What this TAJ tantalum is and where it sits on the board
The TAJC155K050RNJ: This is a Molded tantalum capacitor from the KYOCERA AVX TAJ series — the workhorse surface-mount solid tantalum for general-purpose decoupling, filtering, and timing circuits on commercial and industrial boards. The 2312 (6032 Metric) case, size code C, is a common footprint that mates with standard tantalum land patterns on two-layer and four-layer boards.
Rated -55 to 125 °C, this cap covers the full military temperature band. That makes it a candidate for avionics, downhole instrumentation, satellite payloads, and outdoor telecom gear where the ambient can swing from a cold soak to a hot enclosure. The molded case and solid tantalum construction hold up to thermal cycling better than wet electrolytics.
Listed as Active by KYOCERA AVX. This is a current-production part — no last-time-buy window, no NRND flag. The TAJ series is widely stocked across multiple distributors, so lead times are typically short for standard values like this one.