The LM2576 series of regulators are monolithic integrated circuits that provide all the active functions for a step-down (buck) switching regulator, capable of driving 3A load with excellent line and load regulation. These devices are available in fixed output voltages of 3.3V, 5V, 12V, 15V, and an adjustable output version. Requiring a minimum number of external components, these regulators are simple to use and include internal frequency compensation and a fixed-frequency oscillator. The LM2576 series offers a high-efficiency replacement for popular three-terminal linear regulators. It substantially reduces the size of the heat sink, and in some cases no heat sink is required. A standard series of inductors optimized for use with the LM2576 are available from several different manufacturers. This feature greatly simplifies the design of switch-mode power supplies. Other features include a guaranteed ±4% tolerance on output voltage within specified input voltages and output load conditions, and ±10% on the oscillator frequency. External shutdown is included, featuring 50 µA (typical) standby current. The output switch includes cycle-by-cycle current limiting, as well as thermal shutdown for full protection under fault conditions.
The LM2576 series are monolithic integrated circuits that deliver a high‑efficiency 3 A step‑down (buck) regulator. They require only four external components and include internal frequency compensation, a fixed‑frequency 52 kHz oscillator, and built‑in shutdown and thermal protection.
The device is offered in fixed output versions of 3.3 V, 5 V, 12 V, 15 V and an adjustable version, with a wide input voltage range of 40 V (up to 60 V for the HV version). Typical efficiency reaches 75 % at 12 V input and 3 A load.
| Output voltage options | 3.3 V, 5 V, 12 V, 15 V, adjustable |
|---|---|
| Fixed switching frequency | 52 kHz |
| Maximum output current | 3 A |
| Input voltage range | 40 V – 60 V (HV version) |
| Standby current (shutdown) | ≈50 µA typical |
| External components required | 4 |
The regulator uses a 52 kHz fixed‑frequency internal oscillator.
Only four external components are required.
The device is guaranteed to deliver up to 3 A of output current.
The standby current is about 50 µA (typical).