BC557

{
  "slug": "bc557",
  "version": "0.1.0",
  "type": "component",
  "description": "Changjiang Electronics Tech (CJ) Bipolar Transistors - BJT, TO-92. Pinout cross-checked by two models against the datasheet, KiCad symbol/footprint/3D.",
  "tags": [
    "component",
    "transistors",
    "bc557",
    "factory-2.0.0",
    "extractor-text"
  ],
  "dependencies": {},
  "hero": {
    "type": "image",
    "path": "docs/hero.png"
  },
  "files": [
    "page.json",
    "README.md",
    "bc557.kicad_sym",
    "bc557.kicad_mod",
    "bc557.glb",
    "bc557.step",
    "bc557.lbr",
    "docs/hero.png",
    "docs/bc557-datasheet.pdf",
    "viewers/symbol.html",
    "viewers/footprint.html",
    "bc557-hero.glb",
    "bc557-hero.overlay.json",
    "bc557-etched.glb"
  ],
  "component": {
    "mpn": "BC557",
    "manufacturer": "Changjiang Electronics Tech (CJ)",
    "package": "TO-92",
    "pin_count": 3,
    "category": "Transistors",
    "subcategory": "Bipolar Transistors - BJT",
    "datasheet": "https://datasheet.lcsc.com/datasheet/pdf/c5a89ac139894070aea54d4115b40d9a.pdf",
    "parts": {
      "symbol": "bc557.kicad_sym",
      "footprint": "bc557.kicad_mod",
      "model_3d": "bc557-hero.glb",
      "model_3d_plain": "bc557-etched.glb",
      "model_3d_step": "bc557-etched.step",
      "model_3d_step_plain": "bc557.step",
      "lbr": "bc557.lbr"
    },
    "distributor_links": {
      "lcsc": "C180418"
    },
    "distributor_check": {
      "checked_at": "2026-10-22T21:50:08Z",
      "source": "Component Ocean /api/assign-pns",
      "digikey": {
        "pn": null,
        "status": "quota"
      },
      "mouser": {
        "pn": null,
        "status": "quota"
      }
    },
    "pins": [
      {
        "number": "1",
        "name": "COLLECTOR",
        "type": "passive",
        "description": "Collector of the PNP transistor; BC557 VCEO is -45 V, VCBO is -50 V and continuous collector current is -0.1 A."
      },
      {
        "number": "2",
        "name": "BASE",
        "type": "passive",
        "description": "Base of the PNP transistor; BC557 emitter-base voltage limit VEBO is -5 V."
      },
      {
        "number": "3",
        "name": "EMITTER",
        "type": "passive",
        "description": "Emitter of the PNP transistor; total device power dissipation is 625 mW at Ta=25°C."
      }
    ],
    "provenance": {
      "extractor": "extract_pins 0.3",
      "factory_chain": {
        "factory": "2.0.0",
        "extractor": "extract_pins 0.3",
        "primary_model": "claude-sonnet-5-5",
        "primary_mode": "text",
        "consensus_model": "claude-sonnet-5-5",
        "consensus": "agreed",
        "guards": "pin_guards 0.1: passed",
        "guard_notes": [],
        "pages_sent": 4,
        "cost_usd": 0.0284,
        "at": "2026-10-22T21:49:53"
      },
      "datasheet": {
        "url": "https://datasheet.lcsc.com/datasheet/pdf/c5a89ac139894070aea54d4115b40d9a.pdf",
        "pages": 4,
        "sha256": "81775b75ec2ea3df",
        "source_tier": "lcsc"
      },
      "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": [
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        "file": "bc557.step",
        "role": "plain",
        "up": "Z",
        "units": "mm",
        "origin": "footprint origin = pad-pattern centre",
        "seat": "body on z = 0, through-hole leads below",
        "extents_mm": [
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        "zmin_mm": -2.5,
        "centre_offset_mm": 0.542,
        "footprint_binding": "identity",
        "sha256": "f0b61c32ecbf0067157adc5a3d4966ceadf5d6dafe93c51af35f76c41c71a54a",
        "checked": "2026-10-22",
        "checked_by": "factory/step_pose.py (Z-up, origin, seat, binding)"
      },
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        "file": "bc557-etched.step",
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      }
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  }
}