The TPS2540ARTER is a single-channel USB high-side switch from Texas Instruments, built to power a USB host port or a dedicated charging port with a continuous 2.5 A output. The 73 mOhm typical on-resistance is the number that sets the voltage drop from input to output at full load — at 2.5 A that drop is about 180 mV, so the load side still sees a solid 4.8 V from a 5 V rail.
Fault protection set — adjustable current limit, over-temperature, UVLO
The fault-protection stack covers the three failure modes that kill a USB port: a shorted cable (adjustable current limit), a stalled fan or hot-plug surge (over-temperature shutdown), and a sagging 5 V rail (UVLO). The current limit is adjustable with a single resistor, so the same board can be configured for a 500 mA legacy port or a 2.5 A charging port by changing one BOM value. The Status Flag output (open-drain, active low) tells the host controller that the switch has hit the limit or shut down — no polling, no software loop.
That means no last-time-buy window to chase, no surplus-market scramble.