SBAA520A July   2021  – December 2025 ADS117L11 , ADS127L11 , ADS127L14 , ADS127L18 , ADS127L21 , ADS127L21B

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1 Introduction
  5. 2 Clock Signal
    1. 2.1 Single Clock Buffer
    2. 2.2 Multiple Clock Buffers
    3. 2.3 Clock Jitter
  6. 3 Synchronization
  7. 4 Anti-Alias Filter Group Delay
  8. 5 Reference Voltage
  9. 6 Power Supply Bypassing and Grounding
  10. 7 SPI Daisy-Chain Connection
    1. 7.1 SPI Daisy-Chain Communication
    2. 7.2 System Requirements for SPI Daisy-Chain Configuration
    3. 7.3 Number of Devices in a SPI Daisy-Chain Connection for Single Channel ADCs
  11. 8 Parallel SPI SDO or DRDY Connection for Single Channel ADCs
  12. 9 Determining When New Conversion Data is Available for Single Channel ADCs
  13. 10Frame-Sync Daisy-Chain Connection for Multi-Channel ADCs
    1. 10.1 System Requirements for Frame-Sync Daisy-Chain Configuration
    2. 10.2 Number of Channels in a Frame-Sync Daisy-Chain Connection
  14. 11Summary
  15. 12References
  16. 13Revision History

Abstract

Multiple ADC devices operating in simultaneous-sampling mode are often used in data acquisition systems. Examples include sound and vibration sensors, electrical grid monitoring, and medical equipment, including ECG and in-vitro diagnostics. Texas Instruments' family of wide bandwidth delta-sigma ADCs are designed for these applications because of the small package size, daisy-chain connection options, and ability to synchronize. This application note discusses many of the design requirements for these multichannel systems.