TMI7301

TMI7301 provides a complete interface for a  powered device (PD) to comply with the IEEE®  802.3af standard in a Power-over-Ethernet (PoE)  system. TMI7301 provides the PD with a detection  signature, classification signature, and an  integrated isolation power switch with inrush  current control. During the inrush period, TMI7301 limit the current to less than 150mA before  switching to the higher current limit (400mA to  500mA) when the isolation power MOSFET is fully  enhanced. The device features an input UVLO with  wide hysteresis and long deglitch time to  compensate for twisted-pair cable resistive drop  and to assure glitch-free transition during poweron/-off conditions. TMI7301 can withstand up to  100V at the input. TMI7301 also provides a power-good (PG) signal, two- step current limit and foldback, over temperature protection, and di/dt limit. TMI7301 automatically generates the necessary  pulsed current to maintain the PSE power. An  external resistor is used to enable this functionality  and to program the MPS pulsed current amplitude