The TAJD477K006RNJ is a molded tantalum capacitor from the KYOCERA AVX TAJ series, rated 470 µF at 6.3 V with ±10% tolerance. The 400 mOhm ESR is the series resistance that limits ripple current and generates self-heating. For a 470 µF cap at 6.3 V, this ESR is typical for the D case size — not a low-ESR variant, so the ripple current rating is modest. Derate the applied voltage per the manufacturer's guidelines; a 6.3 V cap on a 5 V rail runs at 79 % of rated voltage, within the typical 80 % derating rule for tantalum.
The molded case and tantalum construction hold capacitance stability across this band — expect the ESR to rise at cold temperatures and the leakage to increase above 85°C.