LM2596 (adjustable buck)

{
  "schema_version": 1,
  "type": "component",
  "slug": "lm2596-adj",
  "title": "LM2596 (adjustable buck)",
  "brief": "TI 150 kHz 3 A adjustable buck regulator, TO-263. VOUT 1.2-37 V, integrated switch. Datasheet-verified.",
  "version": "0.1.0",
  "license": "CC-BY-SA-4.0",
  "tags": [
    "component",
    "regulator",
    "buck",
    "switching",
    "to-263",
    "texas-instruments"
  ],
  "component": {
    "mpn": "LM2596S-ADJ",
    "manufacturer": "Texas Instruments",
    "package": "TO-263-5 (D2PAK)",
    "pin_count": 5,
    "category": "Power Management",
    "subcategory": "Buck switching regulator",
    "datasheet": "https://www.ti.com/lit/ds/symlink/lm2596.pdf",
    "parts": {
      "symbol": "lm2596-adj.kicad_sym",
      "footprint": "lm2596-adj.kicad_mod",
      "model_3d": "lm2596-adj-etched.glb",
      "model_3d_plain": "lm2596-adj.glb",
      "model_3d_step": "lm2596-adj-etched.step",
      "model_3d_step_plain": "lm2596-adj.step",
      "lbr": "lm2596-adj.lbr"
    },
    "distributor_links": {},
    "pins": [
      {
        "number": "1",
        "name": "VIN",
        "type": "power_in",
        "description": "Positive input supply for the switching regulator, 4.5 V to 40 V operating (45 V absolute max). A low-ESR bypass capacitor must be placed directly at this pin to supply the switch currents and minimize input transients."
      },
      {
        "number": "2",
        "name": "Output",
        "type": "output",
        "description": "Internal high-side switch node (SW). Swings between approximately (VIN - VSAT) and about -0.5 V (catch-diode drop) with duty cycle VOUT/VIN; connect to the external inductor and Schottky catch diode. PCB copper area on this node must be minimized to reduce EMI coupling."
      },
      {
        "number": "3",
        "name": "GND",
        "type": "power_in",
        "description": "Circuit ground and power return for the regulator. On the TO-263 (KTT) package the metal tab is also GND."
      },
      {
        "number": "4",
        "name": "FB",
        "type": "input",
        "description": "Feedback input to the error amplifier, regulated to VREF = 1.23 V (typ) on the -ADJ version. Connect to the R1/R2 external divider from VOUT: VOUT = 1.23 V x (1 + R2/R1). Feedback bias current is typically 10 nA (50 nA max at 25 degC). Absolute-max range -0.3 V to 25 V."
      },
      {
        "number": "5",
        "name": "ON/OFF",
        "type": "input",
        "description": "TTL-compatible active-low shutdown input. Pulling below ~1.3 V (or tying to GND / leaving open) enables the regulator; driving above ~1.3 V (up to 25 V max) shuts it down and drops total supply current to ~80 uA typ. Internally clamped; input current 5 uA typ at VLOGIC = 2.5 V."
      }
    ],
    "provenance": {
      "extractor": "ds2sf",
      "datasheet": {
        "url": "https://www.ti.com/lit/ds/symlink/lm2596.pdf",
        "pages": 47,
        "sha256": "fbd0a8af4dcd4c37",
        "source_tier": "mfr"
      },
      "cad": "KiCad official (CC-BY-SA 4.0)",
      "pins": {
        "total": 5,
        "described": 5,
        "cites_pages": true,
        "refuses_to_fabricate": true
      }
    },
    "viewers": {
      "symbol": "viewers/symbol.html",
      "footprint": "viewers/footprint.html"
    },
    "models_3d": [
      {
        "file": "lm2596-adj-etched.step",
        "role": "eda",
        "up": "Z",
        "units": "mm",
        "origin": "footprint origin = pad-pattern centre",
        "seat": "z = 0",
        "extents_mm": [
          15.0,
          10.0,
          4.42
        ],
        "zmin_mm": 0.0,
        "centre_offset_mm": 0.0,
        "footprint_binding": "identity",
        "sha256": "b7e296a6f62db6da20b096222078c036a481a5b166e03ddb3cbe5bea0c4ef04b",
        "checked": "2026-10-16",
        "checked_by": "factory/step_pose.py (Z-up, origin, seat, binding)"
      }
    ]
  },
  "metadata": {
    "specs": {
      "Type": "Buck (step-down) switching regulator",
      "Switching frequency": "150 kHz (fixed)",
      "Output current": "3 A",
      "Output voltage": "1.2-37 V adjustable (VREF 1.23 V)",
      "Input voltage": "up to 40 V",
      "Control": "TTL-compatible ON/OFF",
      "Protection": "Thermal shutdown + cycle-by-cycle current limit",
      "Package": "TO-263-5 (D2PAK)",
      "Body (L×W×H)": "10.2 × 8.4 × 4.6 mm"
    }
  },
  "sections": [
    "hero",
    "viewers",
    "readme",
    "breadcrumbs",
    "info"
  ],
  "discovery_triggers": [
    "lm2596",
    "3a buck regulator",
    "adjustable step-down converter",
    "lm2596 dc-dc"
  ],
  "discovery_pitch": "LM2596S-ADJ 150 kHz 3 A adjustable buck switching regulator (TO-263) with datasheet-verified pinout, KiCad symbol/footprint/3D, and full provenance.",
  "author": {
    "name": "Ray",
    "email": "[email protected]"
  },
  "dependencies": {},
  "hero": {
    "type": "image",
    "path": "docs/hero.png"
  },
  "files": [
    "page.json",
    "README.md",
    "lm2596-adj.kicad_sym",
    "lm2596-adj.kicad_mod",
    "lm2596-adj.glb",
    "lm2596-adj.step",
    "lm2596-adj.lbr",
    "docs/hero.png",
    "docs/lm2596-adj-datasheet.pdf",
    "viewers/symbol.html",
    "viewers/footprint.html",
    "lm2596-adj-etched.step"
  ],
  "variants": [
    {
      "mpn": "LM2596S-ADJ (TO-263, tape & reel)",
      "kind": "different-part"
    },
    {
      "mpn": "LM2596T-ADJ (TO-220-5)",
      "kind": "different-part"
    }
  ]
}