The 76 mOhm maximum on-resistance at 4.5 V gate drive and 400 mA is the figure to use for conduction-loss estimates. At 1.8 V drive the Rds(on) is higher — the datasheet curve shows it, but the guaranteed max is at 4.5 V. If your logic rail is 1.8 V, expect higher losses; plan the copper pour accordingly. Input capacitance is 156 pF at 6 V Vds, so rise/fall times stay short even with a weak source.
Package reality — tiny, so handle with care
The 3-XFDFN / 3-PICOSTAR is a leadless package.
This part is active and ROHS3 compliant. For volume or sample quantities, we source and quote to order against an RFQ.