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Ray pin 1: carry the footprint's marker into the .lbr, the viewer and page.json (silk-marker, drawn, top-left) 851e2a3
{
 "schema": "adom.pads/1",
 "slug": "tx4138",
 "footprint": "SOIC-8-1EP_3.9x4.9mm_P1.27mm_EP2.29x3mm",
 "generated_from": {
  "footprint": "SOIC-8-1EP_3.9x4.9mm_P1.27mm_EP2.29x3mm@sha256:a7971720bdda0353",
  "pins": "page.json:component.pins",
  "overrides": null
 },
 "pin1": {
  "pad": "1",
  "at": [
   -2.475,
   -1.905
  ],
  "corner": "top-left",
  "source": "silk-marker",
  "derived_from": "SOIC-8-1EP_3.9x4.9mm_P1.27mm_EP2.29x3mm@sha256:a7971720bdda0353"
 },
 "pad_count": 9,
 "symbol_pins": [
  "1",
  "2",
  "3",
  "4",
  "5",
  "6",
  "7",
  "8",
  "9"
 ],
 "paste_apertures": 4,
 "issues": [],
 "pads": [
  {
   "pad": "1",
   "kind": "smd",
   "shape": "roundrect",
   "at": [
    -2.475,
    -1.905
   ],
   "rot": 0.0,
   "size": [
    1.95,
    0.6
   ],
   "layers": [
    "F.Cu",
    "F.Mask",
    "F.Paste"
   ],
   "thermal": false,
   "pin": "1",
   "name": "SW",
   "type": "output",
   "description": "Switch node output. Source of the internal high-side power MOSFET; connect this pin to the switching end of the inductor and to the cathode of the external freewheeling Schottky diode. Absolute maximum: -0.3V to VIN + 0.3V.",
   "is_pin1": true,
   "source": {
    "geometry": "SOIC-8-1EP_3.9x4.9mm_P1.27mm_EP2.29x3mm.kicad_mod",
    "meaning": "page.json:component.pins",
    "correspondence": "kicad: symbol pin number == pad name"
   }
  },
  {
   "pad": "2",
   "kind": "smd",
   "shape": "roundrect",
   "at": [
    -2.475,
    -0.635
   ],
   "rot": 0.0,
   "size": [
    1.95,
    0.6
   ],
   "layers": [
    "F.Cu",
    "F.Mask",
    "F.Paste"
   ],
   "thermal": false,
   "pin": "2",
   "name": "ILIM",
   "type": "power_in",
   "description": "Programmable maximum peak current pin. Power current flows into the chip through an external accurate sense resistor connected between ILIM and VIN; the sense resistor value (~15-30mΩ) sets the peak current limit (30mΩ for 2A, 20mΩ for 3A, 15mΩ for 4A). Internally tied to the power MOSFET, so heat dissipation on this pin matters. Absolute maximum: 62V.",
   "is_pin1": false,
   "source": {
    "geometry": "SOIC-8-1EP_3.9x4.9mm_P1.27mm_EP2.29x3mm.kicad_mod",
    "meaning": "page.json:component.pins",
    "correspondence": "kicad: symbol pin number == pad name"
   }
  },
  {
   "pad": "3",
   "kind": "smd",
   "shape": "roundrect",
   "at": [
    -2.475,
    0.635
   ],
   "rot": 0.0,
   "size": [
    1.95,
    0.6
   ],
   "layers": [
    "F.Cu",
    "F.Mask",
    "F.Paste"
   ],
   "thermal": false,
   "pin": "3",
   "name": "VIN",
   "type": "power_in",
   "description": "Supply voltage input, 4.5V to 60V unregulated. Also the drain of the internal high-side power MOSFET and power supply for the whole chip. A local input capacitor (CIN) placed as close to the IC as possible is required to prevent large voltage spikes. Absolute maximum: 62V.",
   "is_pin1": false,
   "source": {
    "geometry": "SOIC-8-1EP_3.9x4.9mm_P1.27mm_EP2.29x3mm.kicad_mod",
    "meaning": "page.json:component.pins",
    "correspondence": "kicad: symbol pin number == pad name"
   }
  },
  {
   "pad": "4",
   "kind": "smd",
   "shape": "roundrect",
   "at": [
    -2.475,
    1.905
   ],
   "rot": 0.0,
   "size": [
    1.95,
    0.6
   ],
   "layers": [
    "F.Cu",
    "F.Mask",
    "F.Paste"
   ],
   "thermal": false,
   "pin": "4",
   "name": "GND",
   "type": "power_in",
   "description": "Ground return and voltage reference for the regulated output. Should be routed carefully outside the D1-to-CIN high-current ground path to prevent switching current spikes from injecting noise into the part.",
   "is_pin1": false,
   "source": {
    "geometry": "SOIC-8-1EP_3.9x4.9mm_P1.27mm_EP2.29x3mm.kicad_mod",
    "meaning": "page.json:component.pins",
    "correspondence": "kicad: symbol pin number == pad name"
   }
  },
  {
   "pad": "5",
   "kind": "smd",
   "shape": "roundrect",
   "at": [
    2.475,
    1.905
   ],
   "rot": 0.0,
   "size": [
    1.95,
    0.6
   ],
   "layers": [
    "F.Cu",
    "F.Mask",
    "F.Paste"
   ],
   "thermal": false,
   "pin": "5",
   "name": "FB",
   "type": "input",
   "description": "Feedback input to the error amplifier. An external resistor divider from VOUT to GND, tapped to FB, sets the output voltage; reference is 0.805V (typ, 0.785-0.825V). When FB falls below 250mV a frequency-fold-back comparator reduces oscillator frequency to prevent short-circuit current-limit runaway. Bias current ~10nA. Absolute maximum: -0.3V to +6.5V.",
   "is_pin1": false,
   "source": {
    "geometry": "SOIC-8-1EP_3.9x4.9mm_P1.27mm_EP2.29x3mm.kicad_mod",
    "meaning": "page.json:component.pins",
    "correspondence": "kicad: symbol pin number == pad name"
   }
  },
  {
   "pad": "6",
   "kind": "smd",
   "shape": "roundrect",
   "at": [
    2.475,
    0.635
   ],
   "rot": 0.0,
   "size": [
    1.95,
    0.6
   ],
   "layers": [
    "F.Cu",
    "F.Mask",
    "F.Paste"
   ],
   "thermal": false,
   "pin": "6",
   "name": "EN",
   "type": "input",
   "description": "Enable input. Drive low to disable (turn off) the chip; leave floating (or drive high) to enable. Absolute maximum: -0.3V to +6.5V.",
   "is_pin1": false,
   "source": {
    "geometry": "SOIC-8-1EP_3.9x4.9mm_P1.27mm_EP2.29x3mm.kicad_mod",
    "meaning": "page.json:component.pins",
    "correspondence": "kicad: symbol pin number == pad name"
   }
  },
  {
   "pad": "7",
   "kind": "smd",
   "shape": "roundrect",
   "at": [
    2.475,
    -0.635
   ],
   "rot": 0.0,
   "size": [
    1.95,
    0.6
   ],
   "layers": [
    "F.Cu",
    "F.Mask",
    "F.Paste"
   ],
   "thermal": false,
   "pin": "7",
   "name": "POK",
   "type": "output",
   "description": "Power-good open-drain output. Pulled low while FB is less than 90% of the 0.8V reference; goes high-Z when output is in regulation. Requires an external pull-up (e.g. 10kΩ) to a system rail up to 45V; can also drive the enable pin of a downstream converter. Tie to GND or leave floating if unused. Absolute maximum: 0V to 45V.",
   "is_pin1": false,
   "source": {
    "geometry": "SOIC-8-1EP_3.9x4.9mm_P1.27mm_EP2.29x3mm.kicad_mod",
    "meaning": "page.json:component.pins",
    "correspondence": "kicad: symbol pin number == pad name"
   }
  },
  {
   "pad": "8",
   "kind": "smd",
   "shape": "roundrect",
   "at": [
    2.475,
    -1.905
   ],
   "rot": 0.0,
   "size": [
    1.95,
    0.6
   ],
   "layers": [
    "F.Cu",
    "F.Mask",
    "F.Paste"
   ],
   "thermal": false,
   "pin": "8",
   "name": "BS",
   "type": "passive",
   "description": "Bootstrap capacitor pin. Provides the positive supply rail for the high-side MOSFET gate driver (VBST - VSW = 6V typ). Connect a 100nF ceramic capacitor and a series ~5-10Ω resistor between BS and SW. Absolute maximum: VSW + 6.0V.",
   "is_pin1": false,
   "source": {
    "geometry": "SOIC-8-1EP_3.9x4.9mm_P1.27mm_EP2.29x3mm.kicad_mod",
    "meaning": "page.json:component.pins",
    "correspondence": "kicad: symbol pin number == pad name"
   }
  },
  {
   "pad": "9",
   "kind": "smd",
   "shape": "rect",
   "at": [
    0.0,
    0.0
   ],
   "rot": 0.0,
   "size": [
    2.29,
    3.0
   ],
   "layers": [],
   "thermal": true,
   "pin": "9",
   "name": "ILIM (EP)",
   "type": "power_in",
   "description": "Exposed thermal pad, internally connected to the ILIM node (same net as pin 2). Provides the primary heat-dissipation path for the internal power MOSFET and must be soldered to a copper pour that also carries the ILIM/sense-resistor current back to VIN.",
   "is_pin1": false,
   "source": {
    "geometry": "SOIC-8-1EP_3.9x4.9mm_P1.27mm_EP2.29x3mm.kicad_mod",
    "meaning": "page.json:component.pins",
    "correspondence": "kicad: symbol pin number == pad name"
   }
  }
 ]
}