The TPS62151RGTR is a Texas Instruments synchronous step-down (buck) regulator from the DCS-Control family. It delivers a fixed 1.8V output at up to 1A from an input range of 3V to 17V, switching at 2.5MHz. The fixed output voltage eliminates the external feedback divider, which saves two resistors and one feedback-node capacitor from the BOM — useful when the 1.8V rail is the only low-voltage rail on the board and board space is tight.
Sizing the 1A rail — load budget and thermal margin
The 1A output rating is the continuous current limit. For a rail feeding a small FPGA core or a set of MCU I/O banks, budget the total load at no more than 800 mA to keep junction temperature rise within the 85°C ambient ceiling. The 2.5MHz switching frequency lets the output inductor and capacitor shrink — a 2.2 µH to 4.7 µH inductor in the 0805 or 1210 footprint works, and the output cap can be a single 22 µF ceramic.