LINEAR TECHNOLOGY DC804A-B Evaluation Board, IEEE 802.3Af Power Device, With Integrated Switching Regulator Drive 6V MOSFET
demonstration board is a power over Ethernet power device interface with integrated switching regulator featuring the LTC4267. It provides a complete IEEE 802.3af power device interface and isolated 3.3V power supply solution for use in Power over Ethernet applications. The LTC4267 integrates the 25kohm signature resistor, classification current source, thermal overload protection, signature disable and power good signal along with an undervoltage lockout optimized for use with the IEEE required diode bridge. The precision dual level input current limit allows the LTC4267 to charge large load capacitors and interface with legacy PoE systems. The LTC4267 combines the above features with a current mode switching controller designed for driving a 6V rated N-channel MOSFET. It features programmable slope compensation, softstart, and constant frequency operation, minimizing electrical noise even with light loads. DC804A-B is designed to produce 3.3V power for a class 2 PD.