IC datasheet pdf-AS3691,pdf (4x400mA Precision Cur

AS3691Datasheet(ptr)Revision2.31-221GeneralDescriptionTheAS3691(AS3691AandAS3691B)featuresfourhighprecisioncurrentsourcesforlightingofuptofourLEDstrings(RGBorsinglecolorleds).EachofthefourcurrentssourcescanbecontrolledindependentlybyPWMinputs.Thefullscalecurrentvalueissetbyexternalresistors.2KeyFeaturesƒ4xupto0.4AconstantcurrentoutputsƒProgrammablewithexternalresistorsƒ4independentPWMinputsƒAbsolutecurrentaccuracy+/-0.5%ƒ’AutomaticSupplyRegulation’toreducepowerdissipation1)1)PatentPendingƒVerywideoutputvoltagecurrentsourcevoltagecompliance−Downto0.41V−Upto15V2)ƒIntegratedovertemperatureprotectionƒSeparatesensepads(Rfb1-Rfb4)foreasyandprecisePCBLayoutƒPackage−DIE−QFN244x4mm−eP-TSSOP2)15VissufficientformostapplicationsastheAS3691dosenotswitchofftheLEDcurrentcompletely3ApplicationsƒGeneralLightingƒBacklightingƒRGBBacklightingforLCDTV/MonitorswithWhiteColorBalancing4ApplicationDiagramsFigure1–ApplicationDiagramofAS3691forSingleColorLightingVSSVSSVDDVDDRi1Ri2Ri3Ri4RvddCvdd100nFUVUVPWMPWMRefOvertempAS3691T1T2T3T4D1R1R2R3R4VREGVSSON1ON2ON3ON4CURR1CURR2CURR3CURR4RES1RES2RES3RES4I1UV1VcUV2UV3UV4I2I3I4VcVcVcRFB1RFB2RFB3RFB4Csup100nFPadDatasheetAS36914Precision400mACurrentSourcesforRGBandSingleColorLedsAS3691Datasheet(ptr)Revision2.32-22Figure2–ApplicationDiagramofAS3691forRGBLightingVSSVSSVDDRVDDRRi1Ri2Ri3Ri4RvddUVRUVRUVBUVBUVGUVGPWMRPWMRPWMBPWMBPWMGPWMGVDDBVDDBVDDGVDDGRefOvertempAS3691T1T2T3T4D1R1R2R3R4VREGVSSON1ON2ON3ON4CURR1CURR2CURR3CURR4RES1RES2RES3RES4I1UV1VcUV2UV3UV4I2I3I4VcVcVcRFB1RFB2RFB3RFB4Cvdd100nFPadAS3691Datasheet(ptr)Revision2.33-22TableofContents1GeneralDescription.........................................................................................................................................12KeyFeatures....................................................................................................................................................13Applications......................................................................................................................................................14ApplicationDiagrams.......................................................................................................................................15Pinout...............................................................................................................................................................45.1PinAssignments.......................................................................................................................................45.2PinDescriptions........................................................................................................................................46Characteristics.................................................................................................................................................66.1AbsoluteMaximumRatings......................................................................................................................66.2OperatingConditions................................................................................................................................66.3ElectricalCharacteristics...........................................................................................................................77TypicalOperationCharacteristics....................................................................................................................88DetailedFunctionalDescription.....................................................................................................................128.1ShuntRegulator......................................................................................................................................128.2OvertemperatureProtection....................................................................................................................128.3AutomaticSupplyRegulation..................................................................................................................139ApplicationInformation..................................................................................................................................149.1DesignExample......................................................................................................................................159.1.1UsingAutomaticSupplyRegulation.................................................................................................169.2LayoutRecommendations......................................................................................................................1610PackageDrawingsandMarkings...............................................................................................................1710.1QFN4x4PackageDrawingsandMarking..............................................................................................1710.2ePTSSOPPackageDra