3.0A, 52kHz, Step-Down Switching Regulator

LM2576

FEATURES

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

Adjustable Version Output Voltage Range, 1.23 to 37V

+/- 4% AG10Maximum Over Line and Load Conditions

Guaranteed 3.0A Output Current

Wide Input Voltage Range

Requires Only 4 External Components

52kHz 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 3

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

DESCRIPTION

ORDERING INFORMATION

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 3.0A load

with excellent line and load regulation. These devices are

available in fixed output voltages of 3.3V, 5.0V,12V, 15V,

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.

Since the LM2576 converter is a switch-mode power supply, its efficiency is significantly higher in

comparison with popular three-terminal linear regulators, especially with higher input voltages.

available from several different manufacturers. This feature greatly simplifies the design of

switch-mode power supplies. The LM2576 features include a guaranteed +/- 4% tolerance

on output voltage within specified input voltages and output load conditions, and +/-10% on the

oscillator frequency (+/- 2% over 0oC to 125 oC).

External shutdown is included, featuring 80 ㎂(typical) standby current. The output switch includes

cycle-bycycle current limiting, as well as thermal shutdown for full protection under fault conditions.

2008 - Ver. 1.0

HTC

- 1 -

Device

Marking

Package

LM2576T-X.X

LM2576T-X.X

TO-220

In many cases, the power dissipated is so low that no heatsink is required or its size could

be reduced dramatically. A standard series of inductors optimized for use with the LM2576 are

LM2576TV-X.X

LM2576T-X.X

LM2576R

LM2576R-X.X

TO-263

TO-220V

1. Vin 2. Output

3. Ground

4. Feedback 5. On/Off

1

5

1

5

1

5

TO-220 PKG

TO-263 PKG

TO-220V PKG