Capacitance, voltage, and ESR — the three numbers that matter
The TAJA225K016H is a 2.2 µF, 16 V rated molded tantalum capacitor from the KYOCERA AVX TAJ series, in a 1206 (3216 Metric) surface-mount package. The ±10% tolerance keeps the actual capacitance within 1.98 µF to 2.42 µF — tight enough for decoupling and timing circuits where a ±20% part would risk marginal behaviour. The 6.5 Ohm ESR at 25°C sets the ripple current ceiling: for a 100 kHz ripple with 100 mA RMS, the internal dissipation is I²R = 65 mW, which at 125°C ambient leaves little margin before the part self-heats above the rated limit. A lower-ESR size code (B or C) would handle higher ripple without derating.
Temperature grade and deployment fit
The 125°C upper limit is the absolute maximum ambient; at that temperature the voltage derating curve (per the TAJ series datasheet) typically recommends applying no more than 2/3 of the rated voltage for reliable operation.
No official second-source or cross-reference in the TAJ series — the same case size and rating from Kemet or Vishay would be a functional equivalent but not a guaranteed drop-in (ESR and ripple current ratings differ).