LTC4258CGW#PBF

LINEAR TECHNOLOGY  LTC4258CGW#PBF  芯片, 以太网供电PoE控制器, 802.3af, 四路, 36SSOP

The is a quad Hot Swap Controller designed for use in IEEE 802.3af compliant power sourcing equipment PSE. It consists of four independent ports, each with output current limit, short-circuit protection, complete Powered Device PD detection and classification capability and programmable PD disconnect using DC sensing. Used with power MOSFETs and passives, the LTC4258 can implement a complete IEEE 802.3af-compliant PSE. It can operate autonomously or be controlled by an I²C serial interface. Up to 16 LTC4258s may coexist on the same data bus, allowing up to 64 powered Ethernet ports to be controlled with only two digital lines. Fault conditions are optionally signaled with the INT pin to eliminate software polling. External power MOSFETs, current sense resistors and diodes allow easy scaling of current and power dissipation levels and provide protection against voltage and current spikes and ESD events.

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IEEE 802.3af compliant PD detection and classification

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Output current limit with foldback

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Short-circuit protection with fast gate pull-down

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PD Disconnect using DC sensing

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Power good indication

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4-bit Programmable digital address allows control of up to 64 Ports

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Programmable INT pin eliminates software polling

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Current and duty cycle limits protect external FETs