The TAJS225K010RNJ is a molded tantalum capacitor from the TAJ series, rated 2.2 µF with ±10% tolerance and a 10 V working voltage. The 12 Ohm ESR is the dominant thermal parameter — at ripple current the self-heating is proportional to I² × ESR, so a 100 mA ripple dissipates 120 mW, which must be within the package's thermal budget. The 1206 (3216 Metric) footprint is a standard size for reflow assembly and fits a 0.063-inch wide pad layout.
RoHS compliance is standard for the TAJ series — confirm the specific date code at RFQ. The datasheet covers derating curves for voltage and temperature; a 50 % voltage derating is typical for tantalum capacitors in high-reliability designs.