This 80W telecom hot-swap reference design is immune to 150V input-voltage transients and 16ms power dropouts. Additional features include -32V to -72V operation, two-diode OR-ing input, and an inrush current that is ≤ 1.5 times the full-load current. Included are a detailed schematic, representative PCB layout, bill of materials, waveforms detailing actual performance at startup, -150V input transient, and full-load holdup at power loss.