10 µF, 6.3 V rated — ESR drives the thermal budget
TAJS106M006SNJ is a 10 µF molded tantalum capacitor from the KYOCERA AVX TAJ series, rated at 6.3 V with a tolerance of ±20%. The 4 Ohm ESR is the spec that sets the ripple-current ceiling — at 10 µF and 6.3 V, the self-heating from ripple current through 4 Ohm limits the AC load the part can handle without derating. In a 1206 package, the ESR is higher than larger case codes in the TAJ family; for a low-impedance rail, a lower-ESR part in a larger case (e.g., TAJ D case) would be a better fit.
Military temp range in a small SMD footprint
The 1206 (3216 Metric) package measures 3.20 mm x 1.60 mm with a seated height of 1.20 mm, fitting tight PCB layouts in multi-layer boards.