The TPS54331 is a non-synchronous buck converter with an 80 mΩ internal switch that takes 3.5 to 28 V in and delivers up to 3 A, with the output adjustable down to 0.8 V. It switches at a fixed 570 kHz and has a pulse-skipping Eco-mode for light loads. It is the design-it-yourself step above the LM2596 and LM2576. Figures are from the Texas Instruments datasheet SLVS839H.
Key specifications
| Input | 3.5–28 V |
|---|---|
| Output current | 3 A |
| Output | adjustable down to 0.8 V |
| Switching | 570 kHz fixed |
| Shutdown | 1 µA typical |
| Package | SOIC-8 / SO PowerPAD |
What the datasheet promises
| Item | Datasheet value |
|---|---|
| Input voltage | 3.5 to 28 V |
| Output current | 3 A continuous |
| Output voltage | Adjustable down to 0.8 V |
| Reference voltage | 0.8 V (0.772 to 0.828 V) |
| Switch | Integrated 80 mΩ high-side MOSFET |
| Switching frequency | Fixed 570 kHz |
| Shutdown current | 1 µA typical, 4 µA maximum (EN = 0 V, VIN = 12 V) |
| Control | Current mode with internal slope compensation; adjustable slow start; programmable UVLO |
| Protection | Cycle-by-cycle current limit, frequency foldback, overvoltage transient protection, thermal shutdown (165 °C) |
| Junction temperature | −40 to 150 °C |
| Package | SOIC-8 or SO PowerPAD-8 |
The output voltage is set with a divider from the output to the feedback pin; the output follows from the 0.8 V reference. Because the part is not synchronous it needs an external catch diode, an inductor and ceramic capacitors; the datasheet has the design equations.
Using it on a robot
- Use it for a 12 V or 24 V battery down to 5 V or 3.3 V, where a linear regulator such as the LM7805 would waste too much as heat.
- Keep the switching loop (input capacitor, switch, diode) small and on one side of the board, as the datasheet layout section advises.
- Use the PowerPAD package with a copper area under it if you load it near 3 A.
- Check the ripple on the output with a scope before you power a microcontroller or sensor from it.
Sources and further reading
- Texas Instruments TPS54331 datasheet (SLVS839H) — input range, current, reference, frequency, shutdown current and protection above.
Last reviewed: November 2026. Limits are from the Texas Instruments datasheet; modules built on this chip vary. No price is quoted because it has not been checked.
Where to buy in India
These open a store search. Compare seller, price and reviews before you order.