SN74221N

{
  "slug": "sn74221n",
  "version": "0.1.0",
  "type": "component",
  "description": "Texas Instruments Monostable Multivibrators, PDIP-16. Pinout cross-checked by two models against the datasheet, KiCad symbol/footprint/3D.",
  "tags": [
    "component",
    "logic ics",
    "sn74221n",
    "factory-2.0.0",
    "extractor-text"
  ],
  "dependencies": {},
  "hero": {
    "type": "image",
    "path": "docs/hero.png"
  },
  "files": [
    "page.json",
    "README.md",
    "sn74221n.kicad_sym",
    "sn74221n.kicad_mod",
    "sn74221n.glb",
    "sn74221n.step",
    "sn74221n.lbr",
    "docs/hero.png",
    "docs/sn74221n-datasheet.pdf",
    "viewers/symbol.html",
    "viewers/footprint.html",
    "sn74221n-hero.glb",
    "sn74221n-hero.overlay.json",
    "sn74221n-etched.glb"
  ],
  "component": {
    "mpn": "SN74221N",
    "manufacturer": "Texas Instruments",
    "package": "PDIP-16",
    "pin_count": 16,
    "category": "Logic ICs",
    "subcategory": "Monostable Multivibrators",
    "datasheet": "https://www.ti.com/lit/ds/symlink/sn74221n.pdf",
    "parts": {
      "symbol": "sn74221n.kicad_sym",
      "footprint": "sn74221n.kicad_mod",
      "model_3d": "sn74221n-hero.glb",
      "model_3d_plain": "sn74221n-etched.glb",
      "model_3d_step": "sn74221n-etched.step",
      "model_3d_step_plain": "sn74221n.step",
      "lbr": "sn74221n.lbr"
    },
    "distributor_links": {
      "lcsc": "C1522772",
      "digikey": "2156-SN74221N-ND",
      "mouser": "595-SN74221N"
    },
    "distributor_check": {
      "checked_at": "2026-10-28T16:40:19Z",
      "source": "Component Ocean /api/assign-pns",
      "digikey": {
        "pn": "2156-SN74221N-ND",
        "status": "found"
      },
      "mouser": {
        "pn": "595-SN74221N",
        "status": "found"
      }
    },
    "pins": [
      {
        "number": "1",
        "name": "1A",
        "type": "input",
        "description": "Negative-transition-triggered input of multivibrator 1 that can also be used as an inhibit input."
      },
      {
        "number": "2",
        "name": "1B",
        "type": "input",
        "description": "Positive-transition-triggered Schmitt-trigger input of multivibrator 1 with TTL hysteresis, typically 1.2 V noise immunity."
      },
      {
        "number": "3",
        "name": "1CLR",
        "type": "input",
        "description": "Overriding clear input of multivibrator 1 that terminates the output pulse."
      },
      {
        "number": "4",
        "name": "~{1Q}",
        "type": "output",
        "description": "Complementary output of multivibrator 1, which goes low during the timed output pulse."
      },
      {
        "number": "5",
        "name": "2Q",
        "type": "output",
        "description": "Complementary output of multivibrator 2, which goes low during the timed output pulse."
      },
      {
        "number": "6",
        "name": "2Cext",
        "type": "passive",
        "description": "External timing capacitor connection for multivibrator 2, with Cext from 0 to 1000 µF per recommended operating conditions."
      },
      {
        "number": "7",
        "name": "2Rext/Cext",
        "type": "passive",
        "description": "External timing resistor and capacitor connection for multivibrator 2, with Rext from 1.4 kΩ to 40 kΩ for SN74221."
      },
      {
        "number": "8",
        "name": "GND",
        "type": "power_in",
        "description": "Ground reference pin; all unused inputs must be held at VCC or GND for proper operation."
      },
      {
        "number": "9",
        "name": "2A",
        "type": "input",
        "description": "Negative-transition-triggered input of multivibrator 2 that can also be used as an inhibit input."
      },
      {
        "number": "10",
        "name": "2B",
        "type": "input",
        "description": "Positive-transition-triggered Schmitt-trigger input of multivibrator 2 with TTL hysteresis."
      },
      {
        "number": "11",
        "name": "2CLR",
        "type": "input",
        "description": "Overriding clear input of multivibrator 2 that terminates the output pulse."
      },
      {
        "number": "12",
        "name": "2Q",
        "type": "output",
        "description": "True output of multivibrator 2, which goes high during the timed output pulse."
      },
      {
        "number": "13",
        "name": "1Q",
        "type": "output",
        "description": "True output of multivibrator 1, which goes high during the timed output pulse."
      },
      {
        "number": "14",
        "name": "1Cext",
        "type": "passive",
        "description": "External timing capacitor connection for multivibrator 1, with Cext from 0 to 1000 µF per recommended operating conditions."
      },
      {
        "number": "15",
        "name": "1Rext/Cext",
        "type": "passive",
        "description": "External timing resistor and capacitor connection for multivibrator 1, with Rext from 1.4 kΩ to 40 kΩ for SN74221."
      },
      {
        "number": "16",
        "name": "VCC",
        "type": "power_in",
        "description": "Supply voltage pin, 4.75 V minimum to 5.25 V maximum recommended for SN74221."
      }
    ],
    "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 assignments were reconstructed from garbled top-view text extraction on page 1 because the overb"
        ],
        "pages_sent": 32,
        "cost_usd": 0.0348,
        "at": "2026-10-28T16:40:07"
      },
      "datasheet": {
        "url": "https://www.ti.com/lit/ds/symlink/sn74221n.pdf",
        "pages": 32,
        "sha256": "362570aaf7b623a7",
        "source_tier": "mfr"
      },
      "cad": "KiCad official (CC-BY-SA 4.0)",
      "pins": {
        "total": 16,
        "described": 16,
        "cites_pages": true,
        "refuses_to_fabricate": true
      }
    },
    "viewers": {
      "symbol": "viewers/symbol.html",
      "footprint": "viewers/footprint.html"
    },
    "models_3d": [
      {
        "file": "sn74221n.step",
        "role": "plain",
        "up": "Z",
        "units": "mm",
        "origin": "footprint origin = pad-pattern centre",
        "seat": "body on z = 0, through-hole leads below",
        "extents_mm": [
          7.874,
          19.177,
          6.98
        ],
        "zmin_mm": -3.3,
        "centre_offset_mm": 0.0,
        "footprint_binding": "identity",
        "sha256": "17a30b1f0ab3fd5384a1231e3c63c394888d5b952c542a8c189e023ed3467464",
        "checked": "2026-10-28",
        "checked_by": "factory/step_pose.py (Z-up, origin, seat, binding)"
      },
      {
        "file": "sn74221n-etched.step",
        "role": "eda",
        "up": "Z",
        "units": "mm",
        "origin": "footprint origin = pad-pattern centre",
        "seat": "body on z = 0, through-hole leads below",
        "extents_mm": [
          7.874,
          19.177,
          6.98
        ],
        "zmin_mm": -3.3,
        "centre_offset_mm": 0.0,
        "footprint_binding": "identity",
        "sha256": "580887e1adc79e0678b66f278efc02059d853fa3da27542e967120dee62b440b",
        "checked": "2026-10-28",
        "checked_by": "factory/step_pose.py (Z-up, origin, seat, binding)"
      }
    ]
  }
}