LTC3891EUDC#TRPBF

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  "version": "0.1.0",
  "type": "component",
  "description": "Analog Devices DC-DC Controllers, QFN-20-EP(3x4). Pinout cross-checked by two models against the datasheet, KiCad symbol/footprint/3D.",
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  "component": {
    "mpn": "LTC3891EUDC#TRPBF",
    "manufacturer": "Analog Devices",
    "package": "QFN-20-EP(3x4)",
    "pin_count": 21,
    "category": "Power Management ICs",
    "subcategory": "DC-DC Controllers",
    "datasheet": "https://www.analog.com/media/en/technical-documentation/data-sheets/3891fa.pdf",
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    "distributor_links": {
      "lcsc": "C686998",
      "digikey": "505-LTC3891EUDC#TRPBFTR-ND",
      "mouser": "584-LTC3891EUDCTRPBF"
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    "distributor_check": {
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    "pins": [
      {
        "number": "1",
        "name": "PLLIN/MODE",
        "type": "input",
        "description": "External synchronization input to the phase detector and forced continuous mode input, with grounding selecting Burst Mode operation and tying to INTVCC forcing continuous inductor current."
      },
      {
        "number": "2",
        "name": "SGND",
        "type": "power_in",
        "description": "Small-signal ground that must be routed separately from high current grounds and electrically connected to pins 3 and 21 for proper operation."
      },
      {
        "number": "3",
        "name": "SGND",
        "type": "power_in",
        "description": "Small-signal ground that must be routed separately from high current grounds and electrically connected to pin 2 and pin 21 for proper operation."
      },
      {
        "number": "4",
        "name": "RUN",
        "type": "input",
        "description": "Digital run control input where forcing the pin below 1.16V shuts down the controller and below 0.7V shuts down the entire LTC3891 to about 14µA quiescent current."
      },
      {
        "number": "5",
        "name": "SENSE–",
        "type": "input",
        "description": "The (-) input to the differential current comparator, which supplies power to the current comparator when greater than INTVCC - 0.5V."
      },
      {
        "number": "6",
        "name": "SENSE+",
        "type": "input",
        "description": "The (+) input to the differential current comparator, normally connected to the DCR sensing network or current sensing resistor, which together with ITH and offsets sets the current trip threshold."
      },
      {
        "number": "7",
        "name": "VFB",
        "type": "input",
        "description": "Receives the remotely sensed feedback voltage from an external resistive divider across the output, regulated to the 0.8V reference."
      },
      {
        "number": "8",
        "name": "ITH",
        "type": "passive",
        "description": "Error amplifier output and switching regulator compensation point, where the current comparator trip point increases with this control voltage."
      },
      {
        "number": "9",
        "name": "PGOOD",
        "type": "output",
        "description": "Open-drain logic output that is pulled to ground when the VFB voltage is not within 10% of its set point."
      },
      {
        "number": "10",
        "name": "TG",
        "type": "output",
        "description": "High current gate drive for the top N-channel MOSFET, a floating driver with a voltage swing equal to INTVCC superimposed on the SW voltage."
      },
      {
        "number": "11",
        "name": "SW",
        "type": "passive",
        "description": "Switch node connection to the inductor."
      },
      {
        "number": "12",
        "name": "BOOST",
        "type": "power_out",
        "description": "Bootstrapped supply to the topside floating driver, with a voltage swing from INTVCC to (VIN + INTVCC) and a Schottky diode tied between BOOST and INTVCC."
      },
      {
        "number": "13",
        "name": "BG",
        "type": "output",
        "description": "High current gate drive for the bottom (synchronous) N-channel MOSFET, with a voltage swing from ground to INTVCC."
      },
      {
        "number": "14",
        "name": "INTVCC",
        "type": "power_out",
        "description": "Output of the internal linear low dropout regulator that powers the driver and control circuits, which must be decoupled to PGND with a minimum of 2.2µF ceramic or other low ESR capacitor."
      },
      {
        "number": "15",
        "name": "EXTVCC",
        "type": "power_in",
        "description": "External power input to an internal LDO connected to INTVCC that bypasses the VIN-powered LDO when EXTVCC is higher than 4.7V, and must not float or exceed 14V."
      },
      {
        "number": "16",
        "name": "PGND",
        "type": "power_in",
        "description": "Driver power ground connected to the source of the bottom synchronous N-channel MOSFET and the (-) terminal of CIN."
      },
      {
        "number": "17",
        "name": "VIN",
        "type": "power_in",
        "description": "Main supply pin that requires a bypass capacitor tied between this pin and the SGND pins, with an input supply operating range of 4V to 60V."
      },
      {
        "number": "18",
        "name": "ILIM",
        "type": "input",
        "description": "Current comparator sense voltage range input where tying the pin to SGND, FLOAT or INTVCC sets the maximum current sense threshold to one of three levels."
      },
      {
        "number": "19",
        "name": "TRACK/SS",
        "type": "input",
        "description": "External tracking and soft-start input to which the LTC3891 regulates VFB to the smaller of 0.8V or the TRACK/SS voltage, with an internal 10µA pull-up current source."
      },
      {
        "number": "20",
        "name": "FREQ",
        "type": "input",
        "description": "Frequency control pin for the internal VCO, where grounding forces 350kHz, INTVCC forces 535kHz, and a resistor to GND programs other frequencies between 50kHz and 900kHz."
      },
      {
        "number": "21",
        "name": "SGND",
        "type": "power_in",
        "description": "Exposed pad that is small-signal ground and must be soldered to PCB ground for rated thermal performance."
      }
    ],
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        "url": "https://www.analog.com/media/en/technical-documentation/data-sheets/3891fa.pdf",
        "pages": 32,
        "sha256": "21a46463d6a45e3c",
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      "pins": {
        "total": 21,
        "described": 21,
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