Capacitance, voltage, and temperature range
The TAJC105K050HNJ: This is a 1 µF tantalum capacitor rated at 50 V, ±10% tolerance, in the molded TAJ series from KYOCERA AVX. The 50 V rating gives headroom for 12 V, 24 V, and even 48 V rails — the derating rule for solid tantalums (typically 50% of rated voltage for reliability) still leaves 25 V working, which covers most industrial bus voltages. At 125°C the leakage current rises, but the capacitance stays within the ±10% tolerance window.
ESR and ripple current — the trade-off
The 5.5 Ohm ESR is typical for a small-case tantalum at this voltage and capacitance. Compared to an MLCC of the same value, this ESR is roughly 10× higher — meaning the tantalum will run warmer for the same ripple current. For a power-supply output filter drawing 100 mA ripple, the I²R loss is 55 mW, which is manageable in the 2312 case. But if the application needs low output ripple at high frequency, an MLCC in parallel is the usual fix.
The 2312 (6032 Metric) case measures 6.00 mm x 3.20 mm with a seated height of 2.80 mm max. The manufacturer size code is C. This is a surface-mount part — the footprint matches the standard tantalum 2312 land pattern. The molded body gives good mechanical strength for reflow soldering, but the part is moisture-sensitive; bake per J-STD-033 if the floor life is exceeded.