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  <xsd:element abstract="true" id="pdfs_AnalyticsMember" name="AnalyticsMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="pdfs_BusinessCombinationRecognizedLiabilityAssumedAccountsPayableAndOtherCurrentLiabilities" name="BusinessCombinationRecognizedLiabilityAssumedAccountsPayableAndOtherCurrentLiabilities" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant"/>
  <xsd:element abstract="true" id="pdfs_CommonStockOutstandingMember" name="CommonStockOutstandingMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="pdfs_ContractWithCustomerLiabilityRevenueRecognizedIncludingOpeningBalance" name="ContractWithCustomerLiabilityRevenueRecognizedIncludingOpeningBalance" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_CustomerAMember" name="CustomerAMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_CustomerBMember" name="CustomerBMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_CustomerCMember" name="CustomerCMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="pdfs_DebtInstrumentCovenantNetLeverageRatio" name="DebtInstrumentCovenantNetLeverageRatio" nillable="true" substitutionGroup="xbrli:item" type="xbrli:pureItemType" xbrli:periodType="instant"/>
  <xsd:element id="pdfs_DeferredIncomeTaxExpenseBenefitIncludingCumulativeTranslationAdjustment" name="DeferredIncomeTaxExpenseBenefitIncludingCumulativeTranslationAdjustment" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_DirectscanSystemAssetsMember" name="DirectscanSystemAssetsMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_DocumentAndEntityInformation" name="DocumentAndEntityInformation" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_EmployeeStockPurchasePlanMember" name="EmployeeStockPurchasePlanMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="pdfs_FixedChargeCoverageRatio" name="FixedChargeCoverageRatio" nillable="true" substitutionGroup="xbrli:item" type="xbrli:pureItemType" xbrli:periodType="instant"/>
  <xsd:element id="pdfs_IncreaseDecreaseInContractLiability" name="IncreaseDecreaseInContractLiability" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element id="pdfs_IncreaseDecreaseInOperatingLeaseRightOfUseAssets" name="IncreaseDecreaseInOperatingLeaseRightOfUseAssets" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element id="pdfs_IntangibleAssetFinitelivedEstimatedAmortizationExpenseAfterYearFour" name="IntangibleAssetFinitelivedEstimatedAmortizationExpenseAfterYearFour" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant"/>
  <xsd:element abstract="true" id="pdfs_IntegratedYieldRampMember" name="IntegratedYieldRampMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_LaboratoryAndTestEquipmentMember" name="LaboratoryAndTestEquipmentMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="pdfs_LineOfCreditFacilityUnusedCapacityCommitmentFeePercentageEbitdaRatioGreaterThan250To100" name="LineOfCreditFacilityUnusedCapacityCommitmentFeePercentageEbitdaRatioGreaterThan250To100" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:percentItemType" xbrli:periodType="duration"/>
  <xsd:element id="pdfs_LineOfCreditFacilityUnusedCapacityCommitmentFeePercentageEbitdaRatioLessThan050To100" name="LineOfCreditFacilityUnusedCapacityCommitmentFeePercentageEbitdaRatioLessThan050To100" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:percentItemType" xbrli:periodType="duration"/>
  <xsd:element id="pdfs_LineOfCreditFacilityUnusedCapacityCommitmentFeePercentageEbitdaRatioLessThan250To100ButGreaterThan050To100" name="LineOfCreditFacilityUnusedCapacityCommitmentFeePercentageEbitdaRatioLessThan250To100ButGreaterThan050To100" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:percentItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_NoteToFinancialStatementDetailsTextual" name="NoteToFinancialStatementDetailsTextual" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_NotesToFinancialStatements" name="NotesToFinancialStatements" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_NotesToFinancialStatementsAbstract" name="NotesToFinancialStatementsAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_OtherGeographicalAreasMember" name="OtherGeographicalAreasMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="pdfs_PercentageOfRevenue" name="PercentageOfRevenue" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:percentItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_PlatformMember" name="PlatformMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_PolicyTable" name="PolicyTable" nillable="true" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element id="pdfs_PrepaymentToAcquirePropertyPlantAndEquipment" name="PrepaymentToAcquirePropertyPlantAndEquipment" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_PropertyPlantAndEquipmentInProgressCvAndOtherAssetsMember" name="PropertyPlantAndEquipmentInProgressCvAndOtherAssetsMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="pdfs_ReceivablesByMajorCustomersTableTextBlock" name="ReceivablesByMajorCustomersTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType" xbrli:periodType="duration"/>
  <xsd:element id="pdfs_ReclassificationOfRevenueTableTextBlock" name="ReclassificationOfRevenueTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_RevolvingCreditFacilityFirstAmendmentMember" name="RevolvingCreditFacilityFirstAmendmentMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="pdfs_SalestypeAndDirectFinancingLeasesPaymentToBeReceivedAfterYearThree" name="SalestypeAndDirectFinancingLeasesPaymentToBeReceivedAfterYearThree" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant"/>
  <xsd:element abstract="true" id="pdfs_SecureWiseBusinessMember" name="SecureWiseBusinessMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="pdfs_SharebasedPaymentArrangementExpenseCostOfRevenues" name="SharebasedPaymentArrangementExpenseCostOfRevenues" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element id="pdfs_SharebasedPaymentArrangementExpenseResearchAndDevelopment" name="SharebasedPaymentArrangementExpenseResearchAndDevelopment" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element id="pdfs_SharebasedPaymentArrangementExpenseSellingGeneralAndAdministrative" name="SharebasedPaymentArrangementExpenseSellingGeneralAndAdministrative" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element id="pdfs_ShorttermAndVariableLeaseCost" name="ShorttermAndVariableLeaseCost" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_SoftwareLicenseAndRelatedServicesAgreementMember" name="SoftwareLicenseAndRelatedServicesAgreementMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_StrategicPartnershipMember" name="StrategicPartnershipMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_TermLoanMember" name="TermLoanMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_TestEquipmentMember" name="TestEquipmentMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_The2011PlanMember" name="The2011PlanMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_The2021PurchasePlanMember" name="The2021PurchasePlanMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_The2024ProgramMember" name="The2024ProgramMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_The2026ProgramMember" name="The2026ProgramMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_TheCreditFacilitiesMember" name="TheCreditFacilitiesMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="pdfs_TransferFromPrepaidAssetsToPropertyAndEquipment" name="TransferFromPrepaidAssetsToPropertyAndEquipment" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element id="pdfs_UnrecognizedTaxBenefitsInDeferredTaxAssets" name="UnrecognizedTaxBenefitsInDeferredTaxAssets" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant"/>
  <xsd:element abstract="true" id="pdfs_VolumebasedMember" name="VolumebasedMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_statement-statement-note-1-basis-of-presentation-and-summary-of-significant-accounting-policies-summary-of-reclassified-amounts-details" name="statement-statement-note-1-basis-of-presentation-and-summary-of-significant-accounting-policies-summary-of-reclassified-amounts-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_statement-statement-note-1-basis-of-presentation-and-summary-of-significant-accounting-policies-tables" name="statement-statement-note-1-basis-of-presentation-and-summary-of-significant-accounting-policies-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_statement-statement-note-10-customer-and-geographic-information-longlived-assets-by-geographic-area-details" name="statement-statement-note-10-customer-and-geographic-information-longlived-assets-by-geographic-area-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_statement-statement-note-10-customer-and-geographic-information-receivables-percentage-by-major-customers-details" name="statement-statement-note-10-customer-and-geographic-information-receivables-percentage-by-major-customers-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_statement-statement-note-10-customer-and-geographic-information-revenue-percentage-by-major-customers-details" name="statement-statement-note-10-customer-and-geographic-information-revenue-percentage-by-major-customers-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_statement-statement-note-10-customer-and-geographic-information-schedule-of-segment-reporting-information-details" name="statement-statement-note-10-customer-and-geographic-information-schedule-of-segment-reporting-information-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_statement-statement-note-10-customer-and-geographic-information-tables" name="statement-statement-note-10-customer-and-geographic-information-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_statement-statement-note-11-fair-value-measurement-schedule-of-financial-assets-details" name="statement-statement-note-11-fair-value-measurement-schedule-of-financial-assets-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_statement-statement-note-11-fair-value-measurements-tables" name="statement-statement-note-11-fair-value-measurements-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_statement-statement-note-14-business-combination-schedule-of-recognized-asset-acquired-and-liability-details" name="statement-statement-note-14-business-combination-schedule-of-recognized-asset-acquired-and-liability-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_statement-statement-note-14-business-combination-tables" name="statement-statement-note-14-business-combination-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_statement-statement-note-2-revenue-from-contracts-with-customers-revenue-by-geographic-area-details" name="statement-statement-note-2-revenue-from-contracts-with-customers-revenue-by-geographic-area-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_statement-statement-note-2-revenue-from-contracts-with-customers-schedule-of-capitalized-costs-details" name="statement-statement-note-2-revenue-from-contracts-with-customers-schedule-of-capitalized-costs-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_statement-statement-note-2-revenue-from-contracts-with-customers-schedule-of-contract-balances-details" name="statement-statement-note-2-revenue-from-contracts-with-customers-schedule-of-contract-balances-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_statement-statement-note-2-revenue-from-contracts-with-customers-schedule-of-disaggregation-of-revenue-details" name="statement-statement-note-2-revenue-from-contracts-with-customers-schedule-of-disaggregation-of-revenue-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_statement-statement-note-2-revenue-from-contracts-with-customers-tables" name="statement-statement-note-2-revenue-from-contracts-with-customers-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_statement-statement-note-3-balance-sheet-components-amortization-of-identifiable-intangible-assets-details" name="statement-statement-note-3-balance-sheet-components-amortization-of-identifiable-intangible-assets-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_statement-statement-note-3-balance-sheet-components-schedule-of-accrued-and-other-current-liabilities-details" name="statement-statement-note-3-balance-sheet-components-schedule-of-accrued-and-other-current-liabilities-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_statement-statement-note-3-balance-sheet-components-schedule-of-amortization-expense-details" name="statement-statement-note-3-balance-sheet-components-schedule-of-amortization-expense-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_statement-statement-note-3-balance-sheet-components-schedule-of-changes-in-goodwill-details" name="statement-statement-note-3-balance-sheet-components-schedule-of-changes-in-goodwill-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_statement-statement-note-3-balance-sheet-components-schedule-of-intangible-assets-net-details" name="statement-statement-note-3-balance-sheet-components-schedule-of-intangible-assets-net-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_statement-statement-note-3-balance-sheet-components-schedule-of-maturity-for-salestype-leases-details" name="statement-statement-note-3-balance-sheet-components-schedule-of-maturity-for-salestype-leases-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_statement-statement-note-3-balance-sheet-components-schedule-of-net-investments-in-salestype-leases-details" name="statement-statement-note-3-balance-sheet-components-schedule-of-net-investments-in-salestype-leases-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_statement-statement-note-3-balance-sheet-components-schedule-of-other-noncurrent-assets-details" name="statement-statement-note-3-balance-sheet-components-schedule-of-other-noncurrent-assets-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_statement-statement-note-3-balance-sheet-components-schedule-of-prepaid-expenses-and-other-current-assets-details" name="statement-statement-note-3-balance-sheet-components-schedule-of-prepaid-expenses-and-other-current-assets-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_statement-statement-note-3-balance-sheet-components-schedule-of-property-and-equipment-details" name="statement-statement-note-3-balance-sheet-components-schedule-of-property-and-equipment-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_statement-statement-note-3-balance-sheet-components-tables" name="statement-statement-note-3-balance-sheet-components-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_statement-statement-note-4-leases-lease-cost-details" name="statement-statement-note-4-leases-lease-cost-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_statement-statement-note-4-leases-maturity-of-operating-lease-liabilities-details" name="statement-statement-note-4-leases-maturity-of-operating-lease-liabilities-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_statement-statement-note-4-leases-tables" name="statement-statement-note-4-leases-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_statement-statement-note-5-debt-schedule-of-debt-instruments-details" name="statement-statement-note-5-debt-schedule-of-debt-instruments-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_statement-statement-note-5-debt-schedule-of-maturity-details" name="statement-statement-note-5-debt-schedule-of-maturity-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_statement-statement-note-5-debt-tables" name="statement-statement-note-5-debt-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_statement-statement-note-7-employee-benefit-plans-allocation-of-recognized-period-costs-details" name="statement-statement-note-7-employee-benefit-plans-allocation-of-recognized-period-costs-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_statement-statement-note-7-employee-benefit-plans-schedule-of-nonvested-restricted-stock-units-activity-details" name="statement-statement-note-7-employee-benefit-plans-schedule-of-nonvested-restricted-stock-units-activity-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_statement-statement-note-7-employee-benefit-plans-schedule-of-restricted-stock-unit-fair-value-details" name="statement-statement-note-7-employee-benefit-plans-schedule-of-restricted-stock-unit-fair-value-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_statement-statement-note-7-employee-benefit-plans-schedule-of-valuation-assumptions-details" name="statement-statement-note-7-employee-benefit-plans-schedule-of-valuation-assumptions-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_statement-statement-note-7-employee-benefit-plans-tables" name="statement-statement-note-7-employee-benefit-plans-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_statement-statement-note-9-net-income-loss-per-share-antidilutive-securities-details" name="statement-statement-note-9-net-income-loss-per-share-antidilutive-securities-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_statement-statement-note-9-net-income-loss-per-share-calculation-of-earnings-per-share-details" name="statement-statement-note-9-net-income-loss-per-share-calculation-of-earnings-per-share-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_statement-statement-note-9-net-income-loss-per-share-tables" name="statement-statement-note-9-net-income-loss-per-share-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="pdfs_statement-statement-significant-accounting-policies-policies" name="statement-statement-significant-accounting-policies-policies" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
</xsd:schema>
