22 µF / 4 V molded tantalum — 0805 footprint, 3.8 Ohm ESR
The TAJR226K004RNJ: This is a molded tantalum capacitor from the TAJ series, rated 22 µF at 4 V with ±10% tolerance. The 3.8 Ohm ESR at 100 kHz sets the ripple current handling and the self-heating under AC load — for a 4 V rail, the ripple voltage budget is tight, so the ESR directly limits the decoupling effectiveness on a switching supply output.
The 0805 case (2.05mm x 1.30mm) is a standard footprint; the size code R helps identify the can height (1.20 mm seated max) for clearance checks under low-profile components.