集成电路设计工具软件简介.ppt

集成电路设计技术 云南大学信息学院电子工程系 梁竹关 Part1SPICEOverview 集成电路仿真 SPICE History SPICE SimulationProgramwithIntegratedCircuitEmphasis isafamilyofprograms freewareorcommercial forsimulationofelectroniccircuits everyonebasedonthesamekernelthatisdevelopedbyBerkeleyUniversity California USA since1960withpublicfounds Fromthebeginningthereweremanyreleases wecanmentionSPICE2 thefirstwithpowerfulmodelsforsemiconductors andthecurrentSPICE3 sourcecodefromFortrantoC moreportabilityandefficiency Today scommercialpackagesaddtoitmanyfunctionsandfeatures graphicalandeasy to usefront ends powerfulpost processors integrationwithotherutilities newbuilt inmodels commandsandfunctions Thecodeproducedbythesesimulatorisnolongercompatiblewiththeoriginalkernel Part2TypesofAnalysis DCAnalysis ThedcanalysisportionofSPICEdeterminesthedcoperatingpointofthecircuitwithinductorsshortedandcapacitorsopened Thedcanalysisoptionsarespecifiedonthe DC TF and OPcontrollines Adcanalysisisautomaticallyperformedpriortoatransientanalysistodeterminethetransientinitialconditions andpriortoanacsmall signalanalysistodeterminethelinearized small signalmodelsfornonlineardevices Ifrequested thedcsmall signalvalueofatransferfunction ratioofoutputvariabletoinputsource inputresistance andoutputresistanceisalsocomputedasapartofthedcsolution Thedcanalysiscanalsobeusedtogeneratedctransfercurves aspecifiedindependentvoltageorcurrentsourceissteppedoverauser specifiedrangeandthedcoutputvariablesarestoredforeachsequentialsourcevalue ACSmall SignalAnalysis Theacsmall signalportionofSPICEcomputestheacoutputvariablesasafunctionoffrequency Theprogramfirstcomputesthedcoperatingpointofthecircuitanddetermineslinearized small signalmodelsforallofthenonlineardevicesinthecircuit Theresultantlinearcircuitisthenanalyzedoverauser specifiedrangeoffrequencies Thedesiredoutputofanacsmall signalanalysisisusuallyatransferfunction voltagegain transimpedance etc Ifthecircuithasonlyoneacinput itisconvenienttosetthatinputtounityandzerophase sothatoutputvariableshavethesamevalueasthetransferfunctionoftheoutputvariablewithrespecttotheinput TransientAnalysis ThetransientanalysisportionofSPICEcomputesthetransientoutputvariablesasafunctionoftimeoverauser specifiedtimeinterval Theinitialconditionsareautomaticallydeterminedbyadcanalysis Allsourceswhicharenottimedependent forexample powersupplies aresettotheirdcvalue Thetransienttimeintervalisspecifiedona TRANcontrolline Pole ZeroAnalysis Thepole zeroanalysisportionofSPICEcomputesthepolesand orzerosinthesmall signalactransferfunction Theprogramfirstcomputesthedcoperatingpointandthendeterminesthelinearized small signalmodelsforallthenonlineardevicesinthecircuit Thiscircuitisthenusedtofindthepolesandzerosofthetransferfunction Twotypesoftransferfunctionsareallowed oneoftheform outputvoltage inputvoltage andtheotheroftheform outputvoltage inputcurrent Thesetwotypesoftransferfunctionscoverallthecasesandonecanfindthepoles zerosoffunctionslikeinput outputimpedanceandvoltagegain Theinputandoutputportsarespecifiedastwopairsofnodes Thepole zeroanalysisworkswithresistors capacitors inductors linear controlledsources independentsources BJTs MOSFETs JFETsanddiodes Transmissionlinesarenotsupported Themethodusedintheanalysisisasub optimalnumericalsearch Forlargecircuitsitmaytakeaconsiderabletimeorfailtofindallpolesandzeros Forsomecircuits themethodbecomes lost andfindsanexcessivenumberofpolesorzeros Small SignalDistortionAnalysis ThedistortionanalysisportionofSPICEcomputessteady stateharmonicandintermodulationproductsforsmallinputsignalmagnitudes Ifsignalsofasinglefrequencyarespecifiedastheinputtothecircuit thecomplexvaluesofthesecondandthirdharmonicsaredeterminedateverypointinthecircuit Iftherearesignalsoftwofrequenciesinputtothecircuit theanalysisfindsoutthecomplexvaluesofthecircuitvariablesatthesumanddifferenceoftheinputfrequencies andatthedifferenceofthesmallerfrequencyfromthesecondharmonicofthelargerfrequency Distortionanalysisissupportedforthefollowingnonlineardevices diodes DIO BJT JFET MOSFETs levels1 2 3 4 BSIM1 5 BSIM2 and6 andMESFETS Alllineardevicesareautomaticallysupportedbydistortionanalysis Ifthereareswitchespresentinthecircuit theanalysiscontinuestobeaccurateprovidedtheswitchesdonotchangestateunderthesmallexcitationsusedfordistortioncalculations SensitivityAnalysis Spice3willcalculateeithertheDCoperating pointsensitivityortheACsmall signalsensitivityofanoutputvariablewithrespecttoallcircuitvariables includingmodelparameters Spicecalculatesthedifferenceinanoutputvariable eitheranodevoltageorabranchcurrent byperturbingeachparameterofeachdeviceindependently Sincethemethodisanumericalapproximation theresultsmaydemonstratesecondorderaffectsinhighlysensitiveparameters ormayfailtoshowverylowbutnon zerosensitivity Further sinceeachvariableisperturbbyasmallfractionofitsvalue zero valuedparametersarenotanalyzed thishasthebenefitofreducingwhatisusuallyaverylargeamountofdata NoiseAnalysis ThenoiseanalysisportionofSPICEdoesanalysisdevice generatednoiseforthegivencircuit Whenprovidedwithaninputsourceandanoutputport theanalysiscalculatesthenoisecontributionsofeachdevice andeachnoisegeneratorwithinthedevice totheoutputportvoltage Italsocalculatestheinputnoisetothecircuit equivalenttotheoutputnoisereferredtothespecifiedinputsource Thisisdoneforeveryfrequencypointinaspecifiedrange thecalculatedvalueofthenoisecorrespondstothespectraldensityofthecircuitvariableviewedasastationarygaussianstochasticprocess Aftercalculatingthespectraldensities noiseanalysisintegratesthesevaluesoverthespecifiedfrequencyrangetoarriveatthetotalnoisevoltage current overthisfrequencyrange Thiscalculatedvaluecorrespondstothevarianceofthecircuitvariableviewedasastationarygaussianprocess Part3CircuitDescriptions GENERALSTRUCTUREANDCONVENTIONS ThecircuittobeanalyzedisdescribedtoSPICEbyasetofelementlines whichdefinethecircuittopologyandelementvalues andasetofcontrollines whichdefinethemodelparametersandtheruncontrols Thefirstlineintheinputfilemustbethetitle andthelastlinemustbe END Theorderoftheremaininglinesisarbitrary except ofcourse thatcontinuationlinesmustimmediatelyfollowthelinebeingcontinued GENERALSTRUCTUREANDCONVENTIONS Eachelementinthecircuitisspecifiedbyanelementlinethatcontainstheelementname thecircuitnodestowhichtheelementisconnected andthevaluesoftheparametersthatdeterminetheelectricalcharacteristicsoftheelement Thefirstletteroftheelementnamespecifiestheelementtype TheformatfortheSPICEelementtypesisgiveninwhatfollows ThestringsXXXXXXX YYYYYYY andZZZZZZZdenotearbitraryalphanumericstrings Forexample aresistornamemustbeginwiththeletterRandcancontainoneormorecharacters Hence R R1 RSE ROUT andR3AC2ZYarevalidresistornames Detailsofeachtypeofdevicearesuppliedinafollowingsection GENERALSTRUCTUREANDCONVENTIONS Fieldsonalineareseparatedbyoneormoreblanks acomma anequal sign oraleftorrightparenthesis extraspacesareignored Alinemaybecontinuedbyenteringa plus incolumn1ofthefollowingline SPICEcontinuesreadingbeginningwithcolumn2 Anamefieldmustbeginwithaletter AthroughZ andcannotcontainanydelimiters GENERALSTRUCTUREANDCONVENTIONS Anumberfieldmaybeanintegerfield 12 44 afloatingpointfield 3 14159 eitheranintegerorfloatingpointnumberfollowedbyanintegerexponent 1e 14 2 65e3 oreitheranintegerorafloatingpointnumberfollowedbyoneofthefollowingscalefactors T 1012G 109Meg 106K 103mil 25 410 6m 10 3u 10 6n 10 9p 10 12f 10 15Lettersimmediatelyfollowinganumberthatarenotscalefactorsareignored andlettersimmediatelyfollowingascalefactorareignored Hence 10 10V 10Volts and10Hzallrepresentthesamenumber andM MA MSec andMMhosallrepresentthesamescalefactor Notethat1000 1000 0 1000Hz 1e3 1 0e3 1KHz and1Kallrepresentthesamenumber GENERALSTRUCTUREANDCONVENTIONS Nodesnamesmaybearbitrarycharacterstrings Thedatum ground nodemustbenamed 0 NotethedifferenceinSPICE3wherethenodesaretreatedascharacterstringsandnotevaluatedasnumbers thus 0 and 00 aredistinctnodesinSPICE3butnotinSPICE2 Thecircuitcannotcontainaloopofvoltagesourcesand orinductorsandcannotcontainacut setofcurrentsourcesand orcapacitors Eachnodeinthecircuitmusthaveadcpathtoground Everynodemusthaveatleasttwoconnectionsexceptfortransmissionlinenodes topermitunterminatedtransmissionlines andMOSFETsubstratenodes whichhavetwointernalconnectionsanyway TITLELINE COMMENTLINESAND ENDLINE TitleLineThetitlelinemustbethefirstintheinputfile Itscontentsareprintedverbatimastheheadingforeachsectionofoutput EndlineExamples ENDThe End linemustalwaysbethelastintheinputfile Notethattheperiodisanintegralpartofthename CommentsGeneralForm comment DEVICEMODELS Generalform MODELMNAMETYPE PNAME1 PVAL1PNAME2 PVAL2 Examples MODELMOD1NPN BF 50IS 1E 13VBF 50 Mostsimplecircuitelementstypicallyrequireonlyafewparametervalues However somedevices semiconductordevicesinparticular thatareincludedinSPICErequiremanyparametervalues Often manydevicesinacircuitaredefinedbythesamesetofdevicemodelparameters Forthesereasons asetofdevicemodelparametersisdefinedonaseparate MODELlineandassignedauniquemodelname ThedeviceelementlinesinSPICEthenrefertothemodelname DEVICEMODELS Forthesemorecomplexdevicetypes eachdeviceelementlinecontainsthedevicename thenodestowhichthedeviceisconnected andthedevicemodelname Inaddition otheroptionalparametersmaybespecifiedforsomedevices geometricfactorsandaninitialcondition seethefollowingsectiononTransistorsandDiodesformoredetails DEVICEMODELS MNAMEintheaboveisthemodelname andtypeisoneofthefollowingfifteentypes RSemiconductorresistormodelCSemiconductorcapacitormodelSWVoltagecontrolledswitchCSWCurrentcontrolledswitchURCUniformdistributedRCmodelLTRALossytransmissionlinemodel DEVICEMODELS DDiodemodelNPNNPNBJTmodelPNPPNPBJTmodelNJFN channelJFETmodelPJFP channelJFETmodelNMOSN channelMOSFETmodelPMOSP channelMOSFETmodelNMFN channelMESFETmodelPMFP channelMESFETmodel SUBCIRCUITS AsubcircuitthatconsistsofSPICEelementscanbedefinedandreferencedinafashionsimilartodevicemodels Thesubcircuitisdefinedintheinputfilebyagroupingofelementlines theprogramthenautomaticallyinsertsthegroupofelementswhereverthesubcircuitisreferenced Thereisnolimitonthesizeorcomplexityofsubcircuits andsubcircuitsmaycontainothersubcircuits Generalform SUBCKTsubnamN1N3 SUBCIRCUITS Acircuitdefinitionisbegunwitha SUBCKTline SUBNAMisthesubcircuitname andN1 N2 aretheexternalnodes whichcannotbezero Thegroupofelementlineswhichimmediatelyfollowthe SUBCKTlinedefinethesubcircuit Thelastlineinasubcircuitdefinitionisthe ENDSline seebelow Controllinesmaynotappearwithinasubcircuitdefinition however subcircuitdefinitionsmaycontainanythingelse includingothersubcircuitdefinitions devicemodels andsubcircuitcalls seebelow Notethatanydevicemodelsorsubcircuitdefinitionsincludedaspartofasubcircuitdefinitionarestrictlylocal i e suchmodelsanddefinitionsarenotknownoutsidethesubcircuitdefinition Also anyelementnodesnotincludedonthe SUBCKTlinearestrictlylocal withtheexceptionof0 ground whichisalwaysglobal COMBININGFILES INCLUDELINES Generalform INCLUDEfilenameExamples INCLUDE users spice common wattmeter cirFrequently portionsofcircuitdescriptionswillbereusedinseveralinputfiles particularlywithcommonmodelsandsubcircuits Inanyspiceinputfile the include linemaybeusedtocopysomeotherfileasifthatsecondfileappearedinplaceofthe include lineintheoriginalfile Thereisnorestrictiononthefilenameimposedbyspicebeyondthoseimposedbythelocaloperatingsystem Part4AnalysisandOutputControl SIMULATORVARIABLES OPTIONS VariousparametersofthesimulationsavailableinSpice3canbealteredtocontroltheaccuracy speed ordefaultvaluesforsomedevices Theseparametersmaybechangedviathe set command describedlaterinthesectionontheinteractivefront end orviathe OPTIONS line Generalform OPTIONSOPT1OPT2 orOPT OPTVAL INITIALCONDITIONS SpecifyInitialNodeVoltageGuessesGeneralform NODESETV NODNUM VALV NODNUM VAL Examples NODESETV 12 4 5V 4 2 23TheNodesetlinehelpstheprogramfindthedcorinitialtransientsolutionbymakingapreliminarypasswiththespecifiednodesheldtothegivenvoltages Therestrictionisthenreleasedandtheiterationcontinuestothetruesolution The NODESETlinemaybenecessaryforconvergenceonbistableora stablecircuits Ingeneral thislineshouldnotbenecessary INITIALCONDITIONS SetInitialConditionsGeneralform ICV NODNUM VALV NODNUM VAL Examples ICV 11 5V 4 5V 2 2 2TheIClineisforsettingtransientinitialconditions Ithastwodifferentinterpretations dependingonwhethertheUICparameterisspecifiedonthe TRANcontrolline Also oneshouldnotconfusethislinewiththe NODESETline The NODESETlineisonlytohelpdcconvergence anddoesnotaffectfinalbiassolution exceptformulti stablecircuits ANALYSIS Small SignalACAnalysisGeneralform ACDECNDFSTARTFSTOP ACOCTNOFSTARTFSTOP ACLINNPFSTARTFSTOPExamples ACDEC10110K ACDEC101K100MEG ACLIN1001100HZDECstandsfordecadevariation andNDisthenumberofpointsperdecade OCTstandsforoctavevariation andNOisthenumberofpointsperoctave LINstandsforlinearvariation andNPisthenumberofpoints FSTARTisthestartingfrequency andFSTOPisthefinalfrequency Ifthislineisincludedintheinputfile SPICEperformsanACanalysisofthecircuitoverthespecifiedfrequencyrange Notethatinorderforthisanalysistobemeaningful atleastoneindependentsourcemusthavebeenspecifiedwithanacvalue ANALYSIS DCTransferFunctionGeneralform DCSRCNAMVSTARTVSTOPVINCR SRC2START2STOP2INCR2 Examples DCVIN0 255 00 25 DCVDS010 5VGS051 DCVCE010 25IB010U1UTheDClinedefinesthedctransfercurvesourceandsweeplimits againwithcapacitorsopenandinductorsshorted SRCNAMisthenameofanindependentvoltageorcurrentsource VSTART VSTOP andVINCRarethestarting final andincrementingvaluesrespectively ThefirstexamplecausesthevalueofthevoltagesourceVINtobesweptfrom0 25Voltsto5 0Voltsinincrementsof0 25Volts Asecondsource SRC2 mayoptionallybespecifiedwithassociatedsweepparameters Inthiscase thefirstsourceissweptoveritsrangeforeachvalueofthesecondsource Thisoptioncanbeusefulforobtainingsemiconductordeviceoutputcharacteristics SeethesecondexamplecircuitdescriptioninAppendixA ANALYSIS DistortionAnalysisGeneralform DISTODECNDFSTARTFSTOP Examples DISTODEC101kHz100Mhz DISTODEC101kHz100Mhz0 9 ANALYSIS NoiseAnalysisGeneralform NOISEV OUTPUT SRC DEC LIN OCT PTSFSTARTFSTOP PER SUMMARY Examples NOISEV 5 VINDEC101kHZ100Mhz NOISEV 5 3 V1OCT81 01 0e61 ANALYSIS Pole ZeroAnalysisGeneralform PZNODE1NODE2NODE3NODE4CURPOL PZNODE1NODE2NODE3NODE4CURZER PZNODE1NODE2NODE3NODE4CURPZ PZNODE1NODE2NODE3NODE4VOLPOL PZNODE1NODE2NODE3NODE4VOLZER PZNODE1NODE2NODE3NODE4VOLPZExamples PZ1030CURPOL PZ2350VOLZER PZ4141CURPZ ANALYSIS DCorSmall SignalACSensitivityAnalysisGeneralform SENSOUTVAR SENSOUTVARACDECNDFSTARTFSTOP SENSOUTVARACOCTNOFSTARTFSTOP SENSOUTVARACLINNPFSTARTFSTOPExamples SENSV 1 OUT SENSV OUT ACDEC10100100k SENSI VTEST ANALYSIS TransferFunctionAnalysisGeneralform TFOUTVARINSRCExamples TFV 5 3 VIN TFI VLOAD VIN ANALYSIS TransientAnalysisGeneralform TRANTSTEPTSTOP Examples TRAN1NS100NS TRAN1NS1000NS500NS TRAN10NS1US BATCHOUTPUT SAVELinesGeneralform SAVEvectorvectorvector Examples SAVEi vin inputoutput SAVE m1 id Thevectorslistedonthe SAVElinearerecordedintherawfileforuselaterwithspice3ornutmeg nutmegisjustthedata analysishalfofspice3 withouttheabilitytosimulate Thestandardvectornamesareaccepted Ifno SAVElineisgiven thenthedefaultsetofvectorsaresaved nodevoltagesandvoltagesourcebranchcurrents If SAVElinesaregiven onlythosevectorsspecifiedaresaved BATCHOUTPUT PRINTLinesGeneralform PRINTPRTYPEOV1 OV8 Examples PRINTTRANV 4 I VIN PRINTDCV 2 I VSRC V 23 17 PRINTACVM 4 2 VR 7 VP 8 3 ThePrintlinedefinesthecontentsofatabularlistingofonetoeightoutputvariables PRTYPEisthetypeoftheanalysis DC AC TRAN NOISE orDISTO forwhichthespecifiedoutputsaredesired BATCHOUTPUT PLOTLinesGeneralform PLOTPLTYPEOV1 OV8 Examples PLOTDCV 4 V 5 V 1 PLOTTRANV 17 5 2 5 I VIN V 17 1 9 PLOTACVM 5 VM 31 24 VDB 5 VP 5 PLOTDISTOHD2HD3 R SIM2 PLOTTRANV 5 3 V 4 0 5 V 7 0 10 ThePlotlinedefinesthecontentsofoneplotoffromonetoeightoutputvariables PLTYPEisthetypeofanalysis DC AC TRAN NOISE orDISTO forwhichthespecifiedoutputsaredesired ThesyntaxfortheOVIisidenticaltothatforthe PRINTlineandfortheplotcommandintheinteractivemode BATCHOUTPUT FOUR FourierAnalysisofTransientAnalysisOutputGeneralform FOURFREQOV1OV3 Examples FOUR100KV 5 Part5CircuitElements ELEMENTARYDEVICES ResistorsGeneralform RXXXXXXXN1N2VALUEExamples R112100RC112171KN1andN2arethetwoelementnodes VALUEistheresistance inohms andmaybepositiveornegativebutnotzero SemiconductorResistorsGeneralform RXXXXXXXN1N2Examples RLOAD21010KRMOD37RMODELL 10uW 1u ELEMENTARYDEVICES CapacitorsGeneralform CXXXXXXXN N VALUEExamples CBYP1301UFCOSC172310UIC 3VN andN arethepositiveandnegativeelementnodes respectively VALUEisthecapacitanceinFarads SemiconductorCapacitorsGeneralform CXXXXXXXN1N2Examples CLOAD21010PCMOD37CMODELL 10uW 1u ELEMENTARYDEVICES InductorsGeneralform LYYYYYYYN N VALUEExamples LLINK42691UHLSHUNT235110UIC 15 7MAN andN arethepositiveandnegativeelementnodes respectively VALUEistheinductanceinHenries ELEMENTARYDEVICES Coupled Mutual InductorsGeneralform KXXXXXXXLYYYYYYYLZZZZZZZVALUEExamples K43LAALBB0 999KXFRMRL1L20 87LYYYYYYYandLZZZZZZZarethenamesofthetwocoupledinductors andVALUEisthecoefficientofcoupling K whichmustbegreaterthan0andlessthanorequalto1 Usingthe dot convention placea dot onthefirstnodeofeachinductor ELEMENTARYDEVICES SwitchesGeneralform SXXXXXXXN N NC NC MODELWYYYYYYYN N VNAMMODELExamples s11234switch1ONs25630sm2offSwitch112100smodel1w112vclockswitchmod1W230vrampsm1ONwreset56vclcklossyswitchOFF ELEMENTARYDEVICES IndependentSourcesGeneralform VXXXXXXXN N DC TRANVALUE IYYYYYYYN N DC TRANVALUE Examples VCC100DC6VIN1320 001AC1SIN 011MEG ISRC2321AC0 33345 0SFFM 0110K51K VMEAS129VCARRIER10DISTOF10 1 90 0VMODULATOR20DISTOF20 01IIN115AC1DISTOF1DISTOF20 001 ELEMENTARYDEVICES PulseGeneralform PULSE V1V2TDTRTFPWPER Examples VIN30PULSE 112NS2NS2NS50NS100NS ELEMENTARYDEVICES SinusoidalGeneralform SIN VOVAFREQTDTHETA Examples VIN30SIN 01100MEG1NS1E10 ELEMENTARYDEVICES ExponentialGeneralForm EXP V1V2TD1TAU1TD2TAU2 Examples VIN30EXP 4 12NS30NS60NS40NS ELEMENTARYDEVICES Piece WiseLinearGeneralForm PWL T1V1 Examples VCLOCK75PWL 0 710NS 711NS 317NS 318NS 750NS 7 ELEMENTARYDEVICES Single