外文文献翻译-以单片机为基础的低成本高性能半导体器件测试仪

12013NirmaUniversityInternationalConferenceonEngineering(NUiCONE)LowCostHighPerformanceMicrocontrollerBasedSemiconductorDeviceTesterKanadeJyotiSuresh1,KulkarniVishwashriAmrut21ElectronicsandTelecommunicationDept.JawaharlalNehruEngineeringCollege,Aurangabad,(M.S.)INDIA2ElectronicsandTelecommunicationDept.JawaharlalNehruEngineeringCollege,Aurangabad,(M.S.)INDIA1Kanade_,2AbstractThispaperdealswithdesignandimplementationofaversatiletestersystemfordiode,bipolarjunctiontransistor(BJT),andjunctionfieldeffecttransistor(JFET).ThebasicbuildingblocksforthistesterdesignincludePIC18F452microcontroller,analogmultiplexer/demultiplexer74HC4052,andLiquidCrystalDisplay(LCD).Thetestersystemdiscussedinthispaperprovideaccurateidentificationofsemiconductordeviceundertest(Diode,BJT,JFET),typesofbipolartransistor(NPN,PNP),typesofjunctionfieldeffecttransistor(NchannelJFET,PchannelJFET).Theproposedsystemalsodetectsleadsofdiode,bipolarjunctiontransistor(BJT),andjunctionfieldeffecttransistor(JFET).Apartfromthisthetesteralsomeasuresvariousparametersofabovementionedsemiconductordevicessuchasforwardvoltage(VF)andforwardcurrent(IF)fordiode,currentgain(HFE)forBJT,saturationcurrentwiththegateshortedtothesource(IDSS)forJFET.AllmeasurementandtestresultsareclearlyrepresentedonLCD.Lowpowerconsumption,simplehardware,userfriendlydesignandcompactsizearesalientfeaturesofthissemiconductordevicetester.KeywordsDiode,bipolarjunctiontransistor(BJT),junctionfieldeffecttransistor(JFET),PICmicrocontroller,currentgain.I.INTRODUCTIONSemiconductordevicesareusedinallthecurrentelectricalorelectronicsproductsonthemarket.Asaresultoftheincreasingdemandforsemiconductors,thesemiconductorindustryhasexperiencedsignificantgrowthoverthepast8to10years.Thesemiconductorindustryisoneofthemostproductiveanddynamicindustriesintheworld.Itintroducescontinuousandrapidadvancementintechnology,newdevicesandintegratedcircuits.Challengesthattheindustryisfacingaretocontinuouslyimproveproductandservicequalityandreliability,achievegreaterfunctionality,higherperformance,speedandzerodefects.Inordertomeetallthesechallengeselectronicproductsandintegratedcircuitsneedtobehighlytestable.Testingisaverycriticalcomponentoftheproductdevelopmentandproductionprocess.Itcanimproveproductsperformance,increasequalityandreliability,andlowerreturnrates.Therisingcostofelectronicsproducttestingisnowoneofthemainchallengestomanufacturers.Sometimescostoftestingcanbeevengreaterthanthecostofproductmanufacturingitself.Tomakeasignificantimpactonthecostoftestmayrequireachangeinteststrategywhichmayresultinbringinganew,lowercosttestplatform.Itisestimatedthatthecostoffailuredecreasestentimeswhenanerroriscaughtduringproductioninsteadofthefield,anddecreasestentimesagainifitiscaughtindesigninsteadofproduction.Hencetoreducemanufacturingcostandimproveyieldsemiconductordevicesshouldbetestedafterbeingfabricated.Thusbytakingintoaccountpracticalimportanceofabovementionedfactvaluableworkhasbeenaccomplishedindesigningnewversatiletestingschemeforsemiconductordevices.Afewdesignmethodologyofsemiconductordevicetesterhasbeenproposedinrecentdays1-8.InthispaperitisaimedtopresentaPIC18F452microcontrollerbasedsimple,lowcostsemiconductordevicetester.ThesoftwarecodingpartisdoneusingMPLABIDE.II.GENERALOVERVIEWOFPROPOSEDDESIGNBlockdiagramofsemiconductordevicetesterisasshowninFig.1.Itconsistof5blocksasPIC18F452microcontroller,LCD,analogmultiplexer74HC4052,resistorbankanddeviceundertestwhichinteractwitheachotherasfollows:microcontrollerapplies+5Vorgroundpotentialtotheleadsofunknowndevicethroughsuitableresistorintheresistorbankandalsoperformsnecessaryvoltagemeasurementsforfurthertestsandparametercalculations.S1,S2representsselectlinesformux1,S3,S4formux2andS5,S6formux3.Thepurposeofselectlinesistomakeproperchoiceofresistorvaluesinresistorbankwiththehelpofanalogmultiplexer.Allmeasurementandtestresultsforthedeviceundertestareclearlyrepresentedonliquidcrystaldisplayunit.Detaileddescriptionofeachblockisgivenbelow.A.MicrocontrollerMicrocontrolleremployedisMicrochipsPIC18F452.Fewofitsbuiltinfeaturesareasfollows:Ithaslinearprogrammemoryaddressingto32Kbytes,lineardatamemoryaddressingto1.5Kbytes,5I/Oports,10bitanalogtodigitalconverter(ADC)modulehaving8inputchannels,parallelslaveport(PSP),analogcomparator(AC).B.ResistorBankResistorbankconsistsof3resistorsofvalues1K,100and150K.Suitableresistorvaluesareselectedonthebasisoftypeoftestproceduretobecarriedoutonadeviceundertest.978-1-4799-0727-4/13/$31.002013IEEE2Fig.1Blockdiagramofsemiconductordevicetester.C.AnalogSwitch74HC4052Itisdual4channelanalogmultiplexer/demultiplexerwithcommonselectlogic.Itplaysveryimportantroleinmakingdesignofsemiconductordevicetestermoreuserfriendly.D.LCDInthissystem16x2characterliquidcrystaldisplayisusedtoprinttestandmeasurementresultsfortransistoranddiode.III.MEASUREMENTTECHNIQUEANDELECTRONICHARDWAREOFTHETESTERMicrocontrollerstartsitstestschedulebyperformingveryfirsttesttodeterminewhetherdeviceundertestistwoleaddevicethatisdiode.Diodecanbeconnectedbetweentestterminalsoneandthree.ThetestisbasedonthebasicconceptthatisPNjunctionconductscurrentinonlyonedirection3.InthistestMicrocontrollerapplies5Vtotheleadofdiodeconnectedtotestterminal1via1Kresistor.Theleadofdiodeconnectedtotestterminal3isgroundedthroughsameresistorvaluethatis1K.Microcontrollermeasuresvoltageacross1Kresistorconnectedtotestterminal3throughswitchandstoresmeasuredvalue.Onemoremeasurementofthissortismadewithdifferentleadsequence.Microcontrollerperformssomelogicaloperationsonthesetwomeasuredvaluestogetfinalresult.Nowtherearetwowaysinwhichdiodecanbeconnectedbetweentestterminalsoneandthreethatiscathodefacingtowardsterminalthreeandcathodefacingtowardsterminalone.Nowsametestsequenceisrepeatedfordiodeconnectedinanotherwaytogetonemorefinalresult.Thusbasedonthesetworesultmicrocontrollerdetermineswhetherdeviceundertestisdiodeoranyotherdevice.Thistestisalsosufficienttolocateanodeandcathodeleadsofdiode.Afteridentificationofdiodeleadsitsforwardvoltageiscalculatedbymakingnecessaryanalogvoltagemeasurementsandcalculations.TableIrepresentstheoreticallogictolocateanodeandcathodeleadsfordiode.Inthistablepotentialvaluesappliedandmeasuredattestterminalsoneandthreearerepresentedintermsoflogiclevels1and0.Intwoconditionsmicrocontrollerexecutesprogrammefortesting3leaddevicesthataretransistor.Thefirstconditionisthatifthetestfordiodefailsandthesecondconditionisthatifthetestfordiodeispositiveandvoltageoftestterminal(TT)2isnotzero.Microcontrollerchecksthesecondconditiontoavoidwrongidentificationofdeviceundertest.Incaseoftransistormicrocontrollerconductsfirsttestbyperformingvoltagemeasurementtodeterminewhetherconnecteddeviceisbipolarjunctiontransistororjunctionfieldeffecttransistor.Thesamelogicfortestingdiodecanbeextendedtotesttransistor;astransistoralsoconsistofPNjunctionswhichconductcurrentinonlyonedirection;thusbyconsideringthedirectionofcurrentconductiononecandeterminewhetherthetransistorundertestisbipolartransistororjunctionfieldeffecttransistor.Thistestisrealisedbyconnectingoneofthethreeleadsoftransistorto5Vthrough100resistanceandothertwoleadsareconnectedtogroundpotentialthrough1Kresistance;theirvoltagesarethendigitallyreadintheformoflogiclevels0and1.Thisprocesscanberepeatedforothertwoleadsequences.TABLEILOGICOFDETECTINGANODEANDCATHODELEADSOFDIODEVoltageappliedtotestVoltagemeasuredacrossVoltageappliedtotestVoltagemeasuredacrossRemarksterminal(TT)through1Kresistorconnectedterminal(TT)through1Kresistorconnected1KresistorintermstoTT3intermsoflogic1KresistorintermstoTT1intermsoflogicoflogiclevels0and1levels0and1oflogiclevels0and1levels0and1TT1TT3TT1TT3101010TT1-Anode,TT3-Cathode100011TT1-Cathode,TT3-AnodeEachtimemicrocontrollerstoresmeasuredvoltagevaluesandperformssomelogicaloperationsonthem.Nowtransistorcanbeconnectedinbetweenthreetestterminalsinsixways,sothetestsequenceisrepeatedforthatmanytimes.TheanalysisshowsauniquehexdatacorrespondingtoNPNBJTandNchannelJFET;whilethedatacorrespondingtoPNPBJTandPchannelJFETissamethereforeonceitisrecognizedthatthedeviceundertestisPNPBJTorPchannelJFETitisfurthersubjectedtoatestthatdifferentiatesPNPBJTfromPchannelJFET.ThefirsttestisalsosufficienttodeterminebaseleadofBJTandgateleadofJFET.AfteridentificationofbaseleadthetaskremainedistoidentifytheothertwoleadsofBJTthatarecollectorandemitter.Inaproperlybiasedtransistorthecurrentgainfrombasetocollectorismuchhigherthanbasetoemitter.Thispropertycanbeusedtoidentifytheactualcollectorleadoftransistor.Forthiscircuitisconnectedincommonemitterconfiguration,basecurrentisappliedandtheassumedcollectorisconnectedtosupplythroughaleadresistorof1K.Ifitisrealcollectorthecurrentgainwillbehigh,collectorcurrentwillbehighandcollectorvoltagewillbelow.Repeatingthisprocessforotherleadandcomparingthecollectorvoltageonecandecidetheactualcollectorlead.Oncethecollectorleadisidentifiedaproperbiasingisappliedchoosingsuitablecollectorandbaseresistorsthroughthemux.Theanalogvoltagesatcollectorandbaseterminalsaremeasuredusinganalogtodigitalconverters.Thecollectorcurrentandbasecurrentarecalculatedbymeasuringvoltagesacrossthecollectorandbaseresistancesandcurrentgainiscalculated.Configurationsusedformeasurementofforwardvoltageandforwardcurrentfordiode,currentgainforNPNBJT,andIDSSforNchannelJFETareshowninFig.2.3Fig.2MeasurementconfigurationsRSWITCHrepresentsinternalresistanceofswitchesofanalogmux/demux74HC4052.Itsvalueisapproximately65.MostofJFETsaresymmetricalinnaturethatistheirsourceanddrainterminalscanbeinterchangedhencethetestercanidentifyonlygateleadofJFETandothertwoleadscanbeassumedassourceanddrainwithoutalteringtheresultsrelatedtothecalculationofitsparameters5.OncethegateleadisidentifiedJFETisproperlybiasedandsaturationcurrentwiththegateshortedtothesource(IDSS)iscalculatedforVGS=0V.OperationalflowoftesterisgiveninFig.3.Fig.3Operationflowchartofsemiconductordevicetester4Fig.4showsthecircuitdiagramofthesemiconductordevicetester.A5Vpowersupplyisallthatrequiredfortheworkingofcircuit.Theexternalcrystalof12MHzisusedasclocksource.Intheproposedmoduledeviceundertestissubjectedtolargenoofpermutationsandcombinationsoflogiclevelsinperfectsequencethroughsuitableresistorvalues.Withoutremovingdeviceundertestthisispossibleifandonlyifanalogswitchesareusedforproperroutingofsignal.Threeanalogtodigitalconverterinputchannelsareusedtomakenecessaryanalogvoltagemeasurements.TheLCDpanelcommunicateswiththemicrocontrollerin8bitmode.Currentflowingthroughdeviceterminalhastopassthroughtheselectedseriesresistanceandinternalresistanceofanalogswitch.Thecurrentiscalculatedbymeasuringthepotentialdifferenceacrossseriesresistance;thereforesecondanalogswitchof74HC4052isusedtoconnectpotentialofotherleadofseriesresistortoanaloginputofmicrocontroller.Inputimpedanceofanaloginputofmicrocontrollerisalwaysextremelyhighhencenocurrentflowsthroughtheinternalresistanceofsecondswitchandallthevoltageatdesiredpointiscoupledtoanaloginputofmicrocontroller.Thustheeffectofinternalresistanceofanalogswitchcanbecompensatedtosomeextentwhilemakingcurrentmeasurements.Fig.4Circuitdiagramofsemiconductordevicetester.IVTESTRESULTSOFTHESEMICONDUCTORDEVICETESTERFig.5andFig.6illustrateresultsdisplayedonLCDpanelwhiletestingsemiconductordevices.Fig.5showstestresultsfordiode.Firstlineofdisplayindicatesforwardcurrentfordiodeandsecondlineofdisplayindicatesleadarrangementandforwardvoltagefordiode.Fig.6showstestresultsforbipolarjunctiontransistor.FirstlineofthedisplayindicatesthetypeofBJTanditscurrentgainHFE.Secondlineofdisplayindicatesitsleadarrangementandcollectorcurrent.Fig.5Testresultsfordiode.ThetestersdisplayindicatesDIODE;If=1.6mA;1-A3K;Vf=0.66VFig.6Testresultsforbipolartransistor.ThetestersdisplayindicatesBJT;NPN;hfe=176;EBC;Ic=3.52mA.5VCONCLUSIONANDFUTUREWORKBytakingintoaccountimmensepracticalimportanceoftestingsemiconductordevicesespeciallydiode,bipolarjunctiontransistorandjunctionfieldeffecttransistorasimple,lowcosttestingschemeispresentedinthispaper.Theproposedmodulecanfurtherbedevelopedtotestmetaloxidesemiconductorfieldeffecttransistor(MOSFET)andcalculateadditionalparameterssuchascutoffvoltage(VGSOFF),draintosourceonresistance(RDSON)ofJFETandthresholdvoltage(VTH)ofMOSFETwithfewmodificationsinsoftwareandhardware.REFERENCES1I.Lita,M.Jurian,D.A.Visan,S.Opera,andI.B.Cioc,“MicrocontrollerbasedtesterforsemiconductorDevices,”ElectronicsTechnology,31stInternationalSpringSeminar,ISSE08,pp.117-120,May7-11,2008.2R.L.BoylestadandL.Nasheisky,ElectronicDevicesandCircuitTheory,10thed.,PearsonEducationSouthAsia,India,2009.3T.L.Floyd,ElectronicDevices,7thed.,PearsonEducationSouthAsia,India,2008.4R.Gaonkar,FundamentalsofMicrocontrollersandApplicationsinEmbeddedSystems(withthePIC18MicrocontrollerFamily),PenramInternationalIndia,2007.5A.S.SedraandK.C.Smith,MicroelectronicCircuits,5thed.,OxfordUniversityPress.6“Microcontroller”datasheet.online.Available:/downloads/en/devicedoc/39564.pdf7“74HC4052”datasheet.online.Available:/documents/data_sheet/74HC_HCT4052.pdf.8TheELEKTORwebsite.online.Available:/以单片机为基础的低成本高性能半导体器件测试仪摘要本文旨在设计和实现的万能测试机系统能测试二极管，双极型晶体管(BJT)，结面型场效应晶体管(JFET)。这种测试机的基本构建块包括了PLC18F452微控制器，模拟多路复用器/解复用器74HC4052和液晶显示器(LCD)。本文讨论了该测试系统能准确识别半导体器件(如Diode，BJT，JFET)，能识别双极型晶体管的类型(NPN型、PNP型)，能识别结面型场效应晶体管类型(N通道JFET，P通道JFET)。该测试系统还能发现二极管，双极结晶体管(BJT)和结面型场效应晶体管(JFET)的引线。该测试仪除了能测试上面提到的各种半导体器件外还能测量各种参数如二极管正向电压(VF)和正向电流(IF)，BJT的电流增益(HFE)，面结型场效应管（JEFT）源极空载时的饱和电流(IDSS)。所有的测量和测试结果由显示屏LCD进行清晰的显示。低功耗，硬件简单，用户界面设计友好和精巧的尺寸是该半导体器件测试仪的特征。关键词：二极管、双极型晶体管(BJT)、面结型场效应管(JFET)、PLC微控制器、电流增益I简介半导体器件用于现今所有的电气或电子产品市场。随着半导体需求的增加，半导体行业在过去的8到10年里经历了显著地成长。半导体产业是世界上最富有成效的和活力的行业之一。它推动了技术、新设备和集成电路的持续和快速发展。行业所面临的挑战是，不断提高产品和服务的质量及产品可靠性，以实现更大的功能、更高的性能及高速度和零缺陷。为了满足所有这些挑战电子产品和集成电路必须要有高度的可测试性。测试是一个在产品开发和生产过程中非常关键的部分。它可以提高产品的性能，提高产品的质量和可靠性，并降低价格。目前对于制造商来说电子产品测试成本的上升是一个主要的挑战。有时测试成本甚至大于产品制造的成本本身。为了对测试成本产生一个重大的影响则可能需要改变测试策略，这样才有可能带来一个新的、成本更低的测试平台。据估计，当一个错误在生产过程中被替代时失败的代价会降低10倍，而如果是在设计过程将错误替代掉则代价会再降低10倍。因此为了减少生产成本和提高产量应当制造出半导体器件测试仪。因此考虑到上述提到的事实的实际意义中所应有的工作价值后已经设计出了新的半导体器件通用测试方案。在最近几天里将提出一些半导体器件测试仪的设计方法。本文旨在提供一个基于PLC18F452微控制器的简单的、成本低的半导体器件测试仪。软件编码部分使用的是MPLABIDE。II设计的总体概述半导体器件测试框图是如图1所示。它由5个模块PLC18F452微控制器、显示屏LCD、模拟多路转换器74HC4052、电阻器件及在测试设备的相互作用下组成，单片机应用5V的电压或接地电位而使未知设备通过电阻器组并执行必要的进一步测试电压的测量和参数的计算。S1，S2表示为mux1选择的线路,S3，S4表示为mux2选择的线路和S5，S6表示mux3选择的线路。模拟多路复用器选择线路的目的是为了在电阻器组的帮助下能选择出正确的电阻值。所有的测量和测试设备的测试结果清晰地显示液晶显示屏上。每个模块的详细描述将在下面给出。A单片机单片机采用的是PLC18452芯片，其内置的部分特征如下：它的程序存储器寻址范围为32KB，数字存储寻址范围为1.5字节，5个I/O端口，内置的10位模拟数字转换器（ADC）共有8个输入通道，并行从动端口（PSP），模拟比较器（AC）。B电阻器电阻器包括阻值为1K、10K、150K的三部分电阻，根据测试程序选择合适的电阻并在测试设备上进行测试。C模拟开关74HC4052这是双4通道模拟多路复用器/解复用器拥有常见的选择逻辑，它在制造半导体器件测试仪的中起着非常重要的作用从而使用户设计更加友好。D液晶显示器在这个系统中使用的是16x2字符的液晶显示，用于显示晶体管和二极管的测试和测量结果。III测量技术和电子测试仪的硬件微控制器最开始的步骤是通过执行第一次测试来确定设备是否在测试之下是一个双引线装置的二极管。二极管可以连接的测试端子在1和3之间。该试验基于PN结中只有一个方向的传导电流这一基本概念上。该试验中单片机采用5V电压使二极管的引线通过1K的电阻连接到测试终图1半导体器件测试框图端1。而连接到测试终端3的二极管引线是通过同一个1K电阻值连接到地。单片机经1K的电阻连接到测试端子3再连接开关来测试电压并存储测量值。这一类的更多的测量可由不同的引线序列来完成。微控制器对这两个测量值进行逻辑运算以获得最终结果。现在有两种方式，在该二极管可以连接的1和3测试端子之间有阴极朝向端子3和阴极朝向端子1。现在，二极管以另一种方式连接使相同的测试序列重复从而得到一个更最终的结果。因此，基于这两个结果微控制器确定被测设备是否是二极管或是任何其它装置。这个测试也足以用来确定二极管阳极和阴极的引线。当二极管的引线被识别后通过进行必要的模拟电压测量和计算可得出二极管的正向电压。表1表示了定位二极管阳极和阴极引线的逻辑理论。在这个表中，测试端口1和3三的应用和测量电平值表示为逻辑1和0。在两种条件下单片机执行的是晶体管设备测试3的程序。第一个条件是，如果二极管的测试失败，其次是，如果二极管的测试是正向的并且测试终端（TT）2的电压不为零。单片机检查第二个条件是为了避免在测试下的设备识别有错误。在测试晶体管时微控制器首先进行电压测量，以确定相连的设备是否是双极结