Description

This reference design implements a Power over Ethernet (PoE) Class 6 Powered Device (PD) with dual redundant PoE inputs and smooth transition between these inputs and an auxiliary input. Three power sources decrease the probability of power and data loss in equipment. The auxiliary input has priority. PoE Port 1 has priority over PoE Port 2 when the auxiliary is not connected. Telemetry (input current, voltage, and power) is provided via I2C using an INA237A. Two TPS2373-3 PD controllers interface with a Power Source Equipment (PSE) on ports 1 and 2. A 5V, 9A active clamp forward converter is implemented with the PWM portion of a TPS23734 PD, PWM controller integrated circuit (IC).