The TPSC686M006R0150 is a 68 µF molded tantalum capacitor from the KYOCERA AVX TPS series, rated at 6.3 V with a ±20% tolerance.
The molded case provides mechanical stability across the thermal cycle. For a 125°C hot spot, the 6.3 V rating leaves margin for derating.
The TPS series is a broad production family, so second-source equivalents from Kemet or Vishay exist in the same 2312 case size and 68 µF/6.3 V rating — but the 150 mOhm ESR is specific to this order code; a substitute with higher ESR may not meet the ripple current requirement.