The TAJC475K050TNJ: Rated 4.7 µF at 50 VDC — this is the working voltage, not the surge rating. For a 50 V rail, the derating guideline for solid tantalum is 20 % on voltage, so a 50 V part on a 40 V rail leaves margin against the dielectric breakdown risk that shows up on power-up transients.
Availability confirmed at RFQ.
