The LM2576/LM2576HV 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 versions. 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/LM2576HV 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 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 50µA
(typical) standby current. The output switch includes cycle-by-cycle
current limiting, as well as thermal shutdown for full protection under
fault conditions.