Linear Technology LTC4257 Manuals

The LTC4257 is a complete power interface power supply chip designed for IEEE 802.3af PoE systems. It integrates 25k signature resistors, classification current sources, input current limiting with thermal foldback, undervoltage lockout, and power good signaling, all in a single 8-pin package. The chip integrates a high-voltage power MOSFET, which reduces the cost for system designers and saves board space. LTC4257 can directly interface with Linear Technology's various DC/DC converter products to provide an economical power solution for IP phones, wireless access points and other PDs. Linear Technology also provides solutions for PSE applications based on quad network power controllers. LTC4257 is available in 8-pin SO and low profile (3mm x 3mm) DFN packages.

LTC4257 is a PoE PD power interface chip for IEEE 802.3af PoE system. It integrates 25k signature resistor, classification current source, input current limit with thermal foldback, undervoltage lockout and power good signalling, all in a single 8-pin package. It can be interfaced with a variety of LT DC/DC converter products to provide a cost effective power solution for IP phones, wireless access points and other PDs.