CD431

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  "slug": "cd431",
  "title": "CD431",
  "brief": "Changjing Voltage Reference, SOT-23. Pinout extracted from the datasheet, KiCad symbol/footprint/3D.",
  "version": "0.2.0",
  "license": "CC-BY-SA-4.0",
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    "pmic",
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  "component": {
    "mpn": "CD431",
    "manufacturer": "Changjing",
    "package": "SOT-23",
    "pin_count": 3,
    "category": "PMIC",
    "subcategory": "Voltage Reference",
    "datasheet": "https://datasheet.lcsc.com/datasheet/pdf/6d683a055a364e369dbbdbf23d40135e.pdf",
    "parts": {
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      "lbr": "cd431.lbr"
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    "distributor_links": {},
    "pins": [
      {
        "number": "1",
        "name": "CATHODE",
        "type": "passive",
        "description": "Cathode (K). Sinks the regulating current; VKA is regulated to a value set by the external divider between cathode, reference, and anode. Absolute max VKA=36V, IKA continuous range -100 to +150mA, minimum cathode current for regulation 0.45-1.0mA."
      },
      {
        "number": "2",
        "name": "REFERENCE",
        "type": "input",
        "description": "Reference input (R). Internal amplifier compares this pin against the internal 2.5V bandgap (Vref typ 2.5V, 2.475-2.525V) and adjusts cathode current to hold VREF equal to Vref. Reference input current typ 1.5µA (max 4µA)."
      },
      {
        "number": "3",
        "name": "ANODE",
        "type": "passive",
        "description": "Anode (A). Common/ground return for the shunt regulator; the divider that programs VKA references this pin."
      }
    ],
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      "cad": "KiCad official (CC-BY-SA 4.0)",
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        "described": 3,
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        "refuses_to_fabricate": true
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    "pin1": {
      "pad": "1",
      "at": [
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        -0.95
      ],
      "corner": "top-left",
      "source": "silk-marker",
      "derived_from": "SOT-23@sha256:0d88c86c1b6d8c1a",
      "mark": "drawn"
    },
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  "metadata": {
    "specs": {
      "Manufacturer": "Changjing",
      "Package": "SOT-23",
      "Category": "PMIC",
      "Pins": "3"
    },
    "characteristics": {
      "version": 1,
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        {
          "name": "Reference input voltage",
          "symbol": "Vref",
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          "unit": "V",
          "min": 2.475,
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          "max": 2.525,
          "conditions": "VKA=VREF, IKA=10mA",
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        {
          "name": "Deviation of reference input voltage over temperature",
          "symbol": "△Vref/△T",
          "kind": "electrical",
          "unit": "mV",
          "min": null,
          "typ": 4.5,
          "max": 17,
          "conditions": "VKA=VREF, IKA=10mA; TMIN=-25℃, TMAX=+85℃ (note)",
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        {
          "name": "Ratio of change in reference input voltage to change in cathode voltage (VKA = 10V to VREF)",
          "symbol": "△Vref/△VKA",
          "kind": "electrical",
          "unit": "mV/V",
          "min": null,
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          "max": -2.7,
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        {
          "name": "Ratio of change in reference input voltage to change in cathode voltage (VKA = 36V to 10V)",
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          "kind": "electrical",
          "unit": "mV/V",
          "min": null,
          "typ": -0.5,
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          "name": "Reference input current",
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        {
          "name": "Deviation of reference input current over full temperature range",
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        },
        {
          "name": "Minimum cathode current for regulation",
          "symbol": "IKA(min)",
          "kind": "electrical",
          "unit": "mA",
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          "typ": 0.45,
          "max": 1,
          "conditions": "VKA=VREF",
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        },
        {
          "name": "Off-state cathode current",
          "symbol": "IKA(OFF)",
          "kind": "electrical",
          "unit": "μA",
          "min": null,
          "typ": 0.05,
          "max": 0.5,
          "conditions": "VKA=36V, VREF=0",
          "source_page": 1,
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        },
        {
          "name": "Dynamic impedance",
          "symbol": "ZKA",
          "kind": "electrical",
          "unit": "Ω",
          "min": null,
          "typ": 0.15,
          "max": 0.5,
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          "name": "Cathode voltage",
          "symbol": "VKA",
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          "max": 36,
          "conditions": "",
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          "name": "Cathode current range (continuous)",
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        {
          "name": "Reference input current range",
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        },
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          "name": "Junction temperature",
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          "typ": null,
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          "conditions": "TMIN≤Ta≤TMAX, TA=-25 to 85℃",
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        {
          "name": "Thermal resistance from junction to ambient",
          "symbol": "RθJA",
          "kind": "thermal",
          "unit": "℃/W",
          "min": null,
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  "updated_at": "2026-09-24T18:50:25.605Z"
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