DESCRIPTION

· The LM2576 series provides all active functions for a step-down switching regulator.
· Available in fixed (3.3V, 5V, 12V) and adjustable (1.23V to 37V) output versions.
· Capable of driving a 3A load with excellent line and load regulation.
· Requires minimal external components and includes internal frequency compensation.
· Offers high efficiency, reducing heat sink size or eliminating it in many cases.
· Uses standard inductors, simplifying switch-mode power supply design.
· Features external shutdown with standby current less than 200µA.
· Includes cycle-by-cycle current limiting and thermal shutdown for protection.

FEATURES

· 3.3V, 5V, 12V, and adjustable output versions.
· Fixed version: ±3% max. output voltage; Adjustable version: ±2% max. feedback voltage.
· Guaranteed 3A output current.
· Wide input voltage range: 4V to 40V.
· Wide output voltage range: 1.23V to 37V.
· Requires only 4 external components.
· 52kHz fixed frequency internal oscillator.
· Low power standby mode with IQ typically < 200 µA.
· Efficiency typically > 80%.
· Uses readily available standard inductors.
· Thermal shutdown and current limit protection.
· 100% electrical thermal limit burn-in.

APPLICATIONS

· Simple high-efficiency step-down (buck) regulator.
· Efficient pre-regulator for linear regulators.
· On-card switching regulators.
· Positive to negative converter (inverting Buck-Boost).
· Isolated Flyback Converter with minimal external components.
· Negative Boost Converter.