SN74HC540 Octal Inverting Buffer

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  "type": "component",
  "slug": "sn74hc540",
  "title": "SN74HC540 Octal Inverting Buffer",
  "brief": "Octal inverting buffer and line driver with 3-state outputs and a flow-through pinout.",
  "version": "0.1.0",
  "license": "CC-BY-SA-4.0",
  "tags": [
    "logic",
    "buffer",
    "inverting",
    "line-driver",
    "3-state",
    "74hc",
    "ti",
    "soic-20"
  ],
  "component": {
    "mpn": "SN74HC540",
    "manufacturer": "Texas Instruments",
    "package": "SOIC-20",
    "pin_count": 20,
    "category": "Logic",
    "subcategory": "Buffer / Line Driver",
    "datasheet": "https://www.ti.com/lit/ds/symlink/sn74hc540.pdf",
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    "pins": [
      {
        "number": "1",
        "name": "OE1",
        "type": "input",
        "description": "Active-low output-enable 1. NORed with OE2; when either OE input is high, all Y outputs are in high-impedance state."
      },
      {
        "number": "2",
        "name": "A1",
        "type": "input",
        "description": "Data input for channel 1. CMOS logic input; drives inverted output Y1 when device is enabled."
      },
      {
        "number": "3",
        "name": "A2",
        "type": "input",
        "description": "Data input for channel 2. Drives inverted output Y2 when device is enabled."
      },
      {
        "number": "4",
        "name": "A3",
        "type": "input",
        "description": "Data input for channel 3. Drives inverted output Y3 when device is enabled."
      },
      {
        "number": "5",
        "name": "A4",
        "type": "input",
        "description": "Data input for channel 4. Drives inverted output Y4 when device is enabled."
      },
      {
        "number": "6",
        "name": "A5",
        "type": "input",
        "description": "Data input for channel 5. Drives inverted output Y5 when device is enabled."
      },
      {
        "number": "7",
        "name": "A6",
        "type": "input",
        "description": "Data input for channel 6. Drives inverted output Y6 when device is enabled."
      },
      {
        "number": "8",
        "name": "A7",
        "type": "input",
        "description": "Data input for channel 7. Drives inverted output Y7 when device is enabled."
      },
      {
        "number": "9",
        "name": "A8",
        "type": "input",
        "description": "Data input for channel 8. Drives inverted output Y8 when device is enabled."
      },
      {
        "number": "10",
        "name": "GND",
        "type": "power_in",
        "description": "Ground reference (0 V). Return for VCC supply current and CMOS input/output logic levels."
      },
      {
        "number": "11",
        "name": "Y8",
        "type": "tri_state",
        "description": "3-state inverted output for channel 8. High-current CMOS driver, ±6 mA at 5 V; drives up to 15 LSTTL loads. High-Z when either OE1 or OE2 is high."
      },
      {
        "number": "12",
        "name": "Y7",
        "type": "tri_state",
        "description": "3-state inverted output for channel 7. High-current CMOS driver, ±6 mA at 5 V. High-Z when either OE1 or OE2 is high."
      },
      {
        "number": "13",
        "name": "Y6",
        "type": "tri_state",
        "description": "3-state inverted output for channel 6. High-current CMOS driver, ±6 mA at 5 V. High-Z when either OE1 or OE2 is high."
      },
      {
        "number": "14",
        "name": "Y5",
        "type": "tri_state",
        "description": "3-state inverted output for channel 5. High-current CMOS driver, ±6 mA at 5 V. High-Z when either OE1 or OE2 is high."
      },
      {
        "number": "15",
        "name": "Y4",
        "type": "tri_state",
        "description": "3-state inverted output for channel 4. High-current CMOS driver, ±6 mA at 5 V. High-Z when either OE1 or OE2 is high."
      },
      {
        "number": "16",
        "name": "Y3",
        "type": "tri_state",
        "description": "3-state inverted output for channel 3. High-current CMOS driver, ±6 mA at 5 V. High-Z when either OE1 or OE2 is high."
      },
      {
        "number": "17",
        "name": "Y2",
        "type": "tri_state",
        "description": "3-state inverted output for channel 2. High-current CMOS driver, ±6 mA at 5 V. High-Z when either OE1 or OE2 is high."
      },
      {
        "number": "18",
        "name": "Y1",
        "type": "tri_state",
        "description": "3-state inverted output for channel 1. High-current CMOS driver, ±6 mA at 5 V. High-Z when either OE1 or OE2 is high."
      },
      {
        "number": "19",
        "name": "OE2",
        "type": "input",
        "description": "Active-low output-enable 2. NORed with OE1; when either OE input is high, all Y outputs are in high-impedance state."
      },
      {
        "number": "20",
        "name": "VCC",
        "type": "power_in",
        "description": "Positive supply, 2 V to 6 V recommended (absolute max 7 V). Bypass with 0.1 µF (optionally paralleled with 1 µF) placed close to the pin."
      }
    ],
    "provenance": {
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      "datasheet": {
        "url": "https://www.ti.com/lit/ds/symlink/sn74hc540.pdf",
        "pages": 25,
        "sha256": "d54581bf2a2bec36",
        "source_tier": "mfr"
      },
      "cad": "KiCad official (CC-BY-SA 4.0)",
      "pins": {
        "total": 20,
        "described": 20,
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        "refuses_to_fabricate": true
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    "logic": {
      "family_id": "74HC540",
      "logic_family": "74HC",
      "function_code": "540",
      "function_class": "Buffer",
      "function_name": "Octal Inverting Buffer, 3-State",
      "manufacturer": "Texas Instruments",
      "is_specialty": false
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  },
  "metadata": {
    "specs": {
      "Type": "Octal inverting buffer / line driver, 3-state",
      "Logic family": "74HC (CMOS)",
      "Configuration": "8 inverting buffers, flow-through pinout",
      "Supply voltage": "2 V to 6 V",
      "Output current": "+-6 mA at VCC = 4.5 V",
      "Propagation delay": "14 ns typ at 5 V",
      "Operating temperature": "-40 C to 85 C"
    }
  },
  "sections": [
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  "discovery_triggers": [
    "inverting octal buffer",
    "bus driver",
    "3-state inverter",
    "flow-through buffer"
  ],
  "discovery_pitch": "Eight inverting 3-state buffers with a flow-through pinout for clean bus driving and isolation.",
  "author": {
    "name": "Ray",
    "email": "[email protected]"
  },
  "dependencies": {},
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  "variants": [
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      "mpn": "SN74HC540DW",
      "kind": "unknown"
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    {
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      "kind": "unknown"
    },
    {
      "mpn": "SN74HC540NS",
      "kind": "unknown"
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    {
      "mpn": "SN74HC540NSR",
      "kind": "unknown"
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    {
      "mpn": "SN74HC540PW",
      "kind": "unknown"
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    {
      "mpn": "SN74HC540J",
      "kind": "unknown"
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    {
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