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  <xs:element id="tndm_OptionIndexedToIssuersEquityCapPrice" abstract="false" name="OptionIndexedToIssuersEquityCapPrice" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType"/>
  <xs:element id="tndm_ScheduleOfCommonStockReservedForFutureIssuanceTableTextBlock" abstract="false" name="ScheduleOfCommonStockReservedForFutureIssuanceTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="tndm_TechCenterLeasePhaseIMember" abstract="true" name="TechCenterLeasePhaseIMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="tndm_WarrantLiabilitiesPolicyTextBlock" abstract="false" name="WarrantLiabilitiesPolicyTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="tndm_LesseeOperatingLeaseAnnualIncreaseInMonthlyBaseRentPercentage" abstract="false" name="LesseeOperatingLeaseAnnualIncreaseInMonthlyBaseRentPercentage" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="tndm_VistaSorrentoParkwayLeaseMember" abstract="true" name="VistaSorrentoParkwayLeaseMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <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_CashCashEquivalentsAndShortTermInvestmentsLineItems" abstract="true" name="CashCashEquivalentsAndShortTermInvestmentsLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="tndm_DateOfPurchaseMember" abstract="true" name="DateOfPurchaseMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="tndm_CustomerCMember" abstract="true" name="CustomerCMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="tndm_SlimCartridgesAndInfusionSetsMember" abstract="true" name="SlimCartridgesAndInfusionSetsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="tndm_PaymentsForCappedCallTransactions" abstract="false" name="PaymentsForCappedCallTransactions" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="tndm_ShorelineDriveBoiseIdahoMember" abstract="true" name="ShorelineDriveBoiseIdahoMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <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_DefinedContributionPlanMinimumAgeOfEmployee" abstract="false" name="DefinedContributionPlanMinimumAgeOfEmployee" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="tndm_CashCashEquivalentsAndShortTermInvestmentsTable" abstract="true" name="CashCashEquivalentsAndShortTermInvestmentsTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="tndm_CustomerAMember" abstract="true" name="CustomerAMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="tndm_HighBluffDriveLeaseMember" abstract="true" name="HighBluffDriveLeaseMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="tndm_TechCenterLeaseMember" abstract="true" name="TechCenterLeaseMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="tndm_SummaryOfSignificantAccountingPoliciesTable" abstract="true" name="SummaryOfSignificantAccountingPoliciesTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="tndm_ConvertibleSeniorNotesMember" abstract="true" name="ConvertibleSeniorNotesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="tndm_LossContingencyNumberOfPlaintiffsToDismissed" abstract="false" name="LossContingencyNumberOfPlaintiffsToDismissed" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="tndm_TwoThousandThirteenStockIncentivePlanMember" abstract="true" name="TwoThousandThirteenStockIncentivePlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="tndm_CommonStockWarrantExpiringBetweenMarch2022AndAugust2022Member" abstract="true" name="CommonStockWarrantExpiringBetweenMarch2022AndAugust2022Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="tndm_NatureOfOperationPolicyTextBlock" abstract="false" name="NatureOfOperationPolicyTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="tndm_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardRemainingVestingPeriod" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardRemainingVestingPeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="tndm_CommonStockWarrants" abstract="false" name="CommonStockWarrants" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="tndm_FairValueOfCommonStockWarrantsAtTimeOfExercise" abstract="false" name="FairValueOfCommonStockWarrantsAtTimeOfExercise" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="tndm_ProductsWarrantyPeriod" abstract="false" name="ProductsWarrantyPeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="tndm_CommonStockWarrantExpiringOctober2022Member" abstract="true" name="CommonStockWarrantExpiringOctober2022Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="tndm_InvestmentOwnedOwnershipInterest" abstract="false" name="InvestmentOwnedOwnershipInterest" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="tndm_PaymentsToAcquireIntangibleAssetsAndEquityInvestments" abstract="false" name="PaymentsToAcquireIntangibleAssetsAndEquityInvestments" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="tndm_LesseeOperatingLeaseMonthlyIncreaseInBaseRent" abstract="false" name="LesseeOperatingLeaseMonthlyIncreaseInBaseRent" 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_SummaryOfSignificantAccountingPoliciesLineItems" abstract="true" name="SummaryOfSignificantAccountingPoliciesLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="tndm_PhaseAxis" abstract="true" name="PhaseAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="tndm_OrganizationAndBasisOfPresentationLineItems" abstract="true" name="OrganizationAndBasisOfPresentationLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="tndm_RoselleStreetSanDiegoCaliforniaMember" abstract="true" name="RoselleStreetSanDiegoCaliforniaMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="tndm_DebtInstrumentRemainingTerm" abstract="false" name="DebtInstrumentRemainingTerm" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="tndm_PhaseDomain" abstract="true" name="PhaseDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="tndm_NumberOfPurchasePeriods" abstract="false" name="NumberOfPurchasePeriods" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="tndm_SupranationalBondsMember" abstract="true" name="SupranationalBondsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <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_IncomeTaxDisclosureLineItems" abstract="true" name="IncomeTaxDisclosureLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="tndm_AuditInformationAbstract" abstract="true" name="AuditInformationAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="tndm_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriodAggregateIntrinsicValue" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriodAggregateIntrinsicValue" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
</xs:schema>
