The TPS23861 is an easy-to-use， flexible， IEEE802.3at PSE solution. As shipped， it automatically manages four 802.3at ports without the need for any external control. The TPS23861 automatically detects Powered Devices （PDs） that have a valid signature， determines power requirements according to classification and applies power. Two-event classification is supported for type-2 PDs. The TPS23861 supports DC disconnection and the external FET architecture allows designers to balance size， efficiency and solution cost requirements. The unique pin-out enables 2-layer PCB designs via logical grouping and clear upper and lower differentiation of I 2C and power pins. This delivers best-in-class thermal performance， Kelvin accuracy and low-build cost. In addition to automatic operation， the TPS23861 supports Semi-Auto Mode via I 2C control for precision monitoring and intelligent power management. Compliance with the 400-ms TPON specification is ensured whether in semi-automatic or automatic mode. D