SBAU436B January   2024  – February 2025

 

  1.   1
  2.   Description
  3.   Get Started
  4.   Features
  5.   Applications
  6.   6
  7. 1Evaluation Module Overview
    1. 1.1 Introduction
    2. 1.2 Kit Contents
    3. 1.3 Specification
    4. 1.4 Device Information
  8. 2Hardware
    1. 2.1 EVM Analog Input Options
      1. 2.1.1 Differential SMA Inputs
      2. 2.1.2 Single-Ended SMA Inputs
      3. 2.1.3 Differential Input Pins
    2. 2.2 Power Supplies
    3. 2.3 ADC Connections and Decoupling
    4. 2.4 ADC Input Amplifiers
    5. 2.5 VCOM Buffer
    6. 2.6 Voltage Reference
    7. 2.7 Clock Tree
    8. 2.8 Digital Interfaces
    9. 2.9 Using the ADS1278EVM With an External Controller
  9. 3Software
    1. 3.1 ADS1278EVM Software Installation
  10. 4Implementation Results
    1. 4.1 Hardware Connections
    2. 4.2 GUI Settings for ADC Control
    3. 4.3 Time Domain Display
    4. 4.4 Frequency Domain Display
    5. 4.5 Histogram Display
  11. 5Hardware Design Files
    1. 5.1 Schematics
    2. 5.2 PCB Layouts
    3. 5.3 Bill of Materials (BOM)
  12. 6Additional Information
    1. 6.1 Trademarks
  13. 7References
  14. 8Revision History
  15. 9Revision History

2.1.1 Differential SMA Inputs

For best performance, connect differential analog input signals through the SMA connectors on channels 1 and 2, as shown in Figure 2-1. Alternatively, headers are provided to directly connect inputs for dc measurements, or where best ac performance is not needed. A possibility is to use the fully-differential SMA inputs as single-ended inputs. Connect the single-ended input to either the AINP or AINN SMA connector, then use the supplied shunt to connect the unused input to GND via the header. The input driver circuits use the THS4551 fully-differential amplifier in a low pass, unity-gain configuration with an additional single-pole RC filter at the output. Multiple passive components around the amplifier are intentionally left uninstalled to give users the flexibility to customize the input drive circuit for specific application.

ADS1278V2EVM-PDK SMA Input ConnectionsFigure 2-1 SMA Input Connections