The TAJD687M004SNJ: 680 µF at 4 V rated — this is a bulk capacitance choice for low-voltage rails, typically a 3.3 V or 2.5 V supply where the ripple current demands a low-ESR tantalum.
ESR and high-temperature endurance
500 mOhm ESR at 100 kHz — this sets the self-heating under ripple current; a 1 A ripple dissipates 0.5 W, which at 125°C ambient reduces the 2000-hour lifetime. The 2000 hours at 125°C rating means the capacitor is qualified for continuous operation at that temperature, not just survival — relevant for engine-bay or downhole electronics where ambient exceeds 105°C.
The 2917 (7343 Metric) case size (7.30 mm x 4.30 mm, 3.10 mm seated height) is a standard footprint for bulk tantalum capacitors; the D-size code matches common PCB land patterns for 680 µF parts.