LM2576 PDF – Buck Converter Regulator

Part number : LM2576, LM2576HV

Functions : 40V, 3A Low Component Count Step-Down Regulator

Package information : TO-220-4 Pin, DDPAK / TO-263 Type

Manufacturer : National Semiconductor, Texas Instruments


LM2576 Buck Converter


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.


LM2576 pinout datasheet



1. 3.3V, 5V, 12V, 15V, and adjustable output versions
2. Adjustable version output voltage range, 1.23V to 37V (57V for HV version) ±4% max over line and load conditions
3. Guaranteed 3A output current
4. Wide input voltage range, 40V up to 60V for HV version
5. Requires only 4 external components
6. 52 kHz fixed frequency internal oscillator
7. TTL shutdown capability, low power standby mode
8. High efficiency
9. Uses readily available standard inductors
10. Thermal shutdown and current limit protection
11. P+ Product Enhancement tested

Block Diagram

LM2576 block diagram


1. Simple high-efficiency step-down (buck) regulator
2. Efficient pre-regulator for linear regulators
3. On-card switching regulators
4. Positive to negative converter (Buck-Boost)


LM2576 application

Official Homepage

1. http://www.ti.com/product/LM2576

2. http://www.onsemi.com/PowerSolutions/product.do?id=LM2576


LM2576 Datasheet PDF