Fixed 3.3V rail, 2A continuous — the BOM-fit regulator
The Texas Instruments TPS6209733RWKT is a synchronous step-down (buck) converter in the iDCS-Control series, delivering a fixed 3.3V output at up to 2A from a 2.5V to 6V input rail.
Rated for 2A continuous output, this part handles a typical 3.3V rail powering an MCU plus a few peripherals — think Cortex-M4 with a radio module or a small FPGA core supply. The 2A ceiling leaves headroom for inrush without hitting current limit. Switching frequency runs between 1.5 MHz and 2.5 MHz, which keeps the inductor physically small — a 1 µH to 2.2 µH shielded inductor in the 0806 or 1008 footprint fits. The higher end of that band pushes switching losses up slightly but shrinks the output capacitor count.
11-VFQFN-HR (2x2) — footprint and thermal reality
The 11-VFQFN-HR package measures 2 mm x 2 mm — a compact land pattern that demands a 4-layer board for the thermal via array under the exposed pad. The centre pad is the primary heat path; without a solid via cluster to the ground plane, the junction temperature climbs fast above 1 A. The junction-to-ambient thermal resistance depends heavily on the PCB copper area — budget a 1-inch-square copper pour on the bottom layer if you plan to run near 2 A at 85°C ambient.