ESR and the decoupling budget
The TPSB106K025R1800: The 1.8 Ohm ESR at 25 °C sets the ripple-current ceiling — for a 100 kHz switching regulator output, the capacitor's self-heating rises with Iripple² × ESR. A lower-ESR tantalum in the same B case code would handle more ripple before hitting the 125 °C temperature limit, but this part's ESR is adequate for general-purpose bulk decoupling on a 25 V rail where ripple is under 100 mA RMS.
Temperature range and storage
This covers avionics bay, outdoor telecom cabinet, and downhole tool environments where the ambient swings past 85 °C. The molded case is not hermetic, so store the reels in dry conditions (RH < 60 %) to avoid moisture ingress that can shift leakage current after reflow.
1411 (3528 Metric) / 1210 case, B code, 3.50 mm x 2.80 mm footprint with a seated height of 2.10 mm max. The 0.110-inch width matches the standard 1210 land pattern — no via-in-pad needed for this two-terminal part.