680 µF bulk cap for 2.5 V rails
The TAJD687M002RNJ: This is a 680 µF molded tantalum capacitor rated at 2.5 V with a 200 mOhm ESR — the combination tells you it is meant for bulk decoupling on a low-voltage rail where ripple current and transient response matter. The 200 mOhm ESR keeps self-heating under control at moderate ripple, but it is not a low-ESR part; if the rail sees high-frequency switching noise, pair it with a ceramic cap to shunt the higher harmonics.
Rated from -55 to 125 °C, this cap lives comfortably in avionics, satellite, downhole instrumentation, or outdoor industrial gear that sees both arctic cold and engine-bay heat. The molded case handles the thermal cycling better than a conformal-coated chip — less risk of cracking the dielectric at the extremes.