15 µF, 25 V, 1 Ohm ESR — tantalum MnO₂ derating rule
The TAJY156M025RNJ: The manganese dioxide cathode system means the standard derating practice is 50% of rated voltage for reliable operation in low-impedance circuits — apply this part at 12.5 V or below to stay inside the safe operating area.
ESR and ripple current — what the 1 Ohm spec limits
At 1 Ohm, the ESR is on the higher side for a 2917 case-size tantalum. This directly limits the ripple current the capacitor can handle without exceeding its internal temperature rise — for a 25 V part in a buck converter output filter, the ripple current should be kept below ~500 mA RMS to avoid self-heating that accelerates failure.
Temperature range and capacitance stability
Tantalum MnO₂ capacitors lose capacitance at low temperature — at -55°C the capacitance can drop to 60-70% of the 25°C value, and the ESR rises by a factor of 3-5x. At 125°C, the leakage current increases and the voltage derating should be increased to 60% of rated voltage (15 V max) for long-term reliability.
It remains in the KYOCERA AVX production portfolio and is sourced through authorized distribution.
Package and footprint — 2917 (7343 Metric), Y case code
The Y code indicates the 7343-20 profile — 2.0 mm max height, compatible with the common 7343-20 footprint.