220 µF bulk cap for 6.3 V rails
At 125°C the rated voltage derates to 2/3 of the 6.3 V mark, so the rail should stay below 4.2 V at the high end. The 2917 (7343 Metric) case is a standard footprint for 220 µF tantalums; the 1.5 mm seated height keeps it low-profile on a 4-layer board.
