BC857B

{
  "slug": "bc857b",
  "version": "0.1.0",
  "type": "component",
  "description": "Slkor SLKORMICRO Elec Bipolar (BJT), SOT-23. Pinout cross-checked by two models against the datasheet, KiCad symbol/footprint/3D.",
  "tags": [
    "component",
    "transistors-thyristors",
    "bc857b",
    "factory-2.0.0",
    "extractor-text"
  ],
  "dependencies": {},
  "hero": {
    "type": "image",
    "path": "docs/hero.png"
  },
  "files": [
    "page.json",
    "README.md",
    "bc857b.kicad_sym",
    "bc857b.kicad_mod",
    "bc857b.glb",
    "bc857b.step",
    "bc857b.lbr",
    "docs/hero.png",
    "docs/bc857b-datasheet.pdf",
    "viewers/symbol.html",
    "viewers/footprint.html",
    "bc857b-hero.glb",
    "bc857b-hero.overlay.json"
  ],
  "component": {
    "mpn": "BC857B",
    "manufacturer": "Slkor SLKORMICRO Elec",
    "package": "SOT-23",
    "pin_count": 3,
    "category": "Transistors/Thyristors",
    "subcategory": "Bipolar (BJT)",
    "datasheet": "https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8588885188210266112",
    "parts": {
      "symbol": "bc857b.kicad_sym",
      "footprint": "bc857b.kicad_mod",
      "model_3d": "bc857b-hero.glb",
      "model_3d_plain": "bc857b.glb",
      "model_3d_step": "bc857b-etched.step",
      "model_3d_step_plain": "bc857b.step",
      "lbr": "bc857b.lbr"
    },
    "distributor_links": {
      "lcsc": "C556165",
      "digikey": "4878-BC857BTR-ND",
      "mouser": "637-BC857B"
    },
    "distributor_check": {
      "checked_at": "2026-10-09T00:13:33Z",
      "source": "Component Ocean /api/assign-pns",
      "digikey": {
        "pn": "4878-BC857BTR-ND",
        "status": "found",
        "lifecycle": "Active"
      },
      "mouser": {
        "pn": "637-BC857B",
        "status": "found"
      }
    },
    "pins": [
      {
        "number": "1",
        "name": "BASE",
        "type": "input",
        "description": "Base terminal of the PNP transistor, driven with IB (saturation test at IC = -100 mA, IB = -5 mA gives VBE(sat) of -1.1 V max)."
      },
      {
        "number": "2",
        "name": "EMITTER",
        "type": "passive",
        "description": "Emitter terminal of the PNP transistor; the datasheet limits emitter-base voltage to VEBO = -5 V and continuous collector current to -0.1 A."
      },
      {
        "number": "3",
        "name": "COLLECTOR",
        "type": "passive",
        "description": "Collector terminal of the PNP transistor; for the BC857 the datasheet gives VCBO = -50 V and VCEO = -45 V maximum ratings, with collector current limited to -0.1 A continuous."
      }
    ],
    "provenance": {
      "extractor": "extract_pins 0.3",
      "factory_chain": {
        "factory": "2.0.0",
        "extractor": "extract_pins 0.3",
        "primary_model": "claude-haiku-5-5",
        "primary_mode": "text",
        "consensus_model": "claude-sonnet-5-5",
        "consensus": "agreed",
        "guards": "pin_guards 0.1: passed",
        "guard_notes": [
          "extractor flagged: The datasheet is a family datasheet covering BC856, BC857 and BC858 in SOT-23. It does not have a se; The datasheet gives no pin-level electrical limits. Pin descriptions use the family maximum ratings ; Pin types are KiCad ERC classes inferred for a bipolar transistor (base as input, emitter and collec"
        ],
        "pages_sent": 4,
        "cost_usd": 0.0258,
        "at": "2026-10-09T00:12:45"
      },
      "datasheet": {
        "url": "https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8588885188210266112",
        "pages": 4,
        "sha256": "b27e6044426e3c60",
        "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": [
      {
        "file": "bc857b.step",
        "role": "plain",
        "up": "Z",
        "units": "mm",
        "origin": "footprint origin = pad-pattern centre",
        "seat": "z = 0",
        "extents_mm": [
          2.5,
          3.0,
          1.2
        ],
        "zmin_mm": 0.0,
        "centre_offset_mm": 0.0,
        "footprint_binding": "identity",
        "sha256": "dd5d1711204e1d8d26cd11490923bd84340820baa69538c385a4300ec2539bc0",
        "checked": "2026-10-09",
        "checked_by": "factory/step_pose.py (Z-up, origin, seat, binding)"
      },
      {
        "file": "bc857b-etched.step",
        "role": "eda",
        "up": "Z",
        "units": "mm",
        "origin": "footprint origin = pad-pattern centre",
        "seat": "z = 0",
        "extents_mm": [
          2.5,
          3.0,
          1.2
        ],
        "zmin_mm": 0.0,
        "centre_offset_mm": 0.0,
        "footprint_binding": "identity",
        "sha256": "8655b70704bb178a37fc29a537f1c26bcfb66ad5bf8609310207a31e47032b24",
        "checked": "2026-10-09",
        "checked_by": "factory/step_pose.py (Z-up, origin, seat, binding)"
      }
    ]
  }
}