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 3-A load with excellent line and load regulation.
These devices are available in fixed output voltages of 3.3 V, 5 V, 12 V, 15 V, and an
adjustable output version.Requiring a minimum number of external
components, these regulators are simple to use and include fault protection 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 ±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 LM76003
requires very few external components and has a pinout designed for simple, optimum PCB
layout for EMI and thermal performance. See the device comparison table to compare specs.
