TPS23757

www.ti.com TPS23757 SLVS948D – JULY 2009 – REVISED NOVEMBER 2013 High Efficiency PoE Interface and DC/DC Controller FEATURES 1 Powers up to 13 W (Input) PDs Legacy and IEEE 802.3at Type 1 PDs Optimized for Isolated DC/DC Converters Supports High-Efficiency Topologies Complete PoE Interface Adapter ORing Support Programmable Frequency with Synch. Robust 100 V, 0.5 Ω Hotswap MOSFET Pin Compatible with TPS23754/6 –40°C to 125°C Junction Temperature Range Industry Standard TSSOP-20 APPLICATIONS IEEE 802.3at Type 1 Compliant Devices Video and VoIP Telephones Access Points Security Cameras DESCRIPTION The TPS23757 is a combined Power over Ethernet (PoE) powered device (PD) interface and currentmode dc/dc controller optimized specifically for isolated converters. The PoE interface supports the IEEE 802.3at standard for a type 1 PD, which is equivalent to the 13W standard of IEEE 802.3-2008. The TPS23757 supports a number of input voltage ORing options including highest voltage, external adapter preference, and PoE preference. The TPS23757 has an output flag indicating if an external wall adapter is active when used in conjunction with ORing controls. The detection signature pin can also be used to force power from the PoE source off. Classification can be programmed to any of the defined types with a single resistor. The dc/dc controller features two complementary gate drivers with programmable dead time. This simplifies design of highly-efficient fl...