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  <xs:element id="tndm_CashEquivalentsMaturityTerm" abstract="false" name="CashEquivalentsMaturityTerm" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="tndm_ConvertibleSeniorNotesDue2029Member" abstract="true" name="ConvertibleSeniorNotesDue2029Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="tndm_ConvertibleSeniorNotesDue2025Member" abstract="true" name="ConvertibleSeniorNotesDue2025Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="tndm_ConvertibleSeniorNotesMember" abstract="true" name="ConvertibleSeniorNotesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="tndm_HeadquartersLeaseMember" abstract="true" name="HeadquartersLeaseMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="tndm_HeadquartersLeasePhaseIMember" abstract="true" name="HeadquartersLeasePhaseIMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="tndm_HeadquartersLeasePhaseIIMember" abstract="true" name="HeadquartersLeasePhaseIIMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="tndm_VistaSorrentoLeaseMember" abstract="true" name="VistaSorrentoLeaseMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="tndm_LesseeOperatingLeaseNumberOfExtensions" abstract="false" name="LesseeOperatingLeaseNumberOfExtensions" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="tndm_LesseeOperatingLeaseLiabilityToBePaidYearsOneThroughFour" abstract="false" name="LesseeOperatingLeaseLiabilityToBePaidYearsOneThroughFour" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="tndm_GainLossOnTerminationOfLeaseAndOperatingLeaseImpairmentLoss" abstract="false" name="GainLossOnTerminationOfLeaseAndOperatingLeaseImpairmentLoss" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="tndm_OperatingLeaseTerminationPayments" abstract="false" name="OperatingLeaseTerminationPayments" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="tndm_OperatingLeaseCashPayments" abstract="false" name="OperatingLeaseCashPayments" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="tndm_ConversionInstance130Member" abstract="true" name="ConversionInstance130Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="tndm_ConversionInstance98Member" abstract="true" name="ConversionInstance98Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="tndm_CapillaryBiomedicalMember" abstract="true" name="CapillaryBiomedicalMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="tndm_PaymentsForCappedCalls" abstract="false" name="PaymentsForCappedCalls" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="tndm_DebtInstrumentAdditionalInterestRatePercentage" abstract="false" name="DebtInstrumentAdditionalInterestRatePercentage" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="tndm_InterestExpenseDebtAdditionalAmount" abstract="false" name="InterestExpenseDebtAdditionalAmount" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="tndm_DebtInstrumentCappedCallNetCost" abstract="false" name="DebtInstrumentCappedCallNetCost" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="tndm_OptionIndexedToIssuersEquityCapPrice" abstract="false" name="OptionIndexedToIssuersEquityCapPrice" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:perShareItemType"/>
  <xs:element id="tndm_ProceedsFromCappedCallTermination" abstract="false" name="ProceedsFromCappedCallTermination" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="tndm_AssetAcquisitionLiabilitiesLongTermDebtAssumed" abstract="false" name="AssetAcquisitionLiabilitiesLongTermDebtAssumed" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="tndm_StockOptionsIssuedAndOutstandingMember" abstract="true" name="StockOptionsIssuedAndOutstandingMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="tndm_AuthorizedForFutureOptionGrantsMember" abstract="true" name="AuthorizedForFutureOptionGrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="tndm_CommonStockWarrantExpiringMarch2027Member" abstract="true" name="CommonStockWarrantExpiringMarch2027Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="tndm_DateOfOfferingMember" abstract="true" name="DateOfOfferingMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="tndm_DateOfPurchaseMember" abstract="true" name="DateOfPurchaseMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="tndm_PerformanceBasedRestrictedStockUnitsMember" abstract="true" name="PerformanceBasedRestrictedStockUnitsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="tndm_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardRemainingVestingPeriod" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardRemainingVestingPeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="tndm_OfferingPeriod" abstract="false" name="OfferingPeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="tndm_NumberOfPurchasePeriods" abstract="false" name="NumberOfPurchasePeriods" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="tndm_PurchasePeriod" abstract="false" name="PurchasePeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="tndm_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriodAggregateIntrinsicValue" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriodAggregateIntrinsicValue" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="tndm_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedExpectedToVestNumber" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedExpectedToVestNumber" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="tndm_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedExpectedToVestWeightedAverageGrantDateFairValue" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedExpectedToVestWeightedAverageGrantDateFairValue" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types1:perShareItemType"/>
  <xs:element id="tndm_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedExpectedToVestAggregateIntrinsicValue" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedExpectedToVestAggregateIntrinsicValue" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="tndm_DefinedContributionPlanMinimumAgeOfEmployee" abstract="false" name="DefinedContributionPlanMinimumAgeOfEmployee" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="tndm_EffectiveIncomeTaxRateReconciliationConvertibleDebtLegOutAmount" abstract="false" name="EffectiveIncomeTaxRateReconciliationConvertibleDebtLegOutAmount" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="tndm_IncomeTaxReconciliationWarrantsRevaluation" abstract="false" name="IncomeTaxReconciliationWarrantsRevaluation" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="tndm_EffectiveIncomeTaxRateReconciliationNetOperatingLossCarryforward" abstract="false" name="EffectiveIncomeTaxRateReconciliationNetOperatingLossCarryforward" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="tndm_EffectiveIncomeTaxRateReconciliationOfficersCompensation" abstract="false" name="EffectiveIncomeTaxRateReconciliationOfficersCompensation" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="tndm_EffectiveIncomeTaxRateReconciliationDeferredTaxAssetsAcquired" abstract="false" name="EffectiveIncomeTaxRateReconciliationDeferredTaxAssetsAcquired" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="tndm_OperatingLossCarryforwardNotSubjectToExpiration" abstract="false" name="OperatingLossCarryforwardNotSubjectToExpiration" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="tndm_OperatingLossCarryforwardsSubjectToExpiration" abstract="false" name="OperatingLossCarryforwardsSubjectToExpiration" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="tndm_AssetAcquisitionDeferredTaxAssetsAcquired" abstract="false" name="AssetAcquisitionDeferredTaxAssetsAcquired" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="tndm_IncomeTaxExaminationRealizationPercent" abstract="false" name="IncomeTaxExaminationRealizationPercent" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:percentItemType"/>
  <xs:element id="tndm_DeferredTaxAssetsLeaseLiabilities" abstract="false" name="DeferredTaxAssetsLeaseLiabilities" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="tndm_NumberOfGeographicalMarkets" abstract="false" name="NumberOfGeographicalMarkets" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="tndm_PumpMember" abstract="true" name="PumpMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="tndm_SuppliesAndOtherMember" abstract="true" name="SuppliesAndOtherMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="tndm_TandemChoiceProgramRecognizedDeferredMember" abstract="true" name="TandemChoiceProgramRecognizedDeferredMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="tndm_AMFMedicalAcquisitionMember" abstract="true" name="AMFMedicalAcquisitionMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="tndm_DevelopmentMilestonesMember" abstract="true" name="DevelopmentMilestonesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="tndm_RegulatoryClearanceMilestoneMember" abstract="true" name="RegulatoryClearanceMilestoneMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="tndm_AssetAcquisitionContingentConsiderationArrangementsRangeOfOutcomesValueHigh" abstract="false" name="AssetAcquisitionContingentConsiderationArrangementsRangeOfOutcomesValueHigh" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="tndm_AssetAcquisitionMilestonePeriod" abstract="false" name="AssetAcquisitionMilestonePeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="tndm_TandemChoiceProgramMember" abstract="true" name="TandemChoiceProgramMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
</xs:schema>
