20 V rated, 0805 case — what it buys the BOM
Rated 20 V with ±10% tolerance on 0.1 µF capacitance, the TAJR104K020HNJ gives 1.6× headroom above a 12 V rail — enough margin for most 5 V and 12 V decoupling without stepping up to a larger case size. The 0805 (2012 Metric) package keeps the footprint small — 2.05 mm × 1.30 mm — fitting tight PCB layouts where every square millimetre counts.
Temperature range and lifetime — where it fits
Lifetime is rated 2000 hours at 125°C — at 85°C ambient the expected life extends significantly per the Arrhenius acceleration model, but this is not a continuous high-temp automotive or engine-bay part.
ESR and frequency — what 25 Ohm at 100 kHz means
ESR is specified at 25 Ohm typical at 100 kHz — a moderate value for a 0.1 µF tantalum. For ripple current handling, the buyer should compare this against the ripple current in the circuit; a higher ESR means more self-heating at the same ripple current.