is a combined Power over Ethernet (PoE) powered device (PD) Interface
and current-mode dc/dc controller optimized specifically for isolated converter designs. The PoE implementation supports the IEEE 802.3-2005 (previously 802.3af) standard, 12.95 W (13 W) PD. The TPS23753
supports a number of input-voltage ORing options including highest voltage, external adapter preference, and PoE preference. The PoE Interface
features an external detection signature pin that can also be used to disable the internal hotswap MOSFET. This allows the PoE function to be turned off. Classification can be programmed to any of the defined types with a single Resistor
The dc/dc controller features a bootstrap startup mechanism with an internal, switched current source. This provides the advantages of cycling overload fault protection without the constant power loss of a pull up Resistor
The programmable Oscillator
may be synchronized to a higher-frequency external timing reference.