In this graph shown here, the power dissipation of a single passive diode bridge is compared to one of the LT4321 MOSFET bridge plotted against the PD current on the x-axis. The power savings afforded by the LT4321 is the difference between the two curves. The savings increase with current, reaching 1.6W for a 1.1A load current. In a 90W LTPoE++ system, 1.1A is the current through one bridge when the PD input voltage is at its minimum of 41V. Since LTPoE++ has both the bridges powered, the total savings is 3.2W, which is 3.6% of 90W.