What the 35 V / 6.8 µF rating buys you on a 24 V rail
The TAJC685K035RNJ: Rated 35 V with 6.8 µF capacitance, this TAJ-series molded tantalum gives 10 V of headroom on a nominal 24 V bus — enough margin to survive a 28 V transient without derating stress. The 1.8 Ohm ESR at 100 kHz sets the ripple current ceiling: at 35 V, the cap can handle roughly 400 mA ripple without exceeding its internal temperature rise. For a buck converter switching at 500 kHz, that ESR also dominates the output ripple voltage — expect about 18 mV ripple per amp of inductor ripple current.
The 2312 (6032 metric) case is a rework-friendly size — 6.00 mm x 3.20 mm with a seated height of 2.80 mm. Under hot air at 260 °C, the part lifts cleanly after about 8 seconds if the board has a thermal relief on the anode pad. The silver-palladium termination wets well with Sn63Pb37 or SAC305; just watch for tombstoning if one pad heats faster than the other. No exposed paddle to worry about — it's a two-terminal part.
The molded case is not hermetically sealed — if the board sees condensing humidity, conformal coat over the cap body is advised to prevent silver migration on the terminations.
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