UCC3818DTR

{
  "slug": "ucc3818dtr",
  "version": "0.1.0",
  "type": "component",
  "description": "Texas Instruments AC-DC Controllers And Regulators, SOIC-16. Pinout cross-checked by two models against the datasheet, KiCad symbol/footprint/3D.",
  "tags": [
    "component",
    "power management (pmic)",
    "ucc3818dtr",
    "factory-2.0.0",
    "extractor-text"
  ],
  "dependencies": {},
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    "type": "image",
    "path": "docs/hero.png"
  },
  "files": [
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    "README.md",
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    "ucc3818dtr.kicad_mod",
    "ucc3818dtr.glb",
    "ucc3818dtr.step",
    "ucc3818dtr.lbr",
    "docs/hero.png",
    "docs/ucc3818dtr-datasheet.pdf",
    "viewers/symbol.html",
    "viewers/footprint.html",
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  "component": {
    "mpn": "UCC3818DTR",
    "manufacturer": "Texas Instruments",
    "package": "SOIC-16",
    "pin_count": 16,
    "category": "Power Management (PMIC)",
    "subcategory": "AC-DC Controllers And Regulators",
    "datasheet": "https://www.ti.com/cn/lit/gpn/ucc3818",
    "parts": {
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      "model_3d_plain": "ucc3818dtr.glb",
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      "lbr": "ucc3818dtr.lbr"
    },
    "distributor_links": {
      "lcsc": "C471051",
      "digikey": "296-41818-2-ND",
      "mouser": "595-UCC3818DTR"
    },
    "distributor_check": {
      "checked_at": "2026-10-11T20:49:33Z",
      "source": "Component Ocean /api/assign-pns",
      "digikey": {
        "pn": "296-41818-2-ND",
        "status": "found"
      },
      "mouser": {
        "pn": "595-UCC3818DTR",
        "status": "found"
      }
    },
    "pins": [
      {
        "number": "1",
        "name": "GND",
        "type": "power_in",
        "description": "Ground reference for all voltages; VCC and VREF should be bypassed directly to GND with a 0.1-µF or larger ceramic capacitor."
      },
      {
        "number": "2",
        "name": "PKLMT",
        "type": "input",
        "description": "PFC peak current limit with a threshold of 0 V, reached when the PKLMT voltage falls below 0 V; level-shift it from the negative side of the sense resistor to VREF through a resistor divider."
      },
      {
        "number": "3",
        "name": "CAOUT",
        "type": "output",
        "description": "Current amplifier output from a wide-bandwidth op amp that commands the PFC PWM duty cycle, with compensation components placed between CAOUT and MOUT."
      },
      {
        "number": "4",
        "name": "CAI",
        "type": "input",
        "description": "Current amplifier noninverting input, which should connect through a resistor to the GND side of the current sense resistor and remains functional down to and below GND."
      },
      {
        "number": "5",
        "name": "MOUT",
        "type": "bidirectional",
        "description": "Multiplier output and current amplifier inverting input, a high-impedance node whose multiplier output current is limited to 2 × IIAC."
      },
      {
        "number": "6",
        "name": "IAC",
        "type": "input",
        "description": "Current input proportional to instantaneous line voltage to the analog multiplier, with a recommended maximum IIAC of 500 µA."
      },
      {
        "number": "7",
        "name": "VAOUT",
        "type": "output",
        "description": "Voltage amplifier output that regulates output voltage, internally limited to approximately 5.5 V to prevent overshoot."
      },
      {
        "number": "8",
        "name": "VFF",
        "type": "input",
        "description": "Feed-forward voltage generated by mirroring 1/2 of IIAC into an external single-pole filter, which should be 1.4 V at low line."
      },
      {
        "number": "9",
        "name": "VREF",
        "type": "power_in",
        "description": "Accurate 7.5-V voltage reference output capable of delivering 20 mA to peripheral circuitry, internally short-circuit current-limited, and disabled at 0 V when VCC is below the UVLO threshold; bypass with 0.1 µF or larger."
      },
      {
        "number": "10",
        "name": "OVP/EN",
        "type": "input",
        "description": "Window comparator input that disables the output driver when the boost output is a programmed level above nominal and disables the driver and resets SS when pulled below 1.9 V (typ), with a maximum input voltage of 10 V."
      },
      {
        "number": "11",
        "name": "VSENSE",
        "type": "input",
        "description": "Voltage amplifier inverting input, normally connected to a compensation network and to the boost output through a divider; maximum input voltage 10 V."
      },
      {
        "number": "12",
        "name": "RT",
        "type": "input",
        "description": "Oscillator charging current programming pin; a resistor between 10 kΩ and 100 kΩ to GND is recommended, with a nominal voltage of 3 V on this pin."
      },
      {
        "number": "13",
        "name": "SS",
        "type": "input",
        "description": "Soft-start pin that is discharged when VCC is low, charges an external capacitor through a current source when enabled, and is limited to 8 V maximum input voltage."
      },
      {
        "number": "14",
        "name": "CT",
        "type": "input",
        "description": "Oscillator timing capacitor from CT to GND that sets the PWM frequency per f ≈ 0.6/(RT × CT), with the GND lead kept as short as possible."
      },
      {
        "number": "15",
        "name": "VCC",
        "type": "power_in",
        "description": "Positive supply that should be held between 10 V and 17 V (at least 20 mA) for normal operation, with an 18 V absolute maximum rating, and bypassed directly to GND; outputs are inhibited unless VCC exceeds the upper UVLO threshold and stays above the lower threshold."
      },
      {
        "number": "16",
        "name": "DRVOUT",
        "type": "output",
        "description": "Totem-pole MOSFET gate drive output for the boost switch, which requires a series gate resistor to limit overshoot when driving a capacitive load."
      }
    ],
    "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 labels MOUT as I/O, so it is typed bidirectional here to match the KiCad class; verify; The datasheet labels VCC as an input (I), but it is the device supply, so it is typed power_in. Conf; The datasheet is internally inconsistent on the reference voltage: the pin description and Figure te"
        ],
        "pages_sent": 13,
        "cost_usd": 0.0827,
        "at": "2026-10-11T20:49:16"
      },
      "datasheet": {
        "url": "https://www.ti.com/cn/lit/gpn/ucc3818",
        "pages": 46,
        "sha256": "ca94b4ec262a1f44",
        "source_tier": "lcsc"
      },
      "cad": "KiCad official (CC-BY-SA 4.0)",
      "pins": {
        "total": 16,
        "described": 16,
        "cites_pages": true,
        "refuses_to_fabricate": true
      }
    },
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        "checked": "2026-10-11",
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}