ZHCA962 October 2019
The TPS2388x device is the main IC to handle PoE functions to deliver power to PDs through Ethernet cable.
The TPS23882 is an 8-channel power sourcing equipment (PSE) controller engineered to insert power onto Ethernet cables in accordance with the IEEE 802.3bt standard. The PSE controller can detect powered devices (PDs) that have a valid signature, determine the power requirements of the devices according to their classification, and apply power. The TPS23882 improves on the TPS2388 with reduced current sense resistors, selectable Autonomous operation, SRAM programmability, programmable power limiting, capacitance measurement, and compatibility with TI's FirmPSE system firmware (see Device Comparison Table). Dedicated per port ADCs provide continuous port current monitoring and the ability to perform parallel classification measurements for faster port turn on times. A 1.25A port current limit and adjustable power limiting allows for the support of non-standard applications above 60W sourced. The 200 mΩ current sense resistor and external FET architecture allow designs to balance size, efficiency, thermal, and solution cost requirements. Port remapping and pin-to-pin compatibility with the TPS2388/80/81 devices eases migration from previous generation PSE designs and enables interchangeable 2-layer PCB designs to accommodate different system PoE power configurations.