3A buck regulator with 28V input ceiling
The TPS54331DR is a non-synchronous step-down buck converter from Texas Instruments' Eco-Mode™ series, delivering up to 3A continuous output from a 3.5V to 28V input rail. The adjustable output voltage range starts at 0.8V and goes up to 25V, making it suitable for 3.3V, 5V, or 12V intermediate buses in industrial and automotive-adjacent designs.
8-SOIC package and layout notes
Housed in an 8-SOIC package (0.154" width, 3.90mm body), the TPS54331DR is a surface-mount device that requires no exposed pad — the junction-to-ambient thermal resistance is managed through the copper pour on the board. For a 3A output at high input-to-output differential, ensure the PCB has sufficient copper area on the drain-connected pins (pins 6-8) to dissipate heat. The non-synchronous topology means an external Schottky diode is needed; the 570kHz switching frequency allows a 10µH to 22µH inductor in the typical application.