德州仪器POE芯片TPS23785B具有绿色环保模式的高功耗、

TPS23785BM1RCSDVC1GATERTNVCCSCVCCTL58V0.1uFRDENFromEthernetPairs1,2VSSCINFromEthernetPairs3,4CLSDENFRST2PRCLSType2PSEIndicatorRFRSVBCVBRFBURFBLTLV431CIZVOUTPADVDDGAT2M2RT2PDARAPD2RAPD1AdapterRCTLAPDCOUTT1RVCARTNNCVDD1COMRBLNKBLNKDTRDTTPS23785B–DECEMBER2012–REVISEDDECEMBER2012高高功功率率、、高高效效PoE受受电电设设备备(PD)和和DC至至DC控控制制器器1特特性性说说明明2•功功率率高高达达30W（（输输入入））PDTPS23785B是一款将以太网供电(PoE)受电设备(PD)接口与电流模式DC至DC控制器（针对非隔离•针针对对非非隔隔离离转转换换器器对对DC至至DC控控制制进进行行了了优优化化转换器进行了优化）组合在一起的器件。此PoE接口•支支持持高高效效拓拓扑扑结结构构支持IEEE802.3at标准。•完完整整的的PoE接接口口•符符合合IEEE802.3at标标准准且且具具有有状状态态标标志志的的增增强强型型TPS23785B支持一定数量的输入电压ORing选项，分分类类其中包括最高电压、外部适配器基准和PoE优先选•适适配配器器或或运运算算(ORing)支支持持择。这些特性使得设计人员能够确定哪个电源在所有•稳稳定定耐耐用用的的100V，，0.5Ω热热插插拔拔金金属属氧氧化化物物半半导导体体情况下来承担负载。场场效效应应晶晶体体管管(MOSFET)PoE接口特有与高功率中跨式供电设备(PSE)（符合•-40°C至至125°C的的工工作作结结点点温温范范围围IEEE802.3at标准）兼容所需的两事件、物理层分•行行业业标标准准PowerPAD™薄薄型型小小外外形形尺尺寸寸(TSSOP)-24封封装装类。签名检测引脚也可被用来强制关闭PoE供电。使用一个单个电阻器可将分类设定为已定义类别中的任应应用用范范围围何一个。•IEEE802.3at兼兼容容器器件件•视视频频和和网网络络语语音音(VoIP)电电话话•RFID阅阅读读器器•监监控控摄摄像像机机•无无线线访访问问点点设设备备典典型型应应用用图图1Pleasebeawarethatanimportantnoticeconcerningavailability,standardwarranty,anduseincriticalapplicationsofTexasInstrumentssemiconductorproductsanddisclaimerstheretoappearsattheendofthisdatasheet.2PowerPADisatrademarkofTexasInstruments.PRODUCTIONDATAinformationiscurrentasofpublicationdate.版权©2012,TexasInstrumentsIncorporatedProductsconformtospecificationsperthetermsoftheTexasInstrumentsstandardwarranty.ProductionprocessingdoesnotEnglishDataSheet:SLUSB90necessarilyincludetestingofallparameters.TPS23785BZHCSAN5A–DECEMBER2012–REVISEDDECEMBER2012说说明明（（续续））DC至DC控制器特有两个支持可编程死区时间的互补栅极驱动器。这样简化了采用次级同步整流的高效反激式拓扑结构的设计。如果需要单一MOSFET拓扑，可将第二栅极驱动器禁用。此控制器还特有内部软启动、引导加载程序启动源、电流模式补偿和一个最大值为78%的占空比。一个可编程和可同步振荡器可针对使用效率对设计进行优化并简化控制器的使用以升级现有的电源设计。具有一个缺省周期的精确可编程消隐简化了常见电流感测滤波器设计平衡。ThisintegratedcircuitcanbedamagedbyESD.TexasInstrumentsrecommendsthatallintegratedcircuitsbehandledwithappropriateprecautions.Failuretoobserveproperhandlingandinstallationprocedurescancausedamage.ESDdamagecanrangefromsubtleperformancedegradationtocompletedevicefailure.Precisionintegratedcircuitsmaybemoresusceptibletodamagebecauseverysmallparametricchangescouldcausethedevicenottomeetitspublishedspecifications.PRODUCTINFORMATION(1)POEUVLOCONVERTERUVLODUTYCYCLEON/HYST.ON/HYST.PACKAGEMARKING(V)(V)TPS23785BPWP0–78%35/4.515/6.5TSSOP-24PowerPAD™TPS23785B(1)Forthemostcurrentpackageandorderinginformation,seethePackageOptionAddendumattheendofthisdocument,orconsultyourTIsalesperson.ABSOLUTEMAXIMUMRATINGS(1)(2)VoltagewithrespecttoVSSunlessotherwisenoted.Overrecommendedoperatingjunctiontemperaturerange.VALUEUNITARTN(2),COM(2),DEN,RTN(3),VDD,VDD1–0.3to100CLS(4)-0.3to6.5[APD,BLNK(4),CTL,DT(4),FRS(4),VB(4)]to[ARTN,–0.3to6.5COM]Inputvoltagerange[P1,P2(4)]to[ARTN,COM]–0.3to6.5VCSto[ARTN,COM]–0.3toVB[ARTN,COM]toRTN–2to2T2P(4),VCto[ARTN,COM]–0.3to19VoltagerangeGATE(4),GAT2(4)to[ARTN,COM]–0.3toVC+0.3RTNInternallylimitedSinkingcurrentT2P20mASourcingcurrentVBInternallylimitedAverageSourcingorGATE,GAT225mARMSsinkingcurrentHumanbodymodel(HBM)2kVESDratingChargeddevicemodel(CDM)500VMachinemodel(MM)50ESD–systemlevel(contact/air)atRJ-45(5)8/15kVOperatingjunctiontemperaturerange,TJ–40toInternallylimited°C(1)Stressesbeyondthoselistedunderabsolutemaximumratingsmaycausepermanentdamagetothedevice.Thesearestressratingsonlyandfunctionaloperationofthedeviceattheseoranyotherconditionsbeyondthoseindicatedunderrecommendedoperatingconditionsisnotimplied.Exposuretoabsolute-maximum-ratedconditionsforextendedperiodsmayaffectdevicereliability.(2)ARTNandCOMtiedtoRTN.(3)IRTN=0forVRTN80V.(4)Donotapplyvoltagetothesepins(5)ESDperEN61000-4-2.ApowersupplycontainingtheTPS23785Bwassubjectedtothehighesttestlevelsinthestandard.2Copyright©2012,TexasInstrumentsIncorporatedTPS23785B–DECEMBER2012–REVISEDDECEMBER2012RECOMMENDEDOPERATINGCONDITIONS(1)VoltagewithrespecttoVSS(unlessotherwisenoted)MINNOMMAXUNITARTN,COM,RTN,VDD,VDD1057T2P(2),VCto[ARTN,COM]018InputvoltagerangeV[APD,CTL,DT,FRS(3),P1,P2]to[ARTN,COM]0VBCSto[ARTN,COM]02SinkingcurrentT2P2ContinuousRTNcurrent(TJ≤125°C)(4)825mASourcingcurrentVB02.55CapacitanceVB0.08μFRBLNK0350kΩSynchronizationpulsewidthinput(whenused)25nsOperatingjunctiontemperaturerange,TJ–40125°C(1)ARTNandCOMtiedtoRTN.(2)T2Pcurrentislimited.(3)Pulsevoltageappliedforsynchronization.(4)Thisistheminimumcurrent-limitvalue.Viablesystemswillbedesignedformaximumcurrentsbelowthisvaluewithreasonablemargin.IEEE802.3atpermits600mAcontinuousloading.THERMALINFORMATIONTPS23785BTHERMALMETRIC(1)TSSOPUNITS24PINSθJAJunction-to-ambientthermalresistance(2)32.6θJCtopJunction-to-case(top)thermalresistance(3)16.9θJBJunction-to-boardthermalresistance(4)17.9°C/WψJTJunction-to-topcharacterizationparameter(5)0.2ψJBJunction-to-boardcharacterizationparameter(6)7.4θJCbotJunction-to-case(bottom)thermalresistance(7)1.8(1)有关传统和新的热度量的更多信息，请参阅IC封装热度量应用报告，SPRA953。(2)在JESD51-2a描述的环境中，按照JESD51-7的指定，在一个JEDEC标准高K电路板上进行仿真，从而获得自然对流条件下的结至环境热阻。(3)通过在封装顶部模拟一个冷板测试来获得结至芯片外壳（顶部）的热阻。不存在特定的JEDEC标准测试，但可在AN