The TPSB157K004R0250: Rated 150 µF at 4 V, this tantalum provides the energy reservoir for a 3.3 V or 1.8 V rail where a ceramic cap's DC bias derating would eat half the nominal capacitance.
This matters for avionics black boxes that sit unpowered at -55°C on the tarmac and then see 105°C internal ambient in flight. The molded case construction (Type: Molded) provides the mechanical stability for these swings — no conformal-coat cracking risk you'd see with a dipped part.
Package fit — 1411 (3528 Metric) / 1210 land pattern
Listed with both 1411 (3528 Metric) and 1210 case codes — the physical footprint is 3.50 mm x 2.80 mm with a seated height of 2.10 mm max. If your PCB has a 1210 tantalum pad, this part drops in; if it's a 3528 metric pad, same. Confirm the pad geometry against your assembly drawing — the B case code is standard across the TPS series, so any existing TPS B-case footprint works.