SBAU448 September   2024 ADS8681W

 

  1.   1
  2.   Description
  3.   Get Started
  4.   Features
  5.   Applications
  6.   6
  7. 1Evaluation Module Overview
    1. 1.1 Introduction
    2. 1.2 Performance Development Kit Contents
    3. 1.3 Specification
    4. 1.4 Device Information
  8. 2Hardware
    1. 2.1 EVM Analog Interface
      1. 2.1.1 ADC Analog Input Signal Path
      2. 2.1.2 Onboard ADC Reference
    2. 2.2 Power Supplies
  9. 3Software
    1. 3.1 Digital Interfaces
      1. 3.1.1 multiSPITM SPI for ADC Digital IO
    2. 3.2 ADS8681WEVM-PDK Initial Setup
      1. 3.2.1 Default Jumper and Switch Settings
      2. 3.2.2 EVM Graphical User Interface (GUI) Software Installation
  10. 4Implementation Results
    1. 4.1 ADS8681WEVM-PDK Operation
      1. 4.1.1 EVM GUI Global Settings for ADC control
      2. 4.1.2 Register Map Configuration Tool
      3. 4.1.3 Time Domain Display Tool
      4. 4.1.4 Histogram Tool
      5. 4.1.5 Spectral Analysis Tool
      6. 4.1.6 Linearity Analysis Tool
  11. 5Hardware Design Files
    1. 5.1 ADS8681WEVM-PDK Schematic
    2. 5.2 PCB Layout
    3. 5.3 Bill of Materials
  12. 6Additional Information
    1. 6.1 Trademarks
  13. 7Related Documentation

1.4 Device Information

The ADS8681W is a high-speed, high-performance, easy-to-use integrated data acquisition system device. This single-channel device supports true bipolar differential and single-ended input voltage swings up to ±12.288V and operates on a single 5V analog supply

The ADS8681W consists of a high-precision successive approximation register (SAR) analog-to-digital converter (ADC) and a power-optimized analog front-end (AFE) circuit for signal conditioning. The ADS8681W includes:

  • A high-resistive input impedance (≥ 1MΩ) that is independent of the sampling rate
  • A programmable gain amplifier (PGA) with a differential and single-ended input configuration supporting nine software-programmable unipolar and bipolar input ranges
  • A second-order, low-pass anti-aliasing filter
  • An ADC driver amplifier that provides quick settling of the SAR ADC input for high accuracy
  • An input over-voltage protection circuit up to ±20V

The integrated precision AFE circuit includes high input impedance and a precision ADC operating from a single 5V supply. This AFE circuit offers a simplified end design without requiring external high-voltage bipolar supplies and complicated driver circuits.