# LM2576 buck regulator: 3 A, up to 40 V in

> A classic 3 A step-down switching regulator: fixed and adjustable outputs, input limit, 52 kHz switching and the parts it needs.

Canonical: https://roboticsengineering.in/components/lm2576-buck-regulator/ | Published: 2026-11-03 | Updated: 2026-11-03

**The LM2576 is a 3 A step-down (buck) switching regulator in 3.3 V, 5 V, 12 V, 15 V and adjustable versions, with a 52 kHz fixed oscillator, a 40 V input (60 V for the HV version) and ±4 percent output tolerance.** It replaces a hot linear regulator with a cooler one, and needs only four external components. Figures are from the Texas Instruments LM2576 datasheet.

## Key specifications

| Output current | 3 A |
| --- | --- |
| Outputs | 3.3, 5, 12, 15 V, adjustable 1.23–37 V |
| Input | up to 40 V (60 V HV) |
| Switching | 52 kHz |
| Standby | 50 µA typ |
| Protection | current limit, thermal shutdown |

## What the datasheet promises

| Item | Datasheet value |
| --- | --- |
| Output current | 3 A specified |
| Fixed outputs | 3.3 V, 5 V, 12 V, 15 V |
| Adjustable output | 1.23 V to 37 V (57 V for the HV version), ±4 percent maximum over line and load |
| Input voltage | Up to 40 V; up to 60 V for the HV version |
| Switching frequency | 52 kHz fixed, ±10 percent |
| Standby current | 50 µA typical with the shutdown pin used |
| Protection | Cycle-by-cycle current limit and thermal shutdown |
| External parts | Four components (input and output capacitors, diode, inductor) |
| Package | TO-220 (5 pin), among others |

The datasheet marks the LM2576 as an older design and lists newer converters, such as the LMR51430 and the LM76003, for new products. The LM2576 stays useful because it is common on cheap modules and because its 52 kHz switching is easy to filter.

## Using it on a robot

- Use a Schottky catch diode and an inductor from the datasheet’s selection guide; a wrong diode or inductor is the usual reason for overheating.
- Place a bulk capacitor on the input, because motors on the same battery cause voltage dips.
- Set an adjustable module with a meter and no load before connecting a servo or controller.
- For a similar small module see the [LM2596](https://roboticsengineering.in/components/lm2596-buck-converter/); for a linear alternative at low current see the [LM317](https://roboticsengineering.in/components/lm317-adjustable-regulator/).

## Sources and further reading

- [Texas Instruments LM2576 datasheet](https://www.ti.com/lit/ds/symlink/lm2576.pdf) — the outputs, current, input range and frequency above.

Last reviewed: November 2026. Limits are from the Texas Instruments datasheet; modules sold with this chip vary. No price is quoted because it has not been checked.