Datasheet Linear Technology LTC4257CS8#PBF — Даташит

Производитель	Linear Technology
Серия	LTC4257
Модель	LTC4257CS8#PBF

Контроллер интерфейса IEEE 802.3af PD Power over Ethernet

Datasheets

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PDF, 270 Кб, Версия: B, Файл закачен: 25 окт 2017

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Цены

Купить LTC4257CS8#PBF на РадиоЛоцман.Цены — от 31 до 341 ₽ 46 предложений от 25 поставщиков Single PoE+ PSE Controller High Capacitance Legacy Device Detection
AllElco Electronics Весь мир	LTC4257CS8#PBF Analog Devices	от 40 ₽
EIS Components Весь мир	LTC4257CS8#PBF Analog Devices	125 ₽
ЭИК Россия	LTC4257CS8#PBF Analog Devices	от 341 ₽
ЭлектроПласт Россия	LTC4257CS8-1#PBF Linear Technology	по запросу

Корпус / Упаковка / Маркировка

Корпус	SO-8
Код корпуса	S8
Индекс корпуса	05-08-1610 (S8)

Параметры

Количество каналов	1
Design Tools	LTspice Model
Экспортный контроль	нет
I2C Interface	нет
IEEE-Compliant Classification	One Event
IEEE-Compliant Detection	Yes (Internal 25k resistor)
IEEE-Compliant Disconnection	N/A
Max Power	13 W
Рабочий диапазон температур	от 0 до 70 °C
PSE/PD	PD
PoE Type	1

Экологический статус

RoHS

Совместим

Design Notes

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Power over Ethernet Isolated Power Supply Delivers 11.5W at 90% Efficiency &mdash DN338
PDF, 80 Кб, Файл опубликован: 2 май 2004
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Power over Ethernet Isolated Power Supply
Delivers 11.5W at 90% Efficiency вЂ“ Design Note 338
Jesus Rosales
fewer switches to turn on and off the better. A push-pull
converter could be used, but the additional complexity
is not justiп¬Ѓed at this power level. A single transistor
forward converter is another option, but requires
an additional output inductor and rectiп¬Ѓer. A п¬‚yback
converter is the simplest choice. Flyback converters
are thought to be less efп¬Ѓcient than forward and pushpull converters, but that changes when the output is
synchronously rectiп¬Ѓed (a MOSFET is used instead of
a diode to rectify the output). When powering IP telephones, wireless access points,
PDA charging stations and other PDs (Powered Devices)
from an Ethernet cable, designers have at most 12.95W
of available power per the IEEE 802.3af standard. Increased demands for power mandate a very efп¬Ѓcient
power converter especially for classВ 3 devices (consuming between 6.49W and 12.95W). The more power lost
in the converter, the less power available for the PD.
The voltage available from the PSE (Power Sourcing
Equipment) ranges from 44V to 57V, but PDs need to
operate with as much as 20О© of series wire resistance.
A PD can never draw more than 350mA or 12.95W
continuously. With the maximum input current of
350mARMS, the input voltage can droop as much as …

Модельный ряд

Серия: LTC4257 (8)

LTC4257CDD#PBF LTC4257CDD#TRPBF LTC4257CS8#PBF LTC4257CS8#TRPBF LTC4257IDD#PBF LTC4257IDD#TRPBF LTC4257IS8#PBF LTC4257IS8#TRPBF

Классификация производителя

Monitor, Control and Protection > Power-over-Ethernet (PoE) Interface Controllers > PoE Powered Device (PD)

Варианты написания:

LTC4257CS8PBF, LTC4257CS8 PBF