisterisstoredinthesameformatasthetemperatureresult,andisaddedtotheremotetemperatureresultuponeveryconversion.
Combinedwiththeη-factorcorrection,thisfunctionallowsforveryaccuratesystemcalibrationovertheentiretemperaturerange.
7.
6.
1.
15RemoteTemperatureOffsetLowByteRegister(offset:Read=12h;Write=12h)[reset=00h]Copyright2013–2014,TexasInstrumentsIncorporated23TMP451ZHCSB68A–JUNE2013–REVISEDDECEMBER2014www.
ti.
com.
cnFigure30.
RemoteTemperatureOffsetLowByteRegister76543210RTOS3RTOS2RTOS1RTOS0RESERVEDR/W-0hR/W-0hR/W-0hR/W-0hR/W-0hLEGEND:R/W=Read/Write;R=Readonly;-n=valueafterresetTable17.
RemoteTemperatureOffsetLowByteRegisterFieldDescriptionsBitFieldTypeResetDescription7-4RTOS3-RTOS0R/W0hRemotetemperatureoffsetlowbyte.
ThevalueofthisregisterisaddedtothevaluetheADCconversionwiththeresultstoredintheremotetemperatureregister.
ThisregisterisusedtoaddorsubtractatemperatureoffsetvaluetotheADCconversionresultinapplicationsrequiringcalibration.
Theresolutionofthesefourbitsis0.
0625°C.
TheoffsetregisterallowstheTMP451devicetostoreanysystemoffsetcompensationvaluethatmightbeobservedfromprecisioncalibration.
Thevalueintheregisterisstoredinthesameformatasthetemperatureresult,andisaddedtotheremotetemperatureresultuponeveryconversion.
Combinedwiththeη-factorcorrection,thisfunctionallowsforveryaccuratesystemcalibrationovertheentiretemperaturerange.
7.
6.
1.
16RemoteTemperatureHighLimitLowByteRegister(offset:Read=13h;Write=13h)[reset=00h]Figure31.
RemoteTemperatureHighLimitLowByteRegister76543210RTHL3RTHL2RTHL1RTHL0RESERVEDR/W-0hR/W-0hR/W-0hR/W-0hR/W-0hLEGEND:R/W=Read/Write;R=Readonly;-n=valueafterresetTable18.
RemoteTemperatureHighLimitLowByteRegisterFieldDescriptionsBitFieldTypeResetDescription7-4RTHL3-RTHL0R/W0hThesebitsdeterminethevalueofthelowbyteofthehightemperaturelimittowhichtheremotetemperaturemeasurementiscompared.
Theresolutionofthefourbitsinthisregisteris0.
0625°C.
7.
6.
1.
17RemoteTemperatureLowLimitLowByteRegister(offset:Read=14h;Write=14h)[reset=00h]Figure32.
RemoteTemperatureLowLimitLowByteRegister76543210RTLL3RTLL2RTLL1RTLL0RESERVEDR/W-0hR/W-0hR/W-0hR/W-0hR/W-0hLEGEND:R/W=Read/Write;R=Readonly;-n=valueafterresetTable19.
RemoteTemperatureLowLimitLowByteRegisterFieldDescriptionsBitFieldTypeResetDescription7-4RTLL3-RTLL0R/W0hThesebitsdeterminethevalueofthelowbyteofthelowtemperaturelimittowhichtheremotetemperaturemeasurementiscompared.
Theresolutionofthefourbitsinthisregisteris0.
0625°C.
24Copyright2013–2014,TexasInstrumentsIncorporatedTMP451www.
ti.
com.
cnZHCSB68A–JUNE2013–REVISEDDECEMBER20147.
6.
1.
18LocalTemperatureLowByteRegister(offset:Read=15h;Write=N/A)[reset=00h]Figure33.
LocalTemperatureLowByteRegister76543210LT3LT2TL1LT0RESERVEDR-0hR-0hR-0hR-0hR-0hLEGEND:R/W=Read/Write;R=Readonly;-n=valueafterresetTable20.
LocalTemperatureLowByteRegisterFieldDescriptionsBitFieldTypeResetDescription7-0LT3-LT0R0hLocaltemperaturelowbyte.
Theresolutionofthefourbitsinthisregisteris0.
0625C.
Thisregisterisread-onlyandisupdatedbytheADCeachtimeatemperaturemeasurementiscompleted.
Whenthefulltemperaturevalueisneeded,readingthehighbyteregisterfirstcausesthelowbyteregistervaluetobelocked(theADCdoesnotwritetoit)untilitisread.
Thesamethinghappensuponreadingthelowbyteregistervaluefirst(thehighbyteregistervalueislockeduntilitisread).
ThismechanismassuresthatbothbytesofthereadoperationarefromthesameADCconversion.
Thisassuranceremainsvalidonlyuntilanotherregisterisread.
Forproperoperation,readthehighbyteofthetemperatureresultfirst.
Readthelowbyteregisterinthenextreadcommand;ifthelowbyteisnotneeded,theregistermaybeleftunread.
7.
6.
1.
19RemoteTemperatureTHERMLimitRegister(offset:Read=19h;Write=19h)[reset=6C]Figure34.
RemoteTemperatureTHERMLimitRegister76543210RTH11RTH10RTH9RTH8RTH7RTH6RTH5RTH4R/W-0hR/W-1hR/W-1hR/W-0hR/W-1hR/W-1hR/W-0hR/W-0hLEGEND:R/W=Read/Write;R=Readonly;-n=valueafterresetTable21.
RemoteTemperatureTHERMLimitRegisterFieldDescriptionsBitFieldTypeResetDescription7-0RTH11-RTH4R/W6ChRemotetemperatureTHERMlimit.
ThesebitsdeterminethevalueoftheTHERMlimittowhichtheremotetemperaturemeasurementiscompared.
TheresolutionoftheLSBinthisregisteris1°C.
7.
6.
1.
20LocalTemperatureTHERMLimitRegister(offset:Read=20h;Write=20h)[reset=55]Figure35.
LocalTemperatureTHERMLimitRegister76543210LTH11LTH10LTH9LTH8LTH7LTH6LTH5LTH4R/W-0hR/W-1hR/W-0hR/W-1hR/W-0hR/W-1hR/W-0hR/W-1hLEGEND:R/W=Read/Write;R=Readonly;-n=valueafterresetTable22.
LocalTemperatureTHERMLimitRegisterFieldDescriptionsBitFieldTypeResetDescription7-0LTH11-LTH4R/W55hLocaltemperatureTHERMlimit.
ThesebitsdeterminethevalueoftheTHERMlimittowhichthelocaltemperaturemeasurementiscompared.
TheresolutionoftheLSBinthisregisteris1°C.
Copyright2013–2014,TexasInstrumentsIncorporated25TMP451ZHCSB68A–JUNE2013–REVISEDDECEMBER2014www.
ti.
com.
cn7.
6.
1.
21THERMHysteresisRegister(offset:Read=21h;Write=21h)[reset=0Ah]Figure36.
THERMHysteresisRegister76543210HYS11HYS10HYS9HYS8HYS7HYS6HYS5HYS4R/W-0hR/W-0hR/W-0hR/W-0hR/W-1hR/W-0hR/W-1hR/W-0hLEGEND:R/W=Read/Write;R=Readonly;-n=valueafterresetTable23.
THERMHysteresisRegisterFieldDescriptionsBitFieldTypeResetDescription7-0HYS11-HYS4R/W0AhTHERMhysteresisvalue.
ThesebitsdeterminetheamountofhysteresisappliedtotheTHERMfunction.
ThersolutionoftheLSBinthisregisteris1°C.
7.
6.
1.
22ConsecutiveALERTRegister(offset:Read=22h;Write=22h)[reset=01h]Figure37.
ConsecutiveALERTRegister76543210SMBTORESERVEDCONAL2CONAL1CONAL0RESERVEDR/W-0hR/W-0hR/W-0hR/W-0hR/W-0hR/W-1hLEGEND:R/W=Read/Write;R=Readonly;-n=valueafterresetTable24.
ConsecutiveALERTRegisterFieldDescriptionsBitFieldTypeResetDescription7SMBTOR/W0hSMBustime-outenableordisable.
RefertoTime-outFunction1=EnablestheSMBustime-outfeature.
0=DisablestheSMBustime-outfeature.
3-1CONAL2-CONAL1R/W0hNumberofconsecutiveout-of-limitmeasurementsrequiredtoactivatetheALERTflagandpinRefertoTable25Table25.
ConsecutiveAlertConfigurationVALUENumberofConsecutiveOut-of-limitMeasurementsRequired0h11h23h37h47.
6.
1.
23η-FactorCorrectionRegister(offset:Read=23h;Write=23h)[reset=00h]Figure38.
η-FactorCorrectionRegister76543210NC7NC6NC5NC4NC3NC2NC1NC0R/W-0hR/W-0hR/W-0hR/W-0hR/W-0hR/W-0hR/W-0hR/W-0hLEGEND:R/W=Read/Write;R=Readonly;-n=valueafterresetTable26.
η-FactorCorrectionRegisterFieldDescriptionsBitFieldTypeResetDescription7-0NC7-NC0R/W00hη-factorvalueRefertoTable2726Copyright2013–2014,TexasInstrumentsIncorporatedTMP451www.
ti.
com.
cnZHCSB68A–JUNE2013–REVISEDDECEMBER2014TheTMP451deviceallowsforadifferentη-factorvaluetobeusedforconvertingremotechannelmeasurementstotemperature.
TheremotechannelusessequentialcurrentexcitationtoextractadifferentialVBEvoltagemeasurementtodeterminethetemperatureoftheremotetransistor.
Equation1showsthisvoltageandtemperature.
(1)ThevalueηinEquation1isacharacteristicoftheparticulartransistorusedfortheremotechannel.
Thepower-onresetvaluefortheTMP451deviceisη=1.
008.
Thevalueintheη-factorcorrectionregistermaybeusedtoadjusttheeffectiveη-factoraccordingtoEquation2andEquation3.
(2)(3)Theη-factorcorrectionvaluemustbestoredintwoscomplementformat,yieldinganeffectivedatarangefrom–128to127.
Theη-factorcorrectionvalueiswrittentoandreadfrompointeraddress23h.
Theregisterpower-onresetvalueis00h,thushavingnoeffectunlessadifferentvalueiswrittentoit.
Table27.
η-FactorRangeNADJUSTBINARYHEXDECIMALη011111117F1270.
950198000010100A101.
003195000010000881.
004152000001100661.
005111000001000441.
006072000000100221.
007035000000010111.
007517000000000001.
00811111111FF–11.
00848311111110FE–21.
00896711111100FC–41.
00993511111010FA–61.
01090511111000F8–81.
01187711110110F6–101.
0128511000000080–1281.
0738377.
6.
1.
24DigitalFilterControlRegister(offset:Read=24h;Write=24h)[reset=00h]Figure39.
DigitalFilterControlRegister76543210RESERVEDDF1DF0R/W-0hR/W-0hR/W-0hLEGEND:R/W=Read/Write;R=Readonly;-n=valueafterresetTable28.
DigitalFilterControlRegisterFieldDescriptionsBitFieldTypeResetDescription1-0DF1-DF0R/W0hConfigurestheamountoffilteringfortheremotetemperatureresults.
RefertoTable29Copyright2013–2014,TexasInstrumentsIncorporated27TMP451ZHCSB68A–JUNE2013–REVISEDDECEMBER2014www.
ti.
com.
cnTable29.
DigitalFilterConfigurationVALUENumberofRemoteTemperatureMeasurementsAveraged0hAveragingoff1h42h84hnotused7.
6.
1.
25ManufacturerIDRegister(offset:Read=FEh;Write=N/A)[reset=55]Figure40.
ManufacturerIDRegister76543210ID7ID6ID5ID4ID3ID2ID1ID0R-0hR-1hR-0hR-1hR-0hR-1hR-0hR-1hLEGEND:R/W=Read/Write;R=Readonly;-n=valueafterresetTable30.
ManufacturerIDRegisterFieldDescriptionsBitFieldTypeResetDescription7-0ID7-ID0R55hManufactureridentificationinformationTheTMP451deviceallowsforthetwo-wirebuscontrollertoquerythedeviceformanufactureranddeviceIDstoenablesoftwareidentificationofthedeviceattheparticulartwo-wirebusaddress.
ThemanufacturerIDisobtainedbyreadingfrompointeraddressFEh.
TheTMP451devicereads55hforthemanufacturercode.
28Copyright2013–2014,TexasInstrumentsIncorporatedTMP451www.
ti.
com.
cnZHCSB68A–JUNE2013–REVISEDDECEMBER20148ApplicationandImplementationNOTEInformationinthefollowingapplicationssectionsisnotpartoftheTIcomponentspecification,andTIdoesnotwarrantitsaccuracyorcompleteness.
TI'scustomersareresponsiblefordeterminingsuitabilityofcomponentsfortheirpurposes.
Customersshouldvalidateandtesttheirdesignimplementationtoconfirmsystemfunctionality.
8.
1ApplicationInformationTheTMP451devicerequiresonlyatransistorconnectedbetweentheD+andD–pinsforremotetemperaturemeasurement.
TietheD+pintoGNDiftheremotechannelisnotusedandonlythelocaltemperatureismeasured.
TheSDA,ALERT,andTHERMpins(andSCL,ifdrivenbyanopen-drainoutput)requirepullupresistorsaspartofthecommunicationbus.
A0.
1-Fpower-supplydecouplingcapacitorisrecommendedforlocalbypassing.
8.
2TypicalApplicationFigure41showsthetypicalconfigurationfortheTMP451device.
(1)Diode-connectedconfigurationprovidesbettersettlingtime.
Transistor-connectedconfigurationprovidesbetterseriesresistancecancellation.
(2)RS(optional)shouldbe0.
25Vat7.
5μA,atthehighestsensedtemperature.
2.
Base-emittervoltage<0.
95Vat120μA,atthelowestsensedtemperature.
3.
Baseresistance<100.
4.
TightcontrolofVBEcharacteristicsindicatedbysmallvariationsinhFE(thatis,50to150).
Basedonthiscriteria,tworecommendedsmall-signaltransistorsarethe2N3904(NPN)or2N3906(PNP).
8.
2.
2DetailedDesignProcedureThelocaltemperaturesensorinsidetheTMP451devicemonitorstheambientairaroundthedevice.
ThethermaltimeconstantfortheTMP451deviceisapproximatelytwoseconds.
Thisconstantimpliesthatiftheambientairchangesquicklyby100°C,itwouldtaketheTMP451deviceabout10seconds(thatis,fivethermaltimeconstants)tosettletowithin1°Cofthefinalvalue.
Inmostapplications,theTMP451packageisinelectrical,andthereforethermal,contactwiththeprintedcircuitboard(PCB),aswellassubjectedtoforcedairflow.
TheaccuracyofthemeasuredtemperaturedirectlydependsonhowaccuratelythePCBandforcedairflowtemperaturesrepresentthetemperaturethattheTMP451ismeasuring.
Additionally,theinternalpowerdissipationoftheTMP451cancausethetemperaturetoriseabovetheambientorPCBtemperature.
Theinternalpowerdissipatedasaresultofexcitingtheremotetemperaturesensorisnegligiblebecauseofthesmallcurrentsused.
Fora3.
3-Vsupplyandmaximumconversionrateof16conversionspersecond,theTMP451devicedissipates0.
54mW(PDIQ=3.
3V*165μA).
AθJAof171.
3°C/Wcausesthejunctiontemperaturetoriseapproximately0.
09°Cabovetheambient.
ThetemperaturemeasurementaccuracyoftheTMP451devicedependsontheremoteand/orlocaltemperaturesensorbeingatthesametemperatureasthesystempointbeingmonitored.
Clearly,ifthetemperaturesensorisnotingoodthermalcontactwiththepartofthesystembeingmonitored,thentherewillbeadelayintheresponseofthesensortoatemperaturechangeinthesystem.
Forremotetemperature-sensingapplicationsusingasubstratetransistor(orasmall,SOT23transistor)placedclosetothedevicebeingmonitored,thisdelayisusuallynotaconcern.
8.
2.
3ApplicationCurvesThefollowingcurvesshowtheperformancecapabilitiesoftheTMP451device.
Figure43showstheaccuracyperformanceinanoil-bathtemperaturedriftofapopulationof16standrard2N3906transistorsmeasuredinadiode-connectedconfiguration.
Figure44showsthetypicalstepresponsetoasubmergingofasensorinanoilbathwithtemperatureof100°C.
Copyright2013–2014,TexasInstrumentsIncorporated31TMP451ZHCSB68A–JUNE2013–REVISEDDECEMBER2014www.
ti.
com.
cnTypicalApplication(continued)Figure44.
TemperatureStepResponseFigure43.
TMP451RemoteDiodeTemperatureDrift(Diode-Connected2N3906)9PowerSupplyRecommendationsTheTMP451deviceoperateswithapowersupplyrangeof1.
7Vto3.
6V.
Thedeviceisoptimizedforoperationat3.
3-Vsupplybutcanmeasuretemperatureaccuratelyinthefullsupplyrange.
Apower-supplybypasscapacitorisrecommended.
Placethiscapacitorascloseaspossibletothesupplyandgroundpinsofthedevice.
Atypicalvalueforthissupplybypasscapacitoris0.
1μF.
Applicationswithnoisyorhigh-impedancepowersuppliesmayrequireadditionaldecouplingcapacitorstorejectpower-supplynoise.
10Layout10.
1LayoutGuidelinesRemotetemperaturesensingontheTMP451devicemeasuresverysmallvoltagesusingverylowcurrents;therefore,noiseatthedeviceinputsmustbeminimized.
MostapplicationsusingtheTMP451havehighdigitalcontent,withseveralclocksandlogicleveltransitionscreatinganoisyenvironment.
Layoutshouldadheretothefollowingguidelines:1.
PlacetheTMP451deviceasclosetotheremotejunctionsensoraspossible.
2.
RoutetheD+andD–tracesnexttoeachotherandshieldthemfromadjacentsignalsthroughtheuseofgroundguardtraces;seeFigure45.
IfamultilayerPCBisused,burythesetracesbetweengroundorV+planestoshieldthemfromextrinsicnoisesources.
5mil(0.
127mm)PCBtracesarerecommended.
3.
Minimizeadditionalthermocouplejunctionscausedbycopper-to-solderconnections.
Ifthesejunctionsareused,makethesamenumberandapproximatelocationsofcopper-to-solderconnectionsinboththeD+andD–connectionstocancelanythermocoupleeffects.
4.
Usea0.
1μFlocalbypasscapacitordirectlybetweentheV+andGNDoftheTMP451device.
Foroptimummeasurementperformance,minimizefiltercapacitancebetweenD+andD–to1000pForless.
ThiscapacitanceincludesanycablecapacitancebetweentheremotetemperaturesensorandtheTMP451device.
5.
IftheconnectionbetweentheremotetemperaturesensorandtheTMP451deviceislessthan8-in(20,32cm)long,useatwisted-wirepairconnection.
Forlengthsgreaterthan8in,useatwisted,shieldedpairwiththeshieldgroundedasclosetotheTMP451deviceaspossible.
Leavetheremotesensorconnectionendoftheshieldwireopentoavoidgroundloopsand60-Hzpickup.
6.
ThoroughlycleanandremoveallfluxresidueinandaroundthepinsoftheTMP451devicetoavoidtemperatureoffsetreadingsasaresultofleakagepathsbetweenD+andGND,orbetweenD+andV+.
32Copyright2013–2014,TexasInstrumentsIncorporatedTMP451www.
ti.
com.
cnZHCSB68A–JUNE2013–REVISEDDECEMBER2014Useminimum5-mil(0.
127mm)traceswith5-milspacing.
Figure45.
SuggestedPCBLayerCross-Section10.
2LayoutExampleFigure46.
TMP451LayoutExample版权2013–2014,TexasInstrumentsIncorporated33TMP451ZHCSB68A–JUNE2013–REVISEDDECEMBER2014www.
ti.
com.
cn11器器件件和和文文档档支支持持11.
1商商标标SMBusisatrademarkofIntelCorporation.
Allothertrademarksarethepropertyoftheirrespectiveowners.
11.
2静静电电放放电电警警告告ESD可能会损坏该集成电路.
德州仪器(TI)建议通过适当的预防措施处理所有集成电路.
如果不遵守正确的处理措施和安装程序,可能会损坏集成电路.
ESD的损坏小至导致微小的性能降级,大至整个器件故障.
精密的集成电路可能更容易受到损坏,这是因为非常细微的参数更改都可能会导致器件与其发布的规格不相符.
11.
3术术语语表表SLYZ022—TI术语表.
这份术语表列出并解释术语、首字母缩略词和定义.
12机机械械封封装装和和可可订订购购信信息息以下页中包括机械封装和可订购信息.
这些信息是针对指定器件可提供的最新数据.
这些数据会在无通知且不对本文档进行修订的情况下发生改变.
欲获得该数据表的浏览器版本,请查阅左侧的导航栏.
34版权2013–2014,TexasInstrumentsIncorporated重重要要声声明明德州仪器(TI)及其下属子公司有权根据JESD46最新标准,对所提供的产品和服务进行更正、修改、增强、改进或其它更改,并有权根据JESD48最新标准中止提供任何产品和服务.
客户在下订单前应获取最新的相关信息,并验证这些信息是否完整且是最新的.
所有产品的销售都遵循在订单确认时所提供的TI销售条款与条件.
TI保证其所销售的组件的性能符合产品销售时TI半导体产品销售条件与条款的适用规范.
仅在TI保证的范围内,且TI认为有必要时才会使用测试或其它质量控制技术.
除非适用法律做出了硬性规定,否则没有必要对每种组件的所有参数进行测试.
TI对应用帮助或客户产品设计不承担任何义务.
客户应对其使用TI组件的产品和应用自行负责.
为尽量减小与客户产品和应用相关的风险,客户应提供充分的设计与操作安全措施.
TI不对任何TI专利权、版权、屏蔽作品权或其它与使用了TI组件或服务的组合设备、机器或流程相关的TI知识产权中授予的直接或隐含权限作出任何保证或解释.
TI所发布的与第三方产品或服务有关的信息,不能构成从TI获得使用这些产品或服务的许可、授权、或认可.
使用此类信息可能需要获得第三方的专利权或其它知识产权方面的许可,或是TI的专利权或其它知识产权方面的许可.
对于TI的产品手册或数据表中TI信息的重要部分,仅在没有对内容进行任何篡改且带有相关授权、条件、限制和声明的情况下才允许进行复制.
TI对此类篡改过的文件不承担任何责任或义务.
复制第三方的信息可能需要服从额外的限制条件.
在转售TI组件或服务时,如果对该组件或服务参数的陈述与TI标明的参数相比存在差异或虚假成分,则会失去相关TI组件或服务的所有明示或暗示授权,且这是不正当的、欺诈性商业行为.
TI对任何此类虚假陈述均不承担任何责任或义务.
客户认可并同意,尽管任何应用相关信息或支持仍可能由TI提供,但他们将独力负责满足与其产品及在其应用中使用TI产品相关的所有法律、法规和安全相关要求.
客户声明并同意,他们具备制定与实施安全措施所需的全部专业技术和知识,可预见故障的危险后果、监测故障及其后果、降低有可能造成人身伤害的故障的发生机率并采取适当的补救措施.
客户将全额赔偿因在此类安全关键应用中使用任何TI组件而对TI及其代理造成的任何损失.
在某些场合中,为了推进安全相关应用有可能对TI组件进行特别的促销.
TI的目标是利用此类组件帮助客户设计和创立其特有的可满足适用的功能安全性标准和要求的终端产品解决方案.
尽管如此,此类组件仍然服从这些条款.
TI组件未获得用于FDAClassIII(或类似的生命攸关医疗设备)的授权许可,除非各方授权官员已经达成了专门管控此类使用的特别协议.
只有那些TI特别注明属于军用等级或"增强型塑料"的TI组件才是设计或专门用于军事/航空应用或环境的.
购买者认可并同意,对并非指定面向军事或航空航天用途的TI组件进行军事或航空航天方面的应用,其风险由客户单独承担,并且由客户独力负责满足与此类使用相关的所有法律和法规要求.
TI已明确指定符合ISO/TS16949要求的产品,这些产品主要用于汽车.
在任何情况下,因使用非指定产品而无法达到ISO/TS16949要求,TI不承担任何责任.
产品应用数字音频www.
ti.
com.
cn/audio通信与电信www.
ti.
com.
cn/telecom放大器和线性器件www.
ti.
com.
cn/amplifiers计算机及周边www.
ti.
com.
cn/computer数据转换器www.
ti.
com.
cn/dataconverters消费电子www.
ti.
com/consumer-appsDLP产品www.
dlp.
com能源www.
ti.
com/energyDSP-数字信号处理器www.
ti.
com.
cn/dsp工业应用www.
ti.
com.
cn/industrial时钟和计时器www.
ti.
com.
cn/clockandtimers医疗电子www.
ti.
com.
cn/medical接口www.
ti.
com.
cn/interface安防应用www.
ti.
com.
cn/security逻辑www.
ti.
com.
cn/logic汽车电子www.
ti.
com.
cn/automotive电源管理www.
ti.
com.
cn/power视频和影像www.
ti.
com.
cn/video微控制器(MCU)www.
ti.
com.
cn/microcontrollersRFID系统www.
ti.
com.
cn/rfidsysOMAP应用处理器www.
ti.
com/omap无线连通性www.
ti.
com.
cn/wirelessconnectivity德州仪器在线技术支持社区www.
deyisupport.
comIMPORTANTNOTICE邮寄地址:上海市浦东新区世纪大道1568号,中建大厦32楼邮政编码:200122Copyright2014,德州仪器半导体技术(上海)有限公司PACKAGEOPTIONADDENDUMwww.
ti.
com10-Dec-2020Addendum-Page1PACKAGINGINFORMATIONOrderableDeviceStatus(1)PackageTypePackageDrawingPinsPackageQtyEcoPlan(2)Leadfinish/Ballmaterial(6)MSLPeakTemp(3)OpTemp(°C)DeviceMarking(4/5)SamplesTMP451AIDQFRACTIVEWSONDQF83000RoHS&GreenNIPDAULevel-1-260C-UNLIM-40to125T451TMP451AIDQFTACTIVEWSONDQF8250RoHS&GreenNIPDAULevel-1-260C-UNLIM-40to125T451(1)Themarketingstatusvaluesaredefinedasfollows:ACTIVE:Productdevicerecommendedfornewdesigns.
LIFEBUY:TIhasannouncedthatthedevicewillbediscontinued,andalifetime-buyperiodisineffect.
NRND:Notrecommendedfornewdesigns.
Deviceisinproductiontosupportexistingcustomers,butTIdoesnotrecommendusingthispartinanewdesign.
PREVIEW:Devicehasbeenannouncedbutisnotinproduction.
Samplesmayormaynotbeavailable.
OBSOLETE:TIhasdiscontinuedtheproductionofthedevice.
(2)RoHS:TIdefines"RoHS"tomeansemiconductorproductsthatarecompliantwiththecurrentEURoHSrequirementsforall10RoHSsubstances,includingtherequirementthatRoHSsubstancedonotexceed0.
1%byweightinhomogeneousmaterials.
Wheredesignedtobesolderedathightemperatures,"RoHS"productsaresuitableforuseinspecifiedlead-freeprocesses.
TImayreferencethesetypesofproductsas"Pb-Free".
RoHSExempt:TIdefines"RoHSExempt"tomeanproductsthatcontainleadbutarecompliantwithEURoHSpursuanttoaspecificEURoHSexemption.
Green:TIdefines"Green"tomeanthecontentofChlorine(Cl)andBromine(Br)basedflameretardantsmeetJS709Blowhalogenrequirementsof<=1000ppmthreshold.
Antimonytrioxidebasedflameretardantsmustalsomeetthe<=1000ppmthresholdrequirement.
(3)MSL,PeakTemp.
-TheMoistureSensitivityLevelratingaccordingtotheJEDECindustrystandardclassifications,andpeaksoldertemperature.
(4)Theremaybeadditionalmarking,whichrelatestothelogo,thelottracecodeinformation,ortheenvironmentalcategoryonthedevice.
(5)MultipleDeviceMarkingswillbeinsideparentheses.
OnlyoneDeviceMarkingcontainedinparenthesesandseparatedbya"~"willappearonadevice.
IfalineisindentedthenitisacontinuationofthepreviouslineandthetwocombinedrepresenttheentireDeviceMarkingforthatdevice.
(6)Leadfinish/Ballmaterial-OrderableDevicesmayhavemultiplematerialfinishoptions.
Finishoptionsareseparatedbyaverticalruledline.
Leadfinish/Ballmaterialvaluesmaywraptotwolinesifthefinishvalueexceedsthemaximumcolumnwidth.
ImportantInformationandDisclaimer:TheinformationprovidedonthispagerepresentsTI'sknowledgeandbeliefasofthedatethatitisprovided.
TIbasesitsknowledgeandbeliefoninformationprovidedbythirdparties,andmakesnorepresentationorwarrantyastotheaccuracyofsuchinformation.
Effortsareunderwaytobetterintegrateinformationfromthirdparties.
TIhastakenandcontinuestotakereasonablestepstoproviderepresentativeandaccurateinformationbutmaynothaveconducteddestructivetestingorchemicalanalysisonincomingmaterialsandchemicals.
TIandTIsuppliersconsidercertaininformationtobeproprietary,andthusCASnumbersandotherlimitedinformationmaynotbeavailableforrelease.
InnoeventshallTI'sliabilityarisingoutofsuchinformationexceedthetotalpurchasepriceoftheTIpart(s)atissueinthisdocumentsoldbyTItoCustomeronanannualbasis.
PACKAGEOPTIONADDENDUMwww.
ti.
com10-Dec-2020Addendum-Page2TAPEANDREELINFORMATION*AlldimensionsarenominalDevicePackageTypePackageDrawingPinsSPQReelDiameter(mm)ReelWidthW1(mm)A0(mm)B0(mm)K0(mm)P1(mm)W(mm)Pin1QuadrantTMP451AIDQFRWSONDQF83000180.
08.
42.
32.
31.
154.
08.
0Q2TMP451AIDQFRWSONDQF83000180.
08.
42.
22.
21.
24.
08.
0Q2TMP451AIDQFTWSONDQF8250180.
08.
42.
22.
21.
24.
08.
0Q2TMP451AIDQFTWSONDQF8250180.
08.
42.
32.
31.
154.
08.
0Q2PACKAGEMATERIALSINFORMATIONwww.
ti.
com5-Jan-2021PackMaterials-Page1*AlldimensionsarenominalDevicePackageTypePackageDrawingPinsSPQLength(mm)Width(mm)Height(mm)TMP451AIDQFRWSONDQF83000210.
0185.
035.
0TMP451AIDQFRWSONDQF83000200.
0183.
025.
0TMP451AIDQFTWSONDQF8250200.
0183.
025.
0TMP451AIDQFTWSONDQF8250210.
0185.
035.
0PACKAGEMATERIALSINFORMATIONwww.
ti.
com5-Jan-2021PackMaterials-Page2重要声明和免责声明TI提供技术和可靠性数据(包括数据表)、设计资源(包括参考设计)、应用或其他设计建议、网络工具、安全信息和其他资源,不保证没有瑕疵且不做出任何明示或暗示的担保,包括但不限于对适销性、某特定用途方面的适用性或不侵犯任何第三方知识产权的暗示担保.
这些资源可供使用TI产品进行设计的熟练开发人员使用.
您将自行承担以下全部责任:(1)针对您的应用选择合适的TI产品,(2)设计、验证并测试您的应用,(3)确保您的应用满足相应标准以及任何其他安全、安保或其他要求.
这些资源如有变更,恕不另行通知.
TI授权您仅可将这些资源用于研发本资源所述的TI产品的应用.
严禁对这些资源进行其他复制或展示.
您无权使用任何其他TI知识产权或任何第三方知识产权.
您应全额赔偿因在这些资源的使用中对TI及其代表造成的任何索赔、损害、成本、损失和债务,TI对此概不负责.
TI提供的产品受TI的销售条款(https:www.
ti.
com.
cn/zh-cn/legal/termsofsale.
html)或ti.
com.
cn上其他适用条款/TI产品随附的其他适用条款的约束.
TI提供这些资源并不会扩展或以其他方式更改TI针对TI产品发布的适用的担保或担保免责声明.
IMPORTANTNOTICE邮寄地址:上海市浦东新区世纪大道1568号中建大厦32楼,邮政编码:200122Copyright2021德州仪器半导体技术(上海)有限公司