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  <xs:element id="tndm_CashCashEquivalentsAndShortTermInvestmentsLineItems" abstract="true" name="CashCashEquivalentsAndShortTermInvestmentsLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="tndm_DateOfOfferingMember" abstract="true" name="DateOfOfferingMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum: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_OrganizationAndBasisOfPresentationTable" abstract="true" name="OrganizationAndBasisOfPresentationTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="tndm_ContingentEmployeeStockOptionsMember" abstract="true" name="ContingentEmployeeStockOptionsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum: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_AdjustmentsToAdditionalPaidInCapitalShareBasedCompensationRequisiteServicePeriodRecognitionShares" abstract="false" name="AdjustmentsToAdditionalPaidInCapitalShareBasedCompensationRequisiteServicePeriodRecognitionShares" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="tndm_ProceedsFromPublicOfferingNetOfOfferingCosts" abstract="false" name="ProceedsFromPublicOfferingNetOfOfferingCosts" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="tndm_ProductLifeSpanTerm" abstract="false" name="ProductLifeSpanTerm" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <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_StockIssuedDuringPeriodValueCommonStockWarrantsExercised" abstract="false" name="StockIssuedDuringPeriodValueCommonStockWarrantsExercised" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="tndm_CustomerBMember" abstract="true" name="CustomerBMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="tndm_AuthorizedForFutureOptionGrantsMember" abstract="true" name="AuthorizedForFutureOptionGrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="tndm_DeferredTaxAssetsOperatingLossCarryforwardsDomesticNoExpiration" abstract="false" name="DeferredTaxAssetsOperatingLossCarryforwardsDomesticNoExpiration" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="tndm_TermLoanMember" abstract="true" name="TermLoanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="tndm_NatureOfOperationPolicyTextBlock" abstract="false" name="NatureOfOperationPolicyTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType"/>
  <xs:element id="tndm_CommonStockWarrantExpiringBetweenAugust2021andAugust2022Member" abstract="true" name="CommonStockWarrantExpiringBetweenAugust2021andAugust2022Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="tndm_StockOptionsIssuedAndOutstandingMember" abstract="true" name="StockOptionsIssuedAndOutstandingMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="tndm_HighBluffDriveSanDiegoCaliforniaMember" abstract="true" name="HighBluffDriveSanDiegoCaliforniaMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="tndm_CashCashEquivalentsAndShortTermInvestmentsTable" abstract="true" name="CashCashEquivalentsAndShortTermInvestmentsTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="tndm_IncomeTaxDisclosureLineItems" abstract="true" name="IncomeTaxDisclosureLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="tndm_ShortTermInvestmentsPolicyTextBlock" abstract="false" name="ShortTermInvestmentsPolicyTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType"/>
  <xs:element id="tndm_OrganizationAndBasisOfPresentationLineItems" abstract="true" name="OrganizationAndBasisOfPresentationLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="tndm_NumberOfLegalProceedingsRegulatoryMattersOrOtherDisputesOrClaims" abstract="false" name="NumberOfLegalProceedingsRegulatoryMattersOrOtherDisputesOrClaims" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="tndm_StockIssuedDuringPeriodSharesCommonStockWarrantsExercised" abstract="false" name="StockIssuedDuringPeriodSharesCommonStockWarrantsExercised" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="tndm_ShortTermInvestmentsMaturity" abstract="false" name="ShortTermInvestmentsMaturity" 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_CommonStockWarrantExpiringMarch2027Member" abstract="true" name="CommonStockWarrantExpiringMarch2027Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="tndm_SecondaryPublicOfferingMember" abstract="true" name="SecondaryPublicOfferingMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="tndm_VistaSorrentoParkwayLeaseMember" abstract="true" name="VistaSorrentoParkwayLeaseMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="tndm_DebtIssuanceCostsNetEquityComponent" abstract="false" name="DebtIssuanceCostsNetEquityComponent" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="tndm_LesseeOperatingLeaseCommitment" abstract="false" name="LesseeOperatingLeaseCommitment" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" 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:schema>
