IPC7095.ppt

standardsandspecificationsthesevenwondersofdesigninnovation,introductiontoipcthepalletmayalsoincludecouponsfortesting.,hierarchyofipcdesignstandards(2220series),ipc-2222,rigid,ipc-2223,flex,ipc-2224,pcmcia,ipc-2225,mcm-l,ipc-2226,hdi,ipc-2221,generic,ipc-2220,hierarchyofprintedboardperformancestandards(6010series),ipc-6012,rigid,ipc-6013,flex,ipc-6014,pcmcia,ipc-6015,mcm-l,ipc-6016,hdi,ipc-6011,generic,ipc-6010,applicableipcstandards,-sm-782;landpatternconsiderations-7095;bgaprocessimplementation-2315;hdisolderflux/paste,scopeexample(landpatterns),thisstandardprovidesinformationonlandpatterngeometriesusedforsurfaceattachmentofelectroniccomponents.theintentoftheinformationpresentedistoprovidetheappropriatesize,shapeandtoleranceofsurfacemountlandpatternstoinsuresufficientareafortheappropriatesolderfilletorsoldervolume.alsotoallowforinspection,testing,andreworkofthosesolderjoints.,scope(continued),landpatterngeometrymaybedifferentbasedonthetypeofsolderingusedtoattachtheelectronicpart,howeverlandpatternsaredefinedinsuchamannerthattheyaretransparenttotheprocess.standardconfigurationsareformanualdesigns&forcomputer-aideddesign.partsaremountedononeorbothsides,subjectedtowave,reflow,orothertypeofsoldering,scope(continued),althoughpatternsaredimensionallydefinedandsincetheyareapartoftheprintedboardcircuitrygeometry,theyaresubjecttotheproducibilitylevelsandtolerancesassociatedwithplating,etching,assemblyorotherconditions.theproducibilityaspectsalsopertaintotheuseofsoldermaskandtheregistrationrequiredbetweenthesoldermaskandtheconductorpatterns.,performanceclasses,threeperformanceclasseshavebeenestablishedtoreflectprogressiveincreasesinsophistication,functionalperformancerequirementsandtesting/inspectionfrequency.theremaybeanoverlapofequipmentcategoriesindifferentclasses.theuserisresponsibletospecify,inthecontractorpurchaseorder,theproductperformanceclass.,class1-generalelectronicproducts,includesconsumerproducts,somecomputerandcomputerperipheralssuitableforapplicationswherecosmeticimperfectionsarenotimportantandthemajorrequirementisfunctionofthecompletedprintedboard.,class2-dedicatedserviceelectronicproducts,includescommunicationsequipment,sophisticatedbusinessmachines,instrumentswherehighperformanceandextendedlifeisrequiredandforwhichuninterruptedserviceisdesiredbutnotcritical.certaincosmeticimperfectionsareallowed.,class3-highreliabilityelectronicproducts,includestheequipmentandproductswherecontinuedperformanceorperformanceondemandiscritical.equipmentdowntimecannotbetoleratedandmustfunctionwhenrequiredsuchasinlifesupportitemsorflightcontrolsystems.applicationswherehighlevelsofassurancearerequiredandserviceisessential.,interpretation,“shall,”theemphaticformoftheverb,isusedthroughoutthisspecificationwheneverarequirementisintendedtoexpressaprovisionthatisbinding.deviationfroma“shall”requirementmaybeconsideredifsufficientdataissuppliedtojustifytheexception.thewords“should”and“may”areusedwheneveritisnecessarytoexpressnon-mandatoryprovisions.“will”isusedtoexpressadeclarationofpurpose.toassistthereader,theword“shall”ispresentedinboldcharacters.,complexitylevels,landpatterndeterminationmethods:exactdetailsbasedoncomponentspecifications,boardmanufacturingandcomponentplacementaccuracy.thelandpatternsarerestrictedtoaspecificcomponent,andhaveanidentifyinglandpatternnumberequationsusedfornewcomponentsortoalterthegiveninformationtoachieveamorerobustsolderconnection,whenusedinparticularsituations,levela:maximum,forlow-densityproductapplications,themaximumlandpatternconditionhavebeendevelopedtoaccommodatewaveorflowsolderofleadlesschipdevicesandleadedgull-wingdevices.thegeometryfurnishedforthesedevices,aswellasinwardand“j”-formedleadcontactdevicefamilies,mayprovideawiderprocesswindowforreflowsolderprocessesaswell.,levelb:median,productswithamoderatelevelofcomponentdensityshouldconsideradaptingthemedianlandpatterns.themedianlandpatternsfurnishedforalldevicefamilieswillprovidearobustsolderattachmentconditionforreflowsolderprocesses.theconditionshouldsuitableforwaveorreflowsolderingofleadlesschipandleadedgull-wingtypedevices.,levelc:minimum,highcomponentdensitytypicalofportableandhand-heldproductapplicationsmayconsidertheminimumlandpatterngeometryvariation.selectionoftheminimumlandpatterngeometrymaynotbesuitableforallproductusecategories.,combinationofissues,performanceclasses1,2,and3arecombinedwiththatofcomplexityanddensitylevelsa,b,andcindefiningelectronicassemblyconditions.asanexample,combiningthedescriptionaslevels1aor3bor2c,wouldindicatethedifferentcombinationsofperformanceandcomponentdensitytounderstandfabricationandassemblyrequirementsformanufacturingandenduseenvironment.,testrequirements,priortostartingadesign,atestabilityreviewmeetingshouldbeheldwithfabrication,assembly,andtesting.testabilityconcerns,suchascircuitvisibility,density,operation,circuitcontrollability,partitioning,andspecialtestrequirementsandspecificationsarediscussedasapartoftheteststrategy,testrequirements,duringthedesigntestabilityreviewmeeting,toolingconceptsareestablished,anddeterminationsaremadeastothemosteffectivetoolcostversusboardlayoutconceptconditions.duringthelayoutprocess,anycircuitboardchangesthatimpactthetestprogram,orthetesttooling,shouldbereportedtodeterminethebestcompromise.,boardtestrequirements,thetestingconceptshoulddevelopapproachesthatcanchecktheboardforproblems,andalsodetectfaultlocationswhereverpossible.thetestconceptandrequirementsshouldeconomicallyfacilitatethedetection,isolation,andcorrectionoffaultsofthedesignverification,manufacturing,andfieldsupportoftheprintedboardassemblylifecycle.,assemblytestability,theprintedboardassemblytestabilityphilosophyalsoneedstobecompatiblewiththeoverallintegration,testingandmaintenanceplans.thisincludes:thefactorytesterstobeusedhowintegrationandtestisplannedwhenconformalcoatedisapplieddepot&fieldtestequipmentcapabilitypersonnelskilllevel,needforautomation,standardsneededfordesignandassemblynewconceptsinbusinessprocessoptimizationforcompetitivenessaneedforloweroperatingcostsinbusinessandinformationtransfer(it).tightbusinessalignmentwithitisessentialdevelopmentofinternalandexternalserviceorientedarchitectureisneededinordertomanagethenewculturechange.shortenproductdevelopmentcyclesincreaseproductflexibilitysolutionsrequirecontinuousmonitoringofindustryprogress&infrastructuregrowth,ipctoiecdeployment,ipc-sm-782providedbyustoieccountriesagreetostandardizejapanfoundthatonelandpatternisinsufficienttodesignsonyminicamassembliesdiscussionsreviewprinciplesofmathematicalmodeltightenrequirementsthreegeometriesproposedforfutureiecstartsworkoniec-61188-5-1thru-8ipcsupersedessm-782awithipc-7351computermodeltestedwithpcblibraries,ipc-7351landpatternvariations,densitylevela:maximum(most)landprotrusion-forlowcomponentdensityapplicationsandproductsexposedtohighshockorvibration.thesolderpatternisthemostrobustandcanbeeasilyreworkedifnecessary.densitylevelb:median(nominal)landprotrusion-forproductswithamoderatelevelofcomponentdensityandprovidingamorerobustsolderattachment.densitylevelc:minimum(least)landprotrusion-forminiaturedeviceswherethelandpatternhastheleastamountofsolderpatterntoachievethehighestcomponentpackingdensity.,ipc-7351landpatternvariationsforrectangulartwoterminaldevices,densitylevelaveryrobustsolderjoint,densitylevelbgeneralpurposesolderjoint,densitylevelcminimalsolderjointforhighdensityapplications,ipc-7351landpatternvariationsforflatribbonlandgullwingleads,densitylevelaveryrobustsolderjoint,densitylevelbgeneralpurposesolderjoint,densitylevelcminimalsolderjointforhighdensityapplications,ribbonleadsgreaterthan0.625,ribbonleadslessthan0.625,jleadedparts,rectangularsquareendterminations,metalelectricalface,bottomonlyterminations,leadlesschipcarriers,inwardlshapedleads,flatlugleads,quadflatnolead,smalloutlinenolead,designconsiderations,landpatternconceptscomponentselectionmountingsubstratedesignassemblymethodsmethodoftestphototoolgenerationmeetingsolderjointrequirementsstencilfixturerequirementsprovidingaccessforinspectionaccessforreworkandrepair,manufacturingallowance,manufacturingallowancemustbeconsideredinthedesignprocessthecourtyardrepresentsthestartingpointoftheminimumareaneededforthecomponentandthelandpatternmanufacturing,assemblyandtestingrepresentativesshouldassistindeterminingtheadditionalroomneededtoaccommodateplacement,testing,modificationandrepair,ipc-7351landpatterncourtyarddetermination,ipc-7351landpatternnamingconvention,thenumberingconventionusedinipc-sm-782awasverybasicfixednumberrangeassignedtoaspecificcomponentfamily(pronetoexhaustion)nointelligenceembeddedwithinthemanewlandpatternnamingconventionwasdesignedforipc-7351toconveyanumberofattributes:componentfamilyprefixcomponentpinpitchcomponentbodydimensionscomponentpinquantitylandpatterngeometry,ipc-7351landpatternnamingconventionexample,usingan0.80mmpitchquadflatpackage(qfp),theipc-7351landpatternnamingconventionisasfollows:qfp80p+leadspanl1nominalxleadspanl2nominalpinqtywherethe+(plussign)standsfor“inadditionto”(nospacebetweentheprefixandthebodysize),thex(capitalletterx)isusedinsteadoftheword“by”toseparatetwonumberssuchasheightxwidth,the(dash)isusedtoseparatethepinquantity,andthesuffixletters“l”,“m”and“n”signifywhenthelandprotrusionisattheirminimum(least),maximum(most)ormedian(nominal)geometryvariation.,ipc-7351landpatternnamingconventionexample(contd),qfp80p+1720x2320-80ntherefore,theabovelandpatternnameconveysthefollowinginformation:thecomponentfamilyprefixofqfpthecomponentpinpitchof0.80mmthecomponentleadspannominalx=17.20mmfor“1720”thecomponentleadspannominaly=23.20mmfor“2320”thetotalcomponentpinquantityof80pinsdensitylevelb(nominal)landpatterngeometry,ipc-7351zerocomponentrotations,ipc-7351provideszerocomponentrotationsthataredefinedintermsofthestandardcadcomponentlibrarywithrespecttoagivenpcbdesignacknowledgesthatasinglelandpatternmaybeusedforthesamecomponentpartfromdifferentsuppliers,allofwhommayprovidedifferentorientationsfortapeorreeleliminatesscenarioswhereapcbdesignerlosestheabilitytoreferenceasinglelandpatternwhenthezerocomponentrotationisaccordingtothemethodthecomponentisdeliveredtotheassemblymachine,ipc-7351zerocomponentrotations,ipc-7351landpatternsoftwaresuite,partselection,nominallibrarysearch,componentdescriptions,landpatterns,landpatternsandcourtyards,densitylevela,densitylevelb,densitylevelc,landpatternsandcourtyards,densitylevela,densitylevelb,densitylevelc,ipc-7351landpatternviewer,sharewareprogramincludedwithipc-7351under“pcbtoolsandcaculators”portabilitydoesntrequireawebbrowserenhancedsearchingcapabilities1:1relationshipforcomponents/graphicseasilyupdatedthroughfreedownloadof.plibraryfilesandprogramrevisions,buildingonthestandards,ipcwebsiteandlistservswillprovidefeedbackpointfornewlandpatterngenerationdevelopingcadinterfacesincorporatingtheconceptsintooffspring(thechildofgencamandodb+)ipc-2581(iec61182-2)betatestingtostartendof2005manycadcamcompaniescommitted,ipc-2581betatesting,dataextractionfromcadcamstepandrepeatplusprocesstoleranceinclusiondesignfilereview(padstacks)versuslayereddataassemblyinform