BC857ALT1G

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  "type": "component",
  "slug": "bc857alt1g",
  "title": "BC857ALT1G",
  "brief": "onsemi Bipolar (BJT), SOT-23. Pinout cross-checked by two models against the datasheet, KiCad symbol/footprint/3D.",
  "version": "0.1.0",
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  "component": {
    "mpn": "BC857ALT1G",
    "manufacturer": "onsemi",
    "package": "SOT-23",
    "pin_count": 3,
    "category": "Transistors/Thyristors",
    "subcategory": "Bipolar (BJT)",
    "datasheet": "https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8586189655683710976",
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      "lbr": "bc857alt1g.lbr"
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    "distributor_links": {
      "lcsc": "C163726",
      "digikey": "BC857ALT1GOSTR-ND",
      "mouser": "863-BC857ALT1G"
    },
    "distributor_check": {
      "checked_at": "2026-10-09T18:21:31Z",
      "source": "Component Ocean /api/assign-pns",
      "digikey": {
        "pn": "BC857ALT1GOSTR-ND",
        "status": "found",
        "lifecycle": "Active"
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        "pn": "863-BC857ALT1G",
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      }
    },
    "pins": [
      {
        "number": "1",
        "name": "BASE",
        "type": "input",
        "description": "Base terminal of the PNP transistor; the datasheet gives VCE(sat) test conditions at IB = −0.5 mA (IC = −10 mA) and IB = −5.0 mA (IC = −100 mA), and the emitter-base breakdown voltage V(BR)EBO is −5.0 V minimum."
      },
      {
        "number": "2",
        "name": "EMITTER",
        "type": "passive",
        "description": "Emitter terminal of the PNP transistor; the emitter-base voltage is rated VEBO −5.0 V, with the continuous collector current limited to −100 mA and peak to −200 mA."
      },
      {
        "number": "3",
        "name": "COLLECTOR",
        "type": "passive",
        "description": "Collector terminal of the BC857 PNP transistor; the collector-emitter voltage is rated VCEO −45 V and collector-base voltage VCBO −50 V."
      }
    ],
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        "guards": "pin_guards 0.1: passed",
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        "at": "2026-10-09T18:19:08"
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  "metadata": {
    "specs": {
      "Manufacturer": "onsemi",
      "Package": "SOT-23",
      "Category": "Transistors/Thyristors",
      "Pins": "3"
    },
    "characteristics": {
      "version": 1,
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      "rows": [
        {
          "name": "Collector-Emitter Breakdown Voltage (BC857 series)",
          "symbol": "V(BR)CEO",
          "kind": "electrical",
          "unit": "V",
          "min": -45,
          "typ": null,
          "max": null,
          "conditions": "IC = -10 mA",
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        },
        {
          "name": "Collector-Emitter Breakdown Voltage (BC857A)",
          "symbol": "V(BR)CES",
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          "name": "Collector-Base Breakdown Voltage (BC857 series)",
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          "conditions": "IC = -10 µA (as printed: IC = -10 A)",
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          "max": null,
          "conditions": "IE = -1.0 µA (as printed: IE = -1.0 A)",
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        },
        {
          "name": "Collector Cutoff Current",
          "symbol": "ICBO",
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          "max": -15,
          "conditions": "VCB = -30 V",
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          "name": "Collector Cutoff Current",
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          "conditions": "VCB = -30 V, TA = 150°C",
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        {
          "name": "Collector-Emitter Saturation Voltage",
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          "name": "Collector-Emitter Saturation Voltage",
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          "max": -0.65,
          "conditions": "IC = -100 mA, IB = -5.0 mA",
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        {
          "name": "Base-Emitter Saturation Voltage",
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          "max": -0.7,
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          "name": "Base-Emitter Saturation Voltage",
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          "kind": "electrical",
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          "typ": null,
          "max": -0.9,
          "conditions": "IC = -100 mA, IB = -5.0 mA",
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        {
          "name": "Base-Emitter On Voltage",
          "symbol": "VBE(on)",
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          "unit": "V",
          "min": -0.6,
          "typ": null,
          "max": -0.75,
          "conditions": "IC = -2.0 mA, VCE = -5.0 V",
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          "name": "Base-Emitter On Voltage",
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          "max": -0.82,
          "conditions": "IC = -10 mA, VCE = -5.0 V",
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        {
          "name": "Current-Gain - Bandwidth Product",
          "symbol": "fT",
          "kind": "electrical",
          "unit": "MHz",
          "min": 100,
          "typ": null,
          "max": null,
          "conditions": "IC = -10 mA, VCE = -5.0 Vdc, f = 100 MHz",
          "source_page": 2,
          "source": "datasheet"
        },
        {
          "name": "Output Capacitance",
          "symbol": "Cob",
          "kind": "electrical",
          "unit": "pF",
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          "max": 4.5,
          "conditions": "VCB = -10 V, f = 1.0 MHz",
          "source_page": 2,
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        {
          "name": "Noise Figure (BC857 series)",
          "symbol": "NF",
          "kind": "electrical",
          "unit": "dB",
          "min": null,
          "typ": null,
          "max": 10,
          "conditions": "IC = -0.2 mA, VCE = -5.0 Vdc, RS = 2.0 k, f = 1.0 kHz, BW = 200 Hz",
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        },
        {
          "name": "Collector-Emitter Voltage (BC857 series)",
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          "max": -45,
          "conditions": "Maximum Ratings, TA = 25°C",
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        },
        {
          "name": "Collector-Base Voltage (BC857 series)",
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          "conditions": "Maximum Ratings, TA = 25°C",
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        {
          "name": "Emitter-Base Voltage",
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          "max": -5,
          "conditions": "Maximum Ratings, TA = 25°C",
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        {
          "name": "Collector Current - Continuous",
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          "unit": "mAdc",
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          "max": -100,
          "conditions": "Maximum Ratings, TA = 25°C",
          "source_page": 1,
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        {
          "name": "Collector Current - Peak",
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        {
          "name": "Junction and Storage Temperature",
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          "unit": "°C",
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          "typ": null,
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          "conditions": "",
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          "name": "Total Device Dissipation, FR-5 Board",
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          "unit": "mW",
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          "source_page": 1,
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          "name": "Derate above 25°C, FR-5 Board",
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          "kind": "thermal",
          "unit": "mW/°C",
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        {
          "name": "Thermal Resistance, Junction-to-Ambient, FR-5 Board",
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        {
          "name": "Total Device Dissipation, Alumina Substrate",
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          "name": "Thermal Resistance, Junction-to-Ambient (transient-response note)",
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          "conditions": "Figure 14 SOA note: RJA = 200°C/W MAX",
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