LM2575,LM2576: Series SIMPLE SWITCHER® 3-A Step-Down Voltage Regulator

LM2575,LM2576: Series SIMPLE SWITCHER® 3-A Step-Down Voltage Regulator

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.
Straight Leads 5-Lead TO-220 Package LM2575T-XX or LM2575HVT-XX
DDPAK/TO-263 Package 5-Lead Surface-Mount Package LM2575S-XX or LM2575HVS-XX

 

Features

  • 3.3-V, 5-V, 12-V, 15-V, and Adjustable Output Versions
  • Adjustable Version Output Voltage Range,1.23 V to 37 V (57 V for HV Version) ±4% Maximum Over Line and Load Conditions
  • Specified 3-A Output Current
  • Wide Input Voltage Range: 40 V Up to 60 V for HV Version
  • 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
  • Create a Custom Design with WEBENCH Tools
  • Thermal Shutdown and Current Limit Protection
  • P+ Product Enhancement Tested

Applications

  • Simple High-Efficiency Step-Down (Buck) Regulator
  • Efficient Pre-regulator for Linear Regulators
  • On-Card Switching Regulators
  • Positive-to-Negative Converter (Buck-Boost)