The TMI7303B provides a complete interface for a  Powered Device (PD) with the IEEE 802.3af/at standard in PoE system. The TMI7303B include  detection signature, classification signature and an integrated isolation power switch with inrush  current control mode. It supports a 2-event  classification method as specified provide a signal  to indicate when probed by Type 2 power-sourcing  equipment (PSE). The devices detect the presence  of a wall adapter power-source connection and  allow a smooth switchover from the PoE power  source to the wall adapter. Thermal protection is  built in to accommodate both transient and/or  overload conditions, shutting the part down and  protecting the input source as well as the output  load depending on the particular fault conditions.  Inrush current limiting is included to slowly charge  the input capacitor without interruption due to die  heating, a problem encountered without the current  limit fold back feature. The TMI7303B is available in a DFN3x3-10  package with exposed pad for low thermal  resistance.