SBAU411 February   2023 ADS127L21

 

  1.   Abstract
  2.   Trademarks
  3. 1EVM Overview
    1. 1.1 ADS127L21 EVM Kit
    2. 1.2 ADS127L21EVM Board
    3. 1.3 ADS127L21EVM-PDK-GUI Unsupported Features
    4. 1.4 Related Documentation
  4. 2Analog 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
  5. 3Digital Interface
    1. 3.1 Serial Interface
    2. 3.2 I2C bus for Onboard EEPROM
  6. 4Power Supplies
    1. 4.1 Power Connection and Configuration
    2. 4.2 Low Dropout Regulator (LDO)
  7. 5ADS127L21 EVM Software Installation
  8. 6EVM Operation
    1. 6.1 Connecting the Hardware
    2. 6.2 Optional EVM Connections
    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
    7. 6.7 Digital Filter Configuration
    8. 6.8 Digital Filter Response
  9. 7Bill of Materials, Schematics, and Layout
    1. 7.1 Bill of Materials
    2. 7.2 Schematics
    3. 7.3 Board Layout

2.5 Onboard Voltage Reference

#GUID-46F1D426-DE3A-4ADD-9ECC-FA90B5D27C58 shows the REF6225 configuration. This reference includes an integrated wide bandwidth buffer that makes the REF6225 designed for driving the switched-capacitor input to the ADS127L21. There are also unpopulated 0-Ω resistors that allow use of the REF70 reference if higher DC precision is needed. The EVM provides a buffer and connections if a different voltage reference is chosen. This reference is sufficient to meet the ADS127L21 data sheet specifications for dynamic performance.

Figure 2-4 Onboard Voltage Reference