UC3845BM

{
  "schema_version": 1,
  "type": "component",
  "slug": "uc3845bm",
  "title": "UC3845BM",
  "brief": "HGSEMI 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)",
    "uc3845bm",
    "factory-2.0.0",
    "extractor-text"
  ],
  "component": {
    "mpn": "UC3845BM",
    "manufacturer": "HGSEMI",
    "package": "SOP-8",
    "pin_count": 8,
    "category": "Power Management (PMIC)",
    "subcategory": "AC-DC Controllers And Regulators",
    "datasheet": "https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8590456093773099008",
    "parts": {
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      "lbr": "uc3845bm.lbr"
    },
    "distributor_links": {
      "lcsc": "C2987354"
    },
    "distributor_check": {
      "checked_at": "2026-10-18T14:16:33Z",
      "source": "Component Ocean /api/assign-pns",
      "digikey": {
        "pn": null,
        "status": "quota"
      },
      "mouser": {
        "pn": null,
        "status": "quota"
      }
    },
    "pins": [
      {
        "number": "1",
        "name": "COMP",
        "type": "output",
        "description": "This pin is the Error Amplifier output and is made for loop compensation, with an absolute maximum error amplifier output sink current (ISINK(E.A)) of 10 mA."
      },
      {
        "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, with a specified input voltage (VI(E.A)) of 2.42 V to 2.58 V (2.5 V typ) at Vpin1 = 2.5 V."
      },
      {
        "number": "3",
        "name": "ISENSE",
        "type": "input",
        "description": "A voltage proportional to inductor current is connected to this input, which the PWM uses to terminate the output switch conduction; analog inputs (pins 2, 3) are rated from -0.3 V to 5.5 V, with a maximum input signal (VI(MAX)) of 0.9 V to 1.1 V (1.0 V typ)."
      },
      {
        "number": "4",
        "name": "RT/CT",
        "type": "passive",
        "description": "The oscillator frequency and maximum output duty cycle are programmed by connecting resistor RT to Vref and capacitor CT to ground."
      },
      {
        "number": "5",
        "name": "GROUND",
        "type": "power_in",
        "description": "This pin 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."
      },
      {
        "number": "7",
        "name": "VCC",
        "type": "power_in",
        "description": "This pin is the positive supply of the integrated circuit, with an absolute maximum supply voltage of 30 V from a low impedance source."
      },
      {
        "number": "8",
        "name": "Vref",
        "type": "power_out",
        "description": "This is the reference output that provides charging current for capacitor CT through resistor RT, specified at 4.9 V to 5.1 V (5.0 V typ) at TJ = 25°C and IREF = 1 mA."
      }
    ],
    "provenance": {
      "extractor": "extract_pins 0.3",
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        "consensus": "agreed",
        "guards": "pin_guards 0.1: passed",
        "guard_notes": [
          "extractor flagged: The MPN UC3845BM corresponds to the ordering code UC3845BM/TR (SOP8, reel 2500/reel) in the datashee; Pin 1 (COMP) type set to output and pin 4 (RT/CT) set to passive based on the datasheet's descriptio"
        ],
        "pages_sent": 11,
        "cost_usd": 0.0384,
        "at": "2026-10-18T14:14:12"
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        "sha256": "27376c62601f1c47",
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        "total": 8,
        "described": 8,
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        "refuses_to_fabricate": true
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        "extents_mm": [
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        "zmin_mm": 0,
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  "metadata": {
    "specs": {
      "Manufacturer": "HGSEMI",
      "Package": "SOP-8",
      "Category": "Power Management (PMIC)",
      "Pins": "8"
    },
    "characteristics": {
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          "name": "Reference Output Voltage",
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          "min": 4.9,
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          "name": "Line Regulation",
          "symbol": "ΔVREF",
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          "max": 20,
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          "conditions": "TA = 25°C",
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          "max": 57,
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          "name": "Error Amplifier Input Bias Current",
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          "kind": "electrical",
          "unit": "µA",
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          "conditions": "VFB=3V",
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        {
          "name": "Open Loop Voltage Gain",
          "symbol": "AVOL",
          "kind": "electrical",
          "unit": "dB",
          "min": null,
          "typ": 65,
          "max": 90,
          "conditions": "2V ≤ V0 ≤ 4V",
          "source_page": 3,
          "source": "datasheet"
        },
        {
          "name": "Unity Gain Bandwidth",
          "symbol": "UGBW",
          "kind": "electrical",
          "unit": "MHz",
          "min": null,
          "typ": 0.5,
          "max": 0.6,
          "conditions": "Tj=25°C, Note 3",
          "source_page": 3,
          "source": "datasheet"
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        {
          "name": "Power Supply Rejection Ratio",
          "symbol": "PSRR",
          "kind": "electrical",
          "unit": "dB",
          "min": null,
          "typ": 60,
          "max": 70,
          "conditions": "12V ≤ VCC ≤ 25 V",
          "source_page": 3,
          "source": "datasheet"
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        {
          "name": "Output Sink Current",
          "symbol": "ISINK",
          "kind": "electrical",
          "unit": "mA",
          "min": null,
          "typ": 2,
          "max": 7,
          "conditions": "Vpin2 = 2.7V, Vpin1 = 1.1V",
          "source_page": 3,
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        {
          "name": "Output Source Current",
          "symbol": "ISOURCE",
          "kind": "electrical",
          "unit": "mA",
          "min": null,
          "typ": -0.5,
          "max": -1,
          "conditions": "Vpin2 = 2.3V, Vpin1 = 5V",
          "source_page": 3,
          "source": "datasheet"
        },
        {
          "name": "Error Amplifier High Output Voltage",
          "symbol": "VOH",
          "kind": "electrical",
          "unit": "V",
          "min": null,
          "typ": 5,
          "max": 6,
          "conditions": "Vpin2 = 2.3V, RL = 15KΩ to GND",
          "source_page": 3,
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        {
          "name": "Error Amplifier Low Output Voltage",
          "symbol": "VOL",
          "kind": "electrical",
          "unit": "V",
          "min": null,
          "typ": 0.8,
          "max": 1.1,
          "conditions": "Vpin2 = 2.7V, RL = 15KΩ to PIN 8",
          "source_page": 3,
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          "name": "Current Sense Gain",
          "symbol": "GV",
          "kind": "electrical",
          "unit": "V/V",
          "min": 2.85,
          "typ": 3,
          "max": 3.15,
          "conditions": "Note 1 & 2",
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          "name": "Maximum Input Signal",
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          "kind": "electrical",
          "unit": "V",
          "min": 0.9,
          "typ": 1,
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          "conditions": "Vpin1 = 5V (Note 1)",
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          "name": "Current Sense Input Bias Current",
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          "kind": "electrical",
          "unit": "µA",
          "min": null,
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          "conditions": "Vpin3 = 3V",
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          "name": "Output Low Voltage",
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          "kind": "electrical",
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          "min": null,
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          "conditions": "ISINK = 20 mA",
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          "name": "Output Low Voltage",
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          "name": "Output High Voltage",
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          "min": null,
          "typ": 13,
          "max": 13.5,
          "conditions": "ISINK = 20 mA",
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          "name": "Output High Voltage",
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          "conditions": "ISINK = 200 mA",
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        {
          "name": "Rise Time",
          "symbol": "tR",
          "kind": "timing",
          "unit": "nS",
          "min": null,
          "typ": 45,
          "max": 150,
          "conditions": "TJ = 25°C, CL = 1nF (Note 3)",
          "source_page": 3,
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        {
          "name": "Fall Time",
          "symbol": "tF",
          "kind": "timing",
          "unit": "nS",
          "min": null,
          "typ": 35,
          "max": 150,
          "conditions": "TJ = 25°C, CL = 1nF (Note 3)",
          "source_page": 3,
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        {
          "name": "Start Threshold Voltage",
          "symbol": "VTH(ST)",
          "kind": "electrical",
          "unit": "V",
          "min": 7.8,
          "typ": 8.4,
          "max": 9,
          "conditions": "UC3843B,UC3845B",
          "source_page": 3,
          "source": "datasheet"
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        {
          "name": "Minimum Operating Voltage (After Turn On)",
          "symbol": "VOPR(min)",
          "kind": "electrical",
          "unit": "V",
          "min": 7,
          "typ": 7.6,
          "max": 8.2,
          "conditions": "UC3843B,UC3845B",
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        {
          "name": "Maximum Duty Cycle",
          "symbol": "D(MAX)",
          "kind": "electrical",
          "unit": "%",
          "min": 47,
          "typ": 48,
          "max": 50,
          "conditions": "UC3844B,UC3845B",
          "source_page": 3,
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        {
          "name": "Minimum Duty Cycle",
          "symbol": "",
          "kind": "electrical",
          "unit": "",
          "min": 0,
          "typ": null,
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          "conditions": "",
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        {
          "name": "Start-Up Current",
          "symbol": "IST",
          "kind": "electrical",
          "unit": "mA",
          "min": null,
          "typ": 0.17,
          "max": 0.3,
          "conditions": "UC3842B/43B/44B/45B",
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        {
          "name": "Operating Supply Current",
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          "kind": "electrical",
          "unit": "mA",
          "min": null,
          "typ": 13,
          "max": 17,
          "conditions": "Vpin3 = Vpin2 = 0V",
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          "name": "Zener Voltage",
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        {
          "name": "Supply Voltage (low impedance source)",
          "symbol": "VCC",
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          "min": null,
          "typ": null,
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          "conditions": "",
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        {
          "name": "Output Current",
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          "kind": "absolute_maximum",
          "unit": "A",
          "min": -1,
          "typ": null,
          "max": 1,
          "conditions": "",
          "source_page": 2,
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          "name": "Input Voltage (Analog Inputs pins 2,3)",
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          "unit": "V",
          "min": -0.3,
          "typ": null,
          "max": 5.5,
          "conditions": "",
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          "name": "Error Amp Output Sink Current",
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          "max": 10,
          "conditions": "",
          "source_page": 2,
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          "name": "Power Dissipation",
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          "unit": "°C",
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          "max": 260,
          "conditions": "soldering 5 sec.",
          "source_page": 2,
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          "name": "Operating Ambient Temperature",
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          "kind": "recommended_operating",
          "unit": "°C",
          "min": -40,
          "typ": null,
          "max": 85,
          "conditions": "characterized for operation",
          "source_page": 1,
          "source": "datasheet"
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