53 mOhm on-resistance at 4.5 V drive
The CSD23202W10: The 53 mOhm Rds(on) at 4.5 V gate drive is the number that sizes the conduction loss — at 500 mA load the voltage drop is under 27 mV, which keeps the dissipation below 14 mW in a typical load-switch application. The 1x1 mm 4-DSBGA package puts the die right at the board surface, so the thermal path is through the solder balls and the PCB copper, not a plastic overmold.
Gate charge and switching speed
Total gate charge is 3.8 nC at 4.5 V, with an input capacitance of 512 pF at 6 V drain bias.
Package and mounting
The 4-DSBGA (1x1 mm) package has four solder balls on a 0.5 mm pitch. No exposed pad, no centre thermal via — the die heat spreads through the BGA balls into the PCB pads. In a field-repair scenario this is not a hand-solder part; you need a hot-air station with a fine nozzle and a stencil for the solder paste. The package marking is minimal — confirm orientation by the pin-1 indicator (a dot or chamfer on the package corner) before placement. Moisture sensitivity level is not listed in the spec, but a 1x1 mm BGA typically runs MSL-1; still, bake at 125 °C for 8 hours if the reel has been open longer than the floor life.