位-ad574a转换器中英文翻译资料

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1、英文原文12-BitA/DConverterCIRCUITOPERATIONTheAD574Aisacomplete12-bitA/Dconverterwhichrequiresnoexternalcomponentstoprovidethecompletesuccessiveapproximationanalog-to-digitalconversionfunction.AblockdiagramoftheAD574AisshowninFigure1.Figure1.BlockDiagramofAD574A12-BitA-to-DConverterWhenth

2、econtrolsectioniscommandedtoinitiateaconversion(asdescribedlater),itenablestheclockandresetsthesuccessiveapproximationregister(SAR)toallzeros.Onceaconversioncyclehasbegun,itcannotbestoppedorrestartedanddataisnotavailablefromtheoutputbuffers.TheSAR,timedbytheclock,willsequencethrought

3、heconversioncycleandreturnanend-of-convertflagtothecontrolsection.Thecontrolsectionwillthendisabletheclock,bringtheoutputstatusflaglow,andenablecontrolfunctionstoallowdatareadfunctionsbyexternalcommand.Duringtheconversioncycle,theinternal12-bitcurrentoutputDACissequencedbytheSARfromt

4、hemostsignificantbit(MSB)toleastsignificantbit(LSB)toprovideanoutputcurrentwhichaccuratelybalancestheinputsignalcurrentthroughthe5kΩ(or10kΩ)inputresistor.Thecomparatordetermineswhethertheadditionofeachsuccessively-weightedbitcurrentcausestheDACcurrentsumtobegreaterorlessthantheinputc

5、urrent;ifthesumisless,thebitislefton;ifmore,thebitisturnedoff.Aftertestingallthebits,theSARcontainsa12-bitbinarycodewhichaccuratelyrepresentstheinputsignaltowithin1/2LSB.Thetemperature-compensatedburiedZenerreferenceprovidestheprimaryvoltagereferencetotheDACandguaranteesexcellentstab

6、ilitywithbothtimeandtemperature.Thereferenceistrimmedto10.00volts±0.2%;itcansupplyupto1.5mAtoanexternalloadinadditiontotherequirementsofthereferenceinputresistor(0.5mA)andbipolaroffsetresistor(1mA)whentheAD574Aispoweredfrom±15Vsupplies.IftheAD574Aisusedwith±12Vsupplies,orifexternalcu

7、rrentmustbesuppliedoverthefulltemperaturerange,anexternalbufferamplifierisrecommended.AnyexternalloadontheAD574Areferencemustremainconstantduringconversion.Thethin-filmapplicationresistorsaretrimmedtomatchthefull-scaleoutputcurrentoftheDAC.Therearetwo5kWinputscalingresistorstoallowei

8、thera10volto