eaturesandBenefitsChopperstabilizedamplifierstageOptimizedforbrushlessDCmotorapplicationsMiniaturehighreliabilitypackageOperationdownto3.5VCMOSforoptimumstability,qualityandcostLowpowerconsumptionOrderingInformationPartNo.US1881US1881US1881TemperatureSuffixE(-40 Cto85 C)K(-40 Cto125 C)L(-40 Cto150 C)PackageCodeSO(SOT-23)orUA(TO-92)SO(SOT-23)orUA(TO-92)SO(SOT-23)orUA(TO-92)ApplicationsSolidstateswitchBrushlessDCmotorcommutationSpeedSensingLinearpositionsensingAngularpositionsensingCurrentsensingPinout:UAPackage:Pin1:VDD-supplyPin2:GND-GroundPin3:OUT-OutputSOPackage:Pin1:VDD-supplyPin2:OUT OutputPin3:GND-Ground1FunctionalDiagramNote:Staticelectricitysensitivedevice;pleaseobserveESDprecautions.Reversevoltageprotectionisnotincluded.Forreversepolarityprotection,a100OhmresistorinserieswithVDDisrecommended.2DescriptionTheUS1881istheindustry sfirstHallintegratedcircuitinSOT-23package.TheUS1881isabipolarHalleffectsensorICbasedonmixedsignalCMOStechnology.Itincorporatesadvancedchopperstabilizationtechniquestoprovideaccurateandstablemagneticswitchpoints.TherearemanyapplicationsforthisHEDinadditiontothoselistedabove.Thedesign,specificationsandperformancehavebeenoptimizedforcommutationapplicationsin5Vand12VbrushlessDCmotors.InUApackageddevicetheoutputtransistorwillbelatchedon(Bop)inpresenceofasufficientlystrongSouthpolemagneticfieldfacingthemarkedsideofthepackage.Similarly,theoutputwillbelatchedoff(Brp)inthepresenceofaNorthfield.TheSOT-23devicebehaviourisreversetotheUAdevice.TheSOT-23output