The TPSW686M006R0250: The 250 mOhm ESR is the number that matters most on a power rail — it limits the ripple current the part can handle before self-heating becomes a problem.
Active production — no LTB to plan for
The product status is Active. This part is still a standard production item through KYOCERA AVX, so it can be specified into a BOM without obsolescence risk for the foreseeable future.
What the 250 mOhm ESR buys you
A 250 mOhm ESR at 100 kHz is the typical value for a 68 µF tantalum in this case size. It means the capacitor can handle a ripple current of roughly 0.7 A RMS at 85°C before the internal temperature rise exceeds the derating curve. Below that, the self-heating stays inside the package limits. This ESR is low enough for output filtering on a switching regulator but not so low that inrush current becomes a problem — a good middle ground for general-purpose bulk decoupling.
Case size and board fit
That is a low-profile part — it fits under a 2 mm board-to-board clearance. The W case code is standard across the TPS family, so the footprint is shared with other capacitance values in the same voltage range.
Temperature range and derating
Rated for -55°C to +125°C. At the high end, the DC bias derating is already baked into the ±20% tolerance — a 68 µF cap at 6.3 V and 125°C will still measure above 54 µF. No voltage derating below 85°C; above that, KYOCERA AVX recommends 50% derating on the applied voltage.