LM2576 Application Note

●3.0 A, 15 V, Step−Down Switching Regulator

●The LM2576 series of regulators are monolithic integrated circuits ideally suited for easy and convenient design of a step−down switching regulator (buck converter). All circuits of this series are capable of driving a 3.0 A load with excellent line and load regulation. These devices are available in fixed output voltages of 3.3 V, 5.0 V, 12 V, 15 V, and an adjustable output version.

●These regulators were designed to minimize the number of external components to simplify the power supply design. Standard series of inductors optimized for use with the LM2576 are offered by several different inductor manufacturers.

●Features

●•3.3 V, 5.0 V, 12 V, 15 V, and Adjustable Output Versions

●•Adjustable Version Output Voltage Range, 1.23 to 37 V ±4% Maximum Over Line and Load Conditions

●•Guaranteed 3.0 A Output Current

●•Wide Input Voltage Range

●•Requires Only 4 External Components

●•52 kHz Fixed Frequency Internal Oscillator

●•TTL Shutdown Capability, Low Power Standby Mode

●•High Efficiency

●•Uses Readily Available Standard Inductors

●•Thermal Shutdown and Current Limit Protection

●•Moisture Sensitivity Level (MSL) Equals 1

●•Pb−Free Packages are Available

●Applications

●•Simple High−Efficiency Step−Down (Buck) Regulator

●•Efficient Pre−Regulator for Linear Regulators

●•On−Card Switching Regulators

●•Positive to Negative Converter (Buck−Boost)

●•Negative Step−Up Converters

●•Power Supply for Battery Chargers