- 您现在的位置：买卖IC网 > PDF目录80048 > LTC4266IUHF#PBF (LINEAR TECHNOLOGY CORP) POWER SUPPLY MANAGEMENT CKT, PQCC38 PDF资料下载
参数资料
| 型号： | LTC4266IUHF#PBF |
| 厂商： | LINEAR TECHNOLOGY CORP |
| 元件分类： | 电源管理 |
| 英文描述： | POWER SUPPLY MANAGEMENT CKT, PQCC38 |
| 封装： | 5 X 7 MM, LEAD FREE, PLASTIC, MO-220WHKD, QFN-38 |
| 文件页数： | 17/30页 |
| 文件大小： | 414K |
| 代理商： | LTC4266IUHF#PBF |
第1页第2页第3页第4页第5页第6页第7页第8页第9页第10页第11页第12页第13页第14页第15页第16页当前第17页第18页第19页第20页第21页第22页第23页第24页第25页第26页第27页第28页第29页第30页
LTC4266
4266fa
ApplicAtions inForMAtion
voltagetransientontheVEEsupplyandpossiblycausing
theLTC4266toresetduetoaUVLOfault.A1μF,100V
X7RcapacitorplacedneartheVEEpinisrecommended
tominimizespuriousresets.
IsolatingtheSerialBus
TheLTC4266includesasplitSDApin(SDAINandSDAOUT)
toeaseopto-isolationofthebidirectionalSDAline.
IEEE802.3Ethernetspecificationsrequirethatnetwork
segments(includingPoEcircuitry)beelectricallyisolated
fromthechassisgroundofeachnetworkinterfacedevice.
However,networksegmentsarenotrequiredtobeisolated
fromeachother,providedthatthesegmentsareconnected
todevicesresidingwithinasinglebuildingonasingle
powerdistributionsystem.
ForsimpledevicessuchassmallPoEswitches,theisola-
tionrequirementcanbemetbyusinganisolatedmain
powersupplyfortheentiredevice.Thisstrategycanbe
usedifthedevicehasnoelectricallyconductingports
otherthantwisted-pairEthernet.Inthiscase,theSDAIN
andSDAOUTpinscanbetiedtogetherandwillactasa
standardI2C/SMBusSDApin.
Ifthedeviceispartofalargersystem,containsadditional
external non-Ethernet ports, or must be referenced to
protectivegroundforsomeotherreason,thePowerover
Ethernet subsystem (including all LTC4266s) must be
electricallyisolatedfromtherestofthesystem.Figure18
showsatypicalisolatedserialinterface.TheSDAOUTpin
oftheLTC4266isdesignedtodrivetheinputsofanopto-
coupler directly. Standard I2C/SMBus devices typically
cannotdriveopto-couplers,soU1isusedtobufferthe
signalsfromthehostcontrollerside.
ExternalMOSFET
CarefulselectionofthepowerMOSFETiscriticaltosystem
reliability.LTCrecommendseitherFairchildIRFM120A,
FDT3612, FDMC3612 or Philips PHT6NQ10T for their
provenreliabilityinType1andType2PSEapplications.
Non-standardapplicationsthatprovidemorecurrentthan
the850mAIEEEmaximummayrequireheatsinkingand
otherMOSFETdesignconsiderations.ContactLTCAp-
plicationsbeforeusingaMOSFETotherthanoneofthese
recommendedparts.
SenseR
TheLTC4266isdesignedtouseeither0.5Ωor0.25Ω
currentsenseresistors.Fornewdesigns0.25Ωisrecom-
mendedtoreducepowerdissipation;the0.5Ωoptionis
intendedforexistingsystemswheretheLTC4266isused
asadrop-inreplacementfortheLTC4258orLTC4259A.
Thelowersenseresistorvaluesreduceheatdissipation.
Fourcommonlyavailable1Ωresistors(0402orlarger
packagesize)canbeusedinparallelinplaceofasingle
0.25Ωresistor.InordertomeettheICUTandILIMaccuracy
required by the IEEE specification, the sense resistors
shouldhave±1%toleranceorbetter,andnomorethan
±200ppm/°Ctemperaturecoefficient.
Figure17.PositiveVDDBoostConverter
4266 F17
R54
56k
C79
2200pF
GND
ITH/RUN
LTC3803
VCC
2
5
VFB
1
3
NGATE
Q15
FDC2512
Q13
FMMT723
Q14
FMMT723
SENSE
6
4
VEE
C74
100F
6.3V
C75
10F
16V
L3
100H
SUMIDA CDRH5D28-101NC
R51
4.7k
1%
R53
4.7k
1%
R52
3.32k
1%
3.3V AT 400mA
R55
806
1%
R59
0.100
1%, 1W
R56
47.5k
1%
R57
1k
D28
B1100
R58
10
R60
10
C73
10F
6.3V
L4
10H
SUMIDA CDRH4D28-100NC
+
C77
0.22F
100V
C78
0.22F
100V
C76
10F
63V
相关PDF资料 |
PDF描述 |
|---|---|
| LT3495EDDB#TRPBF | 0.78 A SWITCHING REGULATOR, PDSO10 |
| LT1740-7PGB1 | 1-OUTPUT AC-DC REG PWR SUPPLY MODULE |
| LSN-3.3/10-D12BH | 1-OUTPUT DC-DC REG PWR SUPPLY MODULE |
| LM2575TV-12G | 3.2 A SWITCHING REGULATOR, 63 kHz SWITCHING FREQ-MAX, PZFM5 |
| LPD5.2SP | 1-OUTPUT 50 W DC-DC REG PWR SUPPLY MODULE |
相关代理商/技术参数 |
参数描述 |
|---|---|
| LTC4267 | 制造商:LINER 制造商全称:Linear Technology 功能描述:Quad IEEE 802.3at Power over Ethernet Controller |
| LTC4267-1 | 制造商:LINER 制造商全称:Linear Technology 功能描述:Power over Ethernet IEEE 802.3af PD Interface with Integrated Switching Regulator |
| LTC4267-3 | 制造商:LINER 制造商全称:Linear Technology 功能描述:Power over Ethernet IEEE 802.3af PD Interface with Integrated Switching Regulator |
| LTC4267CDHC | 制造商:Linear Technology 功能描述:Hot Swap Controller 1-CH -57V 16-Pin DFN EP |
| LTC4267CDHC#PBF | 功能描述:IC POE 802.3AF INTERFACE 16-DFN RoHS:是 类别:集成电路 (IC) >> 接口 - 控制器 系列:- 标准包装:2,450 系列:- 控制器类型:SPI 总线至 I²C 总线桥接 接口:I²C，串行，SPI 电源电压:2.4 V ~ 3.6 V 电流 - 电源:11mA 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:24-VFQFN 裸露焊盘 供应商设备封装:24-HVQFN（4x4） 包装:托盘 配用:568-3511-ND - DEMO BOARD SPI TO I2C 其它名称:935286452157SC18IS600IBSSC18IS600IBS-ND |
发布紧急采购，3分钟左右您将得到回复。