12 A buck in a 3.5 mm × 3.5 mm footprint
The TI TPS56C231RNNR is a synchronous step-down buck regulator that delivers 12 A continuous output from a 3.8 V to 17 V input rail, adjustable down to 0.6 V and up to 5.5 V. It packs into an 18-VFQFN package — small enough for dense point-of-load boards.
No last-time-buy or obsolescence risk for new designs. No drop-in replacement is listed on the official cross-reference; the closest functional peer from TI is the LMR33630APCQRNXRQ1, but that is a 3 A part in a different package (wettable-flank QFN), not a pin-compatible swap.