Littelfuse Hamlin 磁簧开关、位置传感器选型指南

PRODUCTCATALOG&DESIGNGUIDEProximity|Level|Speed|FlowAboutThisGuideThisguideprovidesanintroductiontomagneticsensingandoptionsforvalue-addedcustomdesignpackages.Italsoofferspracticalsuggestionsforselectingreedswitches,reedsensorsandHalleffectsensorsforavarietyofapplications.TopicPageIntroductiontoMagneticSensing2–3Value-AddedCustomization3ReedSwitches4–5HallEffectSensors7ReedSensors8–9ReedRelays10MagneticActuators11Applications12–15WHYCHOOSELITTELFUSELittelfuse,Inc.isthegloballeaderincircuitprotectionsolutions.Ourcompanyoffersthebroadestspectrumofcircuitprotectiontechnologiesalongwithproductsthatcanbeusedinanyapplicationthatrequireselectricalenergy.Complementingourvastportfolioofcircuitprotectionproductsisaglobalnetworkoftechnicalsupportanddesignexpertise.Usingourdecadesofdesignexperience,wehelpyouaddressuniqueapplicationchallengesandachieveregulatorycompliance.YourSingleSourceLittelfuseofferstheworld’smostdiverseandextensivecircuitprotectionproductline.Ifwedonothaveanoff-the-shelfproducttomeetyourneeds,wewillworkwithyoutodevelopaforward-thinkingsolutionthatpreciselyfitsyourapplication.Ourgoalistoprovidethemostcomprehensiverangeofoptionssothatyouwillnothavetomakecompromisesinyourdesigns.TestingSupportThroughournetworkofGlobalLabslocatedinChina,Germany,Japan,Mexico,PhilippinesandtheU.S.,wedesigninnovativecircuitprotectionsolutionsandprovidecustomerapplicationsupportandtesting.Ouruniquecapabilitiesincludeperformancetesting,materialanalysisandregulatorycompliancetesting.ThededicationofourGlobalLabsensurestheoutstandingperformance,safetyandreliabilityofourproductsandsupportservicesforourworldwidecustomerbase.ApplicationKnowledgeAtLittelfuse,ourexpertiseinvolvesapplyingreliableandefficientcircuitprotectionsolutions,innovativetechnologiesandglobalresourcestoaddresscircuitprotectionchallengesinavarietyofapplications.Weutilizeaworldwidenetworkofresearchteamsthatfocusonproductdevelopmentandsupport,design-inprogramsandapplicationtestinginourGlobalLabs.GlobalSupportLittelfuseproducts,applicationknowledgeandtechnicalsupportareavailablearoundtheglobe.Weofferanetworkofregionalcustomersupportofficesandhundredsofauthorizeddistributorstoassistyouwithyourcircuitprotectionrequirements.WHYCHOOSELITTELFUSESENSORSHamlin,nowpartofLittelfuse,Inc.,hasalong,richhistoryofleadingtheindustryinprovidingmagneticsensingsolutions.Ourexpertsarecommittedtodeliveringthebestproductsandsolutionsforyourspecificneeds.Ourglobalorganizationprovides:tCustomsensordesignspercustomerspecificationstVerticallyintegratedmanufacturingtIn-housemagneticsimulationsupporttQuickturnaroundforcustomsensorprototypesQualityAssuranceOurglobalmanufacturingfacilitiesabidebystrictqualityassurancerequirementsandholdthefollowingqualitymanagementsystemregistrations:1hamlin.com|littelfuse.com59135(High-TemperatureFlangeMountReedSensor)59010(Ultra-MiniFirecracker)MDCG-4(ReedSwitch)59050(OvermoldedReedSwitch)55140(FlangeMountHallEffectSensor)LittelfuseelectronicsproductportfolioincludesHamlinREEDSWITCHESAreedswitchhastwoferromagneticblades(reeds)containedwithinatubularglassenvelopethatishermeticallysealedateachend.Thecontactsoneachreedbladehaveathinlayerofpreciousmetalmaterialdepositedonthem.Thereisusuallynitrogengasontheinsideoftheglassenvelopetoeliminatethepresenceofoxygenandensurethatthecontactswillnotoxidize.Reedswitchesareactivatedbyapermanentmagnetoranelectromagnet.Thereedswitchandmagneticfieldcombinationiscommonlyknownasthe“magneticcircuit.”REEDSENSORSReedsensorsarereedswitchesthatarepackagedwithinanexternalhousingforsimplifiedmounting/connectingandadditionalprotectionagainstenvironmentalinfluences.Thesesensorsaretypicallymountedinmechanicalsystems.Abarereedswitchcaneasilybemountedoncircuitboards.However,foranapplicationsuchasadoorsecuritysensor,thereedswitchneedsaprotectiveshell/housingforhandlingandmounting.Thesepackagesofferresistancetomechanicalstressbyprotectingthebareglassofthereedswitch.REEDRELAYSAreedrelayismadebycombiningareedswitchwithacoppercoil.Likeotherrelays,thisprovidesgalvanicisolationbetweenthecoilinputandthecontrolledcontact(s).However,becauseofthesmallsizeandmagneticefficiencyofthereedswitch,thepowerrequiredtodrivethecoilislowerthanmostothertypesofrelays.Otheradvantagesincludehighinsulationresistance,lowcontactresistanceandlongcontactlife.Reedrelaysareusedinmanyapplications,includingautomotive,testequipment,security,medicalandprocesscontrolequipment.ComparingReedvs.HallEffectAlthoughtherearedifferencesbetweenreedswitchandHalleffecttechnologies,bothplatformsofferpracticaladvantagesforvariousapplications.Hereisacomparisonofthebenefitsofeachtechnology.2ReedSwitchHallEffectSensortNoncontactsensingelementttZeropowerconsumptionHigh-FrequencyoperationttDigitalswitchingtLinearsensingtIntegratedcircuitrytUltra-smallpackagesizettElectricalloadcapabilitytEMC/ESDimmunityOPENHoldCloseMAGNET-XmmXmmX-XOYmmSNYFigure2-Two-polelinearactivation,parallelorientationOPENHoldCloseMAGNET-XmmXmmX-XOYmmSNYCloseOPENHoldFigure3-Single-polelinearactivation,perpendicularorientationFigure