470 µF, 4 V, 100 mOhm ESR — the bulk tantalum for low-voltage rails
The TPSD477M004R0100: It belongs to KYOCERA AVX's TPS series, a general-purpose line for surface-mount designs that need stable capacitance over temperature and bias voltage. The 100 mOhm ESR is the parameter that governs AC ripple current handling and self-heating — for a 470 µF part at 4 V, this ESR keeps the ripple current capability in the range of several amps at 100 kHz, which suits it for output filtering on low-voltage DC-DC converters or as a bulk decoupling cap near a processor core rail. Operating from -55°C to 125°C, it covers the full industrial temperature envelope and reaches into the under-hood automotive band without a derating step — the molded case and solid tantalum construction maintain stable parameters across that range.
D-case 2917 footprint and supply-chain posture
For designs that need tighter capacitance tolerance, a polymer tantalum or MLCC alternative would be required.