What this switch does on the rail
The slew-rate controlled turn-on prevents inrush current from tripping upstream supplies or drooping the input rail — a common failure in hot-plug and USB port designs.
13 mOhm Rds(on) — what the conduction loss means
With a typical on-resistance of 13 mOhm, the TPS2559DRCT dissipates under 400 mW at 5.5 A continuous (I²R). If the board runs at 85°C ambient, the 125°C junction rating leaves about 25°C of headroom at full load, so the thermal vias under the pad matter.
Adjustable current limit sets the trip point
The current limit is set with a single resistor from the ILIM pin to ground — no external sense resistor, no voltage drop penalty. This lets you dial the trip threshold to match the downstream load: a 1.5 A USB port, a 3 A motor stall, or the full 5.5 A for a bulk-capacitor charging profile. The status flag output (open-drain, active low) asserts when the switch hits current limit or thermal shutdown, so the system controller can log the fault or retry.
Industrial temp range and package reality
Listed as Active by the manufacturer. The base product number TPS2559 covers several current-limit and package variants, but the DRCT suffix (VSON-10, Tape & Reel) is current production.