PCIExpress3.0TestingApproachesforPHYandProtocolLayersnametitle2010-4-262TektronixInnovationForum2010Agenda•IntroductiontoPCIExpress3.0–TrendsandChallenges•PhysicalLayerTestingOverview–TransmitterDesign&Validation–TransmitterCompliance–Receiver&SummaryofToolsforPCIePHYTesting•Protocol–Planningprobeaccess–Timetoconfidence–Informationdensity•Applications•Summary2010-4-263TektronixInnovationForum2010PCIExpress3.0TechnologyTimeline2009201020112112SiliconPhaseIntegrationPhase–ProductDevelopment–PCI-SIGToolDevelopmentDeploymentPhase0.71ReleaseToday0.5Release0.7Release–CEMSpecDevelopmentBaseSpecCEMSpec0.5Release0.7DraftTestSpec0.3ReleasePresentationContentbasedon.9BaseSpecificationDraftand.7CEMSpecificationDraftTektronixInvolvedinPCIeEWG,CEM,andSerialEnablingWorkingGroups2010-4-264TektronixInnovationForum2010PCIExpress3.0TrendsandImplications•Greatersystemcomplexityincreasestheengineeringchallenge•Higherdataratesignalshavelessmargin–requiresde-embedding•Crosstalk,skew,noiseandattenuationmoresignificant•LinktrainingandpowermanagementcontinuetobethemostdifficultchallengesImplications•Datatransferratescontinuetoincrease:2.558GT/s•128b/130bencoding•Backwardsinteroperability•Energyefficiency(LowermW/Gb/s)Industry/TechnologyTrends2010-4-265TektronixInnovationForum2010HighSpeedSerialTestChallengesDesignVerificationComplianceTestSimulationSignalIntegrityEyeandJitterAnalysisCharacterization&ValidationSystemIntegrationDigitalValidation&DebugSerialDataNetwork&LinkAnalysisDataLinkAnalysisDigitalvalidation&DebugComplianceTestingReceiverTestDirectSynthesisTransactionLayerDataLinkLayerPhysicalLayerLogicalSub-blockElectricalSub-blockpathTx+-+-+-+-RxCompleteValidation,Debug,ComplianceSolutions!!2010-4-266TektronixInnovationForum2010Agenda•IntroductiontoPCIExpress3.0–TrendsandChallenges•PhysicalLayerTestingOverview–TransmitterDesign&Validation–TransmitterCompliance–Receiver&SummaryofToolsforPCIePHYTesting•Protocol–Planningprobeaccess–Timetoconfidence–Informationdensity•Applications•Summary2010-4-26TektronixInnovationForum20107What’sNewforPCIExpressGen3.0Doublebandwidth(8GT/swith128b/130b)whileusingtraditionalcircuitboard(FR-4)Requiresde-embeddingmeasurementstoTxpins,specifiesbreakoutandreplicachannels.LargechannellossesrequireTxandRxequalization–Txequalization-Definedpre-shootandde-emphasisPresets–Rxequalization–behavioralCTLE&DFENewjitterseparationalgorithmsTransmitterDesign&ValidationPCIExpress2010-4-26TektronixInnovationForum20109PCIe3.0BaseSpecTransmitterVoltageandJitterMeasurementsBaseSpecMeasurementsdefinedatthepinsofthetransmitterNewJitterMeasurementsaredefinedforPCIe3.02010-4-26TektronixInnovationForum201010NewPCIe3.0JitterMeasurementsUncorrelatedTotalJitterandUncorrelatedDeterministicJitter–UncorrelatedjitterisnotmitigatedbyTxorRxequalizationandrepresentstimingmarginthatcannotberecoveredwithequalization.–DataDependentJitterisdeterminedbyaveragingfromarepeatedcompliancepattern–UncorrelatedJitterderivedafterremovingDataDependentJitter–ConstructthebathtubcurveinQscale–EstimateTotalJitterwithQScaleextrapolation2010-4-26TektronixInnovationForum201011NewPCIe3.0JitterMeasurements(cont’d)UncorrelatedTotalandDeterministicPWJ–Longlossychannelscausesinglepulsestobeattenuated–ISIcontributionsneedtoberemovedtodeterminePWJ–CalculatetheedgetoedgeJitter–ConstructthebathtubcurveinQscale–EstimateTotalJitterwithQScaleextrapolation2010-4-2612TektronixInnovationForum2010•TxmeasurementsreferencedtopinsbutcanonlyaccessTP1•Extractreplicachanneltransferfunction(S-Parameter)•AcquiresignalsatTP1thenmathematicallyremovechanneleffectsTransmitterCharacterizationTestChannel.s4p2010-4-26TektronixInnovationForum20101313De-embeddingRemovalofsignalimpairmentcausedbyselectedknownpartofthecircuit.Measurementsetupoftenknown–i.e.,afixture.Whenimpactsdoesthetestfixtureadd?WhatdoesthesignallooklikeattheTx,withoutthefixture?MeasuretheFixture(withTDR,VNA,etc)andandcapturethenetwork’sparameters(e.g.asaSparametertouchstonefile)►IntheoscilloscopeImporttheSparameterfile,viewthewaveformasitwasatthesource.+-+-FixtureMeasuredDe-embedded(calculatedinoscilloscopefrom‘Measure’andfromnetworkparametersoffixture)…closetothe‘True’True2010-4-2614TektronixInnovationForum2010ProbingandSignalAccess•TypicallyusedwhenasignalneedstobemeasuredandnoSMAorRFconnectorisavailable•Debug–Requireaquickwaytocheckthatsignalsarepresent–Soldertipscanbeusedforamorepermanentconnectionfortroubleshooting•ValidationandComplianceTesting–Chiptochipbuses2010-4-26TektronixInnovationForum201015Tektronix’SolutionsforPCIe3.0BaseSpecTestingTektronixDPOJETPCIe3.0SWAvailableTodayChannelEmbedding/De-embeddingsupportwith(SerialDataLinkAnalysis)SoftwareTXVoltageVTX-FS-NO-EQandVTX-RS-NO-EQMeasurementsavailabletodayinDPOJET20GhzReal-TimeOscilloscopeandProbesforFifthHarmonicCaptureTransmitterCompliancePCIExpress2010-4-26TektronixInnovationForum201017CEMSpecificationAdd-InCardTransmitterTestingTXmeasurementsbasedononepresetvalue(assumptionisthebestpresetwillbeusedforcompliance)MeasurementstakenafterRXEq