SBAU353 October   2021

 

  1.   Trademarks
  2. 1EVM Overview
    1. 1.1 ADS131A04EVM Kit
    2. 1.2 ADS131A04EVM Board
  3. 2ADS131A04EVM Quick Start Guide
  4. 3EVM Analog Interface
    1. 3.1 ADC Analog Input Signal Path
    2. 3.2 ADC External Clock (XTAL1/CLKIN and XTAL2) Options
  5. 4Digital Interface
    1. 4.1 SPI Communication
    2. 4.2 Connection to the PHI
    3. 4.3 Digital Header
    4. 4.4 LaunchPad Connectors
  6. 5Power Supplies
  7. 6ADS131A04EVM Initial Setup
    1. 6.1 Default Jumper Settings
    2. 6.2 EVM Graphical User Interface (GUI) Software Installation
  8. 7ADS131A04EVM Software Reference
    1. 7.1 EVM GUI Global Settings for ADC Control
    2. 7.2 Register Map Configuration Tool
    3. 7.3 Time Domain Display Tool
    4. 7.4 Spectral Analysis Tool
    5. 7.5 Histogram Tool
  9. 8ADS131A04EVM Bill of Materials, PCB Layout, and Schematic
    1. 8.1 Bill of Materials
    2. 8.2 PCB Layout
    3. 8.3 Schematic
  10. 9References

4.1 SPI Communication

The ADS131A04EVM supports limited interface modes as detailed in the ADS131A04 data sheet. The ADS131A04 uses an SPI-compatible interface to configure the device and retrieve conversion data. SPI communication on the ADS131A04 is performed in frames. Each SPI communication frame consists of several words. The word size is configurable as either 16 bits, 24 bits (default), or 32 bits by setting the state of M1 pin to Hi-Z, GND, or IOVDD, respectively.

For this EVM not all modes and functions for this SPI communication are supported. Specifically, the EVM GUI software expects SPI words size to be 24 bits. For more information about the SPI communication, see the ADS131A0x 2- or 4-Channel, 24-Bit, 128-kSPS, Simultaneous-Sampling, Delta-Sigma ADC Data Sheet.