3A step-down in a 3x2 mm VQFN
The TPS628132MQWRWYRQ1 is a Texas Instruments automotive-grade synchronous buck regulator delivering 3A continuous output from a 2.75V to 6V input rail, with a fixed 1.8V output. The 1.8MHz to 4MHz switching frequency range lets you shrink the inductor to a 2.2 µH or 1 µH footprint, which matters when the ECU board real estate is already consumed by the microcontroller and transceivers. The 9-VQFN-HR (3x2) package with wettable flank gives the production line an AOI-visible solder joint — no x-ray required for post-reflow inspection.
Thermal and switching trade-offs
The synchronous rectifier (integrated low-side FET) keeps efficiency above 90% at moderate loads, but at full 3A the power dissipation in the 3x2 mm package demands a solid thermal via pattern under the exposed pad — a four-layer board with 1 oz copper on the inner planes is the typical starting point. The 1.8V fixed output eliminates the feedback resistor divider, saving two external components and one potential noise injection point.