DI-88, DPA423GN, PoE Detection and Classification (Class 0-3) Interface Circuit

DI-88, Reference Design for DPA423GN PoE Detection and Classification (Class 0-3) Interface Circuit. The PoE specification requires the PD to implement three functions: detection, classification and pass-switch connection. Detection occurs as the input voltages rises from 2.5 to 10VDC.Resistor R31 within the PD presents the detection impedance to the PSE