UC3845BD

{
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  "type": "component",
  "slug": "uc3845bd",
  "title": "UC3845BD",
  "brief": "lingxingic AC-DC Controllers And Regulators, SOP-8. Pinout cross-checked by two models against the datasheet, KiCad symbol/footprint/3D.",
  "version": "0.1.0",
  "license": "CC-BY-SA-4.0",
  "tags": [
    "component",
    "power management (pmic)",
    "uc3845bd",
    "factory-2.0.0",
    "extractor-text"
  ],
  "component": {
    "mpn": "UC3845BD",
    "manufacturer": "lingxingic",
    "package": "SOP-8",
    "pin_count": 8,
    "category": "Power Management (PMIC)",
    "subcategory": "AC-DC Controllers And Regulators",
    "datasheet": "https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8603345531880431616",
    "parts": {
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      "lbr": "uc3845bd.lbr"
    },
    "distributor_links": {
      "lcsc": "C22397225"
    },
    "distributor_check": {
      "checked_at": "2026-10-18T12:45:41Z",
      "source": "Component Ocean /api/assign-pns",
      "digikey": {
        "pn": null,
        "status": "quota"
      },
      "mouser": {
        "pn": null,
        "status": "quota"
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    },
    "pins": [
      {
        "number": "1",
        "name": "COMP",
        "type": "output",
        "description": "This is the error amplifier output, made available for loop compensation; the datasheet states the error amplifier output sink current is limited to 10 mA absolute maximum."
      },
      {
        "number": "2",
        "name": "VFB",
        "type": "input",
        "description": "This is the inverting input of the error amplifier, normally connected to the switching power supply output through a resistor divider; the analog inputs are rated -0.3 V to +6.3 V."
      },
      {
        "number": "3",
        "name": "ISENSE",
        "type": "input",
        "description": "A voltage proportional to inductor current is applied here and the PWM uses it to terminate output switch conduction; the current-sense maximum input signal is 1 V typical (0.9 V to 1.1 V)."
      },
      {
        "number": "4",
        "name": "RT/CT",
        "type": "passive",
        "description": "Resistor RT to VREF and capacitor CT to ground set the oscillator frequency and maximum output duty cycle, with operation to 500 kHz possible."
      },
      {
        "number": "5",
        "name": "GROUND",
        "type": "power_in",
        "description": "This is the combined control circuitry and power ground."
      },
      {
        "number": "6",
        "name": "OUTPUT",
        "type": "output",
        "description": "This output directly drives the gate of a power MOSFET, sourcing and sinking peak currents up to 1 A; the absolute maximum output current is ±1 A."
      },
      {
        "number": "7",
        "name": "Vi",
        "type": "power_in",
        "description": "This is the positive supply of the control IC; the absolute maximum supply voltage is 30 V from a low impedance source."
      },
      {
        "number": "8",
        "name": "VREF",
        "type": "power_out",
        "description": "This is the reference output, specified at 5.00 V typical (4.90 V to 5.10 V at Io = 1 mA), and it provides charging current for CT through RT."
      }
    ],
    "provenance": {
      "extractor": "extract_pins 0.3",
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        "consensus": "agreed",
        "guards": "pin_guards 0.1: passed",
        "guard_notes": [
          "extractor flagged: The SOP-8 package drawing (section 5.2, page 8) is image-only in the extracted text, so the SOP-8 pi; The datasheet covers the whole UC384X family; the UC3845 is the 8.8 V on / 7.6 V off UVLO and 50% ma; RT/CT is typed as passive because the datasheet describes it as a resistor and capacitor timing node",
          "1/8 pin names appear NOWHERE in the datasheet text: ['5:GROUND@p3']"
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        "at": "2026-10-18T12:44:58"
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  "metadata": {
    "specs": {
      "Manufacturer": "lingxingic",
      "Package": "SOP-8",
      "Category": "Power Management (PMIC)",
      "Pins": "8"
    },
    "characteristics": {
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        {
          "name": "power dissipation",
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        {
          "name": "line regulation",
          "symbol": "ΔVREF",
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          "min": null,
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          "name": "load regulation",
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          "name": "total output variation",
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        {
          "name": "output short circuit current",
          "symbol": "ISC",
          "kind": "electrical",
          "unit": "mA",
          "min": -30,
          "typ": -100,
          "max": -180,
          "conditions": "",
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        {
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          "max": 55,
          "conditions": "Tj=25℃",
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          "name": "oscillator frequency over temperature range",
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          "kind": "electrical",
          "unit": "kHz",
          "min": 48,
          "typ": null,
          "max": 56,
          "conditions": "Tamb=Tlow to Thigh, Tj=25℃",
          "source_page": 4,
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        },
        {
          "name": "oscillator frequency (RT/CT test point)",
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          "kind": "electrical",
          "unit": "kHz",
          "min": 225,
          "typ": 250,
          "max": 275,
          "conditions": "Tj=25℃, RT=6.2kΩ, CT=1nF",
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        {
          "name": "discharge current",
          "symbol": "Idischg",
          "kind": "electrical",
          "unit": "mA",
          "min": 7.8,
          "typ": 8.3,
          "max": 8.8,
          "conditions": "VOSC=2V, Tj=25℃, Tamb=-40 to 85℃",
          "source_page": 4,
          "source": "datasheet"
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          "name": "error amplifier input voltage",
          "symbol": "V2",
          "kind": "electrical",
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          "min": 2.42,
          "typ": 2.5,
          "max": 2.58,
          "conditions": "VPIN1=2.5V",
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          "source": "datasheet"
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          "name": "input bias current",
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          "kind": "electrical",
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          "typ": -0.1,
          "max": -2,
          "conditions": "VFB=5V",
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        {
          "name": "error amplifier open-loop gain",
          "symbol": "AVOL",
          "kind": "electrical",
          "unit": "dB",
          "min": 65,
          "typ": 90,
          "max": null,
          "conditions": "2V≤Vo≤4V",
          "source_page": 4,
          "source": "datasheet"
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        {
          "name": "unity gain bandwidth",
          "symbol": "BW",
          "kind": "electrical",
          "unit": "MHz",
          "min": 0.7,
          "typ": 1,
          "max": null,
          "conditions": "Tj=25℃",
          "source_page": 4,
          "source": "datasheet"
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        {
          "name": "power supply rejection ratio",
          "symbol": "PSRR",
          "kind": "electrical",
          "unit": "dB",
          "min": 60,
          "typ": 70,
          "max": null,
          "conditions": "12V≤Vi≤25V",
          "source_page": 5,
          "source": "datasheet"
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        {
          "name": "error amplifier output sink current",
          "symbol": "IO",
          "kind": "electrical",
          "unit": "mA",
          "min": 2,
          "typ": 12,
          "max": null,
          "conditions": "VPIN2=2.7V, VPIN1=1.1V",
          "source_page": 5,
          "source": "datasheet"
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        {
          "name": "error amplifier output source current",
          "symbol": "IO",
          "kind": "electrical",
          "unit": "mA",
          "min": -0.5,
          "typ": -1,
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          "conditions": "VPIN2=2.3V, VPIN1=5V",
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        {
          "name": "VOUT high",
          "symbol": "VOUT High",
          "kind": "electrical",
          "unit": "V",
          "min": 5,
          "typ": 6.2,
          "max": null,
          "conditions": "VPIN2=2.3V; RL=15KΩ to ground",
          "source_page": 5,
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        {
          "name": "VOUT low",
          "symbol": "VOUT Low",
          "kind": "electrical",
          "unit": "V",
          "min": null,
          "typ": 0.8,
          "max": 1.1,
          "conditions": "VPIN2=2.7V; RL=15KΩ to PIN 8",
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        {
          "name": "current sense gain",
          "symbol": "GV",
          "kind": "electrical",
          "unit": "V/V",
          "min": 2.85,
          "typ": 3,
          "max": 3.15,
          "conditions": "",
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        {
          "name": "maximum input signal",
          "symbol": "V3",
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          "min": 0.9,
          "typ": 1,
          "max": 1.1,
          "conditions": "VPIN1=5V",
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          "name": "current sense supply voltage rejection",
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          "name": "current sense input bias current",
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          "typ": -2,
          "max": -10,
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          "name": "delay to output",
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          "max": 300,
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          "name": "output low level (20mA)",
          "symbol": "VOL",
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          "unit": "V",
          "min": null,
          "typ": 0.1,
          "max": 0.4,
          "conditions": "Isink=20mA",
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        {
          "name": "output low level (200mA)",
          "symbol": "VOL",
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          "symbol": "VOH",
          "kind": "electrical",
          "unit": "V",
          "min": 12,
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          "max": null,
          "conditions": "Isource=200mA",
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          "name": "UVLO saturation",
          "symbol": "VOLS",
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          "max": 1.1,
          "conditions": "Vi=6V, ISINK=1mA",
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          "name": "output rise time",
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          "max": 150,
          "conditions": "CL=1nF",
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          "max": 150,
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          "name": "UVLO start threshold (UC3843/5)",
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          "kind": "electrical",
          "unit": "V",
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          "typ": 8.8,
          "max": 9.4,
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          "name": "UVLO minimum operating voltage after turn-on (UC3843/5)",
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          "name": "maximum duty cycle (UC3844/5)",
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          "kind": "electrical",
          "unit": "%",
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          "name": "minimum duty cycle",
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          "min": null,
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          "max": 0,
          "conditions": "",
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          "kind": "electrical",
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          "name": "operating supply current",
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          "kind": "electrical",
          "unit": "mA",
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          "typ": 12,
          "max": 20,
          "conditions": "VPIN2=VPIN3=0V",
          "source_page": 5,
          "source": "datasheet"
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          "name": "zener voltage",
          "symbol": "Viz",
          "kind": "electrical",
          "unit": "V",
          "min": 30,
          "typ": 36,
          "max": null,
          "conditions": "Ii=25mA",
          "source_page": 5,
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