LTC2945CMS#PBF - Wide Range I2C Power Monitor

{
  "slug": "ltc2945cms-pbf",
  "version": "0.1.0",
  "type": "hardware",
  "kind": "component",
  "org": "adom",
  "title": "LTC2945CMS#PBF - Wide Range I2C Power Monitor",
  "brief": "Analog Devices (Linear Technology) LTC2945CMS#PBF: wide range I2C power monitor, 0 V to 80 V current and voltage sensing, 12-bit ADC, 24-bit power, min/max and alerts, split SDA for opto-isolation, 0 C to 70 C, MSOP-12. KiCad, Fusion and Altium libraries, 3D model and datasheet.",
  "description": "Analog Devices (Linear Technology) LTC2945CMS#PBF: rail-to-rail I2C power monitor; measures the voltage across a high- or low-side sense resistor (102.4 mV full scale) with a 0 V to 80 V common mode, the supply or SENSE+ voltage (102.4 V full scale) and an auxiliary input (2.048 V), multiplies current and voltage into a 24-bit power value, stores minimum and maximum and alerts on limits; runs from 2.7 V to 80 V (shunt regulator above 80 V); commercial temperature grade, 12-lead plastic MSOP (MS12, 3.00 x 4.039 mm body, 0.65 mm pitch).",
  "license": "CC-BY-4.0",
  "tags": [
    "component",
    "ic",
    "power-monitor",
    "current-sense",
    "i2c",
    "adc",
    "analog-devices",
    "linear-technology",
    "msop-12"
  ],
  "discovery_triggers": [
    "LTC2945CMS#PBF",
    "LTC2945CMS",
    "LTC2945",
    "LTC2945CMS-PBF",
    "I2C power monitor 80 V",
    "wide range power monitor MSOP-12"
  ],
  "hero": {
    "type": "image",
    "path": "docs/hero.png"
  },
  "visibility": {
    "public": true
  },
  "component": {
    "mpn": "LTC2945CMS#PBF",
    "manufacturer": "Analog Devices",
    "package": "MSOP-12 (ADI/LTC MS12, drawing 05-08-1668 Rev A, 3.00 x 4.039 mm body, 0.65 mm pitch)",
    "pin_count": 12,
    "category": "Power management",
    "subcategory": "Current, voltage and power monitor (I2C)",
    "lifecycle": "Active",
    "datasheet": "https://www.analog.com/media/en/technical-documentation/data-sheets/ltc2945.pdf",
    "product_page": "https://www.analog.com/en/products/ltc2945.html",
    "wiki_url": "https://wiki.adom.inc/adom/ltc2945cms-pbf",
    "body_size": {
      "x_mm": 3,
      "y_mm": 4.039,
      "z_mm": 1.1,
      "pitch_mm": 0.65
    },
    "parts": {
      "symbol": "ltc2945cms-pbf.kicad_sym",
      "footprint": "ltc2945cms-pbf.kicad_mod",
      "model_3d": "ltc2945cms-pbf-hero.glb",
      "model_3d_plain": "ltc2945cms-pbf-etched.glb",
      "model_3d_step": "ltc2945cms-pbf-etched.step",
      "model_3d_step_plain": "ltc2945cms-pbf.step",
      "step": "ltc2945cms-pbf-etched.step",
      "lbr": "ltc2945cms-pbf.lbr",
      "datasheet": "docs/ltc2945cms-pbf-datasheet.pdf"
    },
    "viewers": {
      "symbol": "viewers/symbol.html",
      "footprint": "viewers/footprint.html"
    },
    "viewer_3d": {
      "ground": false,
      "animate": false,
      "shadows": false,
      "tooltips": "authored"
    },
    "models": "models.json",
    "lod": "lod/manifest.json",
    "verification": "verification.json",
    "marking": {
      "lines": [
        "LTC2945",
        "CMS#PBF"
      ],
      "virtual": true,
      "note": "Virtual identification mark (the orderable MPN), not ADI's real top marking. ADI marks the MS12 LTC2945 parts 2945 (datasheet Rev. D p.4, Part marking column).",
      "surface": "top",
      "colour": "light on black epoxy",
      "gate": "PASS",
      "provenance": "provenance/3d-model.json"
    },
    "variants": "README.md#ordering-variants",
    "pins": [
      {
        "number": "1",
        "name": "VDD",
        "type": "power_in",
        "group": "Power",
        "description": "High-voltage supply input, 4 V to 80 V; feeds the internal series regulator that makes 5 V at INTVCC. Bypass with 0.1 uF to 1 uF when INTVCC carries an external load; the ADC can measure it (102.4 V full scale) (p.9)."
      },
      {
        "number": "2",
        "name": "INTVCC",
        "type": "power_in",
        "group": "Power",
        "description": "Internal low-voltage supply: a 2.7 V to 5.9 V input, or the 5 V output of the internal regulator (up to 10 mA) when VDD is 4 V to 80 V, or a 6.3 V shunt regulator. Bypass with 0.1 uF to 1 uF to GND (p.9)."
      },
      {
        "number": "3",
        "name": "ADR1",
        "type": "input",
        "group": "Address",
        "description": "I2C address input, three-state: tie to INTVCC, GND or leave open; with ADR0 selects one of nine addresses (p.9; Table 1, p.22)."
      },
      {
        "number": "4",
        "name": "ADR0",
        "type": "input",
        "group": "Address",
        "description": "I2C address input, three-state: tie to INTVCC, GND or leave open; with ADR1 selects one of nine addresses (p.9; Table 1, p.22)."
      },
      {
        "number": "5",
        "name": "ADIN",
        "type": "input",
        "group": "ADC input",
        "description": "Auxiliary ADC input, 0 V to 2.048 V full scale. Tie to GND if unused (p.9)."
      },
      {
        "number": "6",
        "name": "GND",
        "type": "power_in",
        "group": "Ground",
        "description": "Device ground (p.9)."
      },
      {
        "number": "7",
        "name": "SCL",
        "type": "input",
        "group": "I2C",
        "description": "I2C clock input; data at SDAI is shifted on rising SCL edges. Needs an external pull-up; internally clamped to 6.4 V (5.9 V min) (p.9)."
      },
      {
        "number": "8",
        "name": "SDAI",
        "type": "input",
        "group": "I2C",
        "description": "I2C data input for address, command and data bits. Needs an external pull-up; internally clamped to 6.4 V (5.9 V min). Tie to SDAO for a standard two-wire bus (p.9)."
      },
      {
        "number": "9",
        "name": "SDAO",
        "type": "open_collector",
        "group": "I2C",
        "description": "I2C data output, open drain, for read data and acknowledge. Needs an external pull-up. Split from SDAI for opto-isolated buses (p.9)."
      },
      {
        "number": "10",
        "name": "ALERT",
        "type": "open_collector",
        "group": "I2C",
        "description": "Fault alert output, open drain; pulled low after a conversion exceeds an enabled limit. SMBus alert compatible. Tie to GND if unused (p.9)."
      },
      {
        "number": "11",
        "name": "SENSE-",
        "type": "input",
        "group": "Current sense",
        "description": "Current sense input (load side of the sense resistor). The ADC measures SENSE+ minus SENSE- with a 102.4 mV full scale (p.9)."
      },
      {
        "number": "12",
        "name": "SENSE+",
        "type": "input",
        "group": "Current sense",
        "description": "Supply voltage and current sense input (high side of the sense resistor). Its voltage is also measured by the ADC with a 102.4 V full scale. Use a Kelvin connection to the sense resistor (Rev. D p.9; layout in Figure 19, p.21)."
      }
    ],
    "distributor_links": {
      "mouser": {
        "part": "584-LTC2945CMS#PBF",
        "url": "https://www.mouser.com/en/ProductDetail/Analog-Devices/LTC2945CMSPBF?qs=hVkxg5c3xu9Bwurjof%2F5lw%3D%3D",
        "stock": 78,
        "checked": "2026-10-21"
      },
      "digikey": {
        "part": "505-LTC2945CMS#PBF-ND",
        "url": "https://www.digikey.com/en/products/detail/analog-devices-inc/LTC2945CMS-PBF/3726462",
        "stock": 293,
        "checked": "2026-10-21"
      },
      "lcsc": false,
      "lcsc_note": "2026-10-21: JLCPCB/LCSC list no LTC2945CMS#PBF (the 0 C to 70 C grade). The industrial grade LTC2945IMS#PBF in the same MS12 package is C683688 (20 in stock at JLCPCB that day) and fits this footprint and symbol."
    },
    "provenance": {
      "datasheet": {
        "doc": "Analog Devices LTC2945 data sheet, Rev. D (June 2025)",
        "file": "docs/ltc2945cms-pbf-datasheet.pdf",
        "sha256": "a3fd01ed030bc213a0227e371ecc9aee4c363ddfc0d801f4ca5e90ea07e8beb5",
        "pages": 35
      },
      "package_drawing": {
        "doc": "LTC DWG 05-08-1668 Rev A, MS Package 12-Lead Plastic MSOP",
        "file": "docs/05081668_a_ms12.pdf",
        "sha256": "498f3c31775d84dd91f416b88a84698e6578283ee825559c0ac005312288f9c1"
      },
      "model_3d": "provenance/3d-model.json",
      "footprint": "provenance/footprint-check.json",
      "symbol": "provenance/symbol.json"
    }
  },
  "dependencies": {},
  "eda_assets": {
    "kicad": {
      "symbol": "ltc2945cms-pbf.kicad_sym",
      "footprint": "ltc2945cms-pbf.kicad_mod",
      "model": "ltc2945cms-pbf-etched.step",
      "provenance": "authored"
    },
    "fusion": {
      "lbr": "ltc2945cms-pbf.lbr",
      "provenance": "authored"
    },
    "altium": {
      "schlib": "altium/LTC2945CMS-PBF.SchLib",
      "pcblib": "altium/LTC2945CMS-PBF.PcbLib",
      "provenance": "authored"
    }
  },
  "source": {
    "tool": "analog-devices",
    "url": "https://www.analog.com/en/products/ltc2945.html"
  },
  "updated_at": "2026-10-21T19:04:01.599Z"
}