Make ProvisionedThroughput optional or Novalue

Want to create a common product to create a dynamodb table which supports either one of the options (BillingMode or ProvisionedThroughput). Lets say in the below example if the user has provided BillingMode , ProvisionedThroughput should be skipped. Is there way I can add condition for parameters which takes multiple values?

  ProvisionedThroughput:
    ReadCapacityUnits: !Ref rUnits
    WriteCapacityUnits: !Ref wUnits
  BillingMode:
    !If [ UseBillingMode, !Ref BillingMode, !Ref "AWS::NoValue" ]