What this USB switch brings to a power rail
The NXP NX5P3001UKZ is a single-channel high-side USB power switch in the NX5 series, built to handle up to 3 A continuous through a typical 62 mOhm Rds(on) N-channel MOSFET. The load supply range spans 3 V to 30 V, so it covers 5 V USB rails, 12 V automotive accessory ports, and 24 V industrial power buses without a separate regulator. The 62 mOhm typical Rds(on) keeps conduction loss under 0.6 W at full 3 A load — manageable in the 12-WLCSP package if the PCB copper pours and vias are sized to pull heat out of the 1.6 mm x 1.3 mm footprint. At lower currents the dissipation drops proportionally, which matters when you're routing a 3 A rail through a tiny BGA-style land pattern.
Protection set: adjustable current limit, OTP, UVLO
Three fault protections are integrated: adjustable current limiting (set with an external resistor), over-temperature shutdown, and under-voltage lockout. The adjustable limit means you can tailor the trip point to the load — useful when the downstream circuitry has a known inrush profile or a specific cable-drop budget. Over-temperature protection catches the case where a shorted load or high ambient drives the die past the 125°C junction rating, and UVLO prevents the switch from turning on when the input supply is too low to keep the gate drive clean.
Active lifecycle, ROHS3, and the WLCSP package reality
The 12-WLCSP package (1.6 mm x 1.3 mm) is a fine-pitch BGA-style land grid; rework requires a hot-air station with a preheat plate and a steady hand. The solder balls are under the part, so orientation is marked by the corner ball pattern — verify the datasheet's top-view diagram before placing.