component

LM2576 3A Step-Down Regulator

Public Unreviewed

by Ray

3 A step-down (buck) switching regulator with a 52 kHz internal oscillator and few external parts.

buckregulatorswitchingstep-downpmictito-263
Overview Files Discover Packages Releases Dependencies Issues Breadcrumbs Pull Requests Activity

3D Model

Open in new tab ↗

Symbol & Footprint

Schematic Symbol

Open full view ↗

PCB Footprint

Open full view ↗
Contents

README

markdown

LM2576

Texas Instruments · Switching Regulator (Buck) · TO-263-5

The LM2576 is a 3 A step-down (buck) switching regulator from the Simple Switcher family. It integrates the switch, oscillator (52 kHz), and control loop, so a working supply needs only an external inductor, catch diode, and capacitors. This 5 V fixed-output version drives loads up to 3 A from inputs to 40 V.

Pinout

Pin Name Type Function
1 VIN power_in Supply input pin to the collector of the internal high-side power transistor. Connect to the unregulated DC input (7 V to 40 V for LM2576; up to 60 V for LM2576HV). Path from VIN to the high-frequency bypass CIN and GND must be as short as possible.
2 OUTPUT output Emitter pin of the internal power transistor - the switching node of the buck converter. Attach this pin to the inductor and to the cathode of the external freewheeling (catch) diode.
3 GND power_in Device ground reference. Return path for CIN must be as short as possible for stable switching operation.
4 FEEDBACK input Feedback sense input. On the ADJ version, connect to the midpoint of the external resistor divider to set VOUT (VREF = 1.23 V). On fixed-output versions (3.3/5/12/15 V), connect this pin directly to the output capacitor.
5 ~{ON}/OFF input Active-low enable input for the regulator. HIGH = OFF (shutdown, ~50 uA typical standby); LOW = ON. Tie to GND to permanently enable the regulator. Do not leave floating. Input voltage range -0.3 V to +VIN.

Key specifications

Parameter Value
Type Buck (step-down) switching regulator
Output current 3 A
Output voltage 5 V fixed (this version)
Input voltage Up to 40 V
Switching frequency 52 kHz typ
Efficiency 77% typ
Line/load regulation Internally compensated
Operating temperature -40 C to 125 C (junction)

Ordering variants

Same part, different packaging or reel option.

  • LM2576KC
  • LM2576KTT
  • LM2576KTTR

CAD (KiCad official)

  • Symbol: lm2576.kicad_sym
  • Footprint: lm2576.kicad_mod
  • 3D model: TO-263-5 (D2PAK) surface-mount tab body from KiCad Package_TO_SOT_SMD/TO-263-5_TabPin3.

Provenance

Data extracted from the manufacturer datasheet, not a distributor listing:

  • Datasheet: Texas Instruments datasheet (45 pp, sha256 ed17313084806fc0, retrieved 2026-08-17, tier: manufacturer)
  • Extractor: ds2sf (Claude). Every pin and dimension is cited to a datasheet page; it refuses to fabricate.
  • CAD: KiCad official libraries (CC-BY-SA 4.0).

Datasheet PDF