LT3991EMSE-5#PBF

{
  "slug": "lt3991emse-5-pbf",
  "version": "0.1.0",
  "type": "component",
  "description": "Analog Devices DC-DC Converters, MSOP-10-EP. Pinout cross-checked by two models against the datasheet, KiCad symbol/footprint/3D.",
  "tags": [
    "component",
    "power management ics",
    "lt3991emse-5#pbf",
    "factory-2.0.0",
    "extractor-text"
  ],
  "dependencies": {},
  "hero": {
    "type": "image",
    "path": "docs/hero.png"
  },
  "files": [
    "page.json",
    "README.md",
    "lt3991emse-5-pbf.kicad_sym",
    "lt3991emse-5-pbf.kicad_mod",
    "lt3991emse-5-pbf.glb",
    "lt3991emse-5-pbf.step",
    "lt3991emse-5-pbf.lbr",
    "docs/hero.png",
    "docs/lt3991emse-5-pbf-datasheet.pdf",
    "viewers/symbol.html",
    "viewers/footprint.html",
    "lt3991emse-5-pbf-hero.glb",
    "lt3991emse-5-pbf-hero.overlay.json",
    "lt3991emse-5-pbf-etched.glb"
  ],
  "component": {
    "mpn": "LT3991EMSE-5#PBF",
    "manufacturer": "Analog Devices",
    "package": "MSOP-10-EP",
    "pin_count": 11,
    "category": "Power Management ICs",
    "subcategory": "DC-DC Converters",
    "datasheet": "https://www.analog.com/media/en/technical-documentation/data-sheets/3991fa.pdf",
    "parts": {
      "symbol": "lt3991emse-5-pbf.kicad_sym",
      "footprint": "lt3991emse-5-pbf.kicad_mod",
      "model_3d": "lt3991emse-5-pbf-hero.glb",
      "model_3d_plain": "lt3991emse-5-pbf-etched.glb",
      "model_3d_step": "lt3991emse-5-pbf-etched.step",
      "model_3d_step_plain": "lt3991emse-5-pbf.step",
      "lbr": "lt3991emse-5-pbf.lbr"
    },
    "distributor_links": {
      "lcsc": "C671881",
      "digikey": "LT3991EMSE-5#PBF-ND",
      "mouser": "584-LT3991EMSE-5#PBF"
    },
    "distributor_check": {
      "checked_at": "2026-10-28T15:45:24Z",
      "source": "Component Ocean /api/assign-pns",
      "digikey": {
        "pn": "LT3991EMSE-5#PBF-ND",
        "status": "found"
      },
      "mouser": {
        "pn": "584-LT3991EMSE-5#PBF",
        "status": "found"
      }
    },
    "pins": [
      {
        "number": "1",
        "name": "BD",
        "type": "passive",
        "description": "Connects to the anode of the boost Schottky diode and is normally connected to the output."
      },
      {
        "number": "2",
        "name": "BOOST",
        "type": "power_in",
        "description": "Provides a drive voltage higher than the input voltage to the internal NPN power switch, supplied through an external boost capacitor."
      },
      {
        "number": "3",
        "name": "SW",
        "type": "output",
        "description": "Output of the internal power switch; connects to the inductor, catch diode and boost capacitor."
      },
      {
        "number": "4",
        "name": "VIN",
        "type": "power_in",
        "description": "Supplies current to the internal circuitry and power switch over the 4.3V to 55V input range and must be locally bypassed."
      },
      {
        "number": "5",
        "name": "EN",
        "type": "input",
        "description": "Shutdown when low and active when high, with 1.005V rising and 0.975V falling thresholds; the threshold is only accurate when VIN is above 4.3V."
      },
      {
        "number": "6",
        "name": "VOUT",
        "type": "input",
        "description": "On the LT3991-5 this pin regulates the output to 5V and connects to the internal 10MΩ feedback divider that programs the fixed output voltage."
      },
      {
        "number": "7",
        "name": "SS",
        "type": "passive",
        "description": "A capacitor and series resistor to ground slowly ramp the peak current limit on start-up; the typical soft-start resistor is 100k, and floating the pin disables soft-start."
      },
      {
        "number": "8",
        "name": "RT",
        "type": "passive",
        "description": "A resistor tied between RT and ground sets the switching frequency."
      },
      {
        "number": "9",
        "name": "PG",
        "type": "output",
        "description": "Open-drain power good output that remains low until the FB pin is within 9% of the final regulation voltage and is valid when the part is enabled and VIN is above 4.3V."
      },
      {
        "number": "10",
        "name": "SYNC",
        "type": "input",
        "description": "External clock synchronization input; grounding it gives low-ripple Burst Mode operation at low output loads, while a clock source synchronizes the switching frequency with pulse-skipping at low loads."
      },
      {
        "number": "11",
        "name": "GND",
        "type": "power_in",
        "description": "Ground; the exposed pad must be soldered to the PCB."
      }
    ],
    "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: Pin 6 is labeled VOUT for the LT3991-5 variant (FB on the adjustable LT3991). The package is MSE 10-"
        ],
        "pages_sent": 7,
        "cost_usd": 0.0166,
        "at": "2026-10-28T15:45:15"
      },
      "datasheet": {
        "url": "https://www.analog.com/media/en/technical-documentation/data-sheets/3991fa.pdf",
        "pages": 24,
        "sha256": "05394db5ad4d382a",
        "source_tier": "mfr"
      },
      "cad": "KiCad official (CC-BY-SA 4.0)",
      "pins": {
        "total": 11,
        "described": 11,
        "cites_pages": true,
        "refuses_to_fabricate": true
      }
    },
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      "footprint": "viewers/footprint.html"
    },
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        "file": "lt3991emse-5-pbf.step",
        "role": "plain",
        "up": "Z",
        "units": "mm",
        "origin": "footprint origin = pad-pattern centre",
        "seat": "z = 0",
        "extents_mm": [
          4.9,
          3.0,
          0.95
        ],
        "zmin_mm": -0.0,
        "centre_offset_mm": 0.0,
        "footprint_binding": "identity",
        "sha256": "18605eed706df7bb9674107abe7aa36e0ba163a09c21a2cee6c75cfa291b7937",
        "checked": "2026-10-28",
        "checked_by": "factory/step_pose.py (Z-up, origin, seat, binding)"
      },
      {
        "file": "lt3991emse-5-pbf-etched.step",
        "role": "eda",
        "up": "Z",
        "units": "mm",
        "origin": "footprint origin = pad-pattern centre",
        "seat": "z = 0",
        "extents_mm": [
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        "zmin_mm": -0.0,
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        "sha256": "b3fa0c691c1ec6b1487199e06a8b3d51f0d88e83e667efcb5655a5f2f370cfe7",
        "checked": "2026-10-28",
        "checked_by": "factory/step_pose.py (Z-up, origin, seat, binding)"
      }
    ]
  }
}