LTC3891EUDC#TRPBF

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  "title": "LTC3891EUDC#TRPBF",
  "brief": "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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    "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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      "digikey": "505-LTC3891EUDC#TRPBFTR-ND",
      "mouser": "584-LTC3891EUDCTRPBF"
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      {
        "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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          "name": "Input Supply Operating Voltage Range",
          "symbol": "VIN",
          "kind": "recommended_operating",
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          "min": 0.792,
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          "conditions": "ITH Voltage = 1.2V; -40C to 85C; LTC3891E, LTC3891I",
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          "kind": "electrical",
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          "conditions": "VIN = 4.5V to 60V; Note 4",
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        {
          "name": "Output Voltage Load Regulation",
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          "kind": "electrical",
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          "min": null,
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          "name": "Input DC Supply Current, Pulse Skip or Forced Continuous Mode",
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          "conditions": "VFB = 0.83V (No Load)",
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        {
          "name": "Input DC Supply Current, Sleep Mode",
          "symbol": "IQ",
          "kind": "electrical",
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          "max": 75,
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          "max": 25,
          "conditions": "RUN = 0V",
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        {
          "name": "Feedback Overvoltage Protection",
          "symbol": "VOVL",
          "kind": "electrical",
          "unit": "%",
          "min": 7,
          "typ": 10,
          "max": 13,
          "conditions": "Measured at VFB Relative to Regulated VFB",
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          "kind": "electrical",
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          "name": "Maximum Duty Factor",
          "symbol": "DFMAX",
          "kind": "electrical",
          "unit": "%",
          "min": 98,
          "typ": 99,
          "max": null,
          "conditions": "In Dropout",
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          "name": "Soft-Start Charge Current",
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          "kind": "electrical",
          "unit": "µA",
          "min": 7,
          "typ": 10,
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          "symbol": "VRUN",
          "kind": "electrical",
          "unit": "V",
          "min": 1.15,
          "typ": 1.21,
          "max": 1.27,
          "conditions": "VRUN Rising",
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          "name": "Maximum Current Sense Threshold",
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          "kind": "electrical",
          "unit": "mV",
          "min": 22,
          "typ": 30,
          "max": 36,
          "conditions": "VFB = 0.7V, VSENSE– = 3.3V, ILIM = 0",
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          "name": "Maximum Current Sense Threshold",
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          "conditions": "VFB = 0.7V, VSENSE– = 3.3V, ILIM = INTVCC",
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          "conditions": "VFB = 0.7V, VSENSE– = 3.3V, ILIM = FLOAT",
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          "name": "INTVCC Internal VCC Voltage (VIN)",
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          "kind": "electrical",
          "unit": "V",
          "min": 4.85,
          "typ": 5.1,
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          "kind": "electrical",
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          "name": "EXTVCC Switchover Voltage",
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          "name": "Low Fixed Frequency",
          "symbol": "fLOW",
          "kind": "electrical",
          "unit": "kHz",
          "min": 320,
          "typ": 350,
          "max": 380,
          "conditions": "VFREQ = 0V; PLLIN/MODE = DC Voltage",
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          "name": "High Fixed Frequency",
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          "min": 485,
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          "max": 585,
          "conditions": "VFREQ = INTVCC; PLLIN/MODE = DC Voltage",
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        {
          "name": "Programmable Frequency",
          "symbol": "f65kΩ",
          "kind": "electrical",
          "unit": "kHz",
          "min": 375,
          "typ": 440,
          "max": 505,
          "conditions": "RFREQ = 65k; PLLIN/MODE = DC Voltage",
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          "name": "Synchronizable Frequency",
          "symbol": "fSYNC",
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          "min": 75,
          "typ": null,
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          "conditions": "PLLIN/MODE = External Clock",
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          "name": "PGOOD Voltage Low",
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          "kind": "electrical",
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          "conditions": "IPGOOD = 2mA",
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          "name": "PGOOD Leakage Current",
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          "conditions": "VPGOOD = 5V",
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        {
          "name": "PGOOD Trip Level, VFB Ramping Negative",
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          "name": "PGOOD Trip Level, VFB Ramping Positive",
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