0.15 µF, 35 V — core selection check
The TAJA154K035HNJ: 0.15 µF capacitance at 35 V rated voltage with ±10% tolerance — the 35 V rating provides 2× derating margin on a 12 V rail, reducing DC bias capacitance loss in tantalum dielectrics.
21 Ohm ESR — ripple current and thermal budget
21 Ohm max ESR at 100 kHz sets the ripple current ceiling — for a 0.15 µF cap on a 100 kHz switching node, the self-heating from I²R loss stays within the 2000-hour lifetime at 125°C as long as the ripple current stays under the calculated limit per the datasheet derating curve.
1206 case — board layout fit
1206 (3216 Metric) case, size code A, measures 3.20 mm × 1.60 mm with a seated height of 1.80 mm — surface-mount reflow assembly, compatible with standard pick-and-place equipment.