What this 6 MHz buck regulator does for your rail
The TPS62621YFFR is a synchronous step-down (buck) converter from Texas Instruments that delivers a fixed 1.8V output at up to 600 mA from an input range of 2.3V to 5.5V. The synchronous rectifier (internal FET for both high-side and low-side) keeps efficiency above 90% over most of the load range, and the fixed 1.8V output means no external resistor divider is needed — just the inductor, input/output caps, and you have a regulated rail.
Package reality: 6-DSBGA and what it means for assembly
The 6-DSBGA package (6 bumps, 0.4 mm pitch, ~0.9 mm × 1.3 mm body) is a wafer-level chip-scale package. It requires a solder-paste stencil with 0.2 mm apertures and a reflow profile that peaks at 260 °C. Hand soldering is not practical — you need a pick-and-place machine and a reflow oven. The small footprint saves board space, but the lack of exposed thermal pad means heat is conducted through the solder bumps and the PCB copper. For 600 mA continuous at 1.8V out from 5V in, the power dissipation is about 1.9 W — keep the copper pour under the package generous and use at least two via-in-pad to the ground plane.
Texas Instruments has not issued a last-time-buy or end-of-life notice for this part as of the latest records.