ADS8681

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  "type": "component",
  "slug": "ads8681",
  "title": "ADS8681",
  "brief": "TI 18-bit, 1 MSPS SAR ADC with integrated reference, QFN-16. Bipolar input range, SPI. Datasheet-verified.",
  "version": "0.1.0",
  "license": "CC-BY-SA-4.0",
  "tags": [
    "component",
    "data-converter",
    "adc",
    "sar-adc",
    "18-bit",
    "spi",
    "qfn-16",
    "texas-instruments"
  ],
  "component": {
    "mpn": "ADS8681",
    "manufacturer": "Texas Instruments",
    "package": "QFN-16",
    "pin_count": 16,
    "category": "Data Converter",
    "subcategory": "SAR ADC",
    "datasheet": "https://www.ti.com/lit/ds/symlink/ads8681.pdf",
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    "pins": [
      {
        "number": "1",
        "name": "AGND",
        "type": "power_in",
        "description": "Analog ground pin. Decouple with the AVDD pin."
      },
      {
        "number": "2",
        "name": "REFIO",
        "type": "bidirectional",
        "description": "Internal 4.096 V reference output and external reference input pin. Decouple with REFGND."
      },
      {
        "number": "3",
        "name": "REFGND",
        "type": "power_in",
        "description": "Reference ground pin; short to the analog ground plane. Decouple with the REFIO and REFCAP pins."
      },
      {
        "number": "4",
        "name": "REFCAP",
        "type": "passive",
        "description": "ADC reference buffer decoupling capacitor pin. Decouple with the REFGND pin."
      },
      {
        "number": "5",
        "name": "AIN_P",
        "type": "input",
        "description": "Analog input: positive. Constant resistive input impedance ≥1 MΩ with overvoltage protection up to ±20 V. Decouple with the AIN_GND pin."
      },
      {
        "number": "6",
        "name": "AIN_GND",
        "type": "input",
        "description": "Analog input: negative. Constant resistive input impedance ≥1 MΩ with overvoltage protection up to ±20 V. Decouple with the AIN_P pin."
      },
      {
        "number": "7",
        "name": "RST",
        "type": "input",
        "description": "Active low logic input to reset the device."
      },
      {
        "number": "8",
        "name": "SDI",
        "type": "input",
        "description": "Dual function: data input pin (MOSI) for serial communication; chain data input during serial communication in daisy-chain mode."
      },
      {
        "number": "9",
        "name": "CONVST/CS",
        "type": "input",
        "description": "Dual-function pin. Active-high logic: CONVST rising edge starts a conversion (acquisition→conversion). Active-low logic: chip-select input; device drives the data bus when CS is low, SDO-x go tri-state when CS is high."
      },
      {
        "number": "10",
        "name": "SCLK",
        "type": "input",
        "description": "Serial communication clock input pin; all system-synchronous data transfer protocols are timed with respect to SCLK."
      },
      {
        "number": "11",
        "name": "SDO-0",
        "type": "output",
        "description": "Serial communication: data output 0 (MISO)."
      },
      {
        "number": "12",
        "name": "SDO-1",
        "type": "output",
        "description": "Multifunction output pin: active-high ALARM flag, data output 1 for serial communication, or general-purpose output. Function selected via configuration register."
      },
      {
        "number": "13",
        "name": "RVS",
        "type": "output",
        "description": "Multifunction output pin for serial interface. With CS high, RVS reflects the internal ADCST signal; with CS low, RVS status depends on the output protocol selection."
      },
      {
        "number": "14",
        "name": "DVDD",
        "type": "power_in",
        "description": "Digital supply pin (1.65 V to AVDD, nominal 3.3 V). Decouple with the DGND pin."
      },
      {
        "number": "15",
        "name": "DGND",
        "type": "power_in",
        "description": "Digital ground pin. Decouple with the DVDD pin."
      },
      {
        "number": "16",
        "name": "AVDD",
        "type": "power_in",
        "description": "Analog supply pin (4.75 V to 5.25 V nominal 5 V). Decouple with the AGND pin."
      }
    ],
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        "total": 16,
        "described": 16,
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  "metadata": {
    "specs": {
      "Type": "18-bit SAR ADC",
      "Throughput": "1 MSPS",
      "Input": "Single-ended, bipolar/unipolar ranges",
      "Interface": "SPI",
      "Reference": "Integrated + buffer",
      "Extras": "ALARM over-range flag",
      "Supply": "AVDD 5 V, DVDD 1.65-5.5 V",
      "Package": "QFN-16"
    }
  },
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  "discovery_triggers": [
    "ads8681",
    "18-bit adc",
    "1msps sar adc",
    "precision adc bipolar input"
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  "discovery_pitch": "TI ADS8681 18-bit 1 MSPS SAR ADC (QFN-16) with datasheet-verified pinout, KiCad symbol/footprint/3D, and full provenance.",
  "author": {
    "name": "Ray",
    "email": "[email protected]"
  },
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