Traditionally,electronICdesignautomation(EDA)hasbeenassociatedwithICdesign.Thefirsttoolswerefortransistor-levelsimulation;theyevolvedatCalBerkeleytobecomeSpice.Thenextclassoftoolswerethecomputer-aideddesign(CAD)toolsthathelpeddesignersinterconnecttheindividualdevices.Becausetheseweretheonlytoolsavailable,CADandEDAbecamesynonymouswiththeICdesignprocess.

ThisgroupingofallEDAasICdesigncontinuestoday.Therearemorethan150ICdesign,verificationandanalysistoolsinsomecompanies,andthebulkoftheEDArevenuescomefromtheICdesignsector.Althoughsomeaddtheadditionalcategoryofcomputeraidedmanufacturing(CAM),thatismorerelatedtotheactualmanufacturingfunctionsofrunningafactory.

TheproblemwiththisnarrowdefinitionofEDAisthatitexcludessomesignificantcategoriesoftools.ElectronicsystemsincludemanycomponentsbesidesICs-thereareprinted-circuitboards,packaging,wiringandevensoftware.Totakethecollectionofcomponentsbeyondtheconditionofaboxfullofparts,themanufacturingsidemustperformmanyassemblyandtestoperationsaswellastestandanalyzereliabilityandqualityassurance.

Assystemsmovethroughthecontinuumofprocessesofdesignandmanufacturing,oneoftheimportantfunctionsisthedesignformanufacturability(DFM)assessment、IntheICdesignphase,thisreviewoccursafterphysicaldesignintheparasiticextractionandanalysistools.TheanalysismaymisssomeimportantfactorsbecausetheICdesignprocessisfragmentedintofacetsofconsiderationliketiming,power,noiseandreliability.Thepointtoolsthatlookatthevariousfunctionsworkinrelativeisolation.

Atthepc-boardlevel,theDFManalysisconsidersphysicalandelectricalparameterslikedimensions,noiseandcrosstalk,anddeviceplacementandplacementorder.Thisanalysisphasestartstoletthemanufacturingconsiderationslikevendorqualityanddeliverycapabilitiesintrudeintothereview.Apcboardmighthaveaprobleminmanufacturingatonevendor,orsomeselectedcomponentsmayhaveunusualdeliveryorqualityconstraints.Theseconstraintsneedtobeaddressedasearlyinthedesigncycleaspossibletoavoidproblemsinthefirstsystemdeliveries.

Anotherareawheremanufacturingconcernsenteristest.EventhoughalargemajorityofICdesignersclaimtoconsiderdesignfortest(DFT)asapartofthedesignfunction,mostsystemsdonotgetanythingmorethancomponent-leveltestingprovidedaspartofthedesign-to-manufacturinghandoff.Thepaucityofsystem-leveltestfunctionsmeansthatthemanufacturingengineershavethesametypeofproblemthattheICdesignershaveinincorporatingsystem-levelfunctionblocksintothedesign.Thefunctionblockmayhavetestvectors,buttheoperatingenvironmentisdifferentbecausethepartisnolongerisolated.

Thetransitionfromdesign,to(virtual)prototype,tofinalproductrequiresawidevarietyofengineeringdisciplinesanddevelopmenttools.Whenengineersintegrateentiresystemsontoafewpiecesofsilicon,thedivisionsamongthevariousdevelopmentteams-hardware,software,testandmanufacturing-becomeblurred.Formerlyeasyorarbitrarydecisionsatthedesignlevelnowhaveadverseconsequencesinotherareasiftheteamsdon"tworkcloselytogetherthroughoutthedesigncycle.

AninclusiveviewofEDAwilllookatallareasofelectronicdesignwheretheapplicationofcomputer-basedtoolsassiststheengineerindevelopingaproduct.TheICdesignprocessisonlypartofthewholesetoffunctionsthatneedsandusescomputer-aideddesigntools.Withoutanintegratedviewoftheentiredesignchainfrominitialconceptsandspecificationstodeliveryofsystems,theproductionofthenext-generationsystemswillbecomeanexerciseinfutility.

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