SBAU351 April   2021

 

  1.   Trademarks
  2. 1EVM Overview
    1. 1.1 ADS127L11EVM Kit
    2. 1.2 ADS127L11EVM Board
    3. 1.3 ADS127L11EVM-PDK-GUI Unsupported Features
  3. 2EVM Analog Interface
    1. 2.1 EVM Analog Input Options
    2. 2.2 ADC Connections and Decoupling
    3. 2.3 ADC Input Drive Amplifiers
    4. 2.4 VCOM Buffer
    5. 2.5 Onboard Voltage Reference
    6. 2.6 External Voltage Reference
    7. 2.7 Clock Tree
  4. 3Digital Interface
    1. 3.1 Serial Interface (SPI)
    2. 3.2 I2C Bus for Onboard EEPROM
  5. 4Power Supplies
    1. 4.1 Power Connection and Configuration
    2. 4.2 Low Dropout Regulator (LDO)
  6. 5ADS127L11EVM Software Installation
  7. 6EVM Operation
    1. 6.1 Connecting the Hardware
    2. 6.2 Optional Connections to the EVM
    3. 6.3 EVM GUI Global Settings for ADC Control
    4. 6.4 Time Domain Display
    5. 6.5 Frequency Domain Display
    6. 6.6 Histogram Display
  8. 7Bill of Materials, Schematics, and Layout
    1. 7.1 Bill of Materials
    2. 7.2 Board Layouts
    3. 7.3 Schematics
  9. 8References

6.5 Frequency Domain Display

The spectral analysis tool, shown in Figure 6-6, is intended to evaluate the dynamic performance (SNR, THD, SFDR, SINAD, and ENOB) of the ADS127L11 ADC through single-tone sinusoidal signal FFT analysis using the 7-term Blackman-Harris window setting. The FFT tool includes windowing options that are required to mitigate the effects of non-coherent sampling (this discussion is beyond the scope of this document). The 7-Term Blackman-Harris window is the default option and has sufficient dynamic range to resolve the frequency components of up to a 24-bit ADC. The None option corresponds to not using a window (or using a rectangular window) and is not recommended.

GUID-4B8A255A-47A9-4C81-B25F-E2E705DEF287-low.gifFigure 6-6 Frequency Domain Display