L7818 18 V Linear Regulator

{
  "schema_version": 1,
  "type": "component",
  "slug": "l7818",
  "title": "L7818 18 V Linear Regulator",
  "brief": "Fixed 18 V positive-voltage linear regulator, up to 1.5 A, in the L78xx (7800) series.",
  "version": "0.1.0",
  "license": "CC-BY-SA-4.0",
  "tags": [
    "regulator",
    "linear",
    "fixed",
    "positive",
    "pmic",
    "st",
    "to-220"
  ],
  "component": {
    "mpn": "L7818",
    "manufacturer": "STMicroelectronics",
    "package": "TO-220",
    "pin_count": 3,
    "category": "Power Management",
    "subcategory": "Linear Regulator (LDO)",
    "datasheet": "https://www.st.com/resource/en/datasheet/l78.pdf",
    "parts": {
      "symbol": "l7818.kicad_sym",
      "footprint": "l7818.kicad_mod",
      "model_3d": "l7818-etched.glb",
      "model_3d_plain": "l7818.glb",
      "model_3d_step": "l7818-etched.step",
      "model_3d_step_plain": "l7818.step",
      "lbr": "l7818.lbr"
    },
    "distributor_links": {},
    "pins": [
      {
        "number": "1",
        "name": "INPUT",
        "type": "power_in",
        "description": "Unregulated DC input supply. Absolute maximum V_I = 35 V for V_O ≤ 18 V variants. A 0.33 µF ceramic bypass to GND is recommended close to the pin for stability when the regulator is far from the bulk filter capacitor."
      },
      {
        "number": "2",
        "name": "GROUND",
        "type": "power_in",
        "description": "Common ground reference for both input and output. In TO-220 and TO-220FP this pin is electrically connected to the mounting tab. Return currents for both C_I and C_O bypass capacitors should tie to this pin with a short, low-impedance path."
      },
      {
        "number": "3",
        "name": "OUTPUT",
        "type": "power_out",
        "description": "Regulated +18 V output (2 % tolerance on A-version parts). Delivers up to 1.5 A with adequate heatsinking; internally current-limited and SOA-protected. A 0.1 µF ceramic output capacitor is recommended to improve transient response."
      }
    ],
    "provenance": {
      "extractor": "ds2sf",
      "datasheet": {
        "url": "https://www.st.com/resource/en/datasheet/l78.pdf",
        "pages": 55,
        "sha256": "ccba643d1b7ced87",
        "source_tier": "mfr"
      },
      "cad": "KiCad official (CC-BY-SA 4.0)",
      "pins": {
        "total": 3,
        "described": 3,
        "cites_pages": true,
        "refuses_to_fabricate": true
      }
    },
    "viewers": {
      "symbol": "viewers/symbol.html",
      "footprint": "viewers/footprint.html"
    },
    "models_3d": [
      {
        "file": "l7818.step",
        "role": "plain",
        "up": "Z",
        "units": "mm",
        "origin": "footprint origin = pad-pattern centre",
        "seat": "body on z = 0, through-hole leads below",
        "extents_mm": [
          10.25,
          4.455,
          28.525
        ],
        "zmin_mm": -9.75,
        "centre_offset_mm": 0.932,
        "footprint_binding": "identity",
        "sha256": "7cb065d935df5771f0ba6e48ddd180863a121af76483dad7f18e667a7b68204a",
        "checked": "2026-10-07",
        "checked_by": "factory/step_pose.py (Z-up, origin, seat, binding)"
      },
      {
        "file": "l7818-etched.step",
        "role": "eda",
        "up": "Z",
        "units": "mm",
        "origin": "footprint origin = pad-pattern centre",
        "seat": "body on z = 0, through-hole leads below",
        "extents_mm": [
          10.25,
          4.455,
          28.525
        ],
        "zmin_mm": -9.75,
        "centre_offset_mm": 0.932,
        "footprint_binding": "identity",
        "sha256": "afedf3c2b7b3aee7b139220f197cd6a90c803de1609dfc9c027baa1523144f26",
        "checked": "2026-10-07",
        "checked_by": "factory/step_pose.py (Z-up, origin, seat, binding)"
      }
    ]
  },
  "metadata": {
    "specs": {
      "Type": "Fixed positive linear regulator",
      "Output voltage": "18 V",
      "Output current": "Up to 1.5 A (with heatsink)",
      "Dropout voltage": "2 V typ",
      "Package": "TO-220 (3-lead)",
      "Operating temperature": "0 C to 125 C (junction)"
    }
  },
  "sections": [
    "hero",
    "viewers",
    "readme",
    "breadcrumbs",
    "info"
  ],
  "discovery_triggers": [
    "18V regulator",
    "7800 series",
    "fixed voltage regulator",
    "linear regulator"
  ],
  "discovery_pitch": "A fixed 18 V three-terminal regulator that needs only input and output capacitors, the L78xx workhorse.",
  "author": {
    "name": "Ray",
    "email": "[email protected]"
  },
  "dependencies": {},
  "hero": {
    "type": "image",
    "path": "docs/hero.png"
  },
  "files": [
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    "README.md",
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    "l7818.glb",
    "l7818.step",
    "l7818.lbr",
    "docs/hero.png",
    "docs/l7818-datasheet.pdf",
    "viewers/symbol.html",
    "viewers/footprint.html",
    "l7818-etched.step"
  ],
  "variants": [
    {
      "mpn": "L7818CV",
      "kind": "unknown"
    },
    {
      "mpn": "L7818CP",
      "kind": "unknown"
    },
    {
      "mpn": "L7818CD2T",
      "kind": "unknown"
    },
    {
      "mpn": "L7818D2T",
      "kind": "unknown"
    },
    {
      "mpn": "L7818CDT",
      "kind": "unknown"
    },
    {
      "mpn": "L7818DT",
      "kind": "unknown"
    }
  ]
}