SN74HC194 Universal Shift Register

{
  "schema_version": 1,
  "type": "component",
  "slug": "sn74hc194",
  "title": "SN74HC194 Universal Shift Register",
  "brief": "4-bit bidirectional universal shift register with parallel load and shift-left/right control.",
  "version": "0.1.0",
  "license": "CC-BY-SA-4.0",
  "tags": [
    "logic",
    "shift-register",
    "bidirectional",
    "universal",
    "74hc",
    "ti",
    "soic-16"
  ],
  "component": {
    "mpn": "SN74HC194",
    "manufacturer": "Texas Instruments",
    "package": "SOIC-16",
    "pin_count": 16,
    "category": "Logic",
    "subcategory": "Shift Register",
    "datasheet": "https://www.ti.com/lit/ds/symlink/cd74hc194.pdf",
    "parts": {
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    "distributor_links": {},
    "pins": [
      {
        "number": "1",
        "name": "MR",
        "type": "input",
        "description": "Asynchronous Master Reset, active-low. When driven low, all four internal flip-flops are cleared and Q0-Q3 are forced to logic Low regardless of the clock. Minimum MR pulse width is 16ns at VCC=4.5V."
      },
      {
        "number": "2",
        "name": "DSR",
        "type": "input",
        "description": "Serial data input for shift-right mode. The logic level on DSR is clocked into Q0 on the rising edge of CP when S1=Low, S0=High."
      },
      {
        "number": "3",
        "name": "D0",
        "type": "input",
        "description": "Parallel data input D0. Loaded into flip-flop Q0 on the rising edge of CP when S0=High and S1=High (parallel load mode)."
      },
      {
        "number": "4",
        "name": "D1",
        "type": "input",
        "description": "Parallel data input D1. Loaded into flip-flop Q1 on the rising edge of CP when S0=High and S1=High (parallel load mode)."
      },
      {
        "number": "5",
        "name": "D2",
        "type": "input",
        "description": "Parallel data input D2. Loaded into flip-flop Q2 on the rising edge of CP when S0=High and S1=High (parallel load mode)."
      },
      {
        "number": "6",
        "name": "D3",
        "type": "input",
        "description": "Parallel data input D3. Loaded into flip-flop Q3 on the rising edge of CP when S0=High and S1=High (parallel load mode)."
      },
      {
        "number": "7",
        "name": "DSL",
        "type": "input",
        "description": "Serial data input for shift-left mode. The logic level on DSL is clocked into Q3 on the rising edge of CP when S1=High, S0=Low."
      },
      {
        "number": "8",
        "name": "GND",
        "type": "power_in",
        "description": "Ground reference (0V) for the device."
      },
      {
        "number": "9",
        "name": "S0",
        "type": "input",
        "description": "Mode select input S0. Combined with S1 selects one of four operating modes: hold (S1=L,S0=L), shift-right (S1=L,S0=H), shift-left (S1=H,S0=L), parallel load (S1=H,S0=H)."
      },
      {
        "number": "10",
        "name": "S1",
        "type": "input",
        "description": "Mode select input S1. See S0 for the mode encoding table."
      },
      {
        "number": "11",
        "name": "CP",
        "type": "input",
        "description": "Clock input. All synchronous operations (shift-right, shift-left, parallel-load, hold) occur on the rising (Low-to-High) edge of CP. Typical fMAX = 60MHz at VCC=5V, CL=15pF."
      },
      {
        "number": "12",
        "name": "Q3",
        "type": "output",
        "description": "Parallel output Q3, the MSB of the shift register. Drives standard-output loads (10 LSTTL). Cleared to Low on MR=Low."
      },
      {
        "number": "13",
        "name": "Q2",
        "type": "output",
        "description": "Parallel output Q2. Drives standard-output loads (10 LSTTL). Cleared to Low on MR=Low."
      },
      {
        "number": "14",
        "name": "Q1",
        "type": "output",
        "description": "Parallel output Q1. Drives standard-output loads (10 LSTTL). Cleared to Low on MR=Low."
      },
      {
        "number": "15",
        "name": "Q0",
        "type": "output",
        "description": "Parallel output Q0, the LSB of the shift register. Drives standard-output loads (10 LSTTL). Cleared to Low on MR=Low."
      },
      {
        "number": "16",
        "name": "VCC",
        "type": "power_in",
        "description": "Positive supply voltage. 2V to 6V for HC types, 4.5V to 5.5V for HCT types. Bypass with a 100nF ceramic capacitor close to the pin."
      }
    ],
    "provenance": {
      "extractor": "ds2sf",
      "datasheet": {
        "url": "https://www.ti.com/lit/ds/symlink/cd74hc194.pdf",
        "pages": 19,
        "sha256": "209a444fe7a9beeb",
        "source_tier": "mfr"
      },
      "cad": "KiCad official (CC-BY-SA 4.0)",
      "pins": {
        "total": 16,
        "described": 16,
        "cites_pages": true,
        "refuses_to_fabricate": true
      }
    },
    "viewers": {
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    "logic": {
      "family_id": "74HC194",
      "logic_family": "74HC",
      "function_code": "194",
      "function_class": null,
      "function_name": null,
      "manufacturer": "Texas Instruments",
      "is_specialty": false
    },
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        "role": "plain",
        "up": "Z",
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        "zmin_mm": -0.0,
        "centre_offset_mm": 0.0,
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  },
  "metadata": {
    "specs": {
      "Type": "4-bit bidirectional universal shift register",
      "Logic family": "74HC (CMOS)",
      "Modes": "Shift left, shift right, parallel load, hold",
      "Clear": "Active-low, asynchronous",
      "Supply voltage": "2 V to 6 V",
      "Max clock": "50 MHz typ at 5 V",
      "Operating temperature": "-40 C to 85 C"
    }
  },
  "sections": [
    "hero",
    "viewers",
    "readme",
    "breadcrumbs",
    "info"
  ],
  "discovery_triggers": [
    "universal shift register",
    "bidirectional shift register",
    "parallel load shift",
    "shift left right"
  ],
  "discovery_pitch": "A 4-bit register that shifts left, shifts right, parallel-loads, or holds under two mode pins.",
  "author": {
    "name": "Ray",
    "email": "[email protected]"
  },
  "dependencies": {},
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  "variants": [
    {
      "mpn": "SN74HC194E",
      "kind": "unknown"
    },
    {
      "mpn": "SN74HC194M",
      "kind": "unknown"
    },
    {
      "mpn": "SN74HC194MT",
      "kind": "unknown"
    },
    {
      "mpn": "SN74HC194M96",
      "kind": "unknown"
    },
    {
      "mpn": "SN74HC194NSR",
      "kind": "unknown"
    },
    {
      "mpn": "SN74HC194PW",
      "kind": "unknown"
    },
    {
      "mpn": "SN74HC194PWR",
      "kind": "unknown"
    },
    {
      "mpn": "SN74HC194PWT",
      "kind": "unknown"
    },
    {
      "mpn": "SN74HC194F3A",
      "kind": "unknown"
    }
  ]
}