Bulk cap for tight-regulation rails
The TPMD108K004R0025: 1000 µF at 4 V with 25 mOhm ESR — this is a high-ripple-current tantalum for point-of-load decoupling where the voltage rail is 3.3 V or lower and the load draws fast transients (cite:,). The 25 mOhm ESR keeps the ripple voltage under 25 mV at 1 A ripple current; a standard 100 mOhm tantalum would show 100 mV of ripple on the same rail (cite:).
This cap sits on a satellite EPS bus or an avionics power supply where the ambient cycles from cold-soak to internal heat rise without derating (cite:).