TI TPS23754 30W大功率PoE供电方案
The TPS23754/6 is a combined Power over Ethernet (PoE) powered device (PD) interface and current-mode dc/dc controller optimized specifically for isolated converters. The PoE interface supports the IEEE 802.3at (draft) standard.
The TPS23754/6 supports a number of input voltage ORing options including highest voltage, external adapter preference, and PoE preference. These features allow the designer to determine which power source will carry the load under all conditions.
The PoE interface features the new extended hardware classification necessary for compatibility with high-power midspan power sourcing equipment (PSE) per IEEE 802.3at (draft). The detection signature pin can also be used to force power from the PoE source off. Classification can be programmed to any of the defined types with a single resistor.
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