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PrintedCircuitBoard(PCB)TestMethodologyUserGuideRevision1.6January2000OrderNumber:298179-001RPrintedCircuitBoard(PCB)TestMethodologyR2UserGuideInformationinthisdocumentisprovidedinconnectionwithIntelproducts.Nolicense,expressorimplied,byestoppelorotherwise,toanyintellectualpropertyrightsisgrantedbythisdocument.ExceptasprovidedinIntel’sTermsandConditionsofSaleforsuchproducts,Intelassumesnoliabilitywhatsoever,andInteldisclaimsanyexpressorimpliedwarranty,relatingtosaleand/oruseofIntelproductsincludingliabilityorwarrantiesrelatingtofitnessforaparticularpurpose,merchantability,orinfringementofanypatent,copyrightorotherintellectualpropertyright.Intelproductsarenotintendedforuseinmedical,lifesaving,orlifesustainingapplications.Intelmaymakechangestospecificationsandproductdescriptionsatanytime,withoutnotice.Designersmustnotrelyontheabsenceorcharacteristicsofanyfeaturesorinstructionsmarkedreservedorundefined.Intelreservestheseforfuturedefinitionandshallhavenoresponsibilitywhatsoeverforconflictsorincompatibilitiesarisingfromfuturechangestothem.ThePrintedCircuitBoard(PCB)TestMethodologymaycontaindesigndefectsorerrorsknownaserratawhichmaycausetheproducttodeviatefrompublishedspecifications.Currentcharacterizederrataareavailableonrequest.ContactyourlocalIntelsalesofficeoryourdistributortoobtainthelatestspecificationsandbeforeplacingyourproductorder.I2Cisa2-wirecommunicationsbus/protocoldevelopedbyPhilips.SMBusisasubsetoftheI2Cbus/protocolandwasdevelopedbyIntel.ImplementationsoftheI2Cbus/protocolmayrequirelicensesfromvariousentities,includingPhilipsElectronicsN.V.andNorthAmericanPhilipsCorporation.AlertonLANisaresultoftheIntel-IBMAdvancedManageabilityAllianceandatrademarkofIBMCopiesofdocumentswhichhaveanorderingnumberandarereferencedinthisdocument,orotherIntelliterature,maybeobtainedfrom:IntelCorporationwww.intel.comorcall1-800-548-4725*Third-partybrandsandnamesarethepropertyoftheirrespectiveowners.Copyright©IntelCorporation2000PrintedCircuitBoard(PCB)TestMethodologyRUserGuide3Contents1.Introduction...................................................................................................................................71.1.Overview..........................................................................................................................72.TestStructures.............................................................................................................................92.1.RequirementsforMatchingTestCoupontoBusDesign.................................................92.1.1.ImpedanceTestCouponGeneralGuidelines...................................................102.1.2.PropagationVelocityTestCouponGeneralGuidelines....................................103.ImpedanceandVelocityMeasurementTechniques...................................................................133.1.GeneralEquipment........................................................................................................133.2.GeneralCalibration........................................................................................................143.2.1.CalibrationSequence........................................................................................153.2.2.GeneralCalibrationVerification.........................................................................153.3.TDRDirectRambus(28Ω)ImpedanceCalibration.......................................................163.3.1.DirectRambusStandardExample.....................................................................173.3.2.Airline-28Ohm(Preferred)...............................................................................173.3.3.Airline-25Ohm.................................................................................................173.4.ProbingTechniques.......................................................................................................183.4.1.HandheldProbes...............................................................................................193.4.2.SMAConnectors...............................................................................................203.4.3.ControlledImpedanceMicroprobes..................................................................213.5.ImpedanceMeasurementTechniques..........................................................................233.5.1.DisplayAdjustment............................................................................................233.5.2.CursorPositioningMethod................................................................................243.5.3.AveragingMeanMethod(Preferred).................................................................243.5.4.FilterOption.......................................................................................................253.5.5.DifferentialImpedance......................................................................................263.6.VelocityMeasurementTechniques................................................................................273.6.1.