UC3845N

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  "type": "component",
  "slug": "uc3845n",
  "title": "UC3845N",
  "brief": "Texas Instruments AC-DC Controllers And Regulators, DIP-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": [
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    "power management (pmic)",
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  "component": {
    "mpn": "UC3845N",
    "manufacturer": "Texas Instruments",
    "package": "DIP-8",
    "pin_count": 8,
    "category": "Power Management (PMIC)",
    "subcategory": "AC-DC Controllers And Regulators",
    "datasheet": "https://www.ti.com/cn/lit/gpn/uc2845",
    "parts": {
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      "footprint": "uc3845n.kicad_mod",
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      "model_3d_step": "uc3845n-etched.step",
      "model_3d_step_plain": "uc3845n.step",
      "lbr": "uc3845n.lbr"
    },
    "distributor_links": {
      "lcsc": "C701467",
      "digikey": "296-11620-5-ND",
      "mouser": "595-UC3845N"
    },
    "distributor_check": {
      "checked_at": "2026-10-10T22:30:39Z",
      "source": "Component Ocean /api/assign-pns",
      "digikey": {
        "pn": "296-11620-5-ND",
        "status": "found",
        "lifecycle": "Active"
      },
      "mouser": {
        "pn": "595-UC3845N",
        "status": "found"
      }
    },
    "pins": [
      {
        "number": "1",
        "name": "COMP",
        "type": "output",
        "description": "Error amplifier compensation pin; external compensation network connects here to shape the error amplifier output, and the amplifier has internal current limiting so COMP can be forced to GROUND externally to set zero duty cycle."
      },
      {
        "number": "2",
        "name": "VFB",
        "type": "input",
        "description": "Inverting input of the internal error amplifier, used to close the voltage feedback loop, with the datasheet noting that VFB lead length and stray capacitance should be kept minimal for stability."
      },
      {
        "number": "3",
        "name": "ISENSE",
        "type": "input",
        "description": "Primary-side current sense input connected to the MOSFET current sense resistor and to the PWM comparator, which terminates OUTPUT conduction; the datasheet gives a typical 1 V peak input and recommends an RC filter against leading-edge spikes."
      },
      {
        "number": "4",
        "name": "RT/CT",
        "type": "bidirectional",
        "description": "Oscillator timing pin, with timing resistor RT connected from VREF and timing capacitor CT to GROUND setting the switching frequency; the datasheet states the timing resistor must never be less than 5 kΩ."
      },
      {
        "number": "5",
        "name": "GROUND",
        "type": "power_in",
        "description": "Analog and power ground return for this 8-pin package (no separate PWRGND pin), which the datasheet recommends keeping separate from high-current gate driver return paths."
      },
      {
        "number": "6",
        "name": "OUTPUT",
        "type": "output",
        "description": "Totem-pole gate driver for the external MOSFET, sourcing and sinking peak currents up to 1 A, and held low while VCC is below the turn-on threshold."
      },
      {
        "number": "7",
        "name": "VCC",
        "type": "power_in",
        "description": "Power supply input for the analog controller and gate driver current; the datasheet recommends 12 V to 28 V operation, with an absolute maximum of 30 V from a low-impedance source, and a bypass capacitor of typically 0.1 µF to GROUND placed close to the pin."
      },
      {
        "number": "8",
        "name": "VREF",
        "type": "power_in",
        "description": "5 V reference output that must be bypassed to GROUND with at least 0.1 µF ceramic capacitor placed close to the pin, with an additional bypass needed for any external load, and the datasheet gives a reference output short-circuit current of -30 to -100 mA."
      }
    ],
    "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 multi-device family datasheet (UC1842–UC1845, UC2842–UC2845, UC3842–UC3845) and t; Pin type for COMP is taken from Table 5-1 (O). The text describes COMP as an open-collector error am; Pin 5 is printed as GROUND in the datasheet and is classified as power_in per the schema convention;"
        ],
        "pages_sent": 38,
        "cost_usd": 0.2173,
        "at": "2026-10-10T22:30:25"
      },
      "datasheet": {
        "url": "https://www.ti.com/cn/lit/gpn/uc2845",
        "pages": 61,
        "sha256": "0f875fd24cbb5fda",
        "source_tier": "lcsc"
      },
      "cad": "KiCad official (CC-BY-SA 4.0)",
      "pins": {
        "total": 8,
        "described": 8,
        "cites_pages": true,
        "refuses_to_fabricate": true
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        "zmin_mm": -3.3,
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        "checked": "2026-10-10",
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        "checked": "2026-10-10",
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  },
  "metadata": {
    "specs": {
      "Manufacturer": "Texas Instruments",
      "Package": "DIP-8",
      "Category": "Power Management (PMIC)",
      "Pins": "8"
    }
  },
  "variants": [],
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  "discovery_pitch": "UC3845N (Texas Instruments) component page: datasheet pinout, KiCad symbol, footprint and 3D.",
  "author": {
    "name": "Ray",
    "email": "[email protected]"
  },
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